// You can set the following variables before loading this script:
//
// var netdataNoDygraphs = true;        // do not use dygraph
// var netdataNoSparklines = true;      // do not use sparkline
// var netdataNoPeitys = true;          // do not use peity
// var netdataNoGoogleCharts = true;    // do not use google
// var netdataNoMorris = true;          // do not use morris
// var netdataNoEasyPieChart = true;    // do not use easy pie chart
// var netdataNoGauge = true;           // do not use gauge.js
// var netdataNoD3 = true;              // do not use D3
// var netdataNoC3 = true;              // do not use C3
// var netdataNoBootstrap = true;       // do not load bootstrap
// var netdataDontStart = true;         // do not start the thread to process the charts
// var netdataErrorCallback = null;     // Callback function that will be invoked upon error
// var netdataNoRegistry = true;        // Don't update the registry for this access
// var netdataRegistryCallback = null;  // Callback function that will be invoked with one param,
//                                         the URLs from the registry
// var netdataShowHelp = true;          // enable/disable help
// var netdataShowAlarms = true;        // enable/disable help
//
// You can also set the default netdata server, using the following.
// When this variable is not set, we assume the page is hosted on your
// netdata server already.
// var netdataServer = "http://yourhost:19999"; // set your NetData server

//(function(window, document, undefined) {

    // ------------------------------------------------------------------------
    // compatibility fixes

    // fix IE issue with console
    if(!window.console) { window.console = { log: function(){} }; }

    // if string.endsWith is not defined, define it
    if(typeof String.prototype.endsWith !== 'function') {
        String.prototype.endsWith = function(s) {
            if(s.length > this.length) return false;
            return this.slice(-s.length) === s;
        };
    }

    // if string.startsWith is not defined, define it
    if(typeof String.prototype.startsWith !== 'function') {
        String.prototype.startsWith = function(s) {
            if(s.length > this.length) return false;
            return this.slice(s.length) === s;
        };
    }

    // global namespace
    var NETDATA = window.NETDATA || {};

    // ----------------------------------------------------------------------------------------------------------------
    // Detect the netdata server

    // http://stackoverflow.com/questions/984510/what-is-my-script-src-url
    // http://stackoverflow.com/questions/6941533/get-protocol-domain-and-port-from-url
    NETDATA._scriptSource = function() {
        var script = null;

        if(typeof document.currentScript !== 'undefined') {
            script = document.currentScript;
        }
        else {
            var all_scripts = document.getElementsByTagName('script');
            script = all_scripts[all_scripts.length - 1];
        }

        if (typeof script.getAttribute.length !== 'undefined')
            script = script.src;
        else
            script = script.getAttribute('src', -1);

        return script;
    };

    if(typeof netdataServer !== 'undefined')
        NETDATA.serverDefault = netdataServer;
    else {
        var s = NETDATA._scriptSource();
        if(s) NETDATA.serverDefault = s.replace(/\/dashboard.js(\?.*)*$/g, "");
        else {
            console.log('WARNING: Cannot detect the URL of the netdata server.');
            NETDATA.serverDefault = null;
        }
    }

    if(NETDATA.serverDefault === null)
        NETDATA.serverDefault = '';
    else if(NETDATA.serverDefault.slice(-1) !== '/')
        NETDATA.serverDefault += '/';

    // default URLs for all the external files we need
    // make them RELATIVE so that the whole thing can also be
    // installed under a web server
    NETDATA.jQuery              = NETDATA.serverDefault + 'lib/jquery-1.12.0.min.js';
    NETDATA.peity_js            = NETDATA.serverDefault + 'lib/jquery.peity.min.js';
    NETDATA.sparkline_js        = NETDATA.serverDefault + 'lib/jquery.sparkline.min.js';
    NETDATA.easypiechart_js     = NETDATA.serverDefault + 'lib/jquery.easypiechart.min.js';
    NETDATA.gauge_js            = NETDATA.serverDefault + 'lib/gauge.min.js';
    NETDATA.dygraph_js          = NETDATA.serverDefault + 'lib/dygraph-combined.js';
    NETDATA.dygraph_smooth_js   = NETDATA.serverDefault + 'lib/dygraph-smooth-plotter.js';
    NETDATA.raphael_js          = NETDATA.serverDefault + 'lib/raphael-min.js';
    NETDATA.morris_js           = NETDATA.serverDefault + 'lib/morris.min.js';
    NETDATA.d3_js               = NETDATA.serverDefault + 'lib/d3.min.js';
    NETDATA.c3_js               = NETDATA.serverDefault + 'lib/c3.min.js';
    NETDATA.c3_css              = NETDATA.serverDefault + 'css/c3.min.css';
    NETDATA.morris_css          = NETDATA.serverDefault + 'css/morris.css';
    NETDATA.google_js           = 'https://www.google.com/jsapi';

    NETDATA.themes = {
        white: {
            bootstrap_css: NETDATA.serverDefault + 'css/bootstrap.min.css',
            dashboard_css: NETDATA.serverDefault + 'dashboard.css',
            background: '#FFFFFF',
            foreground: '#000000',
            grid: '#DDDDDD',
            axis: '#CCCCCC',
            colors: [   '#3366CC', '#DC3912',   '#109618', '#FF9900',   '#990099', '#DD4477',
                        '#3B3EAC', '#66AA00',   '#0099C6', '#B82E2E',   '#AAAA11', '#5574A6',
                        '#994499', '#22AA99',   '#6633CC', '#E67300',   '#316395', '#8B0707',
                        '#329262', '#3B3EAC' ],
            easypiechart_track: '#f0f0f0',
            easypiechart_scale: '#dfe0e0',
            gauge_pointer: '#C0C0C0',
            gauge_stroke: '#F0F0F0',
            gauge_gradient: false
        },
        slate: {
            bootstrap_css: NETDATA.serverDefault + 'css/bootstrap.slate.min.css',
            dashboard_css: NETDATA.serverDefault + 'dashboard.slate.css',
            background: '#272b30',
            foreground: '#C8C8C8',
            grid: '#373b40',
            axis: '#373b40',
/*          colors: [   '#55bb33', '#ff2222',   '#0099C6', '#faa11b',   '#adbce0', '#DDDD00',
                        '#4178ba', '#f58122',   '#a5cc39', '#f58667',   '#f5ef89', '#cf93c0',
                        '#a5d18a', '#b8539d',   '#3954a3', '#c8a9cf',   '#c7de8a', '#fad20a',
                        '#a6a479', '#a66da8' ],
*/
            colors: [   '#66AA00', '#FE3912',   '#3366CC', '#D66300',   '#0099C6', '#DDDD00',
                        '#5054e6', '#EE9911',   '#BB44CC', '#e45757',   '#ef0aef', '#CC7700',
                        '#22AA99', '#109618',   '#905bfd', '#f54882',   '#4381bf', '#ff3737',
                        '#329262', '#3B3EFF' ],
            easypiechart_track: '#373b40',
            easypiechart_scale: '#373b40',
            gauge_pointer: '#474b50',
            gauge_stroke: '#373b40',
            gauge_gradient: false
        }
    };

    if(typeof netdataTheme !== 'undefined' && typeof NETDATA.themes[netdataTheme] !== 'undefined')
        NETDATA.themes.current = NETDATA.themes[netdataTheme];
    else
        NETDATA.themes.current = NETDATA.themes.white;

    if(typeof netdataShowHelp === 'undefined')
        netdataShowHelp = true;

    if(typeof netdataShowAlarms === 'undefined')
        netdataShowAlarms = true;

    NETDATA.colors = NETDATA.themes.current.colors;

    // these are the colors Google Charts are using
    // we have them here to attempt emulate their look and feel on the other chart libraries
    // http://there4.io/2012/05/02/google-chart-color-list/
    //NETDATA.colors        = [ '#3366CC', '#DC3912', '#FF9900', '#109618', '#990099', '#3B3EAC', '#0099C6',
    //                      '#DD4477', '#66AA00', '#B82E2E', '#316395', '#994499', '#22AA99', '#AAAA11',
    //                      '#6633CC', '#E67300', '#8B0707', '#329262', '#5574A6', '#3B3EAC' ];

    // an alternative set
    // http://www.mulinblog.com/a-color-palette-optimized-for-data-visualization/
    //                         (blue)     (red)      (orange)   (green)    (pink)     (brown)    (purple)   (yellow)   (gray)
    //NETDATA.colors        = [ '#5DA5DA', '#F15854', '#FAA43A', '#60BD68', '#F17CB0', '#B2912F', '#B276B2', '#DECF3F', '#4D4D4D' ];

    // ----------------------------------------------------------------------------------------------------------------
    // the defaults for all charts

    // if the user does not specify any of these, the following will be used

    NETDATA.chartDefaults = {
        host: NETDATA.serverDefault,    // the server to get data from
        width: '100%',                  // the chart width - can be null
        height: '100%',                 // the chart height - can be null
        min_width: null,                // the chart minimum width - can be null
        library: 'dygraph',             // the graphing library to use
        method: 'average',              // the grouping method
        before: 0,                      // panning
        after: -600,                    // panning
        pixels_per_point: 1,            // the detail of the chart
        fill_luminance: 0.8             // luminance of colors in solit areas
    };

    // ----------------------------------------------------------------------------------------------------------------
    // global options

    NETDATA.options = {
        pauseCallback: null,            // a callback when we are really paused

        pause: false,                   // when enabled we don't auto-refresh the charts

        targets: null,                  // an array of all the state objects that are
                                        // currently active (independently of their
                                        // viewport visibility)

        updated_dom: true,              // when true, the DOM has been updated with
                                        // new elements we have to check.

        auto_refresher_fast_weight: 0,  // this is the current time in ms, spent
                                        // rendering charts continiously.
                                        // used with .current.fast_render_timeframe

        page_is_visible: true,          // when true, this page is visible

        auto_refresher_stop_until: 0,   // timestamp in ms - used internaly, to stop the
                                        // auto-refresher for some time (when a chart is
                                        // performing pan or zoom, we need to stop refreshing
                                        // all other charts, to have the maximum speed for
                                        // rendering the chart that is panned or zoomed).
                                        // Used with .current.global_pan_sync_time

        last_resized: new Date().getTime(), // the timestamp of the last resize request

        last_page_scroll: 0,            // the timestamp the last time the page was scrolled

        // the current profile
        // we may have many...
        current: {
            pixels_per_point: 1,        // the minimum pixels per point for all charts
                                        // increase this to speed javascript up
                                        // each chart library has its own limit too
                                        // the max of this and the chart library is used
                                        // the final is calculated every time, so a change
                                        // here will have immediate effect on the next chart
                                        // update

            idle_between_charts: 100,   // ms - how much time to wait between chart updates

            fast_render_timeframe: 200, // ms - render continously until this time of continious
                                        // rendering has been reached
                                        // this setting is used to make it render e.g. 10
                                        // charts at once, sleep idle_between_charts time
                                        // and continue for another 10 charts.

            idle_between_loops: 500,    // ms - if all charts have been updated, wait this
                                        // time before starting again.

            idle_parallel_loops: 100,   // ms - the time between parallel refresher updates

            idle_lost_focus: 500,       // ms - when the window does not have focus, check
                                        // if focus has been regained, every this time

            global_pan_sync_time: 1000, // ms - when you pan or zoon a chart, the background
                                        // autorefreshing of charts is paused for this amount
                                        // of time

            sync_selection_delay: 1500, // ms - when you pan or zoom a chart, wait this amount
                                        // of time before setting up synchronized selections
                                        // on hover.

            sync_selection: true,       // enable or disable selection sync

            pan_and_zoom_delay: 50,     // when panning or zooming, how ofter to update the chart

            sync_pan_and_zoom: true,    // enable or disable pan and zoom sync

            pan_and_zoom_data_padding: true, // fetch more data for the master chart when panning or zooming

            update_only_visible: true,  // enable or disable visibility management

            parallel_refresher: true,   // enable parallel refresh of charts

            concurrent_refreshes: true, // when parallel_refresher is enabled, sync also the charts

            destroy_on_hide: false,     // destroy charts when they are not visible

            show_help: netdataShowHelp, // when enabled the charts will show some help
            show_help_delay_show_ms: 500,
            show_help_delay_hide_ms: 0,

            eliminate_zero_dimensions: true, // do not show dimensions with just zeros

            stop_updates_when_focus_is_lost: true, // boolean - shall we stop auto-refreshes when document does not have user focus
            stop_updates_while_resizing: 1000,  // ms - time to stop auto-refreshes while resizing the charts

            double_click_speed: 500,    // ms - time between clicks / taps to detect double click/tap

            smooth_plot: true,          // enable smooth plot, where possible

            charts_selection_animation_delay: 50, // delay to animate charts when syncing selection

            color_fill_opacity_line: 1.0,
            color_fill_opacity_area: 0.2,
            color_fill_opacity_stacked: 0.8,

            pan_and_zoom_factor: 0.25,      // the increment when panning and zooming with the toolbox
            pan_and_zoom_factor_multiplier_control: 2.0,
            pan_and_zoom_factor_multiplier_shift: 3.0,
            pan_and_zoom_factor_multiplier_alt: 4.0,

            abort_ajax_on_scroll: false,

            setOptionCallback: function() { ; }
        },

        debug: {
            show_boxes:         false,
            main_loop:          false,
            focus:              false,
            visibility:         false,
            chart_data_url:     false,
            chart_errors:       false, // FIXME
            chart_timing:       false,
            chart_calls:        false,
            libraries:          false,
            dygraph:            false
        }
    };

    NETDATA.statistics = {
        refreshes_total: 0,
        refreshes_active: 0,
        refreshes_active_max: 0
    };


    // ----------------------------------------------------------------------------------------------------------------
    // local storage options

    NETDATA.localStorage = {
        default: {},
        current: {},
        callback: {} // only used for resetting back to defaults
    };

    NETDATA.localStorageGet = function(key, def, callback) {
        var ret = def;

        if(typeof NETDATA.localStorage.default[key.toString()] === 'undefined') {
            NETDATA.localStorage.default[key.toString()] = def;
            NETDATA.localStorage.callback[key.toString()] = callback;
        }

        if(typeof Storage !== "undefined" && typeof localStorage === 'object') {
            try {
                // console.log('localStorage: loading "' + key.toString() + '"');
                ret = localStorage.getItem(key.toString());
                // console.log('netdata loaded: ' + key.toString() + ' = ' + ret.toString());
                if(ret === null || ret === 'undefined') {
                    // console.log('localStorage: cannot load it, saving "' + key.toString() + '" with value "' + JSON.stringify(def) + '"');
                    localStorage.setItem(key.toString(), JSON.stringify(def));
                    ret = def;
                }
                else {
                    // console.log('localStorage: got "' + key.toString() + '" with value "' + ret + '"');
                    ret = JSON.parse(ret);
                    // console.log('localStorage: loaded "' + key.toString() + '" as value ' + ret + ' of type ' + typeof(ret));
                }
            }
            catch(error) {
                console.log('localStorage: failed to read "' + key.toString() + '", using default: "' + def.toString() + '"');
                ret = def;
            }
        }

        if(typeof ret === 'undefined' || ret === 'undefined') {
            console.log('localStorage: LOADED UNDEFINED "' + key.toString() + '" as value ' + ret + ' of type ' + typeof(ret));
            ret = def;
        }

        NETDATA.localStorage.current[key.toString()] = ret;
        return ret;
    };

    NETDATA.localStorageSet = function(key, value, callback) {
        if(typeof value === 'undefined' || value === 'undefined') {
            console.log('localStorage: ATTEMPT TO SET UNDEFINED "' + key.toString() + '" as value ' + value + ' of type ' + typeof(value));
        }

        if(typeof NETDATA.localStorage.default[key.toString()] === 'undefined') {
            NETDATA.localStorage.default[key.toString()] = value;
            NETDATA.localStorage.current[key.toString()] = value;
            NETDATA.localStorage.callback[key.toString()] = callback;
        }

        if(typeof Storage !== "undefined" && typeof localStorage === 'object') {
            // console.log('localStorage: saving "' + key.toString() + '" with value "' + JSON.stringify(value) + '"');
            try {
                localStorage.setItem(key.toString(), JSON.stringify(value));
            }
            catch(e) {
                console.log('localStorage: failed to save "' + key.toString() + '" with value: "' + value.toString() + '"');
            }
        }

        NETDATA.localStorage.current[key.toString()] = value;
        return value;
    };

    NETDATA.localStorageGetRecursive = function(obj, prefix, callback) {
        for(var i in obj) {
            if(typeof obj[i] === 'object') {
                //console.log('object ' + prefix + '.' + i.toString());
                NETDATA.localStorageGetRecursive(obj[i], prefix + '.' + i.toString(), callback);
                continue;
            }

            obj[i] = NETDATA.localStorageGet(prefix + '.' + i.toString(), obj[i], callback);
        }
    };

    NETDATA.setOption = function(key, value) {
        if(key.toString() === 'setOptionCallback') {
            if(typeof NETDATA.options.current.setOptionCallback === 'function') {
                NETDATA.options.current[key.toString()] = value;
                NETDATA.options.current.setOptionCallback();
            }
        }
        else if(NETDATA.options.current[key.toString()] !== value) {
            var name = 'options.' + key.toString();

            if(typeof NETDATA.localStorage.default[name.toString()] === 'undefined')
                console.log('localStorage: setOption() on unsaved option: "' + name.toString() + '", value: ' + value);

            //console.log(NETDATA.localStorage);
            //console.log('setOption: setting "' + key.toString() + '" to "' + value + '" of type ' + typeof(value) + ' original type ' + typeof(NETDATA.options.current[key.toString()]));
            //console.log(NETDATA.options);
            NETDATA.options.current[key.toString()] = NETDATA.localStorageSet(name.toString(), value, null);

            if(typeof NETDATA.options.current.setOptionCallback === 'function')
                NETDATA.options.current.setOptionCallback();
        }

        return true;
    };

    NETDATA.getOption = function(key) {
        return NETDATA.options.current[key.toString()];
    };

    // read settings from local storage
    NETDATA.localStorageGetRecursive(NETDATA.options.current, 'options', null);

    // always start with this option enabled.
    NETDATA.setOption('stop_updates_when_focus_is_lost', true);

    NETDATA.resetOptions = function() {
        for(var i in NETDATA.localStorage.default) {
            var a = i.split('.');

            if(a[0] === 'options') {
                if(a[1] === 'setOptionCallback') continue;
                if(typeof NETDATA.localStorage.default[i] === 'undefined') continue;
                if(NETDATA.options.current[i] === NETDATA.localStorage.default[i]) continue;

                NETDATA.setOption(a[1], NETDATA.localStorage.default[i]);
            }
            else if(a[0] === 'chart_heights') {
                if(typeof NETDATA.localStorage.callback[i] === 'function' && typeof NETDATA.localStorage.default[i] !== 'undefined') {
                    NETDATA.localStorage.callback[i](NETDATA.localStorage.default[i]);
                }
            }
        }
    }

    // ----------------------------------------------------------------------------------------------------------------

    if(NETDATA.options.debug.main_loop === true)
        console.log('welcome to NETDATA');

    NETDATA.onresize = function() {
        NETDATA.options.last_resized = new Date().getTime();
        NETDATA.onscroll();
    };

    NETDATA.onscroll = function() {
        // console.log('onscroll');

        NETDATA.options.last_page_scroll = new Date().getTime();
        NETDATA.options.auto_refresher_stop_until = 0;

        if(NETDATA.options.targets === null) return;

        // when the user scrolls he sees that we have
        // hidden all the not-visible charts
        // using this little function we try to switch
        // the charts back to visible quickly
        var targets = NETDATA.options.targets;
        var len = targets.length;
        if(NETDATA.options.abort_ajax_on_scroll === true) {
            while (len--) {
                if (targets[len]._updating === true) {
                    if (typeof targets[len].xhr !== 'undefined') {
                        targets[len].xhr.abort();
                        targets[len].running = false;
                        targets[len]._updating = false;
                    }
                    targets[len].isVisible();
                }
            }
        }
        else {
            while (len--)
                targets[len].isVisible();
        }
    };

    window.onresize = NETDATA.onresize;
    window.onscroll = NETDATA.onscroll;

    // ----------------------------------------------------------------------------------------------------------------
    // Error Handling

    NETDATA.errorCodes = {
        100: { message: "Cannot load chart library", alert: true },
        101: { message: "Cannot load jQuery", alert: true },
        402: { message: "Chart library not found", alert: false },
        403: { message: "Chart library not enabled/is failed", alert: false },
        404: { message: "Chart not found", alert: false },
        405: { message: "Cannot download charts index from server", alert: true },
        406: { message: "Invalid charts index downloaded from server", alert: true },
        407: { message: "Cannot HELLO netdata server", alert: false },
        408: { message: "Netdata servers sent invalid response to HELLO", alert: false },
        409: { message: "Cannot ACCESS netdata registry", alert: false },
        410: { message: "Netdata registry ACCESS failed", alert: false },
        411: { message: "Netdata registry server send invalid response to DELETE ", alert: false },
        412: { message: "Netdata registry DELETE failed", alert: false },
        413: { message: "Netdata registry server send invalid response to SWITCH ", alert: false },
        414: { message: "Netdata registry SWITCH failed", alert: false },
        415: { message: "Netdata alarms download failed", alert: false },
        416: { message: "Netdata alarms log download failed", alert: false }
    };
    NETDATA.errorLast = {
        code: 0,
        message: "",
        datetime: 0
    };

    NETDATA.error = function(code, msg) {
        NETDATA.errorLast.code = code;
        NETDATA.errorLast.message = msg;
        NETDATA.errorLast.datetime = new Date().getTime();

        console.log("ERROR " + code + ": " + NETDATA.errorCodes[code].message + ": " + msg);

        var ret = true;
        if(typeof netdataErrorCallback === 'function') {
           ret = netdataErrorCallback('system', code, msg);
        }

        if(ret && NETDATA.errorCodes[code].alert)
            alert("ERROR " + code + ": " + NETDATA.errorCodes[code].message + ": " + msg);
    };

    NETDATA.errorReset = function() {
        NETDATA.errorLast.code = 0;
        NETDATA.errorLast.message = "You are doing fine!";
        NETDATA.errorLast.datetime = 0;
    };

    // ----------------------------------------------------------------------------------------------------------------
    // Chart Registry

    // When multiple charts need the same chart, we avoid downloading it
    // multiple times (and having it in browser memory multiple time)
    // by using this registry.

    // Every time we download a chart definition, we save it here with .add()
    // Then we try to get it back with .get(). If that fails, we download it.

    NETDATA.chartRegistry = {
        charts: {},

        fixid: function(id) {
            return id.replace(/:/g, "_").replace(/\//g, "_");
        },

        add: function(host, id, data) {
            host = this.fixid(host);
            id   = this.fixid(id);

            if(typeof this.charts[host] === 'undefined')
                this.charts[host] = {};

            //console.log('added ' + host + '/' + id);
            this.charts[host][id] = data;
        },

        get: function(host, id) {
            host = this.fixid(host);
            id   = this.fixid(id);

            if(typeof this.charts[host] === 'undefined')
                return null;

            if(typeof this.charts[host][id] === 'undefined')
                return null;

            //console.log('cached ' + host + '/' + id);
            return this.charts[host][id];
        },

        downloadAll: function(host, callback) {
            while(host.slice(-1) === '/')
                host = host.substring(0, host.length - 1);

            var self = this;

            $.ajax({
                url: host + '/api/v1/charts',
                async: true,
                cache: false,
                xhrFields: { withCredentials: true } // required for the cookie
            })
            .done(function(data) {
                if(data !== null) {
                    var h = NETDATA.chartRegistry.fixid(host);
                    self.charts[h] = data.charts;
                }
                else NETDATA.error(406, host + '/api/v1/charts');

                if(typeof callback === 'function')
                    callback(data);
            })
            .fail(function() {
                NETDATA.error(405, host + '/api/v1/charts');

                if(typeof callback === 'function')
                    callback(null);
            });
        }
    };

    // ----------------------------------------------------------------------------------------------------------------
    // Global Pan and Zoom on charts

    // Using this structure are synchronize all the charts, so that
    // when you pan or zoom one, all others are automatically refreshed
    // to the same timespan.

    NETDATA.globalPanAndZoom = {
        seq: 0,                 // timestamp ms
                                // every time a chart is panned or zoomed
                                // we set the timestamp here
                                // then we use it as a sequence number
                                // to find if other charts are syncronized
                                // to this timerange

        master: null,           // the master chart (state), to which all others
                                // are synchronized

        force_before_ms: null,  // the timespan to sync all other charts
        force_after_ms: null,

        callback: null,

        // set a new master
        setMaster: function(state, after, before) {
            if(NETDATA.options.current.sync_pan_and_zoom === false)
                return;

            if(this.master !== null && this.master !== state)
                this.master.resetChart(true, true);

            var now = new Date().getTime();
            this.master = state;
            this.seq = now;
            this.force_after_ms = after;
            this.force_before_ms = before;
            NETDATA.options.auto_refresher_stop_until = now + NETDATA.options.current.global_pan_sync_time;

            if(typeof this.callback === 'function')
                this.callback(true, after, before);
        },

        // clear the master
        clearMaster: function() {
            if(this.master !== null) {
                var st = this.master;
                this.master = null;
                st.resetChart();
            }

            this.master = null;
            this.seq = 0;
            this.force_after_ms = null;
            this.force_before_ms = null;
            NETDATA.options.auto_refresher_stop_until = 0;

            if(typeof this.callback === 'function')
                this.callback(false, 0, 0);
        },

        // is the given state the master of the global
        // pan and zoom sync?
        isMaster: function(state) {
            if(this.master === state) return true;
            return false;
        },

        // are we currently have a global pan and zoom sync?
        isActive: function() {
            if(this.master !== null && this.force_before_ms !== null && this.force_after_ms !== null && this.seq !== 0) return true;
            return false;
        },

        // check if a chart, other than the master
        // needs to be refreshed, due to the global pan and zoom
        shouldBeAutoRefreshed: function(state) {
            if(this.master === null || this.seq === 0)
                return false;

            //if(state.needsRecreation())
            //  return true;

            if(state.tm.pan_and_zoom_seq === this.seq)
                return false;

            return true;
        }
    };

    // ----------------------------------------------------------------------------------------------------------------
    // dimensions selection

    // FIXME
    // move color assignment to dimensions, here

    dimensionStatus = function(parent, label, name_div, value_div, color) {
        this.enabled = false;
        this.parent = parent;
        this.label = label;
        this.name_div = null;
        this.value_div = null;
        this.color = NETDATA.themes.current.foreground;

        if(parent.selected_count > parent.unselected_count)
            this.selected = true;
        else
            this.selected = false;

        this.setOptions(name_div, value_div, color);
    };

    dimensionStatus.prototype.invalidate = function() {
        this.name_div = null;
        this.value_div = null;
        this.enabled = false;
    };

    dimensionStatus.prototype.setOptions = function(name_div, value_div, color) {
        this.color = color;

        if(this.name_div != name_div) {
            this.name_div = name_div;
            this.name_div.title = this.label;
            this.name_div.style.color = this.color;
            if(this.selected === false)
                this.name_div.className = 'netdata-legend-name not-selected';
            else
                this.name_div.className = 'netdata-legend-name selected';
        }

        if(this.value_div != value_div) {
            this.value_div = value_div;
            this.value_div.title = this.label;
            this.value_div.style.color = this.color;
            if(this.selected === false)
                this.value_div.className = 'netdata-legend-value not-selected';
            else
                this.value_div.className = 'netdata-legend-value selected';
        }

        this.enabled = true;
        this.setHandler();
    };

    dimensionStatus.prototype.setHandler = function() {
        if(this.enabled === false) return;

        var ds = this;

        // this.name_div.onmousedown = this.value_div.onmousedown = function(e) {
        this.name_div.onclick = this.value_div.onclick = function(e) {
            e.preventDefault();
            if(ds.isSelected()) {
                // this is selected
                if(e.shiftKey === true || e.ctrlKey === true) {
                    // control or shift key is pressed -> unselect this (except is none will remain selected, in which case select all)
                    ds.unselect();

                    if(ds.parent.countSelected() === 0)
                        ds.parent.selectAll();
                }
                else {
                    // no key is pressed -> select only this (except if it is the only selected already, in which case select all)
                    if(ds.parent.countSelected() === 1) {
                        ds.parent.selectAll();
                    }
                    else {
                        ds.parent.selectNone();
                        ds.select();
                    }
                }
            }
            else {
                // this is not selected
                if(e.shiftKey === true || e.ctrlKey === true) {
                    // control or shift key is pressed -> select this too
                    ds.select();
                }
                else {
                    // no key is pressed -> select only this
                    ds.parent.selectNone();
                    ds.select();
                }
            }

            ds.parent.state.redrawChart();
        }
    };

    dimensionStatus.prototype.select = function() {
        if(this.enabled === false) return;

        this.name_div.className = 'netdata-legend-name selected';
        this.value_div.className = 'netdata-legend-value selected';
        this.selected = true;
    };

    dimensionStatus.prototype.unselect = function() {
        if(this.enabled === false) return;

        this.name_div.className = 'netdata-legend-name not-selected';
        this.value_div.className = 'netdata-legend-value hidden';
        this.selected = false;
    };

    dimensionStatus.prototype.isSelected = function() {
        return(this.enabled === true && this.selected === true);
    };

    // ----------------------------------------------------------------------------------------------------------------

    dimensionsVisibility = function(state) {
        this.state = state;
        this.len = 0;
        this.dimensions = {};
        this.selected_count = 0;
        this.unselected_count = 0;
    };

    dimensionsVisibility.prototype.dimensionAdd = function(label, name_div, value_div, color) {
        if(typeof this.dimensions[label] === 'undefined') {
            this.len++;
            this.dimensions[label] = new dimensionStatus(this, label, name_div, value_div, color);
        }
        else
            this.dimensions[label].setOptions(name_div, value_div, color);

        return this.dimensions[label];
    };

    dimensionsVisibility.prototype.dimensionGet = function(label) {
        return this.dimensions[label];
    };

    dimensionsVisibility.prototype.invalidateAll = function() {
        for(var d in this.dimensions)
            this.dimensions[d].invalidate();
    };

    dimensionsVisibility.prototype.selectAll = function() {
        for(var d in this.dimensions)
            this.dimensions[d].select();
    };

    dimensionsVisibility.prototype.countSelected = function() {
        var i = 0;
        for(var d in this.dimensions)
            if(this.dimensions[d].isSelected()) i++;

        return i;
    };

    dimensionsVisibility.prototype.selectNone = function() {
        for(var d in this.dimensions)
            this.dimensions[d].unselect();
    };

    dimensionsVisibility.prototype.selected2BooleanArray = function(array) {
        var ret = new Array();
        this.selected_count = 0;
        this.unselected_count = 0;

        for(var i = 0, len = array.length; i < len ; i++) {
            var ds = this.dimensions[array[i]];
            if(typeof ds === 'undefined') {
                // console.log(array[i] + ' is not found');
                ret.push(false);
                continue;
            }

            if(ds.isSelected()) {
                ret.push(true);
                this.selected_count++;
            }
            else {
                ret.push(false);
                this.unselected_count++;
            }
        }

        if(this.selected_count === 0 && this.unselected_count !== 0) {
            this.selectAll();
            return this.selected2BooleanArray(array);
        }

        return ret;
    };


    // ----------------------------------------------------------------------------------------------------------------
    // global selection sync

    NETDATA.globalSelectionSync = {
        state: null,
        dont_sync_before: 0,
        last_t: 0,
        slaves: [],

        stop: function() {
            if(this.state !== null)
                this.state.globalSelectionSyncStop();
        },

        delay: function() {
            if(this.state !== null) {
                this.state.globalSelectionSyncDelay();
            }
        }
    };

    // ----------------------------------------------------------------------------------------------------------------
    // Our state object, where all per-chart values are stored

    chartState = function(element) {
        var self = $(element);
        this.element = element;

        // IMPORTANT:
        // all private functions should use 'that', instead of 'this'
        var that = this;

        /* error() - private
         * show an error instead of the chart
         */
        var error = function(msg) {
            var ret = true;

            if(typeof netdataErrorCallback === 'function') {
                ret = netdataErrorCallback('chart', that.id, msg);
            }

            if(ret) {
                that.element.innerHTML = that.id + ': ' + msg;
                that.enabled = false;
                that.current = that.pan;
            }
        };

        // GUID - a unique identifier for the chart
        this.uuid = NETDATA.guid();

        // string - the name of chart
        this.id = self.data('netdata');

        // string - the key for localStorage settings
        this.settings_id = self.data('id') || null;

        // the user given dimensions of the element
        this.width = self.data('width') || NETDATA.chartDefaults.width;
        this.height = self.data('height') || NETDATA.chartDefaults.height;

        if(this.settings_id !== null) {
            this.height = NETDATA.localStorageGet('chart_heights.' + this.settings_id, this.height, function(height) {
                // this is the callback that will be called
                // if and when the user resets all localStorage variables
                // to their defaults

                resizeChartToHeight(height);
            });
        }

        // string - the netdata server URL, without any path
        this.host = self.data('host') || NETDATA.chartDefaults.host;

        // make sure the host does not end with /
        // all netdata API requests use absolute paths
        while(this.host.slice(-1) === '/')
            this.host = this.host.substring(0, this.host.length - 1);

        // string - the grouping method requested by the user
        this.method = self.data('method') || NETDATA.chartDefaults.method;

        // the time-range requested by the user
        this.after = self.data('after') || NETDATA.chartDefaults.after;
        this.before = self.data('before') || NETDATA.chartDefaults.before;

        // the pixels per point requested by the user
        this.pixels_per_point = self.data('pixels-per-point') || 1;
        this.points = self.data('points') || null;

        // the dimensions requested by the user
        this.dimensions = self.data('dimensions') || null;

        // the chart library requested by the user
        this.library_name = self.data('chart-library') || NETDATA.chartDefaults.library;

        // object - the chart library used
        this.library = null;

        // color management
        this.colors = null;
        this.colors_assigned = {};
        this.colors_available = null;

        // the element already created by the user
        this.element_message = null;

        // the element with the chart
        this.element_chart = null;

        // the element with the legend of the chart (if created by us)
        this.element_legend = null;
        this.element_legend_childs = {
            hidden: null,
            title_date: null,
            title_time: null,
            title_units: null,
            nano: null,
            nano_options: null,
            series: null
        };

        this.chart_url = null;                      // string - the url to download chart info
        this.chart = null;                          // object - the chart as downloaded from the server

        this.title = self.data('title') || null;    // the title of the chart
        this.units = self.data('units') || null;    // the units of the chart dimensions
        this.append_options = self.data('append-options') || null;  // the units of the chart dimensions

        this.running = false;                       // boolean - true when the chart is being refreshed now
        this.validated = false;                     // boolean - has the chart been validated?
        this.enabled = true;                        // boolean - is the chart enabled for refresh?
        this.paused = false;                        // boolean - is the chart paused for any reason?
        this.selected = false;                      // boolean - is the chart shown a selection?
        this.debug = false;                         // boolean - console.log() debug info about this chart

        this.netdata_first = 0;                     // milliseconds - the first timestamp in netdata
        this.netdata_last = 0;                      // milliseconds - the last timestamp in netdata
        this.requested_after = null;                // milliseconds - the timestamp of the request after param
        this.requested_before = null;               // milliseconds - the timestamp of the request before param
        this.requested_padding = null;
        this.view_after = 0;
        this.view_before = 0;

        this.auto = {
            name: 'auto',
            autorefresh: true,
            force_update_at: 0, // the timestamp to force the update at
            force_before_ms: null,
            force_after_ms: null
        };
        this.pan = {
            name: 'pan',
            autorefresh: false,
            force_update_at: 0, // the timestamp to force the update at
            force_before_ms: null,
            force_after_ms: null
        };
        this.zoom = {
            name: 'zoom',
            autorefresh: false,
            force_update_at: 0, // the timestamp to force the update at
            force_before_ms: null,
            force_after_ms: null
        };

        // this is a pointer to one of the sub-classes below
        // auto, pan, zoom
        this.current = this.auto;

        // check the requested library is available
        // we don't initialize it here - it will be initialized when
        // this chart will be first used
        if(typeof NETDATA.chartLibraries[that.library_name] === 'undefined') {
            NETDATA.error(402, that.library_name);
            error('chart library "' + that.library_name + '" is not found');
            return;
        }
        else if(NETDATA.chartLibraries[that.library_name].enabled === false) {
            NETDATA.error(403, that.library_name);
            error('chart library "' + that.library_name + '" is not enabled');
            return;
        }
        else
            that.library = NETDATA.chartLibraries[that.library_name];

        // milliseconds - the time the last refresh took
        this.refresh_dt_ms = 0;

        // if we need to report the rendering speed
        // find the element that needs to be updated
        var refresh_dt_element_name = self.data('dt-element-name') || null; // string - the element to print refresh_dt_ms

        if(refresh_dt_element_name !== null)
            this.refresh_dt_element = document.getElementById(refresh_dt_element_name) || null;
        else
            this.refresh_dt_element = null;

        this.dimensions_visibility = new dimensionsVisibility(this);

        this._updating = false;

        // ============================================================================================================
        // PRIVATE FUNCTIONS

        var createDOM = function() {
            if(that.enabled === false) return;

            if(that.element_message !== null) that.element_message.innerHTML = '';
            if(that.element_legend !== null) that.element_legend.innerHTML = '';
            if(that.element_chart !== null) that.element_chart.innerHTML = '';

            that.element.innerHTML = '';

            that.element_message = document.createElement('div');
            that.element_message.className = ' netdata-message hidden';
            that.element.appendChild(that.element_message);

            that.element_chart = document.createElement('div');
            that.element_chart.id = that.library_name + '-' + that.uuid + '-chart';
            that.element.appendChild(that.element_chart);

            if(that.hasLegend() === true) {
                that.element.className = "netdata-container-with-legend";
                that.element_chart.className = 'netdata-chart-with-legend-right netdata-' + that.library_name + '-chart-with-legend-right';

                that.element_legend = document.createElement('div');
                that.element_legend.className = 'netdata-chart-legend netdata-' + that.library_name + '-legend';
                that.element.appendChild(that.element_legend);
            }
            else {
                that.element.className = "netdata-container";
                that.element_chart.className = ' netdata-chart netdata-' + that.library_name + '-chart';

                that.element_legend = null;
            }
            that.element_legend_childs.series = null;

            if(typeof(that.width) === 'string')
                $(that.element).css('width', that.width);
            else if(typeof(that.width) === 'number')
                $(that.element).css('width', that.width + 'px');

            if(typeof(that.library.aspect_ratio) === 'undefined') {
                if(typeof(that.height) === 'string')
                    $(that.element).css('height', that.height);
                else if(typeof(that.height) === 'number')
                    $(that.element).css('height', that.height + 'px');
            }
            else {
                var w = that.element.offsetWidth;
                if(w === null || w === 0) {
                    // the div is hidden
                    // this will resize the chart when next viewed
                    that.tm.last_resized = 0;
                }
                else
                    $(that.element).css('height', (that.element.offsetWidth * that.library.aspect_ratio / 100).toString() + 'px');
            }

            if(NETDATA.chartDefaults.min_width !== null)
                $(that.element).css('min-width', NETDATA.chartDefaults.min_width);

            that.tm.last_dom_created = new Date().getTime();

            showLoading();
        };

        /* init() private
         * initialize state variables
         * destroy all (possibly) created state elements
         * create the basic DOM for a chart
         */
        var init = function() {
            if(that.enabled === false) return;

            that.paused = false;
            that.selected = false;

            that.chart_created = false;         // boolean - is the library.create() been called?
            that.updates_counter = 0;           // numeric - the number of refreshes made so far
            that.updates_since_last_unhide = 0; // numeric - the number of refreshes made since the last time the chart was unhidden
            that.updates_since_last_creation = 0; // numeric - the number of refreshes made since the last time the chart was created

            that.tm = {
                last_initialized: 0,        // milliseconds - the timestamp it was last initialized
                last_dom_created: 0,        // milliseconds - the timestamp its DOM was last created
                last_mode_switch: 0,        // milliseconds - the timestamp it switched modes

                last_info_downloaded: 0,    // milliseconds - the timestamp we downloaded the chart
                last_updated: 0,            // the timestamp the chart last updated with data
                pan_and_zoom_seq: 0,        // the sequence number of the global synchronization
                                            // between chart.
                                            // Used with NETDATA.globalPanAndZoom.seq
                last_visible_check: 0,      // the time we last checked if it is visible
                last_resized: 0,            // the time the chart was resized
                last_hidden: 0,             // the time the chart was hidden
                last_unhidden: 0,           // the time the chart was unhidden
                last_autorefreshed: 0       // the time the chart was last refreshed
            };

            that.data = null;               // the last data as downloaded from the netdata server
            that.data_url = 'invalid://';   // string - the last url used to update the chart
            that.data_points = 0;           // number - the number of points returned from netdata
            that.data_after = 0;            // milliseconds - the first timestamp of the data
            that.data_before = 0;           // milliseconds - the last timestamp of the data
            that.data_update_every = 0;     // milliseconds - the frequency to update the data

            that.tm.last_initialized = new Date().getTime();
            createDOM();

            that.setMode('auto');
        };

        var maxMessageFontSize = function() {
            // normally we want a font size, as tall as the element
            var h = that.element_message.clientHeight;

            // but give it some air, 20% let's say, or 5 pixels min
            var lost = Math.max(h * 0.2, 5);
            h -= lost;

            // center the text, vertically
            var paddingTop = (lost - 5) / 2;

            // but check the width too
            // it should fit 10 characters in it
            var w = that.element_message.clientWidth / 10;
            if(h > w) {
                paddingTop += (h - w) / 2;
                h = w;
            }

            // and don't make it too huge
            // 5% of the screen size is good
            if(h > screen.height / 20) {
                paddingTop += (h - (screen.height / 20)) / 2;
                h = screen.height / 20;
            }

            // set it
            that.element_message.style.fontSize = h.toString() + 'px';
            that.element_message.style.paddingTop = paddingTop.toString() + 'px';
        };

        var showMessage = function(msg) {
            that.element_message.className = 'netdata-message';
            that.element_message.innerHTML = msg;
            that.element_message.style.fontSize = 'x-small';
            that.element_message.style.paddingTop = '0px';
            that.___messageHidden___ = undefined;
        };

        var showMessageIcon = function(icon) {
            that.element_message.innerHTML = icon;
            that.element_message.className = 'netdata-message icon';
            maxMessageFontSize();
            that.___messageHidden___ = undefined;
        };

        var hideMessage = function() {
            if(typeof that.___messageHidden___ === 'undefined') {
                that.___messageHidden___ = true;
                that.element_message.className = 'netdata-message hidden';
            }
        };

        var showRendering = function() {
            var icon;
            if(that.chart !== null) {
                if(that.chart.chart_type === 'line')
                    icon = '<i class="fa fa-line-chart"></i>';
                else
                    icon = '<i class="fa fa-area-chart"></i>';
            }
            else
                icon = '<i class="fa fa-area-chart"></i>';

            showMessageIcon(icon + ' netdata');
        };

        var showLoading = function() {
            if(that.chart_created === false) {
                showMessageIcon('<i class="fa fa-refresh"></i> netdata');
                return true;
            }
            return false;
        };

        var isHidden = function() {
            if(typeof that.___chartIsHidden___ !== 'undefined')
                return true;

            return false;
        };

        // hide the chart, when it is not visible - called from isVisible()
        var hideChart = function() {
            // hide it, if it is not already hidden
            if(isHidden() === true) return;

            if(that.chart_created === true) {
                if(NETDATA.options.current.destroy_on_hide === true) {
                    // we should destroy it
                    init();
                }
                else {
                    showRendering();
                    that.element_chart.style.display = 'none';
                    if(that.element_legend !== null) that.element_legend.style.display = 'none';
                    that.tm.last_hidden = new Date().getTime();

                    // de-allocate data
                    // This works, but I not sure there are no corner cases somewhere
                    // so it is commented - if the user has memory issues he can
                    // set Destroy on Hide for all charts
                    // that.data = null;
                }
            }

            that.___chartIsHidden___ = true;
        };

        // unhide the chart, when it is visible - called from isVisible()
        var unhideChart = function() {
            if(isHidden() === false) return;

            that.___chartIsHidden___ = undefined;
            that.updates_since_last_unhide = 0;

            if(that.chart_created === false) {
                // we need to re-initialize it, to show our background
                // logo in bootstrap tabs, until the chart loads
                init();
            }
            else {
                that.tm.last_unhidden = new Date().getTime();
                that.element_chart.style.display = '';
                if(that.element_legend !== null) that.element_legend.style.display = '';
                resizeChart();
                hideMessage();
            }
        };

        var canBeRendered = function() {
            if(isHidden() === true || that.isVisible(true) === false)
                return false;

            return true;
        };

        // https://github.com/petkaantonov/bluebird/wiki/Optimization-killers
        var callChartLibraryUpdateSafely = function(data) {
            var status;

            if(canBeRendered() === false)
                return false;

            if(NETDATA.options.debug.chart_errors === true)
                status = that.library.update(that, data);
            else {
                try {
                    status = that.library.update(that, data);
                }
                catch(err) {
                    status = false;
                }
            }

            if(status === false) {
                error('chart failed to be updated as ' + that.library_name);
                return false;
            }

            return true;
        };

        // https://github.com/petkaantonov/bluebird/wiki/Optimization-killers
        var callChartLibraryCreateSafely = function(data) {
            var status;

            if(canBeRendered() === false)
                return false;

            if(NETDATA.options.debug.chart_errors === true)
                status = that.library.create(that, data);
            else {
                try {
                    status = that.library.create(that, data);
                }
                catch(err) {
                    status = false;
                }
            }

            if(status === false) {
                error('chart failed to be created as ' + that.library_name);
                return false;
            }

            that.chart_created = true;
            that.updates_since_last_creation = 0;
            return true;
        };

        // ----------------------------------------------------------------------------------------------------------------
        // Chart Resize

        // resizeChart() - private
        // to be called just before the chart library to make sure that
        // a properly sized dom is available
        var resizeChart = function() {
            if(that.isVisible() === true && that.tm.last_resized < NETDATA.options.last_resized) {
                if(that.chart_created === false) return;

                if(that.needsRecreation()) {
                    init();
                }
                else if(typeof that.library.resize === 'function') {
                    that.library.resize(that);

                    if(that.element_legend_childs.nano !== null && that.element_legend_childs.nano_options !== null)
                        $(that.element_legend_childs.nano).nanoScroller();

                    maxMessageFontSize();
                }

                that.tm.last_resized = new Date().getTime();
            }
        };

        // this is the actual chart resize algorithm
        // it will:
        // - resize the entire container
        // - update the internal states
        // - resize the chart as the div changes height
        // - update the scrollbar of the legend
        var resizeChartToHeight = function(h) {
            // console.log(h);
            that.element.style.height = h;

            if(that.settings_id !== null)
                NETDATA.localStorageSet('chart_heights.' + that.settings_id, h);

            var now = new Date().getTime();
            NETDATA.options.last_page_scroll = now;
            NETDATA.options.auto_refresher_stop_until = now + NETDATA.options.current.stop_updates_while_resizing;

            // force a resize
            that.tm.last_resized = 0;
            resizeChart();
        };

        this.resizeHandler = function(e) {
            e.preventDefault();

            if(typeof this.event_resize === 'undefined'
                || this.event_resize.chart_original_w === 'undefined'
                || this.event_resize.chart_original_h === 'undefined')
                this.event_resize = {
                    chart_original_w: this.element.clientWidth,
                    chart_original_h: this.element.clientHeight,
                    last: 0
                };

            if(e.type === 'touchstart') {
                this.event_resize.mouse_start_x = e.touches.item(0).pageX;
                this.event_resize.mouse_start_y = e.touches.item(0).pageY;
            }
            else {
                this.event_resize.mouse_start_x = e.clientX;
                this.event_resize.mouse_start_y = e.clientY;
            }

            this.event_resize.chart_start_w = this.element.clientWidth;
            this.event_resize.chart_start_h = this.element.clientHeight;
            this.event_resize.chart_last_w = this.element.clientWidth;
            this.event_resize.chart_last_h = this.element.clientHeight;

            var now = new Date().getTime();
            if(now - this.event_resize.last <= NETDATA.options.current.double_click_speed) {
                // double click / double tap event

                // the optimal height of the chart
                // showing the entire legend
                var optimal = this.event_resize.chart_last_h
                        + this.element_legend_childs.content.scrollHeight
                        - this.element_legend_childs.content.clientHeight;

                // if we are not optimal, be optimal
                if(this.event_resize.chart_last_h != optimal)
                    resizeChartToHeight(optimal.toString() + 'px');

                // else if we do not have the original height
                // reset to the original height
                else if(this.event_resize.chart_last_h != this.event_resize.chart_original_h)
                    resizeChartToHeight(this.event_resize.chart_original_h.toString() + 'px');
            }
            else {
                this.event_resize.last = now;

                // process movement event
                document.onmousemove =
                document.ontouchmove =
                this.element_legend_childs.resize_handler.onmousemove =
                this.element_legend_childs.resize_handler.ontouchmove =
                    function(e) {
                        var y = null;

                        switch(e.type) {
                            case 'mousemove': y = e.clientY; break;
                            case 'touchmove': y = e.touches.item(e.touches - 1).pageY; break;
                        }

                        if(y !== null) {
                            var newH = that.event_resize.chart_start_h + y - that.event_resize.mouse_start_y;

                            if(newH >= 70 && newH !== that.event_resize.chart_last_h) {
                                resizeChartToHeight(newH.toString() + 'px');
                                that.event_resize.chart_last_h = newH;
                            }
                        }
                    };

                // process end event
                document.onmouseup =
                document.ontouchend =
                this.element_legend_childs.resize_handler.onmouseup =
                this.element_legend_childs.resize_handler.ontouchend =
                    function(e) {
                        // remove all the hooks
                        document.onmouseup =
                        document.onmousemove =
                        document.ontouchmove =
                        document.ontouchend =
                        that.element_legend_childs.resize_handler.onmousemove =
                        that.element_legend_childs.resize_handler.ontouchmove =
                        that.element_legend_childs.resize_handler.onmouseout =
                        that.element_legend_childs.resize_handler.onmouseup =
                        that.element_legend_childs.resize_handler.ontouchend =
                            null;

                        // allow auto-refreshes
                        NETDATA.options.auto_refresher_stop_until = 0;
                    };
            }
        };


        var noDataToShow = function() {
            showMessageIcon('<i class="fa fa-warning"></i> empty');
            that.legendUpdateDOM();
            that.tm.last_autorefreshed = new Date().getTime();
            // that.data_update_every = 30 * 1000;
            //that.element_chart.style.display = 'none';
            //if(that.element_legend !== null) that.element_legend.style.display = 'none';
            //that.___chartIsHidden___ = true;
        };

        // ============================================================================================================
        // PUBLIC FUNCTIONS

        this.error = function(msg) {
            error(msg);
        };

        this.setMode = function(m) {
            if(this.current !== null && this.current.name === m) return;

            if(m === 'auto')
                this.current = this.auto;
            else if(m === 'pan')
                this.current = this.pan;
            else if(m === 'zoom')
                this.current = this.zoom;
            else
                this.current = this.auto;

            this.current.force_update_at = 0;
            this.current.force_before_ms = null;
            this.current.force_after_ms = null;

            this.tm.last_mode_switch = new Date().getTime();
        };

        // ----------------------------------------------------------------------------------------------------------------
        // global selection sync

        // prevent to global selection sync for some time
        this.globalSelectionSyncDelay = function(ms) {
            if(NETDATA.options.current.sync_selection === false)
                return;

            if(typeof ms === 'number')
                NETDATA.globalSelectionSync.dont_sync_before = new Date().getTime() + ms;
            else
                NETDATA.globalSelectionSync.dont_sync_before = new Date().getTime() + NETDATA.options.current.sync_selection_delay;
        };

        // can we globally apply selection sync?
        this.globalSelectionSyncAbility = function() {
            if(NETDATA.options.current.sync_selection === false)
                return false;

            if(NETDATA.globalSelectionSync.dont_sync_before > new Date().getTime())
                return false;

            return true;
        };

        this.globalSelectionSyncIsMaster = function() {
            if(NETDATA.globalSelectionSync.state === this)
                return true;
            else
                return false;
        };

        // this chart is the master of the global selection sync
        this.globalSelectionSyncBeMaster = function() {
            // am I the master?
            if(this.globalSelectionSyncIsMaster()) {
                if(this.debug === true)
                    this.log('sync: I am the master already.');

                return;
            }

            if(NETDATA.globalSelectionSync.state) {
                if(this.debug === true)
                    this.log('sync: I am not the sync master. Resetting global sync.');

                this.globalSelectionSyncStop();
            }

            // become the master
            if(this.debug === true)
                this.log('sync: becoming sync master.');

            this.selected = true;
            NETDATA.globalSelectionSync.state = this;

            // find the all slaves
            var targets = NETDATA.options.targets;
            var len = targets.length;
            while(len--) {
                st = targets[len];

                if(st === this) {
                    if(this.debug === true)
                        st.log('sync: not adding me to sync');
                }
                else if(st.globalSelectionSyncIsEligible()) {
                    if(this.debug === true)
                        st.log('sync: adding to sync as slave');

                    st.globalSelectionSyncBeSlave();
                }
            }

            // this.globalSelectionSyncDelay(100);
        };

        // can the chart participate to the global selection sync as a slave?
        this.globalSelectionSyncIsEligible = function() {
            if(this.enabled === true
                && this.library !== null
                && typeof this.library.setSelection === 'function'
                && this.isVisible() === true
                && this.chart_created === true)
                return true;

            return false;
        };

        // this chart becomes a slave of the global selection sync
        this.globalSelectionSyncBeSlave = function() {
            if(NETDATA.globalSelectionSync.state !== this)
                NETDATA.globalSelectionSync.slaves.push(this);
        };

        // sync all the visible charts to the given time
        // this is to be called from the chart libraries
        this.globalSelectionSync = function(t) {
            if(this.globalSelectionSyncAbility() === false) {
                if(this.debug === true)
                    this.log('sync: cannot sync (yet?).');

                return;
            }

            if(this.globalSelectionSyncIsMaster() === false) {
                if(this.debug === true)
                    this.log('sync: trying to be sync master.');

                this.globalSelectionSyncBeMaster();

                if(this.globalSelectionSyncAbility() === false) {
                    if(this.debug === true)
                        this.log('sync: cannot sync (yet?).');

                    return;
                }
            }

            NETDATA.globalSelectionSync.last_t = t;
            $.each(NETDATA.globalSelectionSync.slaves, function(i, st) {
                st.setSelection(t);
            });
        };

        // stop syncing all charts to the given time
        this.globalSelectionSyncStop = function() {
            if(NETDATA.globalSelectionSync.slaves.length) {
                if(this.debug === true)
                    this.log('sync: cleaning up...');

                $.each(NETDATA.globalSelectionSync.slaves, function(i, st) {
                    if(st === that) {
                        if(that.debug === true)
                            st.log('sync: not adding me to sync stop');
                    }
                    else {
                        if(that.debug === true)
                            st.log('sync: removed slave from sync');

                        st.clearSelection();
                    }
                });

                NETDATA.globalSelectionSync.last_t = 0;
                NETDATA.globalSelectionSync.slaves = [];
                NETDATA.globalSelectionSync.state = null;
            }

            this.clearSelection();
        };

        this.setSelection = function(t) {
            if(typeof this.library.setSelection === 'function') {
                if(this.library.setSelection(this, t) === true)
                    this.selected = true;
                else
                    this.selected = false;
            }
            else this.selected = true;

            if(this.selected === true && this.debug === true)
                this.log('selection set to ' + t.toString());

            return this.selected;
        };

        this.clearSelection = function() {
            if(this.selected === true) {
                if(typeof this.library.clearSelection === 'function') {
                    if(this.library.clearSelection(this) === true)
                        this.selected = false;
                    else
                        this.selected = true;
                }
                else this.selected = false;

                if(this.selected === false && this.debug === true)
                    this.log('selection cleared');

                this.legendReset();
            }

            return this.selected;
        };

        // find if a timestamp (ms) is shown in the current chart
        this.timeIsVisible = function(t) {
            if(t >= this.data_after && t <= this.data_before)
                return true;
            return false;
        };

        this.calculateRowForTime = function(t) {
            if(this.timeIsVisible(t) === false) return -1;
            return Math.floor((t - this.data_after) / this.data_update_every);
        };

        // ----------------------------------------------------------------------------------------------------------------

        // console logging
        this.log = function(msg) {
            console.log(this.id + ' (' + this.library_name + ' ' + this.uuid + '): ' + msg);
        };

        this.pauseChart = function() {
            if(this.paused === false) {
                if(this.debug === true)
                    this.log('pauseChart()');

                this.paused = true;
            }
        };

        this.unpauseChart = function() {
            if(this.paused === true) {
                if(this.debug === true)
                    this.log('unpauseChart()');

                this.paused = false;
            }
        };

        this.resetChart = function(dont_clear_master, dont_update) {
            if(this.debug === true)
                this.log('resetChart(' + dont_clear_master + ', ' + dont_update + ') called');

            if(typeof dont_clear_master === 'undefined')
                dont_clear_master = false;

            if(typeof dont_update === 'undefined')
                dont_update = false;

            if(dont_clear_master !== true && NETDATA.globalPanAndZoom.isMaster(this) === true) {
                if(this.debug === true)
                    this.log('resetChart() diverting to clearMaster().');
                // this will call us back with master === true
                NETDATA.globalPanAndZoom.clearMaster();
                return;
            }

            this.clearSelection();

            this.tm.pan_and_zoom_seq = 0;

            this.setMode('auto');
            this.current.force_update_at = 0;
            this.current.force_before_ms = null;
            this.current.force_after_ms = null;
            this.tm.last_autorefreshed = 0;
            this.paused = false;
            this.selected = false;
            this.enabled = true;
            // this.debug = false;

            // do not update the chart here
            // or the chart will flip-flop when it is the master
            // of a selection sync and another chart becomes
            // the new master

            if(dont_update !== true && this.isVisible() === true) {
                this.updateChart();
            }
        };

        this.updateChartPanOrZoom = function(after, before) {
            var logme = 'updateChartPanOrZoom(' + after + ', ' + before + '): ';
            var ret = true;

            if(this.debug === true)
                this.log(logme);

            if(before < after) {
                if(this.debug === true)
                    this.log(logme + 'flipped parameters, rejecting it.');

                return false;
            }

            if(typeof this.fixed_min_duration === 'undefined')
                this.fixed_min_duration = Math.round((this.chartWidth() / 30) * this.chart.update_every * 1000);

            var min_duration = this.fixed_min_duration;
            var current_duration = Math.round(this.view_before - this.view_after);

            // round the numbers
            after = Math.round(after);
            before = Math.round(before);

            // align them to update_every
            // stretching them further away
            after -= after % this.data_update_every;
            before += this.data_update_every - (before % this.data_update_every);

            // the final wanted duration
            var wanted_duration = before - after;

            // to allow panning, accept just a point below our minimum
            if((current_duration - this.data_update_every) < min_duration)
                min_duration = current_duration - this.data_update_every;

            // we do it, but we adjust to minimum size and return false
            // when the wanted size is below the current and the minimum
            // and we zoom
            if(wanted_duration < current_duration && wanted_duration < min_duration) {
                if(this.debug === true)
                    this.log(logme + 'too small: min_duration: ' + (min_duration / 1000).toString() + ', wanted: ' + (wanted_duration / 1000).toString());

                min_duration = this.fixed_min_duration;

                var dt = (min_duration - wanted_duration) / 2;
                before += dt;
                after -= dt;
                wanted_duration = before - after;
                ret = false;
            }

            var tolerance = this.data_update_every * 2;
            var movement = Math.abs(before - this.view_before);

            if(Math.abs(current_duration - wanted_duration) <= tolerance && movement <= tolerance && ret === true) {
                if(this.debug === true)
                    this.log(logme + 'REJECTING UPDATE: current/min duration: ' + (current_duration / 1000).toString() + '/' + (this.fixed_min_duration / 1000).toString() + ', wanted duration: ' + (wanted_duration / 1000).toString() + ', duration diff: ' + (Math.round(Math.abs(current_duration - wanted_duration) / 1000)).toString() + ', movement: ' + (movement / 1000).toString() + ', tolerance: ' + (tolerance / 1000).toString() + ', returning: ' + false);
                return false;
            }

            if(this.current.name === 'auto') {
                this.log(logme + 'caller called me with mode: ' + this.current.name);
                this.setMode('pan');
            }

            if(this.debug === true)
                this.log(logme + 'ACCEPTING UPDATE: current/min duration: ' + (current_duration / 1000).toString() + '/' + (this.fixed_min_duration / 1000).toString() + ', wanted duration: ' + (wanted_duration / 1000).toString() + ', duration diff: ' + (Math.round(Math.abs(current_duration - wanted_duration) / 1000)).toString() + ', movement: ' + (movement / 1000).toString() + ', tolerance: ' + (tolerance / 1000).toString() + ', returning: ' + ret);

            this.current.force_update_at = new Date().getTime() + NETDATA.options.current.pan_and_zoom_delay;
            this.current.force_after_ms = after;
            this.current.force_before_ms = before;
            NETDATA.globalPanAndZoom.setMaster(this, after, before);
            return ret;
        };

        this.legendFormatValue = function(value) {
            if(value === null || value === 'undefined') return '-';
            if(typeof value !== 'number') return value;

            var abs = Math.abs(value);
            if(abs >= 1000) return (Math.round(value)).toLocaleString();
            if(abs >= 100 ) return (Math.round(value * 10) / 10).toLocaleString();
            if(abs >= 1   ) return (Math.round(value * 100) / 100).toLocaleString();
            if(abs >= 0.1 ) return (Math.round(value * 1000) / 1000).toLocaleString();
            return (Math.round(value * 10000) / 10000).toLocaleString();
        };

        this.legendSetLabelValue = function(label, value) {
            var series = this.element_legend_childs.series[label];
            if(typeof series === 'undefined') return;
            if(series.value === null && series.user === null) return;

            // if the value has not changed, skip DOM update
            //if(series.last === value) return;

            var s, r;
            if(typeof value === 'number') {
                var v = Math.abs(value);
                s = r = this.legendFormatValue(value);

                if(typeof series.last === 'number') {
                    if(v > series.last) s += '<i class="fa fa-angle-up" style="width: 8px; text-align: center; overflow: hidden; vertical-align: middle;"></i>';
                    else if(v < series.last) s += '<i class="fa fa-angle-down" style="width: 8px; text-align: center; overflow: hidden; vertical-align: middle;"></i>';
                    else s += '<i class="fa fa-angle-left" style="width: 8px; text-align: center; overflow: hidden; vertical-align: middle;"></i>';
                }
                else s += '<i class="fa fa-angle-right" style="width: 8px; text-align: center; overflow: hidden; vertical-align: middle;"></i>';
                series.last = v;
            }
            else {
                s = r = value;
                series.last = value;
            }

            if(series.value !== null) series.value.innerHTML = s;
            if(series.user !== null) series.user.innerHTML = r;
        };

        this.legendSetDate = function(ms) {
            if(typeof ms !== 'number') {
                this.legendShowUndefined();
                return;
            }

            var d = new Date(ms);

            if(this.element_legend_childs.title_date)
                this.element_legend_childs.title_date.innerHTML = d.toLocaleDateString();

            if(this.element_legend_childs.title_time)
                this.element_legend_childs.title_time.innerHTML = d.toLocaleTimeString();

            if(this.element_legend_childs.title_units)
                this.element_legend_childs.title_units.innerHTML = this.units;
        };

        this.legendShowUndefined = function() {
            if(this.element_legend_childs.title_date)
                this.element_legend_childs.title_date.innerHTML = '&nbsp;';

            if(this.element_legend_childs.title_time)
                this.element_legend_childs.title_time.innerHTML = this.chart.name;

            if(this.element_legend_childs.title_units)
                this.element_legend_childs.title_units.innerHTML = '&nbsp;';

            if(this.data && this.element_legend_childs.series !== null) {
                var labels = this.data.dimension_names;
                var i = labels.length;
                while(i--) {
                    var label = labels[i];

                    if(typeof label === 'undefined') continue;
                    if(typeof this.element_legend_childs.series[label] === 'undefined') continue;
                    this.legendSetLabelValue(label, null);
                }
            }
        };

        this.legendShowLatestValues = function() {
            if(this.chart === null) return;
            if(this.selected) return;

            if(this.data === null || this.element_legend_childs.series === null) {
                this.legendShowUndefined();
                return;
            }

            var show_undefined = true;
            if(Math.abs(this.netdata_last - this.view_before) <= this.data_update_every)
                show_undefined = false;

            if(show_undefined) {
                this.legendShowUndefined();
                return;
            }

            this.legendSetDate(this.view_before);

            var labels = this.data.dimension_names;
            var i = labels.length;
            while(i--) {
                var label = labels[i];

                if(typeof label === 'undefined') continue;
                if(typeof this.element_legend_childs.series[label] === 'undefined') continue;

                if(show_undefined)
                    this.legendSetLabelValue(label, null);
                else
                    this.legendSetLabelValue(label, this.data.view_latest_values[i]);
            }
        };

        this.legendReset = function() {
            this.legendShowLatestValues();
        };

        // this should be called just ONCE per dimension per chart
        this._chartDimensionColor = function(label) {
            if(this.colors === null) this.chartColors();

            if(typeof this.colors_assigned[label] === 'undefined') {
                if(this.colors_available.length === 0) {
                    for(var i = 0, len = NETDATA.themes.current.colors.length; i < len ; i++)
                        this.colors_available.push(NETDATA.themes.current.colors[i]);
                }

                this.colors_assigned[label] = this.colors_available.shift();

                if(this.debug === true)
                    this.log('label "' + label + '" got color "' + this.colors_assigned[label]);
            }
            else {
                if(this.debug === true)
                    this.log('label "' + label + '" already has color "' + this.colors_assigned[label] + '"');
            }

            this.colors.push(this.colors_assigned[label]);
            return this.colors_assigned[label];
        };

        this.chartColors = function() {
            if(this.colors !== null) return this.colors;

            this.colors = new Array();
            this.colors_available = new Array();
            var i, len;

            var c = $(this.element).data('colors');
            // this.log('read colors: ' + c);
            if(typeof c !== 'undefined' && c !== null && c.length > 0) {
                if(typeof c !== 'string') {
                    this.log('invalid color given: ' + c + ' (give a space separated list of colors)');
                }
                else {
                    c = c.split(' ');
                    var added = 0;

                    while(added < 20) {
                        for(i = 0, len = c.length; i < len ; i++) {
                            added++;
                            this.colors_available.push(c[i]);
                            // this.log('adding color: ' + c[i]);
                        }
                    }
                }
            }

            // push all the standard colors too
            for(i = 0, len = NETDATA.themes.current.colors.length; i < len ; i++)
                this.colors_available.push(NETDATA.themes.current.colors[i]);

            return this.colors;
        };

        this.legendUpdateDOM = function() {
            var needed = false;

            // check that the legend DOM is up to date for the downloaded dimensions
            if(typeof this.element_legend_childs.series !== 'object' || this.element_legend_childs.series === null) {
                // this.log('the legend does not have any series - requesting legend update');
                needed = true;
            }
            else if(this.data === null) {
                // this.log('the chart does not have any data - requesting legend update');
                needed = true;
            }
            else if(typeof this.element_legend_childs.series.labels_key === 'undefined') {
                needed = true;
            }
            else {
                var labels = this.data.dimension_names.toString();
                if(labels !== this.element_legend_childs.series.labels_key) {
                    needed = true;

                    if(this.debug === true)
                        this.log('NEW LABELS: "' + labels + '" NOT EQUAL OLD LABELS: "' + this.element_legend_childs.series.labels_key + '"');
                }
            }

            if(needed === false) {
                // make sure colors available
                this.chartColors();

                // do we have to update the current values?
                // we do this, only when the visible chart is current
                if(Math.abs(this.netdata_last - this.view_before) <= this.data_update_every) {
                    if(this.debug === true)
                        this.log('chart is in latest position... updating values on legend...');

                    //var labels = this.data.dimension_names;
                    //var i = labels.length;
                    //while(i--)
                    //  this.legendSetLabelValue(labels[i], this.data.latest_values[i]);
                }
                return;
            }
            if(this.colors === null) {
                // this is the first time we update the chart
                // let's assign colors to all dimensions
                if(this.library.track_colors() === true)
                    for(var dim in this.chart.dimensions)
                        this._chartDimensionColor(this.chart.dimensions[dim].name);
            }
            // we will re-generate the colors for the chart
            // based on the selected dimensions
            this.colors = null;

            if(this.debug === true)
                this.log('updating Legend DOM');

            // mark all dimensions as invalid
            this.dimensions_visibility.invalidateAll();

            var genLabel = function(state, parent, dim, name, count) {
                var color = state._chartDimensionColor(name);

                var user_element = null;
                var user_id = self.data('show-value-of-' + dim + '-at') || null;
                if(user_id !== null) {
                    user_element = document.getElementById(user_id) || null;
                    if(user_element === null)
                        state.log('Cannot find element with id: ' + user_id);
                }

                state.element_legend_childs.series[name] = {
                    name: document.createElement('span'),
                    value: document.createElement('span'),
                    user: user_element,
                    last: null
                };

                var label = state.element_legend_childs.series[name];

                // create the dimension visibility tracking for this label
                state.dimensions_visibility.dimensionAdd(name, label.name, label.value, color);

                var rgb = NETDATA.colorHex2Rgb(color);
                label.name.innerHTML = '<table class="netdata-legend-name-table-'
                    + state.chart.chart_type
                    + '" style="background-color: '
                    + 'rgba(' + rgb.r + ',' + rgb.g + ',' + rgb.b + ',' + NETDATA.options.current['color_fill_opacity_' + state.chart.chart_type] + ')'
                    + '"><tr class="netdata-legend-name-tr"><td class="netdata-legend-name-td"></td></tr></table>'

                var text = document.createTextNode(' ' + name);
                label.name.appendChild(text);

                if(count > 0)
                    parent.appendChild(document.createElement('br'));

                parent.appendChild(label.name);
                parent.appendChild(label.value);
            };

            var content = document.createElement('div');

            if(this.hasLegend()) {
                this.element_legend_childs = {
                    content: content,
                    resize_handler: document.createElement('div'),
                    toolbox: document.createElement('div'),
                    toolbox_left: document.createElement('div'),
                    toolbox_right: document.createElement('div'),
                    toolbox_reset: document.createElement('div'),
                    toolbox_zoomin: document.createElement('div'),
                    toolbox_zoomout: document.createElement('div'),
                    toolbox_volume: document.createElement('div'),
                    title_date: document.createElement('span'),
                    title_time: document.createElement('span'),
                    title_units: document.createElement('span'),
                    nano: document.createElement('div'),
                    nano_options: {
                        paneClass: 'netdata-legend-series-pane',
                        sliderClass: 'netdata-legend-series-slider',
                        contentClass: 'netdata-legend-series-content',
                        enabledClass: '__enabled',
                        flashedClass: '__flashed',
                        activeClass: '__active',
                        tabIndex: -1,
                        alwaysVisible: true,
                        sliderMinHeight: 10
                    },
                    series: {}
                };

                this.element_legend.innerHTML = '';

                if(this.library.toolboxPanAndZoom !== null) {

                    function get_pan_and_zoom_step(event) {
                        if (event.ctrlKey)
                            return NETDATA.options.current.pan_and_zoom_factor * NETDATA.options.current.pan_and_zoom_factor_multiplier_control;

                        else if (event.shiftKey)
                            return NETDATA.options.current.pan_and_zoom_factor * NETDATA.options.current.pan_and_zoom_factor_multiplier_shift;

                        else if (event.altKey)
                            return NETDATA.options.current.pan_and_zoom_factor * NETDATA.options.current.pan_and_zoom_factor_multiplier_alt;

                        else
                            return NETDATA.options.current.pan_and_zoom_factor;
                    }

                    this.element_legend_childs.toolbox.className += ' netdata-legend-toolbox';
                    this.element.appendChild(this.element_legend_childs.toolbox);

                    this.element_legend_childs.toolbox_left.className += ' netdata-legend-toolbox-button';
                    this.element_legend_childs.toolbox_left.innerHTML = '<i class="fa fa-backward"></i>';
                    this.element_legend_childs.toolbox.appendChild(this.element_legend_childs.toolbox_left);
                    this.element_legend_childs.toolbox_left.onclick = function(e) {
                        e.preventDefault();

                        var step = (that.view_before - that.view_after) * get_pan_and_zoom_step(e);
                        var before = that.view_before - step;
                        var after = that.view_after - step;
                        if(after >= that.netdata_first)
                            that.library.toolboxPanAndZoom(that, after, before);
                    };
                    if(NETDATA.options.current.show_help === true)
                        $(this.element_legend_childs.toolbox_left).popover({
                        container: "body",
                        animation: false,
                        html: true,
                        trigger: 'hover',
                        placement: 'bottom',
                        delay: { show: NETDATA.options.current.show_help_delay_show_ms, hide: NETDATA.options.current.show_help_delay_hide_ms },
                        title: 'Pan Left',
                        content: 'Pan the chart to the left. You can also <b>drag it</b> with your mouse or your finger (on touch devices).<br/><small>Help, can be disabled from the settings.</small>'
                    });


                    this.element_legend_childs.toolbox_reset.className += ' netdata-legend-toolbox-button';
                    this.element_legend_childs.toolbox_reset.innerHTML = '<i class="fa fa-play"></i>';
                    this.element_legend_childs.toolbox.appendChild(this.element_legend_childs.toolbox_reset);
                    this.element_legend_childs.toolbox_reset.onclick = function(e) {
                        e.preventDefault();
                        NETDATA.resetAllCharts(that);
                    };
                    if(NETDATA.options.current.show_help === true)
                        $(this.element_legend_childs.toolbox_reset).popover({
                        container: "body",
                        animation: false,
                        html: true,
                        trigger: 'hover',
                        placement: 'bottom',
                        delay: { show: NETDATA.options.current.show_help_delay_show_ms, hide: NETDATA.options.current.show_help_delay_hide_ms },
                        title: 'Chart Reset',
                        content: 'Reset all the charts to their default auto-refreshing state. You can also <b>double click</b> the chart contents with your mouse or your finger (on touch devices).<br/><small>Help, can be disabled from the settings.</small>'
                    });
                    
                    this.element_legend_childs.toolbox_right.className += ' netdata-legend-toolbox-button';
                    this.element_legend_childs.toolbox_right.innerHTML = '<i class="fa fa-forward"></i>';
                    this.element_legend_childs.toolbox.appendChild(this.element_legend_childs.toolbox_right);
                    this.element_legend_childs.toolbox_right.onclick = function(e) {
                        e.preventDefault();
                        var step = (that.view_before - that.view_after) * get_pan_and_zoom_step(e);
                        var before = that.view_before + step;
                        var after = that.view_after + step;
                        if(before <= that.netdata_last)
                            that.library.toolboxPanAndZoom(that, after, before);
                    };
                    if(NETDATA.options.current.show_help === true)
                        $(this.element_legend_childs.toolbox_right).popover({
                        container: "body",
                        animation: false,
                        html: true,
                        trigger: 'hover',
                        placement: 'bottom',
                        delay: { show: NETDATA.options.current.show_help_delay_show_ms, hide: NETDATA.options.current.show_help_delay_hide_ms },
                        title: 'Pan Right',
                        content: 'Pan the chart to the right. You can also <b>drag it</b> with your mouse or your finger (on touch devices).<br/><small>Help, can be disabled from the settings.</small>'
                    });

                    
                    this.element_legend_childs.toolbox_zoomin.className += ' netdata-legend-toolbox-button';
                    this.element_legend_childs.toolbox_zoomin.innerHTML = '<i class="fa fa-plus"></i>';
                    this.element_legend_childs.toolbox.appendChild(this.element_legend_childs.toolbox_zoomin);
                    this.element_legend_childs.toolbox_zoomin.onclick = function(e) {
                        e.preventDefault();
                        var dt = ((that.view_before - that.view_after) * (get_pan_and_zoom_step(e) * 0.8) / 2);
                        var before = that.view_before - dt;
                        var after = that.view_after + dt;
                        that.library.toolboxPanAndZoom(that, after, before);
                    };
                    if(NETDATA.options.current.show_help === true)
                        $(this.element_legend_childs.toolbox_zoomin).popover({
                        container: "body",
                        animation: false,
                        html: true,
                        trigger: 'hover',
                        placement: 'bottom',
                        delay: { show: NETDATA.options.current.show_help_delay_show_ms, hide: NETDATA.options.current.show_help_delay_hide_ms },
                        title: 'Chart Zoom In',
                        content: 'Zoom in the chart. You can also press SHIFT and select an area of the chart to zoom in. On Chrome and Opera, you can press the SHIFT or the ALT keys and then use the mouse wheel to zoom in or out.<br/><small>Help, can be disabled from the settings.</small>'
                    });
                    
                    this.element_legend_childs.toolbox_zoomout.className += ' netdata-legend-toolbox-button';
                    this.element_legend_childs.toolbox_zoomout.innerHTML = '<i class="fa fa-minus"></i>';
                    this.element_legend_childs.toolbox.appendChild(this.element_legend_childs.toolbox_zoomout);
                    this.element_legend_childs.toolbox_zoomout.onclick = function(e) {
                        e.preventDefault();
                        var dt = (((that.view_before - that.view_after) / (1.0 - (get_pan_and_zoom_step(e) * 0.8)) - (that.view_before - that.view_after)) / 2);
                        var before = that.view_before + dt;
                        var after = that.view_after - dt;

                        that.library.toolboxPanAndZoom(that, after, before);
                    };
                    if(NETDATA.options.current.show_help === true)
                        $(this.element_legend_childs.toolbox_zoomout).popover({
                        container: "body",
                        animation: false,
                        html: true,
                        trigger: 'hover',
                        placement: 'bottom',
                        delay: { show: NETDATA.options.current.show_help_delay_show_ms, hide: NETDATA.options.current.show_help_delay_hide_ms },
                        title: 'Chart Zoom Out',
                        content: 'Zoom out the chart. On Chrome and Opera, you can also press the SHIFT or the ALT keys and then use the mouse wheel to zoom in or out.<br/><small>Help, can be disabled from the settings.</small>'
                    });
                    
                    //this.element_legend_childs.toolbox_volume.className += ' netdata-legend-toolbox-button';
                    //this.element_legend_childs.toolbox_volume.innerHTML = '<i class="fa fa-sort-amount-desc"></i>';
                    //this.element_legend_childs.toolbox_volume.title = 'Visible Volume';
                    //this.element_legend_childs.toolbox.appendChild(this.element_legend_childs.toolbox_volume);
                    //this.element_legend_childs.toolbox_volume.onclick = function(e) {
                        //e.preventDefault();
                        //alert('clicked toolbox_volume on ' + that.id);
                    //}
                }
                else {
                    this.element_legend_childs.toolbox = null;
                    this.element_legend_childs.toolbox_left = null;
                    this.element_legend_childs.toolbox_reset = null;
                    this.element_legend_childs.toolbox_right = null;
                    this.element_legend_childs.toolbox_zoomin = null;
                    this.element_legend_childs.toolbox_zoomout = null;
                    this.element_legend_childs.toolbox_volume = null;
                }
                
                this.element_legend_childs.resize_handler.className += " netdata-legend-resize-handler";
                this.element_legend_childs.resize_handler.innerHTML = '<i class="fa fa-chevron-up"></i><i class="fa fa-chevron-down"></i>';
                this.element.appendChild(this.element_legend_childs.resize_handler);
                if(NETDATA.options.current.show_help === true)
                    $(this.element_legend_childs.resize_handler).popover({
                    container: "body",
                    animation: false,
                    html: true,
                    trigger: 'hover',
                    placement: 'bottom',
                    delay: { show: NETDATA.options.current.show_help_delay_show_ms, hide: NETDATA.options.current.show_help_delay_hide_ms },
                    title: 'Chart Resize',
                    content: 'Drag this point with your mouse or your finger (on touch devices), to resize the chart vertically. You can also <b>double click it</b> or <b>double tap it</b> to reset between 2 states: the default and the one that fits all the values.<br/><small>Help, can be disabled from the settings.</small>'
                });

                // mousedown event
                this.element_legend_childs.resize_handler.onmousedown =
                    function(e) {
                        that.resizeHandler(e);
                    };

                // touchstart event
                this.element_legend_childs.resize_handler.addEventListener('touchstart', function(e) {
                    that.resizeHandler(e);
                }, false);

                this.element_legend_childs.title_date.className += " netdata-legend-title-date";
                this.element_legend.appendChild(this.element_legend_childs.title_date);

                this.element_legend.appendChild(document.createElement('br'));

                this.element_legend_childs.title_time.className += " netdata-legend-title-time";
                this.element_legend.appendChild(this.element_legend_childs.title_time);

                this.element_legend.appendChild(document.createElement('br'));

                this.element_legend_childs.title_units.className += " netdata-legend-title-units";
                this.element_legend.appendChild(this.element_legend_childs.title_units);

                this.element_legend.appendChild(document.createElement('br'));

                this.element_legend_childs.nano.className = 'netdata-legend-series';
                this.element_legend.appendChild(this.element_legend_childs.nano);

                content.className = 'netdata-legend-series-content';
                this.element_legend_childs.nano.appendChild(content);

                if(NETDATA.options.current.show_help === true)
                    $(content).popover({
                    container: "body",
                    animation: false,
                    html: true,
                    trigger: 'hover',
                    placement: 'bottom',
                    title: 'Chart Legend',
                    delay: { show: NETDATA.options.current.show_help_delay_show_ms, hide: NETDATA.options.current.show_help_delay_hide_ms },
                    content: 'You can click or tap on the values or the labels to select dimentions. By pressing SHIFT or CONTROL, you can enable or disable multiple dimensions.<br/><small>Help, can be disabled from the settings.</small>'
                });
            }
            else {
                this.element_legend_childs = {
                    content: content,
                    resize_handler: null,
                    toolbox: null,
                    toolbox_left: null,
                    toolbox_right: null,
                    toolbox_reset: null,
                    toolbox_zoomin: null,
                    toolbox_zoomout: null,
                    toolbox_volume: null,
                    title_date: null,
                    title_time: null,
                    title_units: null,
                    nano: null,
                    nano_options: null,
                    series: {}
                };
            }

            if(this.data) {
                this.element_legend_childs.series.labels_key = this.data.dimension_names.toString();
                if(this.debug === true)
                    this.log('labels from data: "' + this.element_legend_childs.series.labels_key + '"');

                for(var i = 0, len = this.data.dimension_names.length; i < len ;i++) {
                    genLabel(this, content, this.data.dimension_ids[i], this.data.dimension_names[i], i);
                }
            }
            else {
                var tmp = new Array();
                for(var dim in this.chart.dimensions) {
                    tmp.push(this.chart.dimensions[dim].name);
                    genLabel(this, content, dim, this.chart.dimensions[dim].name, i);
                }
                this.element_legend_childs.series.labels_key = tmp.toString();
                if(this.debug === true)
                    this.log('labels from chart: "' + this.element_legend_childs.series.labels_key + '"');
            }

            // create a hidden div to be used for hidding
            // the original legend of the chart library
            var el = document.createElement('div');
            if(this.element_legend !== null)
                this.element_legend.appendChild(el);
            el.style.display = 'none';

            this.element_legend_childs.hidden = document.createElement('div');
            el.appendChild(this.element_legend_childs.hidden);

            if(this.element_legend_childs.nano !== null && this.element_legend_childs.nano_options !== null)
                $(this.element_legend_childs.nano).nanoScroller(this.element_legend_childs.nano_options);

            this.legendShowLatestValues();
        };

        this.hasLegend = function() {
            if(typeof this.___hasLegendCache___ !== 'undefined')
                return this.___hasLegendCache___;

            var leg = false;
            if(this.library && this.library.legend(this) === 'right-side') {
                var legend = $(this.element).data('legend') || 'yes';
                if(legend === 'yes') leg = true;
            }

            this.___hasLegendCache___ = leg;
            return leg;
        };

        this.legendWidth = function() {
            return (this.hasLegend())?140:0;
        };

        this.legendHeight = function() {
            return $(this.element).height();
        };

        this.chartWidth = function() {
            return $(this.element).width() - this.legendWidth();
        };

        this.chartHeight = function() {
            return $(this.element).height();
        };

        this.chartPixelsPerPoint = function() {
            // force an options provided detail
            var px = this.pixels_per_point;

            if(this.library && px < this.library.pixels_per_point(this))
                px = this.library.pixels_per_point(this);

            if(px < NETDATA.options.current.pixels_per_point)
                px = NETDATA.options.current.pixels_per_point;

            return px;
        };

        this.needsRecreation = function() {
            return (
                    this.chart_created === true
                    && this.library
                    && this.library.autoresize() === false
                    && this.tm.last_resized < NETDATA.options.last_resized
                );
        };

        this.chartURL = function() {
            var after, before, points_multiplier = 1;
            if(NETDATA.globalPanAndZoom.isActive() && NETDATA.globalPanAndZoom.isMaster(this) === false) {
                this.tm.pan_and_zoom_seq = NETDATA.globalPanAndZoom.seq;

                after = Math.round(NETDATA.globalPanAndZoom.force_after_ms / 1000);
                before = Math.round(NETDATA.globalPanAndZoom.force_before_ms / 1000);
                this.view_after = after * 1000;
                this.view_before = before * 1000;

                this.requested_padding = null;
                points_multiplier = 1;
            }
            else if(this.current.force_before_ms !== null && this.current.force_after_ms !== null) {
                this.tm.pan_and_zoom_seq = 0;

                before = Math.round(this.current.force_before_ms / 1000);
                after  = Math.round(this.current.force_after_ms / 1000);
                this.view_after = after * 1000;
                this.view_before = before * 1000;

                if(NETDATA.options.current.pan_and_zoom_data_padding === true) {
                    this.requested_padding = Math.round((before - after) / 2);
                    after -= this.requested_padding;
                    before += this.requested_padding;
                    this.requested_padding *= 1000;
                    points_multiplier = 2;
                }

                this.current.force_before_ms = null;
                this.current.force_after_ms = null;
            }
            else {
                this.tm.pan_and_zoom_seq = 0;

                before = this.before;
                after  = this.after;
                this.view_after = after * 1000;
                this.view_before = before * 1000;

                this.requested_padding = null;
                points_multiplier = 1;
            }

            this.requested_after = after * 1000;
            this.requested_before = before * 1000;

            this.data_points = this.points || Math.round(this.chartWidth() / this.chartPixelsPerPoint());

            // build the data URL
            this.data_url = this.host + this.chart.data_url;
            this.data_url += "&format="  + this.library.format();
            this.data_url += "&points="  + (this.data_points * points_multiplier).toString();
            this.data_url += "&group="   + this.method;
            this.data_url += "&options=" + this.library.options(this);
            this.data_url += '|jsonwrap';

            if(NETDATA.options.current.eliminate_zero_dimensions === true)
                this.data_url += '|nonzero';

            if(this.append_options !== null)
                this.data_url += '|' + this.append_options.toString();

            if(after)
                this.data_url += "&after="  + after.toString();

            if(before)
                this.data_url += "&before=" + before.toString();

            if(this.dimensions)
                this.data_url += "&dimensions=" + this.dimensions;

            if(NETDATA.options.debug.chart_data_url === true || this.debug === true)
                this.log('chartURL(): ' + this.data_url + ' WxH:' + this.chartWidth() + 'x' + this.chartHeight() + ' points: ' + this.data_points + ' library: ' + this.library_name);
        };

        this.redrawChart = function() {
            if(this.data !== null)
                this.updateChartWithData(this.data);
        };

        this.updateChartWithData = function(data) {
            if(this.debug === true)
                this.log('updateChartWithData() called.');

            // this may force the chart to be re-created
            resizeChart();

            this.data = data;
            this.updates_counter++;
            this.updates_since_last_unhide++;
            this.updates_since_last_creation++;

            var started = new Date().getTime();

            // if the result is JSON, find the latest update-every
            this.data_update_every = data.view_update_every * 1000;
            this.data_after = data.after * 1000;
            this.data_before = data.before * 1000;
            this.netdata_first = data.first_entry * 1000;
            this.netdata_last = data.last_entry * 1000;
            this.data_points = data.points;
            data.state = this;

            if(NETDATA.options.current.pan_and_zoom_data_padding === true && this.requested_padding !== null) {
                if(this.view_after < this.data_after) {
                    // console.log('adusting view_after from ' + this.view_after + ' to ' + this.data_after);
                    this.view_after = this.data_after;
                }

                if(this.view_before > this.data_before) {
                    // console.log('adusting view_before from ' + this.view_before + ' to ' + this.data_before);
                    this.view_before = this.data_before;
                }
            }
            else {
                this.view_after = this.data_after;
                this.view_before = this.data_before;
            }

            if(this.debug === true) {
                this.log('UPDATE No ' + this.updates_counter + ' COMPLETED');

                if(this.current.force_after_ms)
                    this.log('STATUS: forced    : ' + (this.current.force_after_ms / 1000).toString() + ' - ' + (this.current.force_before_ms / 1000).toString());
                else
                    this.log('STATUS: forced    : unset');

                this.log('STATUS: requested : ' + (this.requested_after / 1000).toString() + ' - ' + (this.requested_before / 1000).toString());
                this.log('STATUS: downloaded: ' + (this.data_after / 1000).toString() + ' - ' + (this.data_before / 1000).toString());
                this.log('STATUS: rendered  : ' + (this.view_after / 1000).toString() + ' - ' + (this.view_before / 1000).toString());
                this.log('STATUS: points    : ' + (this.data_points).toString());
            }

            if(this.data_points === 0) {
                noDataToShow();
                return;
            }

            if(this.updates_since_last_creation >= this.library.max_updates_to_recreate()) {
                if(this.debug === true)
                    this.log('max updates of ' + this.updates_since_last_creation.toString() + ' reached. Forcing re-generation.');

                this.chart_created = false;
            }

            // check and update the legend
            this.legendUpdateDOM();

            if(this.chart_created === true
                && typeof this.library.update === 'function') {

                if(this.debug === true)
                    this.log('updating chart...');

                if(callChartLibraryUpdateSafely(data) === false)
                    return;
            }
            else {
                if(this.debug === true)
                    this.log('creating chart...');

                if(callChartLibraryCreateSafely(data) === false)
                    return;
            }
            hideMessage();
            this.legendShowLatestValues();
            if(this.selected === true)
                NETDATA.globalSelectionSync.stop();

            // update the performance counters
            var now = new Date().getTime();
            this.tm.last_updated = now;

            // don't update last_autorefreshed if this chart is
            // forced to be updated with global PanAndZoom
            if(NETDATA.globalPanAndZoom.isActive())
                this.tm.last_autorefreshed = 0;
            else {
                if(NETDATA.options.current.parallel_refresher === true && NETDATA.options.current.concurrent_refreshes === true)
                    this.tm.last_autorefreshed = now - (now % this.data_update_every);
                else
                    this.tm.last_autorefreshed = now;
            }

            this.refresh_dt_ms = now - started;
            NETDATA.options.auto_refresher_fast_weight += this.refresh_dt_ms;

            if(this.refresh_dt_element !== null)
                this.refresh_dt_element.innerHTML = this.refresh_dt_ms.toString();
        };

        this.updateChart = function(callback) {
            if(this.debug === true)
                this.log('updateChart() called.');

            if(this._updating === true) {
                if(this.debug === true)
                    this.log('I am already updating...');

                if(typeof callback === 'function') callback();
                return false;
            }

            // due to late initialization of charts and libraries
            // we need to check this too
            if(this.enabled === false) {
                if(this.debug === true)
                    this.log('I am not enabled');

                if(typeof callback === 'function') callback();
                return false;
            }

            if(canBeRendered() === false) {
                if(typeof callback === 'function') callback();
                return false;
            }

            if(this.chart === null) {
                this.getChart(function() { that.updateChart(callback); });
                return false;
            }

            if(this.library.initialized === false) {
                if(this.library.enabled === true) {
                    this.library.initialize(function() { that.updateChart(callback); });
                    return false;
                }
                else {
                    error('chart library "' + this.library_name + '" is not available.');
                    if(typeof callback === 'function') callback();
                    return false;
                }
            }

            this.clearSelection();
            this.chartURL();

            if(this.debug === true)
                this.log('updating from ' + this.data_url);

            NETDATA.statistics.refreshes_total++;
            NETDATA.statistics.refreshes_active++;

            if(NETDATA.statistics.refreshes_active > NETDATA.statistics.refreshes_active_max)
                NETDATA.statistics.refreshes_active_max = NETDATA.statistics.refreshes_active;

            this._updating = true;

            this.xhr = $.ajax( {
                url: this.data_url,
                cache: false,
                async: true,
                xhrFields: { withCredentials: true } // required for the cookie
            })
            .done(function(data) {
                that.xhr = undefined;

                if(that.debug === true)
                    that.log('data received. updating chart.');

                that.updateChartWithData(data);
            })
            .fail(function(msg) {
                that.xhr = undefined;

                if(msg.statusText !== 'abort')
                    error('data download failed for url: ' + that.data_url);
            })
            .always(function() {
                that.xhr = undefined;

                NETDATA.statistics.refreshes_active--;
                that._updating = false;
                if(typeof callback === 'function') callback();
            });

            return true;
        };

        this.isVisible = function(nocache) {
            if(typeof nocache === 'undefined')
                nocache = false;

            // this.log('last_visible_check: ' + this.tm.last_visible_check + ', last_page_scroll: ' + NETDATA.options.last_page_scroll);

            // caching - we do not evaluate the charts visibility
            // if the page has not been scrolled since the last check
            if(nocache === false && this.tm.last_visible_check > NETDATA.options.last_page_scroll)
                return this.___isVisible___;

            this.tm.last_visible_check = new Date().getTime();

            var wh = window.innerHeight;
            var x = this.element.getBoundingClientRect();
            var ret = 0;
            var tolerance = 0;

            if(x.width === 0 || x.height === 0) {
                hideChart();
                this.___isVisible___ = false;
                return this.___isVisible___;
            }

            if(x.top < 0 && -x.top > x.height) {
                // the chart is entirely above
                ret = -x.top - x.height;
            }
            else if(x.top > wh) {
                // the chart is entirely below
                ret = x.top - wh;
            }

            if(ret > tolerance) {
                // the chart is too far

                hideChart();
                this.___isVisible___ = false;
                return this.___isVisible___;
            }
            else {
                // the chart is inside or very close

                unhideChart();
                this.___isVisible___ = true;
                return this.___isVisible___;
            }
        };

        this.isAutoRefreshable = function() {
            return (this.current.autorefresh);
        };

        this.canBeAutoRefreshed = function() {
            var now = new Date().getTime();

            if(this.running === true) {
                if(this.debug === true)
                    this.log('I am already running');

                return false;
            }

            if(this.enabled === false) {
                if(this.debug === true)
                    this.log('I am not enabled');

                return false;
            }

            if(this.library === null || this.library.enabled === false) {
                error('charting library "' + this.library_name + '" is not available');
                if(this.debug === true)
                    this.log('My chart library ' + this.library_name + ' is not available');

                return false;
            }

            if(this.isVisible() === false) {
                if(NETDATA.options.debug.visibility === true || this.debug === true)
                    this.log('I am not visible');

                return false;
            }

            if(this.current.force_update_at !== 0 && this.current.force_update_at < now) {
                if(this.debug === true)
                    this.log('timed force update detected - allowing this update');

                this.current.force_update_at = 0;
                return true;
            }

            if(this.isAutoRefreshable() === true) {
                // allow the first update, even if the page is not visible
                if(this.updates_counter && this.updates_since_last_unhide && NETDATA.options.page_is_visible === false) {
                    if(NETDATA.options.debug.focus === true || this.debug === true)
                        this.log('canBeAutoRefreshed(): page does not have focus');

                    return false;
                }

                if(this.needsRecreation() === true) {
                    if(this.debug === true)
                        this.log('canBeAutoRefreshed(): needs re-creation.');

                    return true;
                }

                // options valid only for autoRefresh()
                if(NETDATA.options.auto_refresher_stop_until === 0 || NETDATA.options.auto_refresher_stop_until < now) {
                    if(NETDATA.globalPanAndZoom.isActive()) {
                        if(NETDATA.globalPanAndZoom.shouldBeAutoRefreshed(this)) {
                            if(this.debug === true)
                                this.log('canBeAutoRefreshed(): global panning: I need an update.');

                            return true;
                        }
                        else {
                            if(this.debug === true)
                                this.log('canBeAutoRefreshed(): global panning: I am already up to date.');

                            return false;
                        }
                    }

                    if(this.selected === true) {
                        if(this.debug === true)
                            this.log('canBeAutoRefreshed(): I have a selection in place.');

                        return false;
                    }

                    if(this.paused === true) {
                        if(this.debug === true)
                            this.log('canBeAutoRefreshed(): I am paused.');

                        return false;
                    }

                    if(now - this.tm.last_autorefreshed >= this.data_update_every) {
                        if(this.debug === true)
                            this.log('canBeAutoRefreshed(): It is time to update me.');

                        return true;
                    }
                }
            }

            return false;
        };

        this.autoRefresh = function(callback) {
            if(this.canBeAutoRefreshed() === true && this.running === false) {
                var state = this;

                state.running = true;
                state.updateChart(function() {
                    state.running = false;

                    if(typeof callback !== 'undefined')
                        callback();
                });
            }
            else {
                if(typeof callback !== 'undefined')
                    callback();
            }
        };

        this._defaultsFromDownloadedChart = function(chart) {
            this.chart = chart;
            this.chart_url = chart.url;
            this.data_update_every = chart.update_every * 1000;
            this.data_points = Math.round(this.chartWidth() / this.chartPixelsPerPoint());
            this.tm.last_info_downloaded = new Date().getTime();

            if(this.title === null)
                this.title = chart.title;

            if(this.units === null)
                this.units = chart.units;
        };

        // fetch the chart description from the netdata server
        this.getChart = function(callback) {
            this.chart = NETDATA.chartRegistry.get(this.host, this.id);
            if(this.chart) {
                this._defaultsFromDownloadedChart(this.chart);
                if(typeof callback === 'function') callback();
            }
            else {
                this.chart_url = "/api/v1/chart?chart=" + this.id;

                if(this.debug === true)
                    this.log('downloading ' + this.chart_url);

                $.ajax( {
                    url:  this.host + this.chart_url,
                    cache: false,
                    async: true,
                    xhrFields: { withCredentials: true } // required for the cookie
                })
                .done(function(chart) {
                    chart.url = that.chart_url;
                    that._defaultsFromDownloadedChart(chart);
                    NETDATA.chartRegistry.add(that.host, that.id, chart);
                })
                .fail(function() {
                    NETDATA.error(404, that.chart_url);
                    error('chart not found on url "' + that.chart_url + '"');
                })
                .always(function() {
                    if(typeof callback === 'function') callback();
                });
            }
        };

        // ============================================================================================================
        // INITIALIZATION

        init();
    };

    NETDATA.resetAllCharts = function(state) {
        // first clear the global selection sync
        // to make sure no chart is in selected state
        state.globalSelectionSyncStop();

        // there are 2 possibilities here
        // a. state is the global Pan and Zoom master
        // b. state is not the global Pan and Zoom master
        var master = true;
        if(NETDATA.globalPanAndZoom.isMaster(state) === false)
            master = false;

        // clear the global Pan and Zoom
        // this will also refresh the master
        // and unblock any charts currently mirroring the master
        NETDATA.globalPanAndZoom.clearMaster();

        // if we were not the master, reset our status too
        // this is required because most probably the mouse
        // is over this chart, blocking it from auto-refreshing
        if(master === false && (state.paused === true || state.selected === true))
            state.resetChart();
    };

    // get or create a chart state, given a DOM element
    NETDATA.chartState = function(element) {
        var state = $(element).data('netdata-state-object') || null;
        if(state === null) {
            state = new chartState(element);
            $(element).data('netdata-state-object', state);
        }
        return state;
    };

    // ----------------------------------------------------------------------------------------------------------------
    // Library functions

    // Load a script without jquery
    // This is used to load jquery - after it is loaded, we use jquery
    NETDATA._loadjQuery = function(callback) {
        if(typeof jQuery === 'undefined') {
            if(NETDATA.options.debug.main_loop === true)
                console.log('loading ' + NETDATA.jQuery);

            var script = document.createElement('script');
            script.type = 'text/javascript';
            script.async = true;
            script.src = NETDATA.jQuery;

            // script.onabort = onError;
            script.onerror = function(err, t) { NETDATA.error(101, NETDATA.jQuery); };
            if(typeof callback === "function")
                script.onload = callback;

            var s = document.getElementsByTagName('script')[0];
            s.parentNode.insertBefore(script, s);
        }
        else if(typeof callback === "function")
            callback();
    };

    NETDATA._loadCSS = function(filename) {
        // don't use jQuery here
        // styles are loaded before jQuery
        // to eliminate showing an unstyled page to the user

        var fileref = document.createElement("link");
        fileref.setAttribute("rel", "stylesheet");
        fileref.setAttribute("type", "text/css");
        fileref.setAttribute("href", filename);

        if (typeof fileref !== 'undefined')
            document.getElementsByTagName("head")[0].appendChild(fileref);
    };

    NETDATA.colorHex2Rgb = function(hex) {
        // Expand shorthand form (e.g. "03F") to full form (e.g. "0033FF")
        var shorthandRegex = /^#?([a-f\d])([a-f\d])([a-f\d])$/i;
            hex = hex.replace(shorthandRegex, function(m, r, g, b) {
            return r + r + g + g + b + b;
        });

        var result = /^#?([a-f\d]{2})([a-f\d]{2})([a-f\d]{2})$/i.exec(hex);
        return result ? {
            r: parseInt(result[1], 16),
            g: parseInt(result[2], 16),
            b: parseInt(result[3], 16)
        } : null;
    };

    NETDATA.colorLuminance = function(hex, lum) {
        // validate hex string
        hex = String(hex).replace(/[^0-9a-f]/gi, '');
        if (hex.length < 6)
            hex = hex[0]+hex[0]+hex[1]+hex[1]+hex[2]+hex[2];

        lum = lum || 0;

        // convert to decimal and change luminosity
        var rgb = "#", c, i;
        for (i = 0; i < 3; i++) {
            c = parseInt(hex.substr(i*2,2), 16);
            c = Math.round(Math.min(Math.max(0, c + (c * lum)), 255)).toString(16);
            rgb += ("00"+c).substr(c.length);
        }

        return rgb;
    };

    NETDATA.guid = function() {
        function s4() {
            return Math.floor((1 + Math.random()) * 0x10000)
                    .toString(16)
                    .substring(1);
            }

            return s4() + s4() + '-' + s4() + '-' + s4() + '-' + s4() + '-' + s4() + s4() + s4();
    };

    NETDATA.zeropad = function(x) {
        if(x > -10 && x < 10) return '0' + x.toString();
        else return x.toString();
    };

    // user function to signal us the DOM has been
    // updated.
    NETDATA.updatedDom = function() {
        NETDATA.options.updated_dom = true;
    };

    NETDATA.ready = function(callback) {
        NETDATA.options.pauseCallback = callback;
    };

    NETDATA.pause = function(callback) {
        if(NETDATA.options.pause === true)
            callback();
        else
            NETDATA.options.pauseCallback = callback;
    };

    NETDATA.unpause = function() {
        NETDATA.options.pauseCallback = null;
        NETDATA.options.updated_dom = true;
        NETDATA.options.pause = false;
    };

    // ----------------------------------------------------------------------------------------------------------------

    // this is purely sequencial charts refresher
    // it is meant to be autonomous
    NETDATA.chartRefresherNoParallel = function(index) {
        if(NETDATA.options.debug.mail_loop === true)
            console.log('NETDATA.chartRefresherNoParallel(' + index + ')');

        if(NETDATA.options.updated_dom === true) {
            // the dom has been updated
            // get the dom parts again
            NETDATA.parseDom(NETDATA.chartRefresher);
            return;
        }
        if(index >= NETDATA.options.targets.length) {
            if(NETDATA.options.debug.main_loop === true)
                console.log('waiting to restart main loop...');

            NETDATA.options.auto_refresher_fast_weight = 0;

            setTimeout(function() {
                NETDATA.chartRefresher();
            }, NETDATA.options.current.idle_between_loops);
        }
        else {
            var state = NETDATA.options.targets[index];

            if(NETDATA.options.auto_refresher_fast_weight < NETDATA.options.current.fast_render_timeframe) {
                if(NETDATA.options.debug.main_loop === true)
                    console.log('fast rendering...');

                state.autoRefresh(function() {
                    NETDATA.chartRefresherNoParallel(++index);
                });
            }
            else {
                if(NETDATA.options.debug.main_loop === true) console.log('waiting for next refresh...');
                NETDATA.options.auto_refresher_fast_weight = 0;

                setTimeout(function() {
                    state.autoRefresh(function() {
                        NETDATA.chartRefresherNoParallel(++index);
                    });
                }, NETDATA.options.current.idle_between_charts);
            }
        }
    };

    // this is part of the parallel refresher
    // its cause is to refresh sequencially all the charts
    // that depend on chart library initialization
    // it will call the parallel refresher back
    // as soon as it sees a chart that its chart library
    // is initialized
    NETDATA.chartRefresher_uninitialized = function() {
        if(NETDATA.options.updated_dom === true) {
            // the dom has been updated
            // get the dom parts again
            NETDATA.parseDom(NETDATA.chartRefresher);
            return;
        }

        if(NETDATA.options.sequencial.length === 0)
            NETDATA.chartRefresher();
        else {
            var state = NETDATA.options.sequencial.pop();
            if(state.library.initialized === true)
                NETDATA.chartRefresher();
            else
                state.autoRefresh(NETDATA.chartRefresher_uninitialized);
        }
    };

    NETDATA.chartRefresherWaitTime = function() {
        return NETDATA.options.current.idle_parallel_loops;
    };

    // the default refresher
    // it will create 2 sets of charts:
    // - the ones that can be refreshed in parallel
    // - the ones that depend on something else
    // the first set will be executed in parallel
    // the second will be given to NETDATA.chartRefresher_uninitialized()
    NETDATA.chartRefresher = function() {
        // console.log('auto-refresher...');

        if(NETDATA.options.pause === true) {
            // console.log('auto-refresher is paused');
            setTimeout(NETDATA.chartRefresher,
                NETDATA.chartRefresherWaitTime());
            return;
        }

        if(typeof NETDATA.options.pauseCallback === 'function') {
            // console.log('auto-refresher is calling pauseCallback');
            NETDATA.options.pause = true;
            NETDATA.options.pauseCallback();
            NETDATA.chartRefresher();
            return;
        }

        if(NETDATA.options.current.parallel_refresher === false) {
            // console.log('auto-refresher is calling chartRefresherNoParallel(0)');
            NETDATA.chartRefresherNoParallel(0);
            return;
        }

        if(NETDATA.options.updated_dom === true) {
            // the dom has been updated
            // get the dom parts again
            // console.log('auto-refresher is calling parseDom()');
            NETDATA.parseDom(NETDATA.chartRefresher);
            return;
        }

        var parallel = new Array();
        var targets = NETDATA.options.targets;
        var len = targets.length;
        var state;
        while(len--) {
            state = targets[len];
            if(state.isVisible() === false || state.running === true)
                continue;

            if(state.library.initialized === false) {
                if(state.library.enabled === true) {
                    state.library.initialize(NETDATA.chartRefresher);
                    return;
                }
                else {
                    state.error('chart library "' + state.library_name + '" is not enabled.');
                }
            }

            parallel.unshift(state);
        }

        if(parallel.length > 0) {
            // console.log('auto-refresher executing in parallel for ' + parallel.length.toString() + ' charts');
            // this will execute the jobs in parallel
            $(parallel).each(function() {
                this.autoRefresh();
            })
        }
        //else {
        //    console.log('auto-refresher nothing to do');
        //}

        // run the next refresh iteration
        setTimeout(NETDATA.chartRefresher,
            NETDATA.chartRefresherWaitTime());
    };

    NETDATA.parseDom = function(callback) {
        NETDATA.options.last_page_scroll = new Date().getTime();
        NETDATA.options.updated_dom = false;

        var targets = $('div[data-netdata]'); //.filter(':visible');

        if(NETDATA.options.debug.main_loop === true)
            console.log('DOM updated - there are ' + targets.length + ' charts on page.');

        NETDATA.options.targets = new Array();
        var len = targets.length;
        while(len--) {
            // the initialization will take care of sizing
            // and the "loading..." message
            NETDATA.options.targets.push(NETDATA.chartState(targets[len]));
        }

        if(typeof callback === 'function') callback();
    };

    // this is the main function - where everything starts
    NETDATA.start = function() {
        // this should be called only once

        NETDATA.options.page_is_visible = true;

        $(window).blur(function() {
            if(NETDATA.options.current.stop_updates_when_focus_is_lost === true) {
                NETDATA.options.page_is_visible = false;
                if(NETDATA.options.debug.focus === true)
                    console.log('Lost Focus!');
            }
        });

        $(window).focus(function() {
            if(NETDATA.options.current.stop_updates_when_focus_is_lost === true) {
                NETDATA.options.page_is_visible = true;
                if(NETDATA.options.debug.focus === true)
                    console.log('Focus restored!');
            }
        });

        if(typeof document.hasFocus === 'function' && !document.hasFocus()) {
            if(NETDATA.options.current.stop_updates_when_focus_is_lost === true) {
                NETDATA.options.page_is_visible = false;
                if(NETDATA.options.debug.focus === true)
                    console.log('Document has no focus!');
            }
        }

        // bootstrap tab switching
        $('a[data-toggle="tab"]').on('shown.bs.tab', NETDATA.onscroll);

        // bootstrap modal switching
        $('.modal').on('hidden.bs.modal', NETDATA.onscroll);
        $('.modal').on('shown.bs.modal', NETDATA.onscroll);

        // bootstrap collapse switching
        $('.collapse').on('hidden.bs.collapse', NETDATA.onscroll);
        $('.collapse').on('shown.bs.collapse', NETDATA.onscroll);

        NETDATA.parseDom(NETDATA.chartRefresher);

        // Alarms initialization
        if(netdataShowAlarms === true)
            setTimeout(NETDATA.alarms.init, 1000);

        // Registry initialization
        setTimeout(NETDATA.registry.init, 1500);
    };

    // ----------------------------------------------------------------------------------------------------------------
    // peity

    NETDATA.peityInitialize = function(callback) {
        if(typeof netdataNoPeitys === 'undefined' || !netdataNoPeitys) {
            $.ajax({
                url: NETDATA.peity_js,
                cache: true,
                dataType: "script",
                xhrFields: { withCredentials: true } // required for the cookie
            })
            .done(function() {
                NETDATA.registerChartLibrary('peity', NETDATA.peity_js);
            })
            .fail(function() {
                NETDATA.chartLibraries.peity.enabled = false;
                NETDATA.error(100, NETDATA.peity_js);
            })
            .always(function() {
                if(typeof callback === "function")
                    callback();
            });
        }
        else {
            NETDATA.chartLibraries.peity.enabled = false;
            if(typeof callback === "function")
                callback();
        }
    };

    NETDATA.peityChartUpdate = function(state, data) {
        state.peity_instance.innerHTML = data.result;

        if(state.peity_options.stroke !== state.chartColors()[0]) {
            state.peity_options.stroke = state.chartColors()[0];
            if(state.chart.chart_type === 'line')
                state.peity_options.fill = NETDATA.themes.current.background;
            else
                state.peity_options.fill = NETDATA.colorLuminance(state.chartColors()[0], NETDATA.chartDefaults.fill_luminance);
        }

        $(state.peity_instance).peity('line', state.peity_options);
        return true;
    };

    NETDATA.peityChartCreate = function(state, data) {
        state.peity_instance = document.createElement('div');
        state.element_chart.appendChild(state.peity_instance);

        var self = $(state.element);
        state.peity_options = {
            stroke: NETDATA.themes.current.foreground,
            strokeWidth: self.data('peity-strokewidth') || 1,
            width: state.chartWidth(),
            height: state.chartHeight(),
            fill: NETDATA.themes.current.foreground
        };

        NETDATA.peityChartUpdate(state, data);
        return true;
    };

    // ----------------------------------------------------------------------------------------------------------------
    // sparkline

    NETDATA.sparklineInitialize = function(callback) {
        if(typeof netdataNoSparklines === 'undefined' || !netdataNoSparklines) {
            $.ajax({
                url: NETDATA.sparkline_js,
                cache: true,
                dataType: "script",
                xhrFields: { withCredentials: true } // required for the cookie
            })
            .done(function() {
                NETDATA.registerChartLibrary('sparkline', NETDATA.sparkline_js);
            })
            .fail(function() {
                NETDATA.chartLibraries.sparkline.enabled = false;
                NETDATA.error(100, NETDATA.sparkline_js);
            })
            .always(function() {
                if(typeof callback === "function")
                    callback();
            });
        }
        else {
            NETDATA.chartLibraries.sparkline.enabled = false;
            if(typeof callback === "function")
                callback();
        }
    };

    NETDATA.sparklineChartUpdate = function(state, data) {
        state.sparkline_options.width = state.chartWidth();
        state.sparkline_options.height = state.chartHeight();

        $(state.element_chart).sparkline(data.result, state.sparkline_options);
        return true;
    };

    NETDATA.sparklineChartCreate = function(state, data) {
        var self = $(state.element);
        var type = self.data('sparkline-type') || 'line';
        var lineColor = self.data('sparkline-linecolor') || state.chartColors()[0];
        var fillColor = self.data('sparkline-fillcolor') || (state.chart.chart_type === 'line')?NETDATA.themes.current.background:NETDATA.colorLuminance(lineColor, NETDATA.chartDefaults.fill_luminance);
        var chartRangeMin = self.data('sparkline-chartrangemin') || undefined;
        var chartRangeMax = self.data('sparkline-chartrangemax') || undefined;
        var composite = self.data('sparkline-composite') || undefined;
        var enableTagOptions = self.data('sparkline-enabletagoptions') || undefined;
        var tagOptionPrefix = self.data('sparkline-tagoptionprefix') || undefined;
        var tagValuesAttribute = self.data('sparkline-tagvaluesattribute') || undefined;
        var disableHiddenCheck = self.data('sparkline-disablehiddencheck') || undefined;
        var defaultPixelsPerValue = self.data('sparkline-defaultpixelspervalue') || undefined;
        var spotColor = self.data('sparkline-spotcolor') || undefined;
        var minSpotColor = self.data('sparkline-minspotcolor') || undefined;
        var maxSpotColor = self.data('sparkline-maxspotcolor') || undefined;
        var spotRadius = self.data('sparkline-spotradius') || undefined;
        var valueSpots = self.data('sparkline-valuespots') || undefined;
        var highlightSpotColor = self.data('sparkline-highlightspotcolor') || undefined;
        var highlightLineColor = self.data('sparkline-highlightlinecolor') || undefined;
        var lineWidth = self.data('sparkline-linewidth') || undefined;
        var normalRangeMin = self.data('sparkline-normalrangemin') || undefined;
        var normalRangeMax = self.data('sparkline-normalrangemax') || undefined;
        var drawNormalOnTop = self.data('sparkline-drawnormalontop') || undefined;
        var xvalues = self.data('sparkline-xvalues') || undefined;
        var chartRangeClip = self.data('sparkline-chartrangeclip') || undefined;
        var chartRangeMinX = self.data('sparkline-chartrangeminx') || undefined;
        var chartRangeMaxX = self.data('sparkline-chartrangemaxx') || undefined;
        var disableInteraction = self.data('sparkline-disableinteraction') || false;
        var disableTooltips = self.data('sparkline-disabletooltips') || false;
        var disableHighlight = self.data('sparkline-disablehighlight') || false;
        var highlightLighten = self.data('sparkline-highlightlighten') || 1.4;
        var highlightColor = self.data('sparkline-highlightcolor') || undefined;
        var tooltipContainer = self.data('sparkline-tooltipcontainer') || undefined;
        var tooltipClassname = self.data('sparkline-tooltipclassname') || undefined;
        var tooltipFormat = self.data('sparkline-tooltipformat') || undefined;
        var tooltipPrefix = self.data('sparkline-tooltipprefix') || undefined;
        var tooltipSuffix = self.data('sparkline-tooltipsuffix') || ' ' + state.units;
        var tooltipSkipNull = self.data('sparkline-tooltipskipnull') || true;
        var tooltipValueLookups = self.data('sparkline-tooltipvaluelookups') || undefined;
        var tooltipFormatFieldlist = self.data('sparkline-tooltipformatfieldlist') || undefined;
        var tooltipFormatFieldlistKey = self.data('sparkline-tooltipformatfieldlistkey') || undefined;
        var numberFormatter = self.data('sparkline-numberformatter') || function(n){ return n.toFixed(2); };
        var numberDigitGroupSep = self.data('sparkline-numberdigitgroupsep') || undefined;
        var numberDecimalMark = self.data('sparkline-numberdecimalmark') || undefined;
        var numberDigitGroupCount = self.data('sparkline-numberdigitgroupcount') || undefined;
        var animatedZooms = self.data('sparkline-animatedzooms') || false;

        if(spotColor === 'disable') spotColor='';
        if(minSpotColor === 'disable') minSpotColor='';
        if(maxSpotColor === 'disable') maxSpotColor='';

        state.sparkline_options = {
            type: type,
            lineColor: lineColor,
            fillColor: fillColor,
            chartRangeMin: chartRangeMin,
            chartRangeMax: chartRangeMax,
            composite: composite,
            enableTagOptions: enableTagOptions,
            tagOptionPrefix: tagOptionPrefix,
            tagValuesAttribute: tagValuesAttribute,
            disableHiddenCheck: disableHiddenCheck,
            defaultPixelsPerValue: defaultPixelsPerValue,
            spotColor: spotColor,
            minSpotColor: minSpotColor,
            maxSpotColor: maxSpotColor,
            spotRadius: spotRadius,
            valueSpots: valueSpots,
            highlightSpotColor: highlightSpotColor,
            highlightLineColor: highlightLineColor,
            lineWidth: lineWidth,
            normalRangeMin: normalRangeMin,
            normalRangeMax: normalRangeMax,
            drawNormalOnTop: drawNormalOnTop,
            xvalues: xvalues,
            chartRangeClip: chartRangeClip,
            chartRangeMinX: chartRangeMinX,
            chartRangeMaxX: chartRangeMaxX,
            disableInteraction: disableInteraction,
            disableTooltips: disableTooltips,
            disableHighlight: disableHighlight,
            highlightLighten: highlightLighten,
            highlightColor: highlightColor,
            tooltipContainer: tooltipContainer,
            tooltipClassname: tooltipClassname,
            tooltipChartTitle: state.title,
            tooltipFormat: tooltipFormat,
            tooltipPrefix: tooltipPrefix,
            tooltipSuffix: tooltipSuffix,
            tooltipSkipNull: tooltipSkipNull,
            tooltipValueLookups: tooltipValueLookups,
            tooltipFormatFieldlist: tooltipFormatFieldlist,
            tooltipFormatFieldlistKey: tooltipFormatFieldlistKey,
            numberFormatter: numberFormatter,
            numberDigitGroupSep: numberDigitGroupSep,
            numberDecimalMark: numberDecimalMark,
            numberDigitGroupCount: numberDigitGroupCount,
            animatedZooms: animatedZooms,
            width: state.chartWidth(),
            height: state.chartHeight()
        };

        $(state.element_chart).sparkline(data.result, state.sparkline_options);
        return true;
    };

    // ----------------------------------------------------------------------------------------------------------------
    // dygraph

    NETDATA.dygraph = {
        smooth: false
    };

    NETDATA.dygraphToolboxPanAndZoom = function(state, after, before) {
        if(after < state.netdata_first)
            after = state.netdata_first;

        if(before > state.netdata_last)
            before = state.netdata_last;

        state.setMode('zoom');
        state.globalSelectionSyncStop();
        state.globalSelectionSyncDelay();
        state.dygraph_user_action = true;
        state.dygraph_force_zoom = true;
        state.updateChartPanOrZoom(after, before);
        NETDATA.globalPanAndZoom.setMaster(state, after, before);
    };

    NETDATA.dygraphSetSelection = function(state, t) {
        if(typeof state.dygraph_instance !== 'undefined') {
            var r = state.calculateRowForTime(t);
            if(r !== -1)
                state.dygraph_instance.setSelection(r);
            else {
                state.dygraph_instance.clearSelection();
                state.legendShowUndefined();
            }
        }

        return true;
    };

    NETDATA.dygraphClearSelection = function(state, t) {
        if(typeof state.dygraph_instance !== 'undefined') {
            state.dygraph_instance.clearSelection();
        }
        return true;
    };

    NETDATA.dygraphSmoothInitialize = function(callback) {
        $.ajax({
            url: NETDATA.dygraph_smooth_js,
            cache: true,
            dataType: "script",
            xhrFields: { withCredentials: true } // required for the cookie
        })
        .done(function() {
            NETDATA.dygraph.smooth = true;
            smoothPlotter.smoothing = 0.3;
        })
        .fail(function() {
            NETDATA.dygraph.smooth = false;
        })
        .always(function() {
            if(typeof callback === "function")
                callback();
        });
    };

    NETDATA.dygraphInitialize = function(callback) {
        if(typeof netdataNoDygraphs === 'undefined' || !netdataNoDygraphs) {
            $.ajax({
                url: NETDATA.dygraph_js,
                cache: true,
                dataType: "script",
                xhrFields: { withCredentials: true } // required for the cookie
            })
            .done(function() {
                NETDATA.registerChartLibrary('dygraph', NETDATA.dygraph_js);
            })
            .fail(function() {
                NETDATA.chartLibraries.dygraph.enabled = false;
                NETDATA.error(100, NETDATA.dygraph_js);
            })
            .always(function() {
                if(NETDATA.chartLibraries.dygraph.enabled === true && NETDATA.options.current.smooth_plot === true)
                    NETDATA.dygraphSmoothInitialize(callback);
                else if(typeof callback === "function")
                    callback();
            });
        }
        else {
            NETDATA.chartLibraries.dygraph.enabled = false;
            if(typeof callback === "function")
                callback();
        }
    };

    NETDATA.dygraphChartUpdate = function(state, data) {
        var dygraph = state.dygraph_instance;

        if(typeof dygraph === 'undefined')
            return NETDATA.dygraphChartCreate(state, data);

        // when the chart is not visible, and hidden
        // if there is a window resize, dygraph detects
        // its element size as 0x0.
        // this will make it re-appear properly

        if(state.tm.last_unhidden > state.dygraph_last_rendered)
            dygraph.resize();

        var options = {
                file: data.result.data,
                colors: state.chartColors(),
                labels: data.result.labels,
                labelsDivWidth: state.chartWidth() - 70,
                visibility: state.dimensions_visibility.selected2BooleanArray(state.data.dimension_names)
        };

        if(state.dygraph_force_zoom === true) {
            if(NETDATA.options.debug.dygraph === true || state.debug === true)
                state.log('dygraphChartUpdate() forced zoom update');

            options.dateWindow = (state.requested_padding !== null)?[ state.view_after, state.view_before ]:null;
            options.valueRange = state.dygraph_options.valueRange;
            options.isZoomedIgnoreProgrammaticZoom = true;
            state.dygraph_force_zoom = false;
        }
        else if(state.current.name !== 'auto') {
            if(NETDATA.options.debug.dygraph === true || state.debug === true)
                state.log('dygraphChartUpdate() loose update');

            options.valueRange = state.dygraph_options.valueRange;
        }
        else {
            if(NETDATA.options.debug.dygraph === true || state.debug === true)
                state.log('dygraphChartUpdate() strict update');

            options.dateWindow = (state.requested_padding !== null)?[ state.view_after, state.view_before ]:null;
            options.valueRange = state.dygraph_options.valueRange;
            options.isZoomedIgnoreProgrammaticZoom = true;
        }

        if(state.dygraph_smooth_eligible === true) {
            if((NETDATA.options.current.smooth_plot === true && state.dygraph_options.plotter !== smoothPlotter)
                || (NETDATA.options.current.smooth_plot === false && state.dygraph_options.plotter === smoothPlotter)) {
                NETDATA.dygraphChartCreate(state, data);
                return;
            }
        }

        dygraph.updateOptions(options);

        state.dygraph_last_rendered = new Date().getTime();
        return true;
    };

    NETDATA.dygraphChartCreate = function(state, data) {
        if(NETDATA.options.debug.dygraph === true || state.debug === true)
            state.log('dygraphChartCreate()');

        var self = $(state.element);

        var chart_type = state.chart.chart_type;
        if(chart_type === 'stacked' && data.dimensions === 1) chart_type = 'area';
        chart_type = self.data('dygraph-type') || chart_type;

        var smooth = (chart_type === 'line' && !NETDATA.chartLibraries.dygraph.isSparkline(state))?true:false;
        smooth = self.data('dygraph-smooth') || smooth;

        if(NETDATA.dygraph.smooth === false)
            smooth = false;

        var strokeWidth = (chart_type === 'stacked')?0.1:((smooth)?1.5:0.7)
        var highlightCircleSize = (NETDATA.chartLibraries.dygraph.isSparkline(state))?3:4;

        state.dygraph_options = {
            colors: self.data('dygraph-colors') || state.chartColors(),

            // leave a few pixels empty on the right of the chart
            rightGap: self.data('dygraph-rightgap') || 5,
            showRangeSelector: self.data('dygraph-showrangeselector') || false,
            showRoller: self.data('dygraph-showroller') || false,

            title: self.data('dygraph-title') || state.title,
            titleHeight: self.data('dygraph-titleheight') || 19,

            legend: self.data('dygraph-legend') || 'always', // 'onmouseover',
            labels: data.result.labels,
            labelsDiv: self.data('dygraph-labelsdiv') || state.element_legend_childs.hidden,
            labelsDivStyles: self.data('dygraph-labelsdivstyles') || { 'fontSize':'1px' },
            labelsDivWidth: self.data('dygraph-labelsdivwidth') || state.chartWidth() - 70,
            labelsSeparateLines: self.data('dygraph-labelsseparatelines') || true,
            labelsShowZeroValues: self.data('dygraph-labelsshowzerovalues') || true,
            labelsKMB: false,
            labelsKMG2: false,
            showLabelsOnHighlight: self.data('dygraph-showlabelsonhighlight') || true,
            hideOverlayOnMouseOut: self.data('dygraph-hideoverlayonmouseout') || true,

            includeZero: self.data('dygraph-includezero') || false,
            xRangePad: self.data('dygraph-xrangepad') || 0,
            yRangePad: self.data('dygraph-yrangepad') || 1,

            valueRange: self.data('dygraph-valuerange') || null,

            ylabel: state.units,
            yLabelWidth: self.data('dygraph-ylabelwidth') || 12,

            // the function to plot the chart
            plotter: null,

            // The width of the lines connecting data points. This can be used to increase the contrast or some graphs.
            strokeWidth: self.data('dygraph-strokewidth') || strokeWidth,
            strokePattern: self.data('dygraph-strokepattern') || undefined,

            // The size of the dot to draw on each point in pixels (see drawPoints). A dot is always drawn when a point is "isolated",
            // i.e. there is a missing point on either side of it. This also controls the size of those dots.
            drawPoints: self.data('dygraph-drawpoints') || false,

            // Draw points at the edges of gaps in the data. This improves visibility of small data segments or other data irregularities.
            drawGapEdgePoints: self.data('dygraph-drawgapedgepoints') || true,

            connectSeparatedPoints: self.data('dygraph-connectseparatedpoints') || false,
            pointSize: self.data('dygraph-pointsize') || 1,

            // enabling this makes the chart with little square lines
            stepPlot: self.data('dygraph-stepplot') || false,

            // Draw a border around graph lines to make crossing lines more easily distinguishable. Useful for graphs with many lines.
            strokeBorderColor: self.data('dygraph-strokebordercolor') || NETDATA.themes.current.background,
            strokeBorderWidth: self.data('dygraph-strokeborderwidth') || (chart_type === 'stacked')?0.0:0.0,

            fillGraph: self.data('dygraph-fillgraph') || (chart_type === 'area' || chart_type === 'stacked')?true:false,
            fillAlpha: self.data('dygraph-fillalpha') || (chart_type === 'stacked')?NETDATA.options.current.color_fill_opacity_stacked:NETDATA.options.current.color_fill_opacity_area,
            stackedGraph: self.data('dygraph-stackedgraph') || (chart_type === 'stacked')?true:false,
            stackedGraphNaNFill: self.data('dygraph-stackedgraphnanfill') || 'none',

            drawAxis: self.data('dygraph-drawaxis') || true,
            axisLabelFontSize: self.data('dygraph-axislabelfontsize') || 10,
            axisLineColor: self.data('dygraph-axislinecolor') || NETDATA.themes.current.axis,
            axisLineWidth: self.data('dygraph-axislinewidth') || 0.3,

            drawGrid: self.data('dygraph-drawgrid') || true,
            drawXGrid: self.data('dygraph-drawxgrid') || undefined,
            drawYGrid: self.data('dygraph-drawygrid') || undefined,
            gridLinePattern: self.data('dygraph-gridlinepattern') || null,
            gridLineWidth: self.data('dygraph-gridlinewidth') || 0.3,
            gridLineColor: self.data('dygraph-gridlinecolor') || NETDATA.themes.current.grid,

            maxNumberWidth: self.data('dygraph-maxnumberwidth') || 8,
            sigFigs: self.data('dygraph-sigfigs') || null,
            digitsAfterDecimal: self.data('dygraph-digitsafterdecimal') || 2,
            valueFormatter: self.data('dygraph-valueformatter') || function(x){ return x.toFixed(2); },

            highlightCircleSize: self.data('dygraph-highlightcirclesize') || highlightCircleSize,
            highlightSeriesOpts: self.data('dygraph-highlightseriesopts') || null, // TOO SLOW: { strokeWidth: 1.5 },
            highlightSeriesBackgroundAlpha: self.data('dygraph-highlightseriesbackgroundalpha') || null, // TOO SLOW: (chart_type === 'stacked')?0.7:0.5,

            pointClickCallback: self.data('dygraph-pointclickcallback') || undefined,
            visibility: state.dimensions_visibility.selected2BooleanArray(state.data.dimension_names),
            axes: {
                x: {
                    pixelsPerLabel: 50,
                    ticker: Dygraph.dateTicker,
                    axisLabelFormatter: function (d, gran) {
                        return NETDATA.zeropad(d.getHours()) + ":" + NETDATA.zeropad(d.getMinutes()) + ":" + NETDATA.zeropad(d.getSeconds());
                    },
                    valueFormatter: function (ms) {
                        var d = new Date(ms);
                        return d.toLocaleDateString() + ' ' + d.toLocaleTimeString();
                        // return NETDATA.zeropad(d.getHours()) + ":" + NETDATA.zeropad(d.getMinutes()) + ":" + NETDATA.zeropad(d.getSeconds());
                    }
                },
                y: {
                    pixelsPerLabel: 15,
                    valueFormatter: function (x) {
                        // we format legends with the state object
                        // no need to do anything here
                        // return (Math.round(x*100) / 100).toLocaleString();
                        // return state.legendFormatValue(x);
                        return x;
                    }
                }
            },
            legendFormatter: function(data) {
                var elements = state.element_legend_childs;

                // if the hidden div is not there
                // we are not managing the legend
                if(elements.hidden === null) return;

                if (typeof data.x !== 'undefined') {
                    state.legendSetDate(data.x);
                    var i = data.series.length;
                    while(i--) {
                        var series = data.series[i];
                        if(!series.isVisible) continue;
                        state.legendSetLabelValue(series.label, series.y);
                    }
                }

                return '';
            },
            drawCallback: function(dygraph, is_initial) {
                if(state.current.name !== 'auto' && state.dygraph_user_action === true) {
                    state.dygraph_user_action = false;

                    var x_range = dygraph.xAxisRange();
                    var after = Math.round(x_range[0]);
                    var before = Math.round(x_range[1]);

                    if(NETDATA.options.debug.dygraph === true)
                        state.log('dygraphDrawCallback(dygraph, ' + is_initial + '): ' + (after / 1000).toString() + ' - ' + (before / 1000).toString());

                    if(before <= state.netdata_last && after >= state.netdata_first)
                        state.updateChartPanOrZoom(after, before);
                }
            },
            zoomCallback: function(minDate, maxDate, yRanges) {
                if(NETDATA.options.debug.dygraph === true)
                    state.log('dygraphZoomCallback()');

                state.globalSelectionSyncStop();
                state.globalSelectionSyncDelay();
                state.setMode('zoom');

                // refresh it to the greatest possible zoom level
                state.dygraph_user_action = true;
                state.dygraph_force_zoom = true;
                state.updateChartPanOrZoom(minDate, maxDate);
            },
            highlightCallback: function(event, x, points, row, seriesName) {
                if(NETDATA.options.debug.dygraph === true || state.debug === true)
                    state.log('dygraphHighlightCallback()');

                state.pauseChart();

                // there is a bug in dygraph when the chart is zoomed enough
                // the time it thinks is selected is wrong
                // here we calculate the time t based on the row number selected
                // which is ok
                var t = state.data_after + row * state.data_update_every;
                // console.log('row = ' + row + ', x = ' + x + ', t = ' + t + ' ' + ((t === x)?'SAME':(Math.abs(x-t)<=state.data_update_every)?'SIMILAR':'DIFFERENT') + ', rows in db: ' + state.data_points + ' visible(x) = ' + state.timeIsVisible(x) + ' visible(t) = ' + state.timeIsVisible(t) + ' r(x) = ' + state.calculateRowForTime(x) + ' r(t) = ' + state.calculateRowForTime(t) + ' range: ' + state.data_after + ' - ' + state.data_before + ' real: ' + state.data.after + ' - ' + state.data.before + ' every: ' + state.data_update_every);

                state.globalSelectionSync(x);

                // fix legend zIndex using the internal structures of dygraph legend module
                // this works, but it is a hack!
                // state.dygraph_instance.plugins_[0].plugin.legend_div_.style.zIndex = 10000;
            },
            unhighlightCallback: function(event) {
                if(NETDATA.options.debug.dygraph === true || state.debug === true)
                    state.log('dygraphUnhighlightCallback()');

                state.unpauseChart();
                state.globalSelectionSyncStop();
            },
            interactionModel : {
                mousedown: function(event, dygraph, context) {
                    if(NETDATA.options.debug.dygraph === true || state.debug === true)
                        state.log('interactionModel.mousedown()');

                    state.dygraph_user_action = true;
                    state.globalSelectionSyncStop();

                    if(NETDATA.options.debug.dygraph === true)
                        state.log('dygraphMouseDown()');

                    // Right-click should not initiate a zoom.
                    if(event.button && event.button === 2) return;

                    context.initializeMouseDown(event, dygraph, context);

                    if(event.button && event.button === 1) {
                        if (event.altKey || event.shiftKey) {
                            state.setMode('pan');
                            state.globalSelectionSyncDelay();
                            Dygraph.startPan(event, dygraph, context);
                        }
                        else {
                            state.setMode('zoom');
                            state.globalSelectionSyncDelay();
                            Dygraph.startZoom(event, dygraph, context);
                        }
                    }
                    else {
                        if (event.altKey || event.shiftKey) {
                            state.setMode('zoom');
                            state.globalSelectionSyncDelay();
                            Dygraph.startZoom(event, dygraph, context);
                        }
                        else {
                            state.setMode('pan');
                            state.globalSelectionSyncDelay();
                            Dygraph.startPan(event, dygraph, context);
                        }
                    }
                },
                mousemove: function(event, dygraph, context) {
                    if(NETDATA.options.debug.dygraph === true || state.debug === true)
                        state.log('interactionModel.mousemove()');

                    if(context.isPanning) {
                        state.dygraph_user_action = true;
                        state.globalSelectionSyncStop();
                        state.globalSelectionSyncDelay();
                        state.setMode('pan');
                        Dygraph.movePan(event, dygraph, context);
                    }
                    else if(context.isZooming) {
                        state.dygraph_user_action = true;
                        state.globalSelectionSyncStop();
                        state.globalSelectionSyncDelay();
                        state.setMode('zoom');
                        Dygraph.moveZoom(event, dygraph, context);
                    }
                },
                mouseup: function(event, dygraph, context) {
                    if(NETDATA.options.debug.dygraph === true || state.debug === true)
                        state.log('interactionModel.mouseup()');

                    if (context.isPanning) {
                        state.dygraph_user_action = true;
                        state.globalSelectionSyncDelay();
                        Dygraph.endPan(event, dygraph, context);
                    }
                    else if (context.isZooming) {
                        state.dygraph_user_action = true;
                        state.globalSelectionSyncDelay();
                        Dygraph.endZoom(event, dygraph, context);
                    }
                },
                click: function(event, dygraph, context) {
                    if(NETDATA.options.debug.dygraph === true || state.debug === true)
                        state.log('interactionModel.click()');

                    event.preventDefault();
                },
                dblclick: function(event, dygraph, context) {
                    if(NETDATA.options.debug.dygraph === true || state.debug === true)
                        state.log('interactionModel.dblclick()');
                    NETDATA.resetAllCharts(state);
                },
                mousewheel: function(event, dygraph, context) {
                    if(NETDATA.options.debug.dygraph === true || state.debug === true)
                        state.log('interactionModel.mousewheel()');

                    // Take the offset of a mouse event on the dygraph canvas and
                    // convert it to a pair of percentages from the bottom left.
                    // (Not top left, bottom is where the lower value is.)
                    function offsetToPercentage(g, offsetX, offsetY) {
                        // This is calculating the pixel offset of the leftmost date.
                        var xOffset = g.toDomCoords(g.xAxisRange()[0], null)[0];
                        var yar0 = g.yAxisRange(0);

                        // This is calculating the pixel of the higest value. (Top pixel)
                        var yOffset = g.toDomCoords(null, yar0[1])[1];

                        // x y w and h are relative to the corner of the drawing area,
                        // so that the upper corner of the drawing area is (0, 0).
                        var x = offsetX - xOffset;
                        var y = offsetY - yOffset;

                        // This is computing the rightmost pixel, effectively defining the
                        // width.
                        var w = g.toDomCoords(g.xAxisRange()[1], null)[0] - xOffset;

                        // This is computing the lowest pixel, effectively defining the height.
                        var h = g.toDomCoords(null, yar0[0])[1] - yOffset;

                        // Percentage from the left.
                        var xPct = w === 0 ? 0 : (x / w);
                        // Percentage from the top.
                        var yPct = h === 0 ? 0 : (y / h);

                        // The (1-) part below changes it from "% distance down from the top"
                        // to "% distance up from the bottom".
                        return [xPct, (1-yPct)];
                    }

                    // Adjusts [x, y] toward each other by zoomInPercentage%
                    // Split it so the left/bottom axis gets xBias/yBias of that change and
                    // tight/top gets (1-xBias)/(1-yBias) of that change.
                    //
                    // If a bias is missing it splits it down the middle.
                    function zoomRange(g, zoomInPercentage, xBias, yBias) {
                        xBias = xBias || 0.5;
                        yBias = yBias || 0.5;

                        function adjustAxis(axis, zoomInPercentage, bias) {
                            var delta = axis[1] - axis[0];
                            var increment = delta * zoomInPercentage;
                            var foo = [increment * bias, increment * (1-bias)];

                            return [ axis[0] + foo[0], axis[1] - foo[1] ];
                        }

                        var yAxes = g.yAxisRanges();
                        var newYAxes = [];
                        for (var i = 0; i < yAxes.length; i++) {
                            newYAxes[i] = adjustAxis(yAxes[i], zoomInPercentage, yBias);
                        }

                        return adjustAxis(g.xAxisRange(), zoomInPercentage, xBias);
                    }

                    if(event.altKey || event.shiftKey) {
                        state.dygraph_user_action = true;

                        state.globalSelectionSyncStop();
                        state.globalSelectionSyncDelay();

                        // http://dygraphs.com/gallery/interaction-api.js
                        var normal = (event.detail) ? event.detail * -1 : event.wheelDelta / 40;
                        var percentage = normal / 50;

                        if (!(event.offsetX && event.offsetY)){
                            event.offsetX = event.layerX - event.target.offsetLeft;
                            event.offsetY = event.layerY - event.target.offsetTop;
                        }

                        var percentages = offsetToPercentage(dygraph, event.offsetX, event.offsetY);
                        var xPct = percentages[0];
                        var yPct = percentages[1];

                        var new_x_range = zoomRange(dygraph, percentage, xPct, yPct);

                        var after = new_x_range[0];
                        var before = new_x_range[1];

                        var first = state.netdata_first + state.data_update_every;
                        var last = state.netdata_last + state.data_update_every;

                        if(before > last) {
                            after -= (before - last);
                            before = last;
                        }
                        if(after < first) {
                            after = first;
                        }

                        state.setMode('zoom');
                        if(state.updateChartPanOrZoom(after, before) === true)
                            dygraph.updateOptions({ dateWindow: [ after, before ] });

                        event.preventDefault();
                    }
                },
                touchstart: function(event, dygraph, context) {
                    if(NETDATA.options.debug.dygraph === true || state.debug === true)
                        state.log('interactionModel.touchstart()');

                    state.dygraph_user_action = true;
                    state.setMode('zoom');
                    state.pauseChart();

                    Dygraph.defaultInteractionModel.touchstart(event, dygraph, context);

                    // we overwrite the touch directions at the end, to overwrite
                    // the internal default of dygraphs
                    context.touchDirections = { x: true, y: false };

                    state.dygraph_last_touch_start = new Date().getTime();
                    state.dygraph_last_touch_move = 0;

                    if(typeof event.touches[0].pageX === 'number')
                        state.dygraph_last_touch_page_x = event.touches[0].pageX;
                    else
                        state.dygraph_last_touch_page_x = 0;
                },
                touchmove: function(event, dygraph, context) {
                    if(NETDATA.options.debug.dygraph === true || state.debug === true)
                        state.log('interactionModel.touchmove()');

                    state.dygraph_user_action = true;
                    Dygraph.defaultInteractionModel.touchmove(event, dygraph, context);

                    state.dygraph_last_touch_move = new Date().getTime();
                },
                touchend: function(event, dygraph, context) {
                    if(NETDATA.options.debug.dygraph === true || state.debug === true)
                        state.log('interactionModel.touchend()');

                    state.dygraph_user_action = true;
                    Dygraph.defaultInteractionModel.touchend(event, dygraph, context);

                    // if it didn't move, it is a selection
                    if(state.dygraph_last_touch_move === 0 && state.dygraph_last_touch_page_x !== 0) {
                        // internal api of dygraphs
                        var pct = (state.dygraph_last_touch_page_x - (dygraph.plotter_.area.x + state.element.getBoundingClientRect().left)) / dygraph.plotter_.area.w;
                        var t = Math.round(state.data_after + (state.data_before - state.data_after) * pct);
                        if(NETDATA.dygraphSetSelection(state, t) === true)
                            state.globalSelectionSync(t);
                    }

                    // if it was double tap within double click time, reset the charts
                    var now = new Date().getTime();
                    if(typeof state.dygraph_last_touch_end !== 'undefined') {
                        if(state.dygraph_last_touch_move === 0) {
                            var dt = now - state.dygraph_last_touch_end;
                            if(dt <= NETDATA.options.current.double_click_speed)
                                NETDATA.resetAllCharts(state);
                        }
                    }

                    // remember the timestamp of the last touch end
                    state.dygraph_last_touch_end = now;
                }
            }
        };

        if(NETDATA.chartLibraries.dygraph.isSparkline(state)) {
            state.dygraph_options.drawGrid = false;
            state.dygraph_options.drawAxis = false;
            state.dygraph_options.title = undefined;
            state.dygraph_options.units = undefined;
            state.dygraph_options.ylabel = undefined;
            state.dygraph_options.yLabelWidth = 0;
            state.dygraph_options.labelsDivWidth = 120;
            state.dygraph_options.labelsDivStyles.width = '120px';
            state.dygraph_options.labelsSeparateLines = true;
            state.dygraph_options.rightGap = 0;
            state.dygraph_options.yRangePad = 1;
        }

        if(smooth === true) {
            state.dygraph_smooth_eligible = true;

            if(NETDATA.options.current.smooth_plot === true)
                state.dygraph_options.plotter = smoothPlotter;
        }
        else state.dygraph_smooth_eligible = false;

        state.dygraph_instance = new Dygraph(state.element_chart,
            data.result.data, state.dygraph_options);

        state.dygraph_force_zoom = false;
        state.dygraph_user_action = false;
        state.dygraph_last_rendered = new Date().getTime();
        return true;
    };

    // ----------------------------------------------------------------------------------------------------------------
    // morris

    NETDATA.morrisInitialize = function(callback) {
        if(typeof netdataNoMorris === 'undefined' || !netdataNoMorris) {

            // morris requires raphael
            if(!NETDATA.chartLibraries.raphael.initialized) {
                if(NETDATA.chartLibraries.raphael.enabled) {
                    NETDATA.raphaelInitialize(function() {
                        NETDATA.morrisInitialize(callback);
                    });
                }
                else {
                    NETDATA.chartLibraries.morris.enabled = false;
                    if(typeof callback === "function")
                        callback();
                }
            }
            else {
                NETDATA._loadCSS(NETDATA.morris_css);

                $.ajax({
                    url: NETDATA.morris_js,
                    cache: true,
                    dataType: "script",
                    xhrFields: { withCredentials: true } // required for the cookie
                })
                .done(function() {
                    NETDATA.registerChartLibrary('morris', NETDATA.morris_js);
                })
                .fail(function() {
                    NETDATA.chartLibraries.morris.enabled = false;
                    NETDATA.error(100, NETDATA.morris_js);
                })
                .always(function() {
                    if(typeof callback === "function")
                        callback();
                });
            }
        }
        else {
            NETDATA.chartLibraries.morris.enabled = false;
            if(typeof callback === "function")
                callback();
        }
    };

    NETDATA.morrisChartUpdate = function(state, data) {
        state.morris_instance.setData(data.result.data);
        return true;
    };

    NETDATA.morrisChartCreate = function(state, data) {

        state.morris_options = {
                element: state.element_chart.id,
                data: data.result.data,
                xkey: 'time',
                ykeys: data.dimension_names,
                labels: data.dimension_names,
                lineWidth: 2,
                pointSize: 3,
                smooth: true,
                hideHover: 'auto',
                parseTime: true,
                continuousLine: false,
                behaveLikeLine: false
        };

        if(state.chart.chart_type === 'line')
            state.morris_instance = new Morris.Line(state.morris_options);

        else if(state.chart.chart_type === 'area') {
            state.morris_options.behaveLikeLine = true;
            state.morris_instance = new Morris.Area(state.morris_options);
        }
        else // stacked
            state.morris_instance = new Morris.Area(state.morris_options);

        return true;
    };

    // ----------------------------------------------------------------------------------------------------------------
    // raphael

    NETDATA.raphaelInitialize = function(callback) {
        if(typeof netdataStopRaphael === 'undefined' || !netdataStopRaphael) {
            $.ajax({
                url: NETDATA.raphael_js,
                cache: true,
                dataType: "script",
                xhrFields: { withCredentials: true } // required for the cookie
            })
            .done(function() {
                NETDATA.registerChartLibrary('raphael', NETDATA.raphael_js);
            })
            .fail(function() {
                NETDATA.chartLibraries.raphael.enabled = false;
                NETDATA.error(100, NETDATA.raphael_js);
            })
            .always(function() {
                if(typeof callback === "function")
                    callback();
            });
        }
        else {
            NETDATA.chartLibraries.raphael.enabled = false;
            if(typeof callback === "function")
                callback();
        }
    };

    NETDATA.raphaelChartUpdate = function(state, data) {
        $(state.element_chart).raphael(data.result, {
            width: state.chartWidth(),
            height: state.chartHeight()
        });

        return false;
    };

    NETDATA.raphaelChartCreate = function(state, data) {
        $(state.element_chart).raphael(data.result, {
            width: state.chartWidth(),
            height: state.chartHeight()
        });

        return false;
    };

    // ----------------------------------------------------------------------------------------------------------------
    // C3

    NETDATA.c3Initialize = function(callback) {
        if(typeof netdataNoC3 === 'undefined' || !netdataNoC3) {

            // C3 requires D3
            if(!NETDATA.chartLibraries.d3.initialized) {
                if(NETDATA.chartLibraries.d3.enabled) {
                    NETDATA.d3Initialize(function() {
                        NETDATA.c3Initialize(callback);
                    });
                }
                else {
                    NETDATA.chartLibraries.c3.enabled = false;
                    if(typeof callback === "function")
                        callback();
                }
            }
            else {
                NETDATA._loadCSS(NETDATA.c3_css);

                $.ajax({
                    url: NETDATA.c3_js,
                    cache: true,
                    dataType: "script",
                    xhrFields: { withCredentials: true } // required for the cookie
                })
                .done(function() {
                    NETDATA.registerChartLibrary('c3', NETDATA.c3_js);
                })
                .fail(function() {
                    NETDATA.chartLibraries.c3.enabled = false;
                    NETDATA.error(100, NETDATA.c3_js);
                })
                .always(function() {
                    if(typeof callback === "function")
                        callback();
                });
            }
        }
        else {
            NETDATA.chartLibraries.c3.enabled = false;
            if(typeof callback === "function")
                callback();
        }
    };

    NETDATA.c3ChartUpdate = function(state, data) {
        state.c3_instance.destroy();
        return NETDATA.c3ChartCreate(state, data);

        //state.c3_instance.load({
        //  rows: data.result,
        //  unload: true
        //});

        //return true;
    };

    NETDATA.c3ChartCreate = function(state, data) {

        state.element_chart.id = 'c3-' + state.uuid;
        // console.log('id = ' + state.element_chart.id);

        state.c3_instance = c3.generate({
            bindto: '#' + state.element_chart.id,
            size: {
                width: state.chartWidth(),
                height: state.chartHeight()
            },
            color: {
                pattern: state.chartColors()
            },
            data: {
                x: 'time',
                rows: data.result,
                type: (state.chart.chart_type === 'line')?'spline':'area-spline'
            },
            axis: {
                x: {
                    type: 'timeseries',
                    tick: {
                        format: function(x) {
                            return NETDATA.zeropad(x.getHours()) + ":" + NETDATA.zeropad(x.getMinutes()) + ":" + NETDATA.zeropad(x.getSeconds());
                        }
                    }
                }
            },
            grid: {
                x: {
                    show: true
                },
                y: {
                    show: true
                }
            },
            point: {
                show: false
            },
            line: {
                connectNull: false
            },
            transition: {
                duration: 0
            },
            interaction: {
                enabled: true
            }
        });

        // console.log(state.c3_instance);

        return true;
    };

    // ----------------------------------------------------------------------------------------------------------------
    // D3

    NETDATA.d3Initialize = function(callback) {
        if(typeof netdataStopD3 === 'undefined' || !netdataStopD3) {
            $.ajax({
                url: NETDATA.d3_js,
                cache: true,
                dataType: "script",
                xhrFields: { withCredentials: true } // required for the cookie
            })
            .done(function() {
                NETDATA.registerChartLibrary('d3', NETDATA.d3_js);
            })
            .fail(function() {
                NETDATA.chartLibraries.d3.enabled = false;
                NETDATA.error(100, NETDATA.d3_js);
            })
            .always(function() {
                if(typeof callback === "function")
                    callback();
            });
        }
        else {
            NETDATA.chartLibraries.d3.enabled = false;
            if(typeof callback === "function")
                callback();
        }
    };

    NETDATA.d3ChartUpdate = function(state, data) {
        return false;
    };

    NETDATA.d3ChartCreate = function(state, data) {
        return false;
    };

    // ----------------------------------------------------------------------------------------------------------------
    // google charts

    NETDATA.googleInitialize = function(callback) {
        if(typeof netdataNoGoogleCharts === 'undefined' || !netdataNoGoogleCharts) {
            $.ajax({
                url: NETDATA.google_js,
                cache: true,
                dataType: "script",
                xhrFields: { withCredentials: true } // required for the cookie
            })
            .done(function() {
                NETDATA.registerChartLibrary('google', NETDATA.google_js);
                google.load('visualization', '1.1', {
                    'packages': ['corechart', 'controls'],
                    'callback': callback
                });
            })
            .fail(function() {
                NETDATA.chartLibraries.google.enabled = false;
                NETDATA.error(100, NETDATA.google_js);
                if(typeof callback === "function")
                    callback();
            });
        }
        else {
            NETDATA.chartLibraries.google.enabled = false;
            if(typeof callback === "function")
                callback();
        }
    };

    NETDATA.googleChartUpdate = function(state, data) {
        var datatable = new google.visualization.DataTable(data.result);
        state.google_instance.draw(datatable, state.google_options);
        return true;
    };

    NETDATA.googleChartCreate = function(state, data) {
        var datatable = new google.visualization.DataTable(data.result);

        state.google_options = {
            colors: state.chartColors(),

            // do not set width, height - the chart resizes itself
            //width: state.chartWidth(),
            //height: state.chartHeight(),
            lineWidth: 1,
            title: state.title,
            fontSize: 11,
            hAxis: {
            //  title: "Time of Day",
            //  format:'HH:mm:ss',
                viewWindowMode: 'maximized',
                slantedText: false,
                format:'HH:mm:ss',
                textStyle: {
                    fontSize: 9
                },
                gridlines: {
                    color: '#EEE'
                }
            },
            vAxis: {
                title: state.units,
                viewWindowMode: 'pretty',
                minValue: -0.1,
                maxValue: 0.1,
                direction: 1,
                textStyle: {
                    fontSize: 9
                },
                gridlines: {
                    color: '#EEE'
                }
            },
            chartArea: {
                width: '65%',
                height: '80%'
            },
            focusTarget: 'category',
            annotation: {
                '1': {
                    style: 'line'
                }
            },
            pointsVisible: 0,
            titlePosition: 'out',
            titleTextStyle: {
                fontSize: 11
            },
            tooltip: {
                isHtml: false,
                ignoreBounds: true,
                textStyle: {
                    fontSize: 9
                }
            },
            curveType: 'function',
            areaOpacity: 0.3,
            isStacked: false
        };

        switch(state.chart.chart_type) {
            case "area":
                state.google_options.vAxis.viewWindowMode = 'maximized';
                state.google_options.areaOpacity = NETDATA.options.current.color_fill_opacity_area;
                state.google_instance = new google.visualization.AreaChart(state.element_chart);
                break;

            case "stacked":
                state.google_options.isStacked = true;
                state.google_options.areaOpacity = NETDATA.options.current.color_fill_opacity_stacked;
                state.google_options.vAxis.viewWindowMode = 'maximized';
                state.google_options.vAxis.minValue = null;
                state.google_options.vAxis.maxValue = null;
                state.google_instance = new google.visualization.AreaChart(state.element_chart);
                break;

            default:
            case "line":
                state.google_options.lineWidth = 2;
                state.google_instance = new google.visualization.LineChart(state.element_chart);
                break;
        }

        state.google_instance.draw(datatable, state.google_options);
        return true;
    };

    // ----------------------------------------------------------------------------------------------------------------

    NETDATA.percentFromValueMax = function(value, max) {
        if(value === null) value = 0;
        if(max < value) max = value;

        var pcent = 0;
        if(max !== 0) {
            pcent = Math.round(value * 100 / max);
            if(pcent === 0 && value > 0) pcent = 1;
        }

        return pcent;
    };

    // ----------------------------------------------------------------------------------------------------------------
    // easy-pie-chart

    NETDATA.easypiechartInitialize = function(callback) {
        if(typeof netdataNoEasyPieChart === 'undefined' || !netdataNoEasyPieChart) {
            $.ajax({
                url: NETDATA.easypiechart_js,
                cache: true,
                dataType: "script",
                xhrFields: { withCredentials: true } // required for the cookie
            })
                .done(function() {
                    NETDATA.registerChartLibrary('easypiechart', NETDATA.easypiechart_js);
                })
                .fail(function() {
                    NETDATA.chartLibraries.easypiechart.enabled = false;
                    NETDATA.error(100, NETDATA.easypiechart_js);
                })
                .always(function() {
                    if(typeof callback === "function")
                        callback();
                })
        }
        else {
            NETDATA.chartLibraries.easypiechart.enabled = false;
            if(typeof callback === "function")
                callback();
        }
    };

    NETDATA.easypiechartClearSelection = function(state) {
        if(typeof state.easyPieChartEvent !== 'undefined') {
            if(state.easyPieChartEvent.timer !== null)
                clearTimeout(state.easyPieChartEvent.timer);

            state.easyPieChartEvent.timer = null;
        }

        if(state.isAutoRefreshable() === true && state.data !== null) {
            NETDATA.easypiechartChartUpdate(state, state.data);
        }
        else {
            state.easyPieChartLabel.innerHTML = state.legendFormatValue(null);
            state.easyPieChart_instance.update(0);
        }
        state.easyPieChart_instance.enableAnimation();

        return true;
    };

    NETDATA.easypiechartSetSelection = function(state, t) {
        if(state.timeIsVisible(t) !== true)
            return NETDATA.easypiechartClearSelection(state);

        var slot = state.calculateRowForTime(t);
        if(slot < 0 || slot >= state.data.result.length)
            return NETDATA.easypiechartClearSelection(state);

        if(typeof state.easyPieChartEvent === 'undefined') {
            state.easyPieChartEvent = {
                timer: null,
                value: 0,
                pcent: 0
            };
        }

        var value = state.data.result[state.data.result.length - 1 - slot];
        var max = (state.easyPieChartMax === null)?state.data.max:state.easyPieChartMax;
        var pcent = NETDATA.percentFromValueMax(value, max);

        state.easyPieChartEvent.value = value;
        state.easyPieChartEvent.pcent = pcent;
        state.easyPieChartLabel.innerHTML = state.legendFormatValue(value);

        if(state.easyPieChartEvent.timer === null) {
            state.easyPieChart_instance.disableAnimation();

            state.easyPieChartEvent.timer = setTimeout(function() {
                state.easyPieChartEvent.timer = null;
                state.easyPieChart_instance.update(state.easyPieChartEvent.pcent);
            }, NETDATA.options.current.charts_selection_animation_delay);
        }

        return true;
    };

    NETDATA.easypiechartChartUpdate = function(state, data) {
        var value, max, pcent;

        if(NETDATA.globalPanAndZoom.isActive() === true || state.isAutoRefreshable() === false) {
            value = null;
            max = 0;
            pcent = 0;
        }
        else {
            value = data.result[0];
            max = (state.easyPieChartMax === null)?data.max:state.easyPieChartMax;
            pcent = NETDATA.percentFromValueMax(value, max);
        }

        state.easyPieChartLabel.innerHTML = state.legendFormatValue(value);
        state.easyPieChart_instance.update(pcent);
        return true;
    };

    NETDATA.easypiechartChartCreate = function(state, data) {
        var self = $(state.element);
        var chart = $(state.element_chart);

        var value = data.result[0];
        var max = self.data('easypiechart-max-value') || null;
        var adjust = self.data('easypiechart-adjust') || null;

        if(max === null) {
            max = data.max;
            state.easyPieChartMax = null;
        }
        else
            state.easyPieChartMax = max;

        var pcent = NETDATA.percentFromValueMax(value, max);

        chart.data('data-percent', pcent);

        var size;
        switch(adjust) {
            case 'width': size = state.chartHeight(); break;
            case 'min': size = Math.min(state.chartWidth(), state.chartHeight()); break;
            case 'max': size = Math.max(state.chartWidth(), state.chartHeight()); break;
            case 'height':
            default: size = state.chartWidth(); break;
        }
        state.element.style.width = size + 'px';
        state.element.style.height = size + 'px';

        var stroke = Math.floor(size / 22);
        if(stroke < 3) stroke = 2;

        var valuefontsize = Math.floor((size * 2 / 3) / 5);
        var valuetop = Math.round((size - valuefontsize - (size / 40)) / 2);
        state.easyPieChartLabel = document.createElement('span');
        state.easyPieChartLabel.className = 'easyPieChartLabel';
        state.easyPieChartLabel.innerHTML = state.legendFormatValue(value);
        state.easyPieChartLabel.style.fontSize = valuefontsize + 'px';
        state.easyPieChartLabel.style.top = valuetop.toString() + 'px';
        state.element_chart.appendChild(state.easyPieChartLabel);

        var titlefontsize = Math.round(valuefontsize * 1.6 / 3);
        var titletop = Math.round(valuetop - (titlefontsize * 2) - (size / 40));
        state.easyPieChartTitle = document.createElement('span');
        state.easyPieChartTitle.className = 'easyPieChartTitle';
        state.easyPieChartTitle.innerHTML = state.title;
        state.easyPieChartTitle.style.fontSize = titlefontsize + 'px';
        state.easyPieChartTitle.style.lineHeight = titlefontsize + 'px';
        state.easyPieChartTitle.style.top = titletop.toString() + 'px';
        state.element_chart.appendChild(state.easyPieChartTitle);

        var unitfontsize = Math.round(titlefontsize * 0.9);
        var unittop = Math.round(valuetop + (valuefontsize + unitfontsize) + (size / 40));
        state.easyPieChartUnits = document.createElement('span');
        state.easyPieChartUnits.className = 'easyPieChartUnits';
        state.easyPieChartUnits.innerHTML = state.units;
        state.easyPieChartUnits.style.fontSize = unitfontsize + 'px';
        state.easyPieChartUnits.style.top = unittop.toString() + 'px';
        state.element_chart.appendChild(state.easyPieChartUnits);

        chart.easyPieChart({
            barColor: self.data('easypiechart-barcolor') || state.chartColors()[0], //'#ef1e25',
            trackColor: self.data('easypiechart-trackcolor') || NETDATA.themes.current.easypiechart_track,
            scaleColor: self.data('easypiechart-scalecolor') || NETDATA.themes.current.easypiechart_scale,
            scaleLength: self.data('easypiechart-scalelength') || 5,
            lineCap: self.data('easypiechart-linecap') || 'round',
            lineWidth: self.data('easypiechart-linewidth') || stroke,
            trackWidth: self.data('easypiechart-trackwidth') || undefined,
            size: self.data('easypiechart-size') || size,
            rotate: self.data('easypiechart-rotate') || 0,
            animate: self.data('easypiechart-rotate') || {duration: 500, enabled: true},
            easing: self.data('easypiechart-easing') || undefined
        });

        // when we just re-create the chart
        // do not animate the first update
        var animate = true;
        if(typeof state.easyPieChart_instance !== 'undefined')
            animate = false;

        state.easyPieChart_instance = chart.data('easyPieChart');
        if(animate === false) state.easyPieChart_instance.disableAnimation();
        state.easyPieChart_instance.update(pcent);
        if(animate === false) state.easyPieChart_instance.enableAnimation();
        return true;
    };

    // ----------------------------------------------------------------------------------------------------------------
    // gauge.js

    NETDATA.gaugeInitialize = function(callback) {
        if(typeof netdataNoGauge === 'undefined' || !netdataNoGauge) {
            $.ajax({
                url: NETDATA.gauge_js,
                cache: true,
                dataType: "script",
                xhrFields: { withCredentials: true } // required for the cookie
            })
                .done(function() {
                    NETDATA.registerChartLibrary('gauge', NETDATA.gauge_js);
                })
                .fail(function() {
                    NETDATA.chartLibraries.gauge.enabled = false;
                    NETDATA.error(100, NETDATA.gauge_js);
                })
                .always(function() {
                    if(typeof callback === "function")
                        callback();
                })
        }
        else {
            NETDATA.chartLibraries.gauge.enabled = false;
            if(typeof callback === "function")
                callback();
        }
    };

    NETDATA.gaugeAnimation = function(state, status) {
        var speed = 32;

        if(typeof status === 'boolean' && status === false)
            speed = 1000000000;
        else if(typeof status === 'number')
            speed = status;

        state.gauge_instance.animationSpeed = speed;
        state.___gaugeOld__.speed = speed;
    };

    NETDATA.gaugeSet = function(state, value, min, max) {
        if(typeof value !== 'number') value = 0;
        if(typeof min !== 'number') min = 0;
        if(typeof max !== 'number') max = 0;
        if(value > max) max = value;
        if(value < min) min = value;
        if(min > max) {
            var t = min;
            min = max;
            max = t;
        }
        else if(min == max)
            max = min + 1;

        // gauge.js has an issue if the needle
        // is smaller than min or larger than max
        // when we set the new values
        // the needle will go crazy

        // to prevent it, we always feed it
        // with a percentage, so that the needle
        // is always between min and max
        var pcent = (value - min) * 100 / (max - min);

        // these should never happen
        if(pcent < 0) pcent = 0;
        if(pcent > 100) pcent = 100;

        state.gauge_instance.set(pcent);

        state.___gaugeOld__.value = value;
        state.___gaugeOld__.min = min;
        state.___gaugeOld__.max = max;
    };

    NETDATA.gaugeSetLabels = function(state, value, min, max) {
        if(state.___gaugeOld__.valueLabel !== value) {
            state.___gaugeOld__.valueLabel = value;
            state.gaugeChartLabel.innerHTML = state.legendFormatValue(value);
        }
        if(state.___gaugeOld__.minLabel !== min) {
            state.___gaugeOld__.minLabel = min;
            state.gaugeChartMin.innerHTML = state.legendFormatValue(min);
        }
        if(state.___gaugeOld__.maxLabel !== max) {
            state.___gaugeOld__.maxLabel = max;
            state.gaugeChartMax.innerHTML = state.legendFormatValue(max);
        }
    };

    NETDATA.gaugeClearSelection = function(state) {
        if(typeof state.gaugeEvent !== 'undefined') {
            if(state.gaugeEvent.timer !== null)
                clearTimeout(state.gaugeEvent.timer);

            state.gaugeEvent.timer = null;
        }

        if(state.isAutoRefreshable() === true && state.data !== null) {
            NETDATA.gaugeChartUpdate(state, state.data);
        }
        else {
            NETDATA.gaugeAnimation(state, false);
            NETDATA.gaugeSet(state, null, null, null);
            NETDATA.gaugeSetLabels(state, null, null, null);
        }

        NETDATA.gaugeAnimation(state, true);
        return true;
    };

    NETDATA.gaugeSetSelection = function(state, t) {
        if(state.timeIsVisible(t) !== true)
            return NETDATA.gaugeClearSelection(state);

        var slot = state.calculateRowForTime(t);
        if(slot < 0 || slot >= state.data.result.length)
            return NETDATA.gaugeClearSelection(state);

        if(typeof state.gaugeEvent === 'undefined') {
            state.gaugeEvent = {
                timer: null,
                value: 0,
                min: 0,
                max: 0
            };
        }

        var value = state.data.result[state.data.result.length - 1 - slot];
        var max = (state.gaugeMax === null)?state.data.max:state.gaugeMax;
        var min = 0;

        state.gaugeEvent.value = value;
        state.gaugeEvent.max = max;
        state.gaugeEvent.min = min;
        NETDATA.gaugeSetLabels(state, value, min, max);

        if(state.gaugeEvent.timer === null) {
            NETDATA.gaugeAnimation(state, false);

            state.gaugeEvent.timer = setTimeout(function() {
                state.gaugeEvent.timer = null;
                NETDATA.gaugeSet(state, state.gaugeEvent.value, state.gaugeEvent.min, state.gaugeEvent.max);
            }, NETDATA.options.current.charts_selection_animation_delay);
        }

        return true;
    };

    NETDATA.gaugeChartUpdate = function(state, data) {
        var value, min, max;

        if(NETDATA.globalPanAndZoom.isActive() === true || state.isAutoRefreshable() === false) {
            value = 0;
            min = 0;
            max = 1;
            NETDATA.gaugeSetLabels(state, null, null, null);
        }
        else {
            value = data.result[0];
            min = 0;
            max = (state.gaugeMax === null)?data.max:state.gaugeMax;
            if(value > max) max = value;
            NETDATA.gaugeSetLabels(state, value, min, max);
        }

        NETDATA.gaugeSet(state, value, min, max);
        return true;
    };

    NETDATA.gaugeChartCreate = function(state, data) {
        var self = $(state.element);
        // var chart = $(state.element_chart);

        var value = data.result[0];
        var max = self.data('gauge-max-value') || null;
        var adjust = self.data('gauge-adjust') || null;
        var pointerColor = self.data('gauge-pointer-color') || NETDATA.themes.current.gauge_pointer;
        var strokeColor = self.data('gauge-stroke-color') || NETDATA.themes.current.gauge_stroke;
        var startColor = self.data('gauge-start-color') || state.chartColors()[0];
        var stopColor = self.data('gauge-stop-color') || void 0;
        var generateGradient = self.data('gauge-generate-gradient') || false;

        if(max === null) {
            max = data.max;
            state.gaugeMax = null;
        }
        else
            state.gaugeMax = max;

        var width = state.chartWidth(), height = state.chartHeight(); //, ratio = 1.5;
        //switch(adjust) {
        //  case 'width': width = height * ratio; break;
        //  case 'height':
        //  default: height = width / ratio; break;
        //}
        //state.element.style.width = width.toString() + 'px';
        //state.element.style.height = height.toString() + 'px';

        var lum_d = 0.05;

        var options = {
            lines: 12,                  // The number of lines to draw
            angle: 0.15,                // The length of each line
            lineWidth: 0.44,            // 0.44 The line thickness
            pointer: {
                length: 0.8,            // 0.9 The radius of the inner circle
                strokeWidth: 0.035,     // The rotation offset
                color: pointerColor     // Fill color
            },
            colorStart: startColor,     // Colors
            colorStop: stopColor,       // just experiment with them
            strokeColor: strokeColor,   // to see which ones work best for you
            limitMax: true,
            generateGradient: (generateGradient === true)?true:false,
            gradientType: 0
        };

        if (generateGradient.constructor === Array) {
            // example options:
            // data-gauge-generate-gradient="[0, 50, 100]"
            // data-gauge-gradient-percent-color-0="#FFFFFF"
            // data-gauge-gradient-percent-color-50="#999900"
            // data-gauge-gradient-percent-color-100="#000000"

            options.percentColors = new Array();
            var len = generateGradient.length;
            while(len--) {
                var pcent = generateGradient[len];
                var color = self.data('gauge-gradient-percent-color-' + pcent.toString()) || false;
                if(color !== false) {
                    var a = new Array();
                    a[0] = pcent / 100;
                    a[1] = color;
                    options.percentColors.unshift(a);
                }
            }
            if(options.percentColors.length === 0)
                delete options.percentColors;
        }
        else if(generateGradient === false && NETDATA.themes.current.gauge_gradient === true) {
            options.percentColors = [
                [0.0, NETDATA.colorLuminance(startColor, (lum_d * 10) - (lum_d * 0))],
                [0.1, NETDATA.colorLuminance(startColor, (lum_d * 10) - (lum_d * 1))],
                [0.2, NETDATA.colorLuminance(startColor, (lum_d * 10) - (lum_d * 2))],
                [0.3, NETDATA.colorLuminance(startColor, (lum_d * 10) - (lum_d * 3))],
                [0.4, NETDATA.colorLuminance(startColor, (lum_d * 10) - (lum_d * 4))],
                [0.5, NETDATA.colorLuminance(startColor, (lum_d * 10) - (lum_d * 5))],
                [0.6, NETDATA.colorLuminance(startColor, (lum_d * 10) - (lum_d * 6))],
                [0.7, NETDATA.colorLuminance(startColor, (lum_d * 10) - (lum_d * 7))],
                [0.8, NETDATA.colorLuminance(startColor, (lum_d * 10) - (lum_d * 8))],
                [0.9, NETDATA.colorLuminance(startColor, (lum_d * 10) - (lum_d * 9))],
                [1.0, NETDATA.colorLuminance(startColor, 0.0)]];
        }

        state.gauge_canvas = document.createElement('canvas');
        state.gauge_canvas.id = 'gauge-' + state.uuid + '-canvas';
        state.gauge_canvas.className = 'gaugeChart';
        state.gauge_canvas.width  = width;
        state.gauge_canvas.height = height;
        state.element_chart.appendChild(state.gauge_canvas);

        var valuefontsize = Math.floor(height / 6);
        var valuetop = Math.round((height - valuefontsize - (height / 6)) / 2);
        state.gaugeChartLabel = document.createElement('span');
        state.gaugeChartLabel.className = 'gaugeChartLabel';
        state.gaugeChartLabel.style.fontSize = valuefontsize + 'px';
        state.gaugeChartLabel.style.top = valuetop.toString() + 'px';
        state.element_chart.appendChild(state.gaugeChartLabel);

        var titlefontsize = Math.round(valuefontsize / 2);
        var titletop = 0;
        state.gaugeChartTitle = document.createElement('span');
        state.gaugeChartTitle.className = 'gaugeChartTitle';
        state.gaugeChartTitle.innerHTML = state.title;
        state.gaugeChartTitle.style.fontSize = titlefontsize + 'px';
        state.gaugeChartTitle.style.lineHeight = titlefontsize + 'px';
        state.gaugeChartTitle.style.top = titletop.toString() + 'px';
        state.element_chart.appendChild(state.gaugeChartTitle);

        var unitfontsize = Math.round(titlefontsize * 0.9);
        state.gaugeChartUnits = document.createElement('span');
        state.gaugeChartUnits.className = 'gaugeChartUnits';
        state.gaugeChartUnits.innerHTML = state.units;
        state.gaugeChartUnits.style.fontSize = unitfontsize + 'px';
        state.element_chart.appendChild(state.gaugeChartUnits);

        state.gaugeChartMin = document.createElement('span');
        state.gaugeChartMin.className = 'gaugeChartMin';
        state.gaugeChartMin.style.fontSize = Math.round(valuefontsize * 0.75).toString() + 'px';
        state.element_chart.appendChild(state.gaugeChartMin);

        state.gaugeChartMax = document.createElement('span');
        state.gaugeChartMax.className = 'gaugeChartMax';
        state.gaugeChartMax.style.fontSize = Math.round(valuefontsize * 0.75).toString() + 'px';
        state.element_chart.appendChild(state.gaugeChartMax);

        // when we just re-create the chart
        // do not animate the first update
        var animate = true;
        if(typeof state.gauge_instance !== 'undefined')
            animate = false;

        state.gauge_instance = new Gauge(state.gauge_canvas).setOptions(options); // create sexy gauge!

        state.___gaugeOld__ = {
            value: value,
            min: 0,
            max: max,
            valueLabel: null,
            minLabel: null,
            maxLabel: null
        };

        // we will always feed a percentage
        state.gauge_instance.minValue = 0;
        state.gauge_instance.maxValue = 100;

        NETDATA.gaugeAnimation(state, animate);
        NETDATA.gaugeSet(state, value, 0, max);
        NETDATA.gaugeSetLabels(state, value, 0, max);
        NETDATA.gaugeAnimation(state, true);
        return true;
    };

    // ----------------------------------------------------------------------------------------------------------------
    // Charts Libraries Registration

    NETDATA.chartLibraries = {
        "dygraph": {
            initialize: NETDATA.dygraphInitialize,
            create: NETDATA.dygraphChartCreate,
            update: NETDATA.dygraphChartUpdate,
            resize: function(state) {
                if(typeof state.dygraph_instance.resize === 'function')
                    state.dygraph_instance.resize();
            },
            setSelection: NETDATA.dygraphSetSelection,
            clearSelection:  NETDATA.dygraphClearSelection,
            toolboxPanAndZoom: NETDATA.dygraphToolboxPanAndZoom,
            initialized: false,
            enabled: true,
            format: function(state) { return 'json'; },
            options: function(state) { return 'ms|flip'; },
            legend: function(state) {
                if(this.isSparkline(state) === false)
                    return 'right-side';
                else
                    return null;
            },
            autoresize: function(state) { return true; },
            max_updates_to_recreate: function(state) { return 5000; },
            track_colors: function(state) { return true; },
            pixels_per_point: function(state) {
                if(this.isSparkline(state) === false)
                    return 3;
                else
                    return 2;
            },

            isSparkline: function(state) {
                if(typeof state.dygraph_sparkline === 'undefined') {
                    var t = $(state.element).data('dygraph-theme');
                    if(t === 'sparkline')
                        state.dygraph_sparkline = true;
                    else
                        state.dygraph_sparkline = false;
                }
                return state.dygraph_sparkline;
            }
        },
        "sparkline": {
            initialize: NETDATA.sparklineInitialize,
            create: NETDATA.sparklineChartCreate,
            update: NETDATA.sparklineChartUpdate,
            resize: null,
            setSelection: undefined, // function(state, t) { return true; },
            clearSelection: undefined, // function(state) { return true; },
            toolboxPanAndZoom: null,
            initialized: false,
            enabled: true,
            format: function(state) { return 'array'; },
            options: function(state) { return 'flip|abs'; },
            legend: function(state) { return null; },
            autoresize: function(state) { return false; },
            max_updates_to_recreate: function(state) { return 5000; },
            track_colors: function(state) { return false; },
            pixels_per_point: function(state) { return 3; }
        },
        "peity": {
            initialize: NETDATA.peityInitialize,
            create: NETDATA.peityChartCreate,
            update: NETDATA.peityChartUpdate,
            resize: null,
            setSelection: undefined, // function(state, t) { return true; },
            clearSelection: undefined, // function(state) { return true; },
            toolboxPanAndZoom: null,
            initialized: false,
            enabled: true,
            format: function(state) { return 'ssvcomma'; },
            options: function(state) { return 'null2zero|flip|abs'; },
            legend: function(state) { return null; },
            autoresize: function(state) { return false; },
            max_updates_to_recreate: function(state) { return 5000; },
            track_colors: function(state) { return false; },
            pixels_per_point: function(state) { return 3; }
        },
        "morris": {
            initialize: NETDATA.morrisInitialize,
            create: NETDATA.morrisChartCreate,
            update: NETDATA.morrisChartUpdate,
            resize: null,
            setSelection: undefined, // function(state, t) { return true; },
            clearSelection: undefined, // function(state) { return true; },
            toolboxPanAndZoom: null,
            initialized: false,
            enabled: true,
            format: function(state) { return 'json'; },
            options: function(state) { return 'objectrows|ms'; },
            legend: function(state) { return null; },
            autoresize: function(state) { return false; },
            max_updates_to_recreate: function(state) { return 50; },
            track_colors: function(state) { return false; },
            pixels_per_point: function(state) { return 15; }
        },
        "google": {
            initialize: NETDATA.googleInitialize,
            create: NETDATA.googleChartCreate,
            update: NETDATA.googleChartUpdate,
            resize: null,
            setSelection: undefined, //function(state, t) { return true; },
            clearSelection: undefined, //function(state) { return true; },
            toolboxPanAndZoom: null,
            initialized: false,
            enabled: true,
            format: function(state) { return 'datatable'; },
            options: function(state) { return ''; },
            legend: function(state) { return null; },
            autoresize: function(state) { return false; },
            max_updates_to_recreate: function(state) { return 300; },
            track_colors: function(state) { return false; },
            pixels_per_point: function(state) { return 4; }
        },
        "raphael": {
            initialize: NETDATA.raphaelInitialize,
            create: NETDATA.raphaelChartCreate,
            update: NETDATA.raphaelChartUpdate,
            resize: null,
            setSelection: undefined, // function(state, t) { return true; },
            clearSelection: undefined, // function(state) { return true; },
            toolboxPanAndZoom: null,
            initialized: false,
            enabled: true,
            format: function(state) { return 'json'; },
            options: function(state) { return ''; },
            legend: function(state) { return null; },
            autoresize: function(state) { return false; },
            max_updates_to_recreate: function(state) { return 5000; },
            track_colors: function(state) { return false; },
            pixels_per_point: function(state) { return 3; }
        },
        "c3": {
            initialize: NETDATA.c3Initialize,
            create: NETDATA.c3ChartCreate,
            update: NETDATA.c3ChartUpdate,
            resize: null,
            setSelection: undefined, // function(state, t) { return true; },
            clearSelection: undefined, // function(state) { return true; },
            toolboxPanAndZoom: null,
            initialized: false,
            enabled: true,
            format: function(state) { return 'csvjsonarray'; },
            options: function(state) { return 'milliseconds'; },
            legend: function(state) { return null; },
            autoresize: function(state) { return false; },
            max_updates_to_recreate: function(state) { return 5000; },
            track_colors: function(state) { return false; },
            pixels_per_point: function(state) { return 15; }
        },
        "d3": {
            initialize: NETDATA.d3Initialize,
            create: NETDATA.d3ChartCreate,
            update: NETDATA.d3ChartUpdate,
            resize: null,
            setSelection: undefined, // function(state, t) { return true; },
            clearSelection: undefined, // function(state) { return true; },
            toolboxPanAndZoom: null,
            initialized: false,
            enabled: true,
            format: function(state) { return 'json'; },
            options: function(state) { return ''; },
            legend: function(state) { return null; },
            autoresize: function(state) { return false; },
            max_updates_to_recreate: function(state) { return 5000; },
            track_colors: function(state) { return false; },
            pixels_per_point: function(state) { return 3; }
        },
        "easypiechart": {
            initialize: NETDATA.easypiechartInitialize,
            create: NETDATA.easypiechartChartCreate,
            update: NETDATA.easypiechartChartUpdate,
            resize: null,
            setSelection: NETDATA.easypiechartSetSelection,
            clearSelection: NETDATA.easypiechartClearSelection,
            toolboxPanAndZoom: null,
            initialized: false,
            enabled: true,
            format: function(state) { return 'array'; },
            options: function(state) { return 'absolute'; },
            legend: function(state) { return null; },
            autoresize: function(state) { return false; },
            max_updates_to_recreate: function(state) { return 5000; },
            track_colors: function(state) { return true; },
            pixels_per_point: function(state) { return 3; },
            aspect_ratio: 100
        },
        "gauge": {
            initialize: NETDATA.gaugeInitialize,
            create: NETDATA.gaugeChartCreate,
            update: NETDATA.gaugeChartUpdate,
            resize: null,
            setSelection: NETDATA.gaugeSetSelection,
            clearSelection: NETDATA.gaugeClearSelection,
            toolboxPanAndZoom: null,
            initialized: false,
            enabled: true,
            format: function(state) { return 'array'; },
            options: function(state) { return 'absolute'; },
            legend: function(state) { return null; },
            autoresize: function(state) { return false; },
            max_updates_to_recreate: function(state) { return 5000; },
            track_colors: function(state) { return true; },
            pixels_per_point: function(state) { return 3; },
            aspect_ratio: 70
        }
    };

    NETDATA.registerChartLibrary = function(library, url) {
        if(NETDATA.options.debug.libraries === true)
            console.log("registering chart library: " + library);

        NETDATA.chartLibraries[library].url = url;
        NETDATA.chartLibraries[library].initialized = true;
        NETDATA.chartLibraries[library].enabled = true;
    };

    // ----------------------------------------------------------------------------------------------------------------
    // Load required JS libraries and CSS

    NETDATA.requiredJs = [
        {
            url: NETDATA.serverDefault + 'lib/bootstrap.min.js',
            isAlreadyLoaded: function() {
                // check if bootstrap is loaded
                if(typeof $().emulateTransitionEnd == 'function')
                    return true;
                else {
                    if(typeof netdataNoBootstrap !== 'undefined' && netdataNoBootstrap)
                        return true;
                    else
                        return false;
                }
            }
        },
        {
            url: NETDATA.serverDefault + 'lib/jquery.nanoscroller.min.js',
            isAlreadyLoaded: function() { return false; }
        },
        {
            url: NETDATA.serverDefault + 'lib/bootstrap-toggle.min.js',
            isAlreadyLoaded: function() { return false; }
        }
    ];

    NETDATA.requiredCSS = [
        {
            url: NETDATA.themes.current.bootstrap_css,
            isAlreadyLoaded: function() {
                if(typeof netdataNoBootstrap !== 'undefined' && netdataNoBootstrap)
                    return true;
                else
                    return false;
            }
        },
        {
            url: NETDATA.serverDefault + 'css/font-awesome.min.css',
            isAlreadyLoaded: function() { return false; }
        },
        {
            url: NETDATA.themes.current.dashboard_css,
            isAlreadyLoaded: function() { return false; }
        },
        {
            url: NETDATA.serverDefault + 'css/bootstrap-toggle.min.css',
            isAlreadyLoaded: function() { return false; }
        }
    ];

    NETDATA.loadRequiredJs = function(index, callback) {
        if(index >= NETDATA.requiredJs.length)  {
            if(typeof callback === 'function')
                callback();
            return;
        }

        if(NETDATA.requiredJs[index].isAlreadyLoaded()) {
            NETDATA.loadRequiredJs(++index, callback);
            return;
        }

        if(NETDATA.options.debug.main_loop === true)
            console.log('loading ' + NETDATA.requiredJs[index].url);

        $.ajax({
            url: NETDATA.requiredJs[index].url,
            cache: true,
            dataType: "script",
            xhrFields: { withCredentials: true } // required for the cookie
        })
        .success(function() {
            if(NETDATA.options.debug.main_loop === true)
                console.log('loaded ' + NETDATA.requiredJs[index].url);

            NETDATA.loadRequiredJs(++index, callback);
        })
        .fail(function() {
            alert('Cannot load required JS library: ' + NETDATA.requiredJs[index].url);
        })
    };

    NETDATA.loadRequiredCSS = function(index) {
        if(index >= NETDATA.requiredCSS.length)
            return;

        if(NETDATA.requiredCSS[index].isAlreadyLoaded()) {
            NETDATA.loadRequiredCSS(++index);
            return;
        }

        if(NETDATA.options.debug.main_loop === true)
            console.log('loading ' + NETDATA.requiredCSS[index].url);

        NETDATA._loadCSS(NETDATA.requiredCSS[index].url);
        NETDATA.loadRequiredCSS(++index);
    };


    // ----------------------------------------------------------------------------------------------------------------
    // Registry of netdata hosts

    NETDATA.alarms = {
        current: null,
        callback: null,

        get: function(what, callback) {
            $.ajax({
                url: NETDATA.serverDefault + '/api/v1/alarms?' + what.toString(),
                async: true,
                cache: false,
                xhrFields: { withCredentials: true } // required for the cookie
            })
                .done(function(data) {
                    if(typeof callback === 'function')
                        callback(data);
                })
                .fail(function() {
                    NETDATA.error(415, host);

                    if(typeof callback === 'function')
                        callback(null);
                });
        },

        update_forever: function() {
            NETDATA.alarms.get('active', function(data) {
                if(data !== null) {
                    NETDATA.alarms.current = data;

                    if (typeof NETDATA.alarms.callback === 'function') {
                        NETDATA.alarms.callback(data);
                    }
                }

                setTimeout(NETDATA.alarms.update_forever, 10000);
            });
        },

        get_log: function(callback) {
            $.ajax({
                url: NETDATA.serverDefault + '/api/v1/alarm_log',
                async: true,
                cache: false,
                xhrFields: { withCredentials: true } // required for the cookie
            })
                .done(function(data) {
                    if(typeof callback === 'function')
                        callback(data);
                })
                .fail(function() {
                    NETDATA.error(416, host);

                    if(typeof callback === 'function')
                        callback(null);
                });
        },

        init: function() {
            NETDATA.alarms.update_forever();
        }
    };

    // ----------------------------------------------------------------------------------------------------------------
    // Registry of netdata hosts

    NETDATA.registry = {
        server: null,       // the netdata registry server
        person_guid: null,  // the unique ID of this browser / user
        machine_guid: null, // the unique ID the netdata server that served dashboard.js
        hostname: null,     // the hostname of the netdata server that served dashboard.js
        machines: null,         // the user's other URLs
        machines_array: null,   // the user's other URLs in an array
        person_urls: null,

        parsePersonUrls: function(person_urls) {
            // console.log(person_urls);
            NETDATA.registry.person_urls = person_urls;

            if(person_urls) {
                NETDATA.registry.machines = {};
                NETDATA.registry.machines_array = new Array();

                var now = new Date().getTime();
                var apu = person_urls;
                var i = apu.length;
                while(i--) {
                    if(typeof NETDATA.registry.machines[apu[i][0]] === 'undefined') {
                        // console.log('adding: ' + apu[i][4] + ', ' + ((now - apu[i][2]) / 1000).toString());

                        var obj = {
                            guid: apu[i][0],
                            url: apu[i][1],
                            last_t: apu[i][2],
                            accesses: apu[i][3],
                            name: apu[i][4],
                            alternate_urls: new Array()
                        };
                        obj.alternate_urls.push(apu[i][1]);

                        NETDATA.registry.machines[apu[i][0]] = obj;
                        NETDATA.registry.machines_array.push(obj);
                    }
                    else {
                        // console.log('appending: ' + apu[i][4] + ', ' + ((now - apu[i][2]) / 1000).toString());

                        var pu = NETDATA.registry.machines[apu[i][0]];
                        if(pu.last_t < apu[i][2]) {
                            pu.url = apu[i][1];
                            pu.last_t = apu[i][2];
                            pu.name = apu[i][4];
                        }
                        pu.accesses += apu[i][3];
                        pu.alternate_urls.push(apu[i][1]);
                    }
                }
            }

            if(typeof netdataRegistryCallback === 'function')
                netdataRegistryCallback(NETDATA.registry.machines_array);
        },

        init: function() {
            if(typeof netdataNoRegistry !== 'undefined' && netdataNoRegistry)
                return;

            NETDATA.registry.hello(NETDATA.serverDefault, function(data) {
                if(data) {
                    NETDATA.registry.server = data.registry;
                    NETDATA.registry.machine_guid = data.machine_guid;
                    NETDATA.registry.hostname = data.hostname;

                    NETDATA.registry.access(2, function (person_urls) {
                        NETDATA.registry.parsePersonUrls(person_urls);

                    });
                }
            });
        },

        hello: function(host, callback) {
            while(host.slice(-1) === '/')
                host = host.substring(0, host.length - 1);

            // send HELLO to a netdata server:
            // 1. verifies the server is reachable
            // 2. responds with the registry URL, the machine GUID of this netdata server and its hostname
            $.ajax({
                    url: host + '/api/v1/registry?action=hello',
                    async: true,
                    cache: false,
                    xhrFields: { withCredentials: true } // required for the cookie
                })
                .done(function(data) {
                    if(typeof data.status !== 'string' || data.status !== 'ok') {
                        NETDATA.error(408, host + ' response: ' + JSON.stringify(data));
                        data = null;
                    }

                    if(typeof callback === 'function')
                        callback(data);
                })
                .fail(function() {
                    NETDATA.error(407, host);

                    if(typeof callback === 'function')
                        callback(null);
                });
        },

        access: function(max_redirects, callback) {
            // send ACCESS to a netdata registry:
            // 1. it lets it know we are accessing a netdata server (its machine GUID and its URL)
            // 2. it responds with a list of netdata servers we know
            // the registry identifies us using a cookie it sets the first time we access it
            // the registry may respond with a redirect URL to send us to another registry
            $.ajax({
                    url: NETDATA.registry.server + '/api/v1/registry?action=access&machine=' + NETDATA.registry.machine_guid + '&name=' + encodeURIComponent(NETDATA.registry.hostname) + '&url=' + encodeURIComponent(NETDATA.serverDefault), // + '&visible_url=' + encodeURIComponent(document.location),
                    async: true,
                    cache: false,
                    xhrFields: { withCredentials: true } // required for the cookie
                })
                .done(function(data) {
                    var redirect = null;
                    if(typeof data.registry === 'string')
                        redirect = data.registry;

                    if(typeof data.status !== 'string' || data.status !== 'ok') {
                        NETDATA.error(409, NETDATA.registry.server + ' responded with: ' + JSON.stringify(data));
                        data = null;
                    }

                    if(data === null) {
                        if(redirect !== null && max_redirects > 0) {
                            NETDATA.registry.server = redirect;
                            NETDATA.registry.access(max_redirects - 1, callback);
                        }
                        else {
                            if(typeof callback === 'function')
                                callback(null);
                        }
                    }
                    else {
                        if(typeof data.person_guid === 'string')
                            NETDATA.registry.person_guid = data.person_guid;

                        if(typeof callback === 'function')
                            callback(data.urls);
                    }
                })
                .fail(function() {
                    NETDATA.error(410, NETDATA.registry.server);

                    if(typeof callback === 'function')
                        callback(null);
                });
        },

        delete: function(delete_url, callback) {
            // send DELETE to a netdata registry:
            $.ajax({
                url: NETDATA.registry.server + '/api/v1/registry?action=delete&machine=' + NETDATA.registry.machine_guid + '&name=' + encodeURIComponent(NETDATA.registry.hostname) + '&url=' + encodeURIComponent(NETDATA.serverDefault) + '&delete_url=' + encodeURIComponent(delete_url),
                async: true,
                cache: false,
                xhrFields: { withCredentials: true } // required for the cookie
            })
                .done(function(data) {
                    if(typeof data.status !== 'string' || data.status !== 'ok') {
                        NETDATA.error(411, NETDATA.registry.server + ' responded with: ' + JSON.stringify(data));
                        data = null;
                    }

                    if(typeof callback === 'function')
                        callback(data);
                })
                .fail(function() {
                    NETDATA.error(412, NETDATA.registry.server);

                    if(typeof callback === 'function')
                        callback(null);
                });
        },

        switch: function(new_person_guid, callback) {
            // impersonate
            $.ajax({
                url: NETDATA.registry.server + '/api/v1/registry?action=switch&machine=' + NETDATA.registry.machine_guid + '&name=' + encodeURIComponent(NETDATA.registry.hostname) + '&url=' + encodeURIComponent(NETDATA.serverDefault) + '&to=' + new_person_guid,
                async: true,
                cache: false,
                xhrFields: { withCredentials: true } // required for the cookie
            })
                .done(function(data) {
                    if(typeof data.status !== 'string' || data.status !== 'ok') {
                        NETDATA.error(413, NETDATA.registry.server + ' responded with: ' + JSON.stringify(data));
                        data = null;
                    }

                    if(typeof callback === 'function')
                        callback(data);
                })
                .fail(function() {
                    NETDATA.error(414, NETDATA.registry.server);

                    if(typeof callback === 'function')
                        callback(null);
                });
        }
    };

    // ----------------------------------------------------------------------------------------------------------------
    // Boot it!

    NETDATA.errorReset();
    NETDATA.loadRequiredCSS(0);

    NETDATA._loadjQuery(function() {
        NETDATA.loadRequiredJs(0, function() {
            if(typeof $().emulateTransitionEnd !== 'function') {
                // bootstrap is not available
                NETDATA.options.current.show_help = false;
            }

            if(typeof netdataDontStart === 'undefined' || !netdataDontStart) {
                if(NETDATA.options.debug.main_loop === true)
                    console.log('starting chart refresh thread');

                NETDATA.start();
            }
        });
    });

    // window.NETDATA = NETDATA;
// })(window, document);
