#!/usr/bin/perl 

eval 'exec /usr/bin/perl  -S $0 ${1+"$@"}'
    if 0; # not running under some shell
# -*- perl -*-
# Copyright 2005 Frank Lichtenheld <frank@lichtenheld.de>
#
#    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.
#
#    You should have received a copy of the GNU General Public License
#    along with this program; if not, write to the Free Software
#    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
#

=head1 NAME

parsechangelog - parse Debian changelogs and output them in other formats

=head1 SYNOPSIS

parsechangelog [options] [changelogfile]

 Options:
    --help, -h                  print usage information
    --version, -V               print version information
    --file, -l <file>           changelog file to parse, defaults
                                to 'debian/changelog'
    -F<changelogformat>         ignored if changelogformat = 'debian'
                                for compatibility with dpkg-dev
    -L<libdir>                  ignored for compatibility with dpkg-dev
    --format <outputformat>     see man page for list of available
                                output formats, defaults to 'dpkg'
                                for compatibility with dpkg-dev
    --since, -s, -v <version>   include all changes later than version
    --until, -u <version>       include all changes earlier than version
    --from, -f <version>        include all changes equal or later
                                than version
    --to, -t <version>          include all changes up to or equal
                                than version
    --count, -c, -n <number>    include <number> entries from the top
                                (or the tail if <number> is lower than 0)
    --offset, -o <number>       change the starting point for --count,
                                counted from the top (or the tail if
                                <number> is lower than 0)
    --all                       include all changes

If neither C<changelogfile> nor C<-l E<lt>fileE<gt>> are specified,
F<debian/changelog> will be used. If two different files are
specified the program will abort.

If the filename is C<-> the program reads the changelog from
standard input.

C<--all> overrides all other range selecting options. C<--count>
overrides all other range selection options except for C<--all>.
The range selecting options can be mixed together, but only one
of C<--since> and C<--from> and one of C<--until> and C<--to> can be
specified at the same time.

The dpkg and rfc822 formats default to showing only the first entry
when no other options are given with while the HTML and XML formats
default to showing all entries.

For a more extensive documentation of the range selecting options and
some (hopefully enlightening) examples see
L<Parse::DebianChangelog/"COMMON OUTPUT OPTIONS">.

=head1 DESCRIPTION

parsechangelog parses Debian changelogs as described in the Debian
policy (version 3.6.2.1 at the time of this writing) and converts
them to other output formats. See section L<"SEE ALSO"> for
locations where to find the full format definition.

The output formats supported are currently:

=over 4

=item dpkg

Format as known from L<dpkg-parsechangelog(1)>. All requested entries
(see L<"SYNOPSIS"> on how to select specific entries) are returned in
the usual Debian control format, merged in one stanza, ready to be used
in a F<.changes> file.

=item rfc822

Similar to the C<dpkg> format, but the requested entries are returned
as one stanza each, i.e. they are not merged. This is probably the format
to use if you want a machine-usable representation of the changelog.

=item xml

Just a simple XML dump of the changelog data. Without any schema or
DTD currently, just some made up XML. The actual format might still
change. Comments and Improvements welcome.

=item html

The changelog is converted to a somewhat nice looking HTML file with
some nice features as a quick-link bar with direct links to every entry.
NOTE: This is not configurable yet and was specifically designed
to be used on L<http://packages.debian.org/>. This is planned to be
changed until version 1.0. The used Parse::DebianChangelog module
already supports configuration, however, this isn't exposed by this
program yet.

=back

=cut

    use strict;
use warnings;

use Getopt::Long qw(:config gnu_getopt auto_help);
use Pod::UsageTrans;
use Locale::gettext;
use POSIX;
use Parse::DebianChangelog;

setlocale(LC_MESSAGES, '');
textdomain('Parse-DebianChangelog');

my ( $since, $until, $from, $to, $all, $count, $offset, $file );
my $default_file = 'debian/changelog';
my $format = 'dpkg';
my %allowed_formats = (
		       dpkg => 1,
		       html => 1,
		       xml => 1,
		       rfc822 => 1,
		       );

sub unsupported {
    my ($opt, $val) = @_;

    $opt ||= '';
    $val ||= '';

    if ($opt eq 'F' and $val ne 'debian') {
	die sprintf( gettext('changelog format %s not supported')."\n",
		     $val );
    }

    if ($opt eq 'L') {
	warn gettext('ignored option -L')."\n";
    }
}

sub set_format {
    my ($opt, $val) = @_;

    unless ($allowed_formats{$val}) {
	die sprintf( gettext('output format %s not supported')."\n",
		     $val );
    }

    $format = $val;
}

sub help {
    pod2usage(-msg => "$0 $Parse::DebianChangelog::VERSION\n".
	      gettext( "Copyright (C) 2005 by Frank Lichtenheld\n" ).
	      gettext( "This is free software; see the GNU General Public ".
		       "Licence version 2 or later for copying conditions. ".
		       "There is NO warranty." )."\n",
	      -textdomain => 'Parse-DebianChangelog-Pod',
	      -exitstatus => 0);
}

sub version {
    print "$0 $Parse::DebianChangelog::VERSION\n";
    exit 0;
}

GetOptions( "file|l=s" => \$file,
	    "since|v=s" => \$since,
	    "until|u=s" => \$until,
	    "from|f=s" => \$from,
	    "to|t=s" => \$to,
	    "count|c|n=i" => \$count,
	    "offset|o=i" => \$offset,
	    "F=s" => \&unsupported,
	    "L=s" => \&unsupported,
	    "help|h" => \&help,
	    "version|V" => \&version,
	    "format=s" => \&set_format,
	    "all|a" => \$all,
	    )
    or pod2usage({
	-exitvalue => 2,
	-textdomain => 'Parse-DebianChangelog-Pod'
	    });

die gettext('too many arguments')."\n" if @ARGV > 1;

if (@ARGV) {
    if ($file && ($file ne $ARGV[0])) {
	die sprintf( gettext('more than one file specified (%s and %s)')."\n",
		     $file, $ARGV[0] );
    }
    $file = $ARGV[0];
}

my $changes = Parse::DebianChangelog->init();

$file ||= $default_file;
if ($file eq '-') {
    my @input = <STDIN>;
    $changes->parse({ instring => join('', @input) })
	or die sprintf( gettext('fatal error occured while parsing %s')."\n",
			'input' );
} else {
    $changes->parse({ infile => $file })
	or die sprintf( gettext('fatal error occured while parsing %s')."\n",
			$file );
}


my @all = $all ? ( all => $all ) : ();

{
    # I know that looks ugly, but at least it is safer than an eval...
    no strict 'refs';
    my $func_name = "Parse::DebianChangelog::${format}_str";
    print &{"$func_name"}( $changes,
			   { since => $since, until => $until,
			     from => $from, to => $to,
			     count => $count, offset => $offset,
			     @all });
}

__END__

=head1 SEE ALSO

Parse::DebianChangelog, the underlying Perl module

Description of the Debian changelog format in the Debian policy:
L<http://www.debian.org/doc/debian-policy/ch-source.html#s-dpkgchangelog>.

=head1 AUTHOR

Frank Lichtenheld, E<lt>frank@lichtenheld.deE<gt>

=head1 COPYRIGHT AND LICENSE

Copyright (C) 2005 by Frank Lichtenheld

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.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA

=cut