#!/usr/bin/env python

import urllib, urllib2, re, os, sys
from urlparse import urlparse

def help():
	print """
$ vc [URL] [OPTIONS]

VC is a Version Control application.

	VC reads the version number from a text file in a website 
	and checks it against the local version number. If your files are
	outdated, it patches them with ones downloaded from the server.
	
	The URL has to include the full path to the file. For example,
	this would be a valid URL:
	
		http://www.domain.com/directory/versions.txt
	
	'-v' makes vc verbose. In verbose mode, the output of all subprocesses
	are piped to you. Verbose mode is off my default."""
	sys.exit()
	
def get_text(url):
	request = urllib2.Request(url)
	return urllib2.urlopen(request).read()

def get_version_numbers(text):
	versions = []
	raw_versions = re.compile('\w\d+[.]\d+').findall(text)
	for x in raw_versions:
		if "a" or "b" or "c" in raw_versions:
			versions.append(x)
		else:
			print "Warning: non-matching version numbers in remote text file\n"
	if len(versions) == 3:
		versions.sort()
		version_result = """These are the latest version numbers:
	Program: %s
	Code: %s
	Graphics: %s\n""" % (versions[0], versions[1], versions[2])
		print version_result
	else:
		sys.stderr.write("Could not find version numbers in text file.\n")
		sys.exit()
	return versions

def get_file_urls(text):
	raw_files = re.compile('http://[.a-z~\-\/]+').findall(text)
	files = []
	for x in raw_files:
		if "program" in x:
			program_file = "A" + x
			files.append(x)
		elif "code" in x:
			code_file = "B" + x
			files.append(x)
		elif "graphics" in x:
			graphics_file = "C" + x
			files.append(x)
		else:
			print "Warning: non-matching file URL found in remote text file.\n"
	if len(files) == 3:
		files.sort()
	else:
		sys.stderr.write("Could not find file URLs in text file.\n")
		sys.exit()
	return files

def parse_numbers(version):
	version = version[1:]
	return version

def get_files(url):
	if verbose == True:
		down_command = "wget %s" % url
	else:
		down_command = "wget -q %s" % url
	os.popen(down_command)

def get_local_version_numbers():
	try:
		local_file = open("vc.txt", "r")
	except:
		sys.stderr.write("Could not find local version file (vc.txt)\n")
		sys.exit()
	file_lines = local_file.readlines()
	local_versions = "".join(file_lines)
	local_file.close()
	local_versions = local_versions.split()
	local_versions.sort()
	if len(local_versions) < 3:
		sys.stderr.write("Could not find enough version numbers in local version file (vc.txt)\n")
		sys.exit()
	else:
		local_program_version = local_versions[0]
		local_code_version = local_versions[1]
		local_graphics_version = local_versions[2]
		return local_versions

def update(local, remote):
	components = ["program is", "code is", "graphics are"]
	for x in range(len(local)):
		local_number = (local[x])
		remote_number = (remote[x])
		if local_number < remote_number:
			print "The %s outdated. Getting files now." % components[x]
			url_temp = get_file_urls(text)[x]
			try:
				get_files(url_temp)
			except:
				sys.stderr.write("Unexpected error while downloading file")
				sys.exit()
			try:
				decompress(get_filename(get_file_urls(x)))
			except:
				sys.stderr.write("Unexpected error while decompressing file")
				sys.exit()
		else:
			print "The %s up to date. Checking next component." % components[x]

def decompress(file):
	if file[-6:] != "tar.gz":
		sys.stderr.write("Downloaded file is not compatible")
		sys.exit()
	else:
		if verbose == True:
			decom_command = "tar -xzv %s" % file
		else:
			decom_command = "tar -xz %s" % file
		os.popen(decom_command)	

def get_filename(url)
	url = urlparse(url)
	url = list(url)
	file = url[2].split("/")
	file = file[-1]

verbose = False
if len(sys.argv) < 2:
	help()
else:
	url = sys.argv[1]
	if url.count("://") == 0:
		url = "http://" + url
	if sys.argv < 3 and sys.argv[2] == "-v":
		verbose = True

text = get_text(url)
update(get_local_version_numbers(), get_version_numbers(text))