dotfiles/awesome/music.lua

local naughty = require("naughty")
local wibox = require("wibox")
local awful = require("awful")

local ret = {}
ret.text_widget = wibox.widget.textbox()
ret.text_widget:set_align("right")
ret.text_widget.font = "Ubuntu Mono"

ret.icon_widget = wibox.widget.textbox()
ret.icon_widget:set_align("right")
ret.icon_widget.font = "Ubuntu Mono"


local icon = ""
local total_text = ""
local position = 1
local width = 30
local dots = 3

local function string_starts_with(String,Start)
   return string.sub(String,1,string.len(Start))==Start
end

local function string_split(str, delimiter)
    if str == nil then
        return {}
    end
    local ret = {''}
    count = 1
    for i = 1, string.len(str) do
        local c = str:sub(i,i)
        if c == delimiter then
            count = count + 1
            ret[count] = ''
        else
            ret[count] = ret[count] .. c
        end
    end
    return ret
end

local function pad(str, len, char)
    if char == nil then char = ' ' end
    return str .. string.rep(char, len - #str)
end

local function set_text(text)
    total_text = text

    if string.len(total_text) >= width then
        position = math.floor((width - string.len(total_text)) / 2)
    end
end

ret.execute_command = function(command)

    awful.spawn.easy_async('music-client ' .. command, function(stdout, stderr, reason, code)

        local text = string_split(stdout, '\n')
        local active_command =
            string_starts_with(command, 'file') or
            string_starts_with(command, 'next') or
            string_starts_with(command, 'previous')

        local start_server_command = active_command or
            string_starts_with(command, 'play') or
            string_starts_with(command, 'pause')

        if code == 0 then

            if active_command then
                set_text(text[1])
            elseif string_starts_with(command, 'noop') then
                total_text = text[1]
                position = math.floor((width - string.len(total_text)) / 2)
            end

        elseif start_server_command then
            -- Start the server and re-exec the command
            os.execute('music-server&')
            os.execute('sleep 0.2')
            ret.execute_command('noop')
        else
            set_text('music-server not running')
        end

        if text[2] ~= nil then
            icon = text[2]
        end

    end)

end

function update_widget()
    ret.icon_widget:set_text(' ' .. icon .. ' ')
    if string.len(total_text) < width then
        ret.text_widget:set_text(' ' .. pad(total_text, width + 1, ' '))
    else
        local pos = math.min(position, string.len(total_text) - width)
        pos = math.max(1, pos)
        ret.text_widget:set_text(' ' .. string.sub(total_text, pos, pos + width))
        position = position + 1
        if position > string.len(total_text) then
            position = math.floor((width - string.len(total_text)) / 2)
        end
    end
end

ret.execute_command('noop')

ret.timer = timer({timeout=0.2})
ret.timer:connect_signal("timeout", update_widget)
ret.timer:start()

return ret