#!/usr/bin/env python

import os, sys, struct, stat

import difflib

import re

from optparse import OptionParser

from mercurial.bdiff import bdiff, blocks

from mercurial.mdiff import bunidiff

VERSION="0.2"

usage = "usage: %prog [options] file1 file2"

parser = OptionParser(usage=usage)

parser.add_option("-d", "--difflib", action="store_true", default=False)

parser.add_option('-x', '--count', default=1)

parser.add_option('-c', '--context', type="int", default=3)

parser.add_option('-p', '--show-c-function', action="store_true", default=False)

parser.add_option('-w', '--ignore-all-space', action="store_true", 

                  default=False)

(options, args) = parser.parse_args()

if not args:

    parser.print_help()

    sys.exit(1)

# simple utility function to put all the

# files from a directory tree into a dict

def buildlist(names, top):

    tlen = len(top)

    for root, dirs, files in os.walk(top):

        l = root[tlen + 1:]

        for x in files:

            p = os.path.join(root, x)

            st = os.lstat(p)

            if stat.S_ISREG(st.st_mode):

                names[os.path.join(l, x)] = (st.st_dev, st.st_ino)

def diff_files(file1, file2):

    if file1 == None:

        b = file(file2).read().splitlines(1)

        l1 = "--- %s\n" % (file2)

        l2 = "+++ %s\n" % (file2)

        l3 = "@@ -0,0 +1,%d @@\n" % len(b)

        l = [l1, l2, l3] + ["+" + e for e in b]

    elif file2 == None:

        a = file(file1).read().splitlines(1)

        l1 = "--- %s\n" % (file1)

        l2 = "+++ %s\n" % (file1)

        l3 = "@@ -1,%d +0,0 @@\n" % len(a)

        l = [l1, l2, l3] + ["-" + e for e in a]

    else:

        t1 = file(file1).read()

        t2 = file(file2).read()

        l1 = t1.splitlines(1)

        l2 = t2.splitlines(1)

        if options.difflib:

            l = difflib.unified_diff(l1, l2, file1, file2)

        else:

            l = bunidiff(t1, t2, l1, l2, file1, file2, context=options.context,

                     showfunc=options.show_c_function,

                     ignorews=options.ignore_all_space)

    for x in l:

        if x[-1] != '\n':

            x += "\n\ No newline at end of file\n"

        print x,

file1 = args[0]

file2 = args[1]

if os.path.isfile(file1) and os.path.isfile(file2):

    diff_files(file1, file2)

elif os.path.isdir(file1):

    if not os.path.isdir(file2):

        sys.stderr.write("file types don't match\n")

        sys.exit(1)

    d1 = {}

    d2 = {}

    buildlist(d1, file1)

    buildlist(d2, file2)

    keys = d1.keys()

    keys.sort()

    for x in keys:

        if x not in d2:

            f2 = None

        else:

            f2 = os.path.join(file2, x)

            st1 = d1[x]

            st2 = d2[x]

            del d2[x]

            if st1[0] == st2[0] and st1[1] == st2[1]:

                sys.stderr.write("%s is a hard link\n" % x)

                continue

        x = os.path.join(file1, x)

        diff_files(x, f2)

    keys = d2.keys()

    keys.sort()

    for x in keys:

        f1 = None

        x = os.path.join(file2, x)

        diff_files(f1, x)