#!/usr/bin/python

import sys, re, difflib, os

red_color = green_color = end_color = ""
if 1 or os.isatty (sys.stdout.fileno ()):
	red_color = '\033[41;37;1m'
	green_color = '\033[42;37;1m'
	end_color = '\033[m'

def fancy_diff (l1, l2):

	sep = "|<>@+,="
	r ="(["+sep+"]?)([^"+sep+"]*)"
	ss = [re.findall (r, l) for l in (l1, l2)]
	ss = [reduce ((lambda a,b: a+b), s) for s in ss]
	ss = [[x+"\n" for x in s] for s in ss]
	oo = ["",""]
	st = [0,0]
	for l in difflib.Differ().compare (*ss):
		if l[0] == '?':
			continue
		if l[0] == ' ':
			for i in range(2):
				if st[i]:
					oo[i] += end_color
					st[i] = 0
			oo = [o + l[2:] for o in oo]
			continue
		if l[0] == '-':
			if not st[0]:
				oo[0] += red_color
				st[0] = 1
			oo[0] += l[2:]
			continue
		if l[0] == '+':
			if not st[1]:
				oo[1] += green_color
				st[1] = 1
			oo[1] += l[2:]
	for i in range(2):
		if st[i]:
			oo[i] += end_color
			st[i] = 0
	oo = [o.replace ('\n', '') for o in oo]
	if oo[0] == oo[1]:
		return '  ' + oo[0] + '\n'
	return '-'+oo[0]+'\n'+'+'+oo[1]+'\n'


f1, f2 = (file (f) for f in sys.argv[1:3])

for (l1,l2) in zip (f1, f2):
	if l1 == l2:
		print " " + l1.strip ()
		continue
	l1, l2 = l1.strip (), l2.strip ()

	sys.stdout.writelines (fancy_diff (l1, l2))