#!/usr/bin/env python

import commands, sys, os, os.path, random, socket, subprocess
import cPickle, datetime, time
from optparse import OptionParser, Values

VERSION = "1.1"
CACHE_LOCATION = os.path.expanduser('~/.randombg2_filelist_cache')

try:
	import GregDebug
	from SigHandler import HUPInterrupt
	from GregDebug import debug, setDebugLevel, DEBUG_LEVEL_DEBUG, DEBUG_LEVEL_LOW, DEBUG_LEVEL_MEDIUM, DEBUG_LEVEL_HIGH, DEBUG_INCREMENT
	from FileLists import *
except ImportError:
	print >>sys.stderr, "Missing libraries!\nExiting..."
	sys.exit(1)

try:
	from collections import defaultdict
	def magicdict():
		return defaultdict(dict)
except ImportError:
	class magicdict(dict):
		def __getitem__(self, key):
			if not self.has_key(key):
				self[key] = {}
			return dict.__getitem__(self, key)

class RandomBG(object):
	KDE_CONFIG = os.path.expanduser('~/.kde/share/config/kdesktoprc')
	def __init__(self, filelist, backgroundColour='black', permanent=False):
		windowManager = self._determineWindowManager()
		debug('Determined the window manager is "%s"' % windowManager, DEBUG_LEVEL_MEDIUM)
		self.backgroundColour = backgroundColour
		self.permanent = permanent
		self.filelist = filelist

		if windowManager == "WMAKER":
			self._randombg = self._randombgWMAKER
		elif windowManager == "KDE":
			self._randombg = self._randombgKDE
		elif windowManager == "OSX":
			self._randombg = self._randombgOSX
		else:
			raise Exception("Unknown window manager")

	def _determineWindowManager(self):
		"""Searches for a some specified windows within the current X session to see 
		what window manager we are running under"""
		
		debug("Testing for OSX (NonX)", DEBUG_LEVEL_LOW)
		if commands.getstatusoutput("ps ax -o command -c|grep -q WindowServer")[0] == 0:
			return "OSX"
		debug("Testing for KDE", DEBUG_LEVEL_LOW)
		if commands.getstatusoutput("xwininfo -name 'KDE Desktop'")[0] == 0:
			return "KDE"
		debug("Testing for WMaker", DEBUG_LEVEL_LOW)
		if commands.getstatusoutput("xlsclients | grep -qi wmaker")[0] == 0:
			return "WMAKER"
		
		return None

	def _randombgWMAKER(self, file):
		cmd = ["wmsetbg", 
			"-b", self.backgroundColour, # Sets the background colour to be what the user specified
			"-S", # 'Smooth' (WTF?)
			"-e", # Center the image on the screen (only affects when the image in no the in the correct aspect ratio
			"-d", # dither
			"-a"] # scale the image, keeping the aspect ratio
		if self.permanent:
			cmd += ["-u"] # update the wmaker database
		cmd += [file]
		return subprocess.Popen(cmd, stdout=sys.stdout, stderr=sys.stderr, stdin=open('/dev/null', 'r')).wait()
	
	def _randombgOSX(self, file):
		cmd = """osascript -e 'tell application "finder" to set desktop picture to posix file "%s"'""" % file
		debug(cmd, DEBUG_LEVEL_DEBUG)
		return commands.getstatusoutput(cmd)[0]

	def _parseKDEConfig(self, filename = KDE_CONFIG):
		fd = open(filename, 'r')
		result = magicdict()
		section = None
		for line in fd:
			line = line.strip()
			if not line or line.startswith('#'):
				continue

			if line.startswith('[') and line.endswith(']'):
				section = line[1:-1]
				result[section] = {}
				continue
			elif not section:
				raise Exception('Invalid kdesktoprc file')

			unpack = line.split('=', 1)
			if len(unpack) == 2:
				key, val = unpack
			else:
				key, val = unpack[0], None
			result[section][key] = val
			
		fd.close()
		return result

	def _writeKDEConfig(self, config, filename = KDE_CONFIG):
		fd = open(filename, 'w')
		for section, values in config.items():
			print >>fd, '[%s]' % section
			for k, v in values.items():
				if v != None:
					print >>fd, '%s=%s' % (k,v)
				else:
					print >>fd, k
			print >>fd
		fd.close()
	
	def _randombgKDE(self, file):
		kdeconfig = self._parseKDEConfig()
		#kdeconfig['Background Common']['DrawBackgroundPerScreen_0']='true'
		for section in ('Desktop0', 'Desktop0Screen0'):
			kdeconfig[section]['Wallpaper'] = file
			kdeconfig[section]['UseSHM'] = 'true'
			kdeconfig[section]['WallpaperMode'] = 'ScaleAndCrop'
			# Ensure that random mode is disabled...
			if 'MultiWallpaperMode' in kdeconfig[section]:
				del kdeconfig[section]['MultiWallpaperMode']

		self._writeKDEConfig(kdeconfig)

		return subprocess.Popen(['dcop', 'kdesktop', 'KBackgroundIface', 'configure'], 
			   stdout=sys.stdout, stderr=sys.stderr, stdin=open('/dev/null', 'r')).wait()

	def __call__(self):
		self.cycleNext()

	def cycleNext(self):
		file = self.filelist.getNextRandomImage()
		return self._randombg(file)
	
	def cyclePrev(self):
		file = self.filelist.getPrevRandomImage()
		return self._randombg(file)

def buildparser():
	def addfilestolist(optclass, opt, value, parser, fileList):
		fo = open(value)
		for line in fo:
			fileList.list.append(line.strip())
		fo.close()
		fileList.allowAllRandom = False
		
	parser = OptionParser(version="%prog " + VERSION, 
		description = "Picks a random background image",
		usage = "%prog [options] dir [dir2 ...]")
	parser.add_option("-p", "--permanent",
		action="store_true", dest="permanent", default=False,
		help="Make the background permanent. Note: This will cause all machines logged in with this account to simultaneously change background [Default: %default]")
	parser.add_option("-q", "--quiet", "--silent",
		action="count", dest="quiet", default=0,
		help="Make the script quiet (good for running from a shell script)")
	parser.add_option("-v", '-d', "--verbose", "--debug",
		action="count", dest="verbose", default=0,
		help="Make the louder (good for debugging, or those who are curious)")
	parser.add_option("-b", "--background-colour",
		action="store", type="string", dest="background_colour", default="black",
		help="Change the default background colour that is displayed if the image is not in the correct aspect ratio [Default: %default]")
	parser.add_option("--all-random",
		action="store_true", dest="all_random", default=False,
		help="Make sure that all images have been displayed before repeating an image")
	parser.add_option("--folder-random",
		action="store_true", dest="folder_random", default=False,
		help="Give each folder an equal chance of having an image selected from it")
	#parser.add_option("--file-list",
	#	action="callback", callback=addfilestolist, type="string", callback_args=(fileList,),
	#	help="Adds the list of images from the external file")
	parser.add_option("--cycle",
		action="store", type="int", default=0, dest="cycle_time",
		help="Cause the image to cycle every X seconds")
	return parser

def main():
	parser = buildparser()
	useroptions, paths = parser.parse_args(sys.argv[1:])

	setDebugLevel(DEBUG_INCREMENT * (useroptions.quiet - useroptions.verbose))
	debug("Just set GregDebug.DEBUG_LEVEL to %d" % GregDebug.DEBUG_LEVEL, DEBUG_LEVEL_LOW)

	if useroptions.all_random:
		filelist = AllRandomFileList()
	elif useroptions.folder_random:
		filelist = FolderRandomFileList()
	else:
		filelist = RandomFileList()

	for path in paths:
		filelist.doAddPath(path)

	if filelist.attemptCacheLoad(CACHE_LOCATION):
		debug("Loaded cache successfully", DEBUG_LEVEL_LOW)
	else:
		debug("Could not load cache")
		filelist.doScanPaths()
	try:

		if not filelist.hasImages():
			print >>sys.stderr, "No files!"
			parser.print_help()
			sys.exit(1)
		
		ret = None
		debug("Initilizing RandomBG", DEBUG_LEVEL_DEBUG)
		randombg = RandomBG(filelist, useroptions.background_colour, useroptions.permanent)
		if useroptions.cycle_time > 0:
			while True:
				try:
					debug("Cycling wallpaper", DEBUG_LEVEL_LOW)
					ret = randombg()
					if ret:
						debug('Could not set wallpaper. Returned "%s" % ret')
						break
					debug('About to sleep for "%d" seconds' % useroptions.cycle_time, DEBUG_LEVEL_LOW)
					time.sleep(useroptions.cycle_time)
				except KeyboardInterrupt, e:
					break
					debug("Caught KeyboardInterrupt", DEBUG_LEVEL_LOW)
				except HUPInterrupt, e:
					# Force a new image to be displayed before the timeout
					debug("Caught SIGHUP: Loading new image")
		else:
			ret = randombg()
		
	finally:
		filelist.doStoreCache(CACHE_LOCATION)
	
	sys.exit(ret)

if __name__ == "__main__":
	main()