#!/usr/local/bin/perl -wTI.
#
# TWiki WikiClone (see wiki.pm for $wikiversion and other info)
#
# Copyright (C) 1999 Peter Thoeny, peter@thoeny.com
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details, published at 
# http://www.gnu.org/copyleft/gpl.html

use CGI;
use CGI::Carp qw/ fatalsToBrowser /;
#use wiki;

use lib ( '.' );
use lib ( '../lib' );
use TWiki;

use HTMLDiff;

$query= new CGI;

print "Content-type: text/html\n\n";
#do "wikicfg.pm";
&main();


sub getRevInfo
{
    my( $rev, $topic, $short ) = @_;

    my( $date, $user ) = &TWiki::Store::getRevisionInfo( $topic, "1.$rev", 1 );
    $user = &TWiki::userToWikiName( $user );
    my $revInfo = &TWiki::getRenderedVersion( "$date - $user" );
    if( $short ) {
        # cut time
        $revInfo =~ s/ \- [0-9]*\:[0-9]*//go;
        # eliminate white space to prevent wrap around in HR table:
        $revInfo =~ s/ /\&nbsp\;/go;
    }

    $revInfo =~ s/\n//go;
    return $revInfo;
}


sub main
{
    my $thePathInfo = $query->path_info(); 
    my $theRemoteUser = $query->remote_user();
    my $theTopic = $query->param('topic');
    my $theUrl = $query->url;

    ( $topic, $webName, $scriptUrlPath ) = 
	&TWiki::initialize( $thePathInfo, $theRemoteUser, $theTopic, $theUrl , $query);

    my $tmpl = "", $text = "", $diff = "";
    my $rev1 = $query->param( "rev1" );
    my $rev2 = $query->param( "rev2" );
    my $maxrev= 1;
    my $i = $maxrev,    $j = $maxrev;
    my $revTitle1 = "", $revTitle2 = "";
    my $revInfo1 = "",  $revInfo2 = "";
    my $isMultipleDiff = 0;

    if( ! &TWiki::Store::webExists( $webName ) ) {
	$tmpl= &TWiki::readTemplate( "noweb" );
	$tmpl = &TWiki::handleCommonTags( $tmpl, $topic );
	print $tmpl;
	return;
    }
#    $tmpl= &TWiki::Store::readTemplate( "yadiff" );
    $tmpl= &TWiki::Store::readTemplate( "rdiff" );
    my( $before, $difftmpl, $after) = split( /%REPEAT%/, $tmpl);

    my $topicExists = &TWiki::Store::topicExists( $webName, $topic );
    if( $topicExists ) {
	$maxrev = &TWiki::Store::getRevisionNumber( $topic );
        $maxrev =~ s/1\.//go;  # cut major
	if( ! $rev1 ) { $rev1 = 0; }
	if( ! $rev2 ) { $rev2 = 0; }
        $rev1 =~ s/1\.//go;  # cut major
        $rev2 =~ s/1\.//go;  # cut major
        if( $rev1 < 1 )       { $rev1 = $maxrev; }
        if( $rev1 > $maxrev ) { $rev1 = $maxrev; }
        if( $rev2 < 1 )       { $rev2 = 1; }
        if( $rev2 > $maxrev ) { $rev2 = $maxrev; }
        $revTitle1 = "r1.$rev1";
        $revInfo1 = getRevInfo( $rev1, $topic );
        if( $rev1 != $rev2 ) {
            $revTitle2 = "r1.$rev2";
            $revInfo2 = getRevInfo( $rev2, $topic );
        }
    } else {
	$rev1 = 1;
	$rev2 = 1;
    }


    # format "before" part
    $before =~ s/%REVTITLE1%/$revTitle1/go;
    $before =~ s/%REVTITLE2%/$revTitle2/go;
    $before = &TWiki::handleCommonTags( $before, $topic );
    $before =~ s|</*nop/*>||goi;   # remove <nop> tags (PTh 06 Nov 2000)
    print $before;

    # do one or more diffs
    $difftmpl = &TWiki::handleCommonTags( $difftmpl, $topic );
    if( $topicExists ) {
        my $r1 = $rev1, $r2 = $rev2, $rInfo = "";
        if( $r1 > $r2 + 1) {
            $r2 = $r1 - 1;
            $isMultipleDiff = 1;
        }
        do {
            $diff = $difftmpl;
            $diff =~ s/%REVTITLE1%/r1\.$r1/go;
            $rInfo = getRevInfo( $r1, $topic, 1 );
            $diff =~ s/%REVINFO1%/$rInfo/go;
# Include NEWDIFF here
            # $text = &TWiki::getRevisionDiff( $topic, "1.$r2", "1.$r1" );
            # $text = renderRevisionDiff( $text, $topic );
            my $fileName = "$TWiki::dataDir/$webName/$topic.txt";
            $fileName =~ s/$TWiki::securityFilter//go;
	    if ($r1 == 1) {  # Make a fake one for the beginning
	      my $now = localtime;
	      my @text = ("--- $fileName\tnone\t1.0\n",
	                  "+++ $fileName\t0000/00/00 00:00:00\t1.1\n",
			  "@@ -0,0 +1,111 @@\n" 
			 );
	      push @text,
	        map {"+$_" } split "\n", TWiki::Store::readTopicVersion($webName, $topic, 1.1);
	      $text = HTMLDiff::rcsdiff($fileName, 1.0, 1.1, 
	        DiffOut => \@text, HTMLEscape => 0);
	    } else {
	      $text = HTMLDiff::rcsdiff($fileName, "1.$r2", "1.$r1", 
	        DiffCommand => "$TWiki::rcsDir/rcsdiff", ShowContext => 0, 
		HTMLEscape => 0 );
	    }
	    $text = TWiki::handleCommonTags( $text, $topic );
# Done with NEWDIFF here
            $diff =~ s/%TEXT%/$text/go;
            $diff =~ s|</*nop/*>||goi;   # remove <nop> tags (PTh 06 Nov 2000)
            print $diff;
            $r1 = $r1 - 1;
            $r2 = $r2 - 1;
            if( $r2 < 1 ) { $r2 = 1; }
        } while( ( $r1 > $rev2 ) || ( $r1 == 1 ) );

    } else {
        $diff = $difftmpl;
        $diff =~ s/%REVTITLE1%/$revTitle1/go;
        $diff =~ s/%REVTITLE2%/$revTitle2/go;
        $diff =~ s/%TEXT%//go;
        $diff =~ s|</*nop/*>||goi;   # remove <nop> tags (PTh 06 Nov 2000)
        print $diff;
    }

    if( $TWiki::doLogTopicRdiff ) {
        # write log entry
        &TWiki::writeDebug( "yadiff", "$webName.$topic", "r1.$rev1 r1.$rev2" );
    }

    # format "after" part
    $i = $maxrev;
    $j = $maxrev;
    my $revisions = "";
    my $breakRev = 0;
    if( ( $TWiki::numberOfRevisions > 0 ) && ( $TWiki::numberOfRevisions < $maxrev ) ) {
        $breakRev = $maxrev - $TWiki::numberOfRevisions + 1;
    }

    while( $i > 0 ) {
        $revisions .= " | <A href=\"$scriptUrlPath/view%SCRIPTSUFFIX%/%WEB%/%TOPIC%?rev=1.$i\">r1.$i</A>";
        if( $i != 1 ) {
            if( $i == $breakRev ) {
                $revisions = "$revisions | <A href=\"$scriptUrlPath/oops%SCRIPTSUFFIX%/%WEB%/%TOPIC%?template=oopsrev&amp;param1=1.$maxrev\">&gt;...</A>";
                $i = 1;

            } else {
                if( ( $i == $rev1 ) && ( !$isMultipleDiff ) ) {
                    $revisions .= " | &gt;";
                } else {
                    $j = $i - 1;
                    $revisions .= " | <A href=\"$scriptUrlPath/yadiff%SCRIPTSUFFIX%/%WEB%/%TOPIC%?rev1=1.$i&amp;rev2=1.$j\">&gt;</A>";
                }
            }
        }
        $i = $i - 1;
    }
    $after =~ s/%REVISIONS%/$revisions/go;
    $after =~ s/%REVTITLE1%/$revTitle1/go;
    $after =~ s/%REVINFO1%/$revInfo1/go;
    $after =~ s/%REVTITLE2%/$revTitle2/go;
    $after =~ s/%REVINFO2%/$revInfo2/go;

    $after = &TWiki::handleCommonTags( $after, $topic );
    $after =~ s|</*nop/*>||goi;   # remove <nop> tags (PTh 06 Nov 2000)

    print $after;
}