#!/usr/bin/env python
# coding=iso-8859-15

import os, hashlib, sys, string, getopt, datetime, time, pipes

SVDRPSEND="svdrpsend"
VERSION="0.0.1"
NAME="cmp_dvd"

MSG_SVDRP=1
MSG_CONSOLE=2
MSG_NONE=0

class progress:
	def __init__(self, max, type, file):
		self.start="%s" % int(time.time())
		self.enabled=True
		self.last_pos=0
		self.pos=0
		self.max_byte=max*2
		self.type=type
		self.file=file
		if type==MSG_SVDRP: self.width = 100
		if type==MSG_CONSOLE: self.width = 80
		if type==MSG_NONE: self.enabled=False
		if type==MSG_CONSOLE: sys.stderr.write("--------------------------------------------------------------------------------\n")
		if type==MSG_SVDRP: os.system("%s PLUG bgprocess PROCESS %s %s %d %s" % (SVDRPSEND, NAME, self.start, 0, pipes.quote(self.file)))
	def add(self, add):
		if self.enabled:
			self.pos=self.pos+add
			if int((self.pos*self.width)/self.max_byte)!=self.last_pos:
				self.last_pos=int((self.pos*self.width)/self.max_byte)
				if self.type==MSG_CONSOLE: sys.stderr.write("=")
				if self.type==MSG_SVDRP: os.system("%s PLUG bgprocess PROCESS %s %s %d %s" % (SVDRPSEND, NAME, self.start, self.last_pos, pipes.quote(self.file)))
	def done(self):
		if self.enabled:
			if self.type==MSG_CONSOLE: sys.stderr.write("\n")
			if self.type==MSG_SVDRP: os.system("%s PLUG bgprocess PROCESS %s %s %d %s" % (SVDRPSEND, NAME, self.start, 120, pipes.quote(self.file)))

def checksum(size, file):
	try:
		f = open(file)
	except IOError:
		p.done()
		nachricht("Fehler beim öffnen von %s" % (file))
		sys.exit(1)
	m = hashlib.md5()
	z=size
	data_s=0
	while z>0:
		if z >= 2048: re=2048
		else: re=z
		try:
			data=f.read(re)
		except IOError:
			p.done()
			nachricht("Lesefehler bei %s auf Position %d" % (file, f.tell()))
			sys.exit(1)
		p.add(len(data))
		data_s=data_s+len(data)
		m.update(data)
		z=z-re

	f.close()
	return m.hexdigest(), data_s

def nachricht(text):
	if MESSAGES==MSG_SVDRP: os.system("%s MESG %s" % (SVDRPSEND, pipes.quote(string.split(text, "\n")[0])))
	if MESSAGES==MSG_CONSOLE: sys.stderr.write("%s\n" % text)

def usage():
	nachricht("""USAGE: %s [options]
    cmp_dvd - A simple tool to compare a ISO Image with the burned DVD.

    options:
    -s, --source=<source file>: The ISO File
    -t, --target=<target file>: The DVD Device
    -m, --messages=<message mode>:
          - SVDRP  : for svdrpsend Messages
          - CONSOLE: for Console Massages
          - NONE   : no Massages
""" % sys.argv[0])

if __name__ == '__main__':

	SOURCE=""
	TARGET=""
	MESSAGES=MSG_CONSOLE
	DEBUG = False
	HELP=False
	CMD_ERR=False
	CMD_VERSION=False

	try:
		opts, args = getopt.getopt(sys.argv[1:],
		"hs:t:m:dv",
		["help", "source=", "messages=", "debug", "version"]
		)
	except getopt.GetoptError: CMD_ERR=True

	for o, a in opts:
		if o in ("-d", "--debug"):
			DEBUG = True
		elif o in ("-v", "--version"):
			CMD_VERSION=True
		elif o in ("-s", "--source"):
			SOURCE = a
		elif o in ("-t", "--target"):
			TARGET = a
		elif o in ("-m", "--massages"):
			if string.upper(a) == "SVDRP":
				MESSAGES=MSG_SVDRP
			elif string.upper(a) == "CONSOLE":
				MESSAGES=MSG_CONSOLE
			elif string.upper(a) == "NONE":
				MESSAGES=MSG_NONE
			else:
				CMD_ERR=True
		elif o in ("-h", "--help"):
			HELP=True

	if HELP:
		usage()
		sys.exit(0)

	if CMD_VERSION: nachricht("Version %s\n" % VERSION)

	if (SOURCE=="") or (TARGET==""):
		if CMD_VERSION: sys.exit(0)
		else: CMD_ERR=True

	if CMD_ERR:
		usage()
		sys.exit(1)

	nachricht("Vergleiche %s mit %s" % (SOURCE, TARGET))

	SIZE=os.path.getsize(SOURCE)
	if DEBUG: nachricht("Source Size: %d\n" % SIZE)

	p=progress(SIZE, MESSAGES, os.path.basename(SOURCE))
	input_crc, input_size=checksum(SIZE, SOURCE)
	if DEBUG: nachricht("Source: CRC %s; Read: %d\n" % (input_crc, input_size))
	output_crc, output_size=checksum(SIZE, TARGET)
	p.done()
	if DEBUG: nachricht("Target: CRC %s; Read: %d\n" % (output_crc, output_size))

	if (input_size <> SIZE) or (output_size <> SIZE):
		nachricht("DVD Vergleich schlug irgendwie fehl!")
		sys.exit(1)

	if output_crc <> input_crc:
		nachricht("DVD Vergleich wies Fehler auf!")
		sys.exit(1)
	else:
		nachricht("DVD erfolgreich gebrannt :)")
		sys.exit(0)