#!/usr/bin/env python
import pygtk
import gtk
import gobject
import commands
import sys
import os
import re
import getopt

def err(msg):
  print msg
  sys.exit(1)

def usage():
  print '''
Usage: changevol [options] [argument]

Options:
  -i, --increase  increase volume by `argument'
  -d, --decrease  decrease volume by `argument'
  -c, --control   specify the mixer control by `argument' (default Master)
                  use only to modify a mixer other than Master

  -t, --toggle    toggle mute on and off
  -s, --status    display current volume status without modifying it
  -q, --quiet     don't display the gtk progressbar, just change the volume
  -b, --backlight adjust the backlight using xbacklight
  -h, --help      display this help message

Note:
  Volume increases and decreases won't be exact due to amixer oddities.
'''
  sys.exit(0)

class GetVolInfo:

  def __init__(self, command):
    self.amixeroutput = commands.getoutput(command)

    if re.compile("off]$", re.M).search(self.amixeroutput, 1):
      self.realvol = "0"
      self.endlabel = "Mute"
    else:
      self.tempvolarray1 = self.amixeroutput.split("[")
      self.tempvolarray2 = self.tempvolarray1[1].split("%")
      self.realvol = self.tempvolarray2[0]
      self.endlabel = self.realvol + " %"

    self.percent = float(self.realvol)/100
    self.label = "Volume " + self.endlabel

class ProgressBar:
  
  def timeout_callback(self):
    gtk.main_quit()
    return False

  def __init__(self, fraction, label):
    self.window = gtk.Window(gtk.WINDOW_POPUP)
    self.window.set_border_width(0)
    self.window.set_default_size(180, -1)
    self.window.set_position(gtk.WIN_POS_CENTER)

    timer = gobject.timeout_add(1000, self.timeout_callback)

    self.bar = gtk.ProgressBar()
    self.bar.set_fraction(fraction)
    self.bar.set_orientation(gtk.PROGRESS_LEFT_TO_RIGHT)
    self.bar.set_text(label)
    self.bar.show()

    self.window.add(self.bar)
    self.window.show()


#Run through parameters, set variables and such
CONTROL = "Master"
AMIXEROPTION = "unset"
QUIET = "NO"
BACKLIGHT = "NO"

if (len(sys.argv) < 2):
  usage()

try:
  opts, args = getopt.getopt(sys.argv[1:], "bqhtsc:i:d:", ["backlight" "quiet", "help", "toggle", "status", "control=", "increase=", "decrease="])
except getopt.GetoptError:
  err("Incorrect usage, see changevol --help.")

if (len(opts) == 0):
  err("Incorrect usage, see --help.")

for opt, arg in opts:
  if opt in ("-h", "--help"):
    usage()
  elif opt in ("-q", "--quiet"):
    QUIET = "YES"
  elif opt in ("-b", "--backlight"):
    BACKLIGHT = "YES"
  elif opt in ("-t", "--toggle"):
    AMIXEROPTION = "toggle"
  elif opt in ("-s", "--status"):
    INCREMENT = "0"
    AMIXEROPTION = INCREMENT + "%+"
  elif opt in ("-c", "--control"):
    CONTROL = arg
  elif opt in ("-i", "--increase"):
    INCREMENT = arg
    AMIXEROPTION = INCREMENT + "%+"
  elif opt in ("-d", "--decrease"):
    INCREMENT = arg
    AMIXEROPTION = INCREMENT + "%-"
  else:
    err("Incorrect usage, see --help")

if (AMIXEROPTION == "unset"):
  err("No volume changing action has been dictated. See changevol --help.")

command = "amixer set " + CONTROL + " " + AMIXEROPTION

#Execution
volume = GetVolInfo(command)
if (QUIET == "NO"):
  ProgressBar(volume.percent, volume.label)
  gtk.main()

if (BACKLIGHT == "YES"):
  os.execv('/usr/bin/xbacklight', ['placeholder', '-set', volume.realvol])