path: root/localworddiff

#!/usr/bin/perl
#
# Copyright © 2013 Jonas Smedegaard <dr@jones.dk>
# Description: Generate word-based diff for console or web
#
# 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 3, 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.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#
# Depends: libtext-markdown-perl libhtml-html5-builder libcss-perl
# Depends: libtext-worddiff-perl (>= 0.08)

use Text::WordDiff;
use Text::Markdown qw[markdown];
use CSS::Tiny;
use HTML::HTML5::Builder qw[:standard];;
use File::Slurp;

use strictures 1;
use autodie;

my ($infile1, $infile2, $outfile) = @ARGV;

die 'Missing input file arguments'
    unless ($infile1 and $infile2);

# use console if no output file provided as third argument
unless ($outfile) {
    print word_diff $infile1, $infile2, { STYLE => 'ANSIColor' };
    exit 0;
}

# resolve diff
my $diff = word_diff $infile1, $infile2, { STYLE => 'HTMLTwoLines' };

# apply markup to each file div of resolved diff
my $d = "<div class=\"file\">";
my $d_ = "<\/div>";
my $i;
my @diffchunk;
foreach ( split /(?:$d_\n)?$d/, $diff ) {
    if ($_) {
        $diffchunk[$i++] = $d.markdown($_).$d_;
    }
}

# parse styling
my $css = CSS::Tiny->new();
$css->read_string (<<'EOF');
.fileheader {
    display: none;
    visibility: hidden;
}
.file {
    float: left;
    width: 49%;
}
.file .hunk del,
.file .hunk ins {
    font-weight: bold;
    text-decoration: inherit;
}
.file .hunk del {
    color: darkred;
}
.file .hunk ins {
    color: darkgreen;
}
EOF

# compose and save web page
my $page = html(
    head(
        XML_CHUNK($css->html),
    ),
    body(
        CHUNK($diffchunk[0]),
        CHUNK($diffchunk[1]),
    ),
);
write_file( $outfile, $page );

1;