#!/usr/bin/perl -w
# 
# ucl - update changelog for subversion projects (perl version)
# 
# Copyright (c) 2005-2010 by Ricardo Mones <ricardo@mones.org>
#
# Permission  is hereby granted, free of  charge, to any  person obtaining a
# copy of this software and associated documentation files (the "Software"),
# to deal in the Software without  restriction, including without limitation
# the  rights to use, copy, modify, merge, publish,  distribute, sublicense,
# and/or sell  copies of the  Software, and to  permit  persons to  whom the
# Software is furnished to do so, subject to the following conditions:
#
# The above  copyright  notice and this  permission notice shall be included
# in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED,  INCLUDING BUT NOT LIMITED TO THE  WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A  PARTICULAR PURPOSE AND  NONINFRINGEMENT. IN NO  EVENT SHALL
# THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY,  WHETHER IN AN  ACTION OF CONTRACT, TORT OR  OTHERWISE, ARISING
# FROM,  OUT OF OR  IN  CONNECTION  WITH  THE SOFTWARE OR  THE USE OR  OTHER
# DEALINGS IN THE SOFTWARE.
#

use strict;

my $PROJECT = "clawsker"; # project name under trunk
my $REPO = "https://svn.mones.org/svn"; # repository base URL
my $CL = './ChangeLog'; # changelog file
my $VF = './VERSION'; # version file
my $SF = '.ucl.status'; # status file
my $PCL = '.ucl.prev'; # previous changelog
my @NOTFORRELEASE = ( "ucl" ); 
my $release = undef;

sub tag_new_release {
  my $relnum = shift;
  $_ = $relnum;
  die "Invalid release version\n" unless (/^\d+\.\d+\.\d+$/);
  my $namevers = "$PROJECT-$relnum";
  my $sourceurl = "$REPO/trunk/$PROJECT";
  my $targeturl = "$REPO/tags/$PROJECT/$namevers";
  my $commitmsg = "'tag release $relnum'";
  qx/svn cp $sourceurl $targeturl -m $commitmsg/;
}

sub tarball_from_release_tag {
  my $relnum = shift;
  $_ = $relnum;
  die "Invalid release version\n" unless (/^\d+\.\d+\.\d+$/);
  my $namevers = "$PROJECT-$relnum";
  my $targeturl = "$REPO/tags/$PROJECT/$namevers";
  qx/svn export $targeturl/;
  foreach my $file (@NOTFORRELEASE) {
    if (-f "$namevers/$file") {
      unlink("$namevers/$file");
    }
  }
  qx/tar czf $namevers.tar.gz $namevers/;
}

sub parse_options {
  if (defined($ARGV[0])) {
    $_ = $ARGV[0];
    if (/-r/) {
      die "Undefined release version\n" unless defined ($ARGV[1]);
      $_ = $ARGV[1];
      die "Invalid release version\n" unless (/^\d+\.\d+\.\d+$/);
      $release = $_;
    }
    elsif (/-t/) {
      die "Undefined release version\n" unless defined ($ARGV[1]);
      &tag_new_release ($ARGV[1]);
      exit 0;
    }
    elsif (/-T/) {
      die "Undefined release version\n" unless defined ($ARGV[1]);
      &tarball_from_release_tag ($ARGV[1]);
      exit 0;
    }
    elsif (/-\?/) {
      my $help = <<'ENDOFHELP'
Description:
    ucl          Update changelog for Subversion repository
Syntax:
    ucl [options]
Where options are:
    -r x.y.z     Update is for release version x.y.z
    -t x.y.z     Tags current trunk as release x.y.z on repository
    -T x.y.z     Makes x.y.z release tarball
ENDOFHELP
      ;
      print $help;
      exit 0;
    }
    else {
      die "Unknown option. Try -? for help\n";
    }
  }
}

sub get_changelog_date {
  my ($sec, $min, $hour, $mday, $mon, $year, $wday) = localtime();
  $year += 1900;
  $mon += 1;
  $hour = ($hour < 10)? "0$hour": "$hour";
  $min = ($min < 10)? "0$min": "$min";
  $mon = ($mon < 10)? "0$mon": "$mon";
  $mday = ($mday < 10)? "0$mday": "$mday";
  return "$year-$mon-$mday $hour:$min";
}

sub main {
  # check we're in the right place
  -e "$CL" or die "Oops, no ChangeLog here\n";
  -e "$VF" or die "Oops, no VERSION here\n";
  &parse_options;
  # parser VERSION file or $release argument
  my ($major, $minor, $micro, $extra) = (undef, undef, undef, undef);
  if (not defined ($release)) { # got number it from version file
    open (VTF, "<$VF");
    $_ = <VTF>;
    chomp;
    close (VTF);
  }
  else {
    $_ = $release;
  }
  if (/^(\d+)\.(\d+)\.(\d+)$/) {
    ($major, $minor, $micro, $extra) = ($1, $2, $3, "");
  }
  if (/^(\d+)\.(\d+)\.(\d+)svn(\d+)$/) {
    ($major, $minor, $micro, $extra) = ($1, $2, $3, $4);
  }
  # update directory to be sure we're at the last rev
  $_ = qx/LANGUAGE=C svn up/;
  my @updateout = split /\\n/;
  # get last revision from repository
  $_ = qx/LANGUAGE=C svn info | grep "Revision"/;
  @_ = split (':');
  my $lastrev = $_[1];
  $lastrev =~ s/\s+//;
  # calculate modifications
  qx/svn status > $SF/;
  my @modifs = ();
  open (STF, "<$SF");
  while (<STF>) {
    chomp;
    if (/^MM?\s+(.*)$/) {
      push (@modifs, "\t* $1");
    }
    if (/^AM?\s+(.*)$/) {
      push (@modifs, "\t* $1\t\t**NEW**");
    }
    if (/^D\s+(.*)$/) {
      push (@modifs, "\t* $1\t\t**REMOVED**");
    }
    if (/^\?\s+(.*)$/) {
      print "Info: not versioned: $1\n";
    }
  }
  close (STF);
  unlink ($SF); # remove the status file
  # save previous changelog
  rename ($CL, $PCL);
  # write new entry header
  open (NCL, ">$CL");
  my $cldate = &get_changelog_date;
  my $cluser = $ENV{USER};
  my $clvers = "$major.$minor.$micro";
  if ($release eq "") {
    if ($extra ne "") {
      $clvers = ($clvers . "svn" . (1 + $lastrev));
    }
  }
  # write new entry modifications
  print NCL "$cldate  $cluser   $clvers\n\n";
  foreach my $modif (@modifs) {
    print NCL "$modif\n";
  }
  print NCL "\n";
  # and previous entries
  open (PCL, "<$PCL");
  while (<PCL>) { print NCL $_; }
  close (PCL);
  close (NCL);
  # and keep a digest for checking
  my $oldmd5 = qx/md5sum $CL | cut -f1 -d" "/;
  # edit changelog
  my $editor = 'vim'; # (defined($ENV{DISPLAY}))? 'gvim -f': 'vim';
  if (defined($ENV{EDITOR})) {
    $editor = $ENV{EDITOR};
  }
  my @editor = ($editor, $CL);
  system (@editor);
  # check for changes
  my $newmd5 = qx/md5sum $CL | cut -f1 -d" "/;
  if ($oldmd5 eq $newmd5) {
    print "Unmodified ChangeLog, discarding changes.\n";
    unlink ($CL);
    rename ($PCL, $CL);
  }
  else {
    unlink ($PCL);
    # update new version after changes
    qx/echo $clvers > $VF/;
  }
}

main;

exit 0;