#!/usr/bin/perl
use strict;
use Cwd;
use File::Find;

my $changefrom;
while ($changefrom eq '') {
	print "Change (Pattern): ";
	$changefrom = <>;
	chomp($changefrom);
}

print "To... (Pattern): ";
my $changeto = <>;
chomp($changeto);

print "Match files [.]: ";
my $match_files = <>;
chomp($match_files);
$match_files = '.' if ($match_files eq '');

my $cwd = cwd();
print "Directory [$cwd]: ";
my $startdir = <>;
chomp($startdir);
$startdir = $cwd if ($startdir eq '');

print "Case Sens (y/n) [n]: ";
my $case = <>;
chomp($case);

my $change_files_count = 0;
my $change_times_count = 0;
print "Starting search & changes...\n";
&find(\&wanted, $cwd);

if ($change_files_count == 0) {
	print "Done! Didn't find any files to change.\n";
} else {
	print "Done! Made $change_times_count changes ",
		"in $change_files_count files.\n";
}

if (($^O =~ /MS/i) && ($^O =~ /Win/i)) {
	print "\nPress return to exit. ";
	my $ending = <>;
}

exit;

sub wanted {
	if ((-f) && ($_ =~ /$match_files/)) {
		open(DEFILE, $_) || print "Can't open file: $!\n";
		my @file_contents = <DEFILE>;
		close(DEFILE);

		my $happens;
		if (($case eq "y") || ($case eq "Y")) {
			$happens = grep(/$changefrom/, @file_contents);
		} else {
			$happens = grep(/$changefrom/i, @file_contents);
		}

		if ($happens > 0) {
			print "Changing \"$File::Find::name\" file...\n";
			my $file_contents = join('', @file_contents);

			if (($case eq "y") || ($case eq "Y")) {
				$file_contents =~ s/$changefrom/$changeto/g;
			} else {
				$file_contents =~ s/$changefrom/$changeto/gi;
			}

			open(DAFILE, "> $_") || print "Can't write to file: $!\n";
			print DAFILE $file_contents;
			close(DAFILE);

			$change_times_count += $happens;
			$change_files_count++;
		}
	}
}