--!A cross-platform build utility based on Lua
--
-- Licensed under the Apache License, Version 2.0 (the "License");
-- you may not use this file except in compliance with the License.
-- You may obtain a copy of the License at
--
--     http://www.apache.org/licenses/LICENSE-2.0
--
-- Unless required by applicable law or agreed to in writing, software
-- distributed under the License is distributed on an "AS IS" BASIS,
-- WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-- See the License for the specific language governing permissions and
-- limitations under the License.
--
-- Copyright (C) 2015-present, TBOOX Open Source Group.
--
-- @author      OpportunityLiu
-- @file        progress.lua
--

-- imports
import("core.base.option")
import("core.base.object")
import("core.base.colors")
import("core.base.tty")
import("core.theme.theme")

-- define module
local process = process or object { _init = { "_RUNNING", "_INDEX", "_STREAM", "_OPT" } }

-- stop the progress indicator, clear written frames
function process:stop()
    if self._RUNNING ~= 0 then
        self:clear()
        self._RUNNING = 0
        self._INDEX = 0
    end
end

function process:_clear()
    if self._RUNNING == 1 then
        tty.erase_line_to_end()
        self._RUNNING = 2
        return true
    end
end

-- clear previous frame of the progress indicator
function process:clear()
    if self:_clear() then
        self._STREAM:flush()
    end
end

-- write next frame of the progress indicator
function process:write()
    local chars = self._OPT.chars[self._INDEX % #self._OPT.chars + 1]
    tty.cursor_and_attrs_save()
    self._STREAM:write(chars)
    self._STREAM:flush()
    tty.cursor_and_attrs_restore()
    self._INDEX = self._INDEX + 1
    self._RUNNING = 1
end

-- check if the progress indicator is running
function process:running()
    return self._RUNNING and true or false
end

-- showing progress line without scroll?
function showing_without_scroll()
    return _g.showing_without_scroll
end

-- show the message with process
function show(progress, format, ...)
    progress = math.floor(progress)
    local progress_prefix = "${color.build.progress}" .. theme.get("text.build.progress_format") .. ":${clear} "
    if option.get("verbose") then
        cprint(progress_prefix .. "${dim}" .. format, progress, ...)
    else
        local is_scroll = _g.is_scroll
        if is_scroll == nil then
            is_scroll = theme.get("text.build.progress_style") == "scroll"
            _g.is_scroll = is_scroll
        end
        if is_scroll then
            cprint(progress_prefix .. format, progress, ...)
        else
            tty.erase_line_to_start().cr()
            local msg = vformat(progress_prefix .. format, progress, ...)
            local msg_plain = colors.translate(msg, {plain = true})
            local maxwidth = os.getwinsize().width
            if #msg_plain <= maxwidth then
                cprintf(msg)
            else
                -- windows width is too small? strip the partial message in middle
                local partlen = math.floor(maxwidth / 2) - 3
                local sep = msg_plain:sub(partlen + 1, #msg_plain - partlen - 1)
                local split = msg:split(sep, {plain = true, strict = true})
                cprintf(table.concat(split, "..."))
            end
            if math.floor(progress) == 100 then
                print("")
                _g.showing_without_scroll = false
            else
                _g.showing_without_scroll = true
            end
            io.flush()
        end
    end
end

-- get the message text with process
function text(progress, format, ...)
    progress = math.floor(progress)
    local progress_prefix = "${color.build.progress}" .. theme.get("text.build.progress_format") .. ":${clear} "
    if option.get("verbose") then
        return string.format(progress_prefix .. "${dim}" .. format, progress, ...)
    else
        return string.format(progress_prefix .. format, progress, ...)
    end
end

-- build a progress indicator
-- @params stream - stream to write to, will use io.stdout if not provided
-- @params opt - options
--               - chars - an array of chars for progress indicator
function new(stream, opt)

    -- set default values
    stream = stream or io.stdout
    opt = opt or {}
    if opt.chars == nil or #opt.chars == 0 then
        opt.chars = theme.get("text.spinner.chars")
    end
    return process {_OPT = opt, _STREAM = stream, _RUNNING = 0, _INDEX = 0}
end
