/**
 * @fileoverview HTML reporter
 * @author Julian Laval
 */
"use strict";

var lodash = require("lodash");
var fs = require("fs");
var path = require("path");

//------------------------------------------------------------------------------
// Helpers
//------------------------------------------------------------------------------

var pageTemplate = lodash.template(fs.readFileSync(path.join(__dirname, "html-template-page.html"), "utf-8"));
var messageTemplate = lodash.template(fs.readFileSync(path.join(__dirname, "html-template-message.html"), "utf-8"));
var resultTemplate = lodash.template(fs.readFileSync(path.join(__dirname, "html-template-result.html"), "utf-8"));

/**
 * Given a word and a count, append an s if count is not one.
 * @param {string} word A word in its singular form.
 * @param {int} count A number controlling whether word should be pluralized.
 * @returns {string} The original word with an s on the end if count is not one.
 */
function pluralize(word, count) {
    return (count === 1 ? word : word + "s");
}

/**
 * Renders text along the template of x problems (x errors, x warnings)
 * @param {string} totalErrors Total errors
 * @param {string} totalWarnings Total warnings
 * @returns {string} The formatted string, pluralized where necessary
 */
function renderSummary(totalErrors, totalWarnings) {
    var totalProblems = totalErrors + totalWarnings;
    var renderedText = totalProblems + " " + pluralize("problem", totalProblems);

    if (totalProblems !== 0) {
        renderedText += " (" + totalErrors + " " + pluralize("error", totalErrors) + ", " + totalWarnings + " " + pluralize("warning", totalWarnings) + ")";
    }
    return renderedText;
}

/**
 * Get the color based on whether there are errors/warnings...
 * @param {string} totalErrors Total errors
 * @param {string} totalWarnings Total warnings
 * @returns {int} The color code (0 = green, 1 = yellow, 2 = red)
 */
function renderColor(totalErrors, totalWarnings) {
    if (totalErrors !== 0) {
        return 2;
    } else if (totalWarnings !== 0) {
        return 1;
    }
    return 0;
}

/**
 * Get HTML (table rows) describing the messages.
 * @param {Array} messages Messages.
 * @param {int} parentIndex Index of the parent HTML row.
 * @returns {string} HTML (table rows) describing the messages.
 */
function renderMessages(messages, parentIndex) {

    /**
     * Get HTML (table row) describing a message.
     * @param {Object} message Message.
     * @returns {string} HTML (table row) describing a message.
     */
    return lodash.map(messages, function(message) {
        var lineNumber,
            columnNumber;

        lineNumber = message.line || 0;
        columnNumber = message.column || 0;

        return messageTemplate({
            parentIndex: parentIndex,
            lineNumber: lineNumber,
            columnNumber: columnNumber,
            severityNumber: message.severity,
            severityName: message.severity === 1 ? "Warning" : "Error",
            message: message.message,
            ruleId: message.ruleId
        });
    }).join("\n");
}

/**
 * @param {Array} results Test results.
 * @returns {string} HTML string describing the results.
 */
function renderResults(results) {
    return lodash.map(results, function(result, index) {
        return resultTemplate({
            index: index,
            color: renderColor(result.errorCount, result.warningCount),
            filePath: result.filePath,
            summary: renderSummary(result.errorCount, result.warningCount)

        }) + renderMessages(result.messages, index);
    }).join("\n");
}

//------------------------------------------------------------------------------
// Public Interface
//------------------------------------------------------------------------------

module.exports = function(results) {
    var totalErrors,
        totalWarnings;

    totalErrors = 0;
    totalWarnings = 0;

    // Iterate over results to get totals
    results.forEach(function(result) {
        totalErrors += result.errorCount;
        totalWarnings += result.warningCount;
    });

    return pageTemplate({
        date: new Date(),
        reportColor: renderColor(totalErrors, totalWarnings),
        reportSummary: renderSummary(totalErrors, totalWarnings),
        results: renderResults(results)
    });
};
