#!/usr/bin/python
############### 
# cmpcss 
#  Compress a CSS file in prepration for production use. 
#   
# AUTHOR 
#	Michael Crute (mcrute@gmail.com)
# DATE 
#	16 June 2006
# VERSION 
#	1.0 
# PURPOSE 
#	An implementation of a CSS compressor in Python. Written to 
#	prepare development CSS to production ready CSS. Does the
#	following:
#		* Removes spaces intelligently
#		* Removes charset declarations
#		* Removes extra semicolons
#		* Flattens the file (tabs and line breaks)
# USAGE 
# 	cmpcss site_dev.css > site_prod.css
# LICENSE 
#	You may copy and redistribute this program as you see fit, with no 
#	restrictions.  
# WARRANTY 
#	This program comes with NO warranty, real or implied. If it eats
#	your CSS, it's not my problem, you should have kept a backup.
###############

import sys
import re
#import string

# The chewy caramel center of the program
# Don't bitch about the short variable names, it makes it easy to read
def cleanline(theLine):
	# Kills line breaks, tabs, and double spaces
	p = re.compile('(\n|\r|\t|\f|\v)+')
	m = p.sub('',theLine)

	# Kills double spaces
	p = re.compile('(  )+')
	m = p.sub(' ',m)

	# Removes last semicolon before }
	p = re.compile('(; }|;})+')
	m = p.sub('}',m)

	# Removes space before {
	p = re.compile('({ )+')
	m = p.sub('{',m)

	# Removes all comments
	p = re.compile('/\*([^*]|[\r\n]|(\*+([^*/]|[\r\n])))*\*+/')
	m = p.sub('',m)

	# Strip off the Charset
	p = re.compile('@CHARSET .*;')
	m = p.sub('',m)

	# Strip spaces before the {
	p = re.compile(' {')
	m = p.sub('{',m)

	# Strip space after :
	p = re.compile(': ')
	m = p.sub(':',m)

	# Strip space after ,
	p = re.compile(', ')
	m = p.sub(',',m)

	# Strip space after ;
	p = re.compile('; ')
	m = p.sub(';',m)

# May return to add color code compression
# not a huge space saver so also not high priority
#	p = re.compile('.*#[0-9A-F]{6}.*')
#	cc = p.match(m)
	
#	if cc:
#		cc = compcolor(m)

	return m

#def compcolor(m):

# Boring usage info for people too dumb to use the program
def printusage():
	print ''
	print 'SoftGroup CSS Compressor'
	print ''
	print 'This is a compressor for CSS files.'
	print 'As far as I know it doesn\'t break the standards'
	print 'compliance of the file. If you can find a way'
	print 'to make it break a file please email me.'
	print ''
	print 'Usage: cmpcss <filename>'
	sys.exit()

# The main routine
if ( __name__ == "__main__" ):
	if (len(sys.argv) <= 1):
		printusage()

	# Open the file for reading
	try: 
		theFile = file(sys.argv[1], "r")
	except IOError:
		print 'I couldn\'t open your file.'
		sys.exit()
	
	# Initialize temp so it's not scoped to the for loop
	temp = ''
	
	# Loop through the file line by line and clean it
	for line in theFile:
		temp = temp + cleanline(line)

	# Once more, clean the entire file string
	print cleanline(temp)

	# Cleanup after ourselves
	theFile.close()