-- mpc.lua, a dxirc script for controlling the Music Player Daemon
-- Copyright (C) 2010 Jaromir Hradilek <jhradilek@gmail.com>

-- This program is free software:  you can redistribute it and/or modify it
-- under  the terms of the  GNU General Public License  as published by the
-- Free Software Foundation, version 3 of the License.
--
-- This program is  distributed  in the hope  that it will  be useful,  but
-- WITHOUT  ANY WARRANTY;  without  even the implied warranty of MERCHANTA-
-- BILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the  GNU General Public
-- License for more details.
--
-- You should have received a copy of the  GNU General Public License along
-- with this program. If not, see <http://www.gnu.org/licenses/>.

-- Register the script:
function dxirc_Register()
  -- General script information:
  local name        = "mpc"
  local version     = "0.9.0"
  local description = "Control the Music Player Daemon directly from " ..
                      "dxirc and/or send the currently playing track " ..
                      "to the channel/query. Note that mpc has to be " ..
                      "installed in order to run this script."

  -- Return the information:
  return name, version, description
end

-- Register commands:
function dxirc_Init()
  dxirc.AddCommand("mpc", "cmd_mpc","Control the Music Player Daemon. "..
                   "Usage: /MPC [command], where allowed commands are "..
                   "current, play, pause, stop, next or prev.")
end

-- Return the string with currently playing song:
function mpc_current()
  -- Run mpc in a separate process and get the currently playing track:
  local mpc           = io.popen('mpc current', 'r')
  local current_track = mpc:read()
  mpc:close()

  -- Check whether the track name is present:
  if current_track == nil then
    -- Return the MPD status:
    return ".:[ MPD is not playing ]:."
  else
    -- Return the formatted result:
    return ".:[ " .. current_track .. " ]:."
  end
end

-- Play the track:
function mpc_play()
  -- Run mpc in a separate process and return its status code:
  return os.execute('mpc play')
end

-- Pause the track:
function mpc_pause()
  -- Run mpc in a separate process and return its status code:
  return os.execute('mpc pause')
end

-- Stop playing the track:
function mpc_stop()
  -- Run mpc in a separate process and return its status code:
  return os.execute('mpc stop')
end

-- Play previous track:
function mpc_prev()
  -- Run mpc in a separate process and return its status code:
  return os.execute('mpc prev')
end

-- Play next track:
function mpc_next()
  -- Run mpc in a separate process and return its status code:
  return os.execute('mpc next')
end

-- Run mpc with selected command:
function cmd_mpc(arg, tab_id)
  -- Convert the argument to lower case:
  local command = arg:lower()

  -- Parse the command:
  if command == '' or command == "current" then
    -- Send the message to the channel/query:
    dxirc.Command(mpc_current(), tab_id)
  elseif command == "play" then 
    -- Execute the command:
    mpc_play()
  elseif command == "pause" then 
    -- Execute the command:
    mpc_pause()
  elseif command == "stop" then 
    -- Execute the command:
    mpc_stop()
  elseif command == "prev" then 
    -- Execute the command:
    mpc_prev()
  elseif command == "next" then 
    -- Execute the command:
    mpc_next()
  else
    -- Report invalid command:
    dxirc.Print("mpc: Invalid command `" .. command .. "'", tab_id, '4')
  end
end