#!/usr/bin/perl

use strict;
use warnings 'all';
use locale;

use FindBin;
use Getopt::Std;


my %opts;
getopts('hir', \%opts);

&usage if $opts{h};
&usage unless $#ARGV==1;

my @revs = grep {$_} map {/^r(\d+)/; $1} `svn log -q $ARGV[0]`;
@revs = reverse @revs unless $opts{r};
exit unless @revs;

$|=1;
for my $r (0..$#revs-1) {
	my @out = map {
		"$revs[$r]:$revs[$r+1] : $_"
	} `svn di -r$revs[$r]:$revs[$r+1] $ARGV[0] | egrep '^[\+\-]' | egrep -v [\+\-]{3}`;
	if ($opts{i}) {
		@out = grep {/$ARGV[1]/i} @out;
	} else {
		@out = grep {/$ARGV[1]/} @out;
	}
	print join '', @out;
}


sub usage {
	print <<EOM;
Usage: 
    $FindBin::RealScript [options] {file|URL} pattern

Options:
    -h    Print this help message
    -i    Ignore case
    -r    Reverse search
EOM
	exit;
}