# Copyright © 2008 Raphaël Hertzog <hertzog@debian.org>
#
# 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, see <http://www.gnu.org/licenses/>.

package Dpkg::Source::Package::V2;

use strict;
use warnings;

use base 'Dpkg::Source::Package';

use Dpkg;
use Dpkg::Gettext;
use Dpkg::ErrorHandling;
use Dpkg::Compression;
use Dpkg::Source::Archive;
use Dpkg::Source::Patch;
use Dpkg::Exit;
use Dpkg::Source::Functions qw(erasedir is_binary);

use POSIX;
use File::Basename;
use File::Temp qw(tempfile tempdir);
use File::Path;
use File::Spec;
use File::Find;

our $CURRENT_MINOR_VERSION = "0";

sub init_options {
    my ($self) = @_;
    $self->SUPER::init_options();
    $self->{'options'}{'include_removal'} = 0
        unless exists $self->{'options'}{'include_removal'};
    $self->{'options'}{'include_timestamp'} = 0
        unless exists $self->{'options'}{'include_timestamp'};
    $self->{'options'}{'include_binaries'} = 0
        unless exists $self->{'options'}{'include_binaries'};
    $self->{'options'}{'preparation'} = 1
        unless exists $self->{'options'}{'preparation'};
    $self->{'options'}{'skip_patches'} = 0
        unless exists $self->{'options'}{'skip_patches'};
    $self->{'options'}{'skip_debianization'} = 0
        unless exists $self->{'options'}{'skip_debianization'};
}

sub parse_cmdline_option {
    my ($self, $opt) = @_;
    if ($opt =~ /^--include-removal$/) {
        $self->{'options'}{'include_removal'} = 1;
        return 1;
    } elsif ($opt =~ /^--include-timestamp$/) {
        $self->{'options'}{'include_timestamp'} = 1;
        return 1;
    } elsif ($opt =~ /^--include-binaries$/) {
        $self->{'options'}{'include_binaries'} = 1;
        return 1;
    } elsif ($opt =~ /^--no-preparation$/) {
        $self->{'options'}{'preparation'} = 0;
        return 1;
    } elsif ($opt =~ /^--skip-patches$/) {
        $self->{'options'}{'skip_patches'} = 1;
        return 1;
    } elsif ($opt =~ /^--skip-debianization$/) {
        $self->{'options'}{'skip_debianization'} = 1;
        return 1;
    }
    return 0;
}

sub do_extract {
    my ($self, $newdirectory) = @_;
    my $fields = $self->{'fields'};

    my $dscdir = $self->{'basedir'};

    my $basename = $self->get_basename();
    my $basenamerev = $self->get_basename(1);

    my ($tarfile, $debianfile, %origtar, %seen);
    foreach my $file ($self->get_files()) {
        (my $uncompressed = $file) =~ s/\.$comp_regex$//;
        error(_g("duplicate files in %s source package: %s.*"), "v2.0",
              $uncompressed) if $seen{$uncompressed};
        $seen{$uncompressed} = 1;
        if ($file =~ /^\Q$basename\E\.orig\.tar\.$comp_regex$/) {
            $tarfile = $file;
        } elsif ($file =~ /^\Q$basename\E\.orig-([\w-]+)\.tar\.$comp_regex$/) {
            $origtar{$1} = $file;
        } elsif ($file =~ /^\Q$basenamerev\E\.debian\.tar\.$comp_regex$/) {
            $debianfile = $file;
        } else {
            error(_g("unrecognized file for a %s source package: %s"),
            "v2.0", $file);
        }
    }

    unless ($tarfile and $debianfile) {
        error(_g("missing orig.tar or debian.tar file in v2.0 source package"));
    }

    erasedir($newdirectory);

    # Extract main tarball
    info(_g("unpacking %s"), $tarfile);
    my $tar = Dpkg::Source::Archive->new(filename => "$dscdir$tarfile");
    $tar->extract($newdirectory, no_fixperms => 1);

    # Extract additional orig tarballs
    foreach my $subdir (keys %origtar) {
        my $file = $origtar{$subdir};
        info(_g("unpacking %s"), $file);
        if (-e "$newdirectory/$subdir") {
            warning(_g("required removal of `%s' installed by original tarball"), $subdir);
            erasedir("$newdirectory/$subdir");
        }
        $tar = Dpkg::Source::Archive->new(filename => "$dscdir$file");
        $tar->extract("$newdirectory/$subdir", no_fixperms => 1);
    }

    # Stop here if debianization is not wanted
    return if $self->{'options'}{'skip_debianization'};

    # Extract debian tarball after removing the debian directory
    info(_g("unpacking %s"), $debianfile);
    erasedir("$newdirectory/debian");
    # Exclude existing symlinks from extraction of debian.tar.gz as we
    # don't want to overwrite something outside of $newdirectory due to a
    # symlink
    my @exclude_symlinks;
    my $wanted = sub {
        return if not -l $_;
        my $fn = File::Spec->abs2rel($_, $newdirectory);
        push @exclude_symlinks, "--exclude", $fn;
    };
    find({ wanted => $wanted, no_chdir => 1 }, $newdirectory);
    $tar = Dpkg::Source::Archive->new(filename => "$dscdir$debianfile");
    $tar->extract($newdirectory, in_place => 1,
                  options => [ '--anchored', '--no-wildcards',
                  @exclude_symlinks ]);

    # Apply patches (in a separate method as it might be overriden)
    $self->apply_patches($newdirectory) unless $self->{'options'}{'skip_patches'};
}

sub get_autopatch_name {
    return "zz_debian-diff-auto";
}

sub get_patches {
    my ($self, $dir, $skip_auto) = @_;
    my @patches;
    my $pd = "$dir/debian/patches";
    my $auto_patch = $self->get_autopatch_name();
    if (-d $pd) {
        opendir(DIR, $pd) || syserr(_g("cannot opendir %s"), $pd);
        foreach my $patch (sort readdir(DIR)) {
            # patches match same rules as run-parts
            next unless $patch =~ /^[\w-]+$/ and -f "$pd/$patch";
            next if $skip_auto and $patch eq $auto_patch;
            push @patches, $patch;
        }
        closedir(DIR);
    }
    return @patches;
}

sub apply_patches {
    my ($self, $dir, $skip_auto) = @_;
    my @patches = $self->get_patches($dir, $skip_auto);
    return unless scalar(@patches);
    my $timestamp = time();
    my $applied = File::Spec->catfile($dir, "debian", "patches", ".dpkg-source-applied");
    open(APPLIED, '>', $applied) || syserr(_g("cannot write %s"), $applied);
    foreach my $patch ($self->get_patches($dir, $skip_auto)) {
        my $path = File::Spec->catfile($dir, "debian", "patches", $patch);
        info(_g("applying %s"), $patch) unless $skip_auto;
        my $patch_obj = Dpkg::Source::Patch->new(filename => $path);
        $patch_obj->apply($dir, force_timestamp => 1,
                          timestamp => $timestamp,
                          add_options => [ '-E' ]);
        print APPLIED "$patch\n";
    }
    close(APPLIED);
}

sub can_build {
    my ($self, $dir) = @_;
    foreach ($self->find_original_tarballs()) {
        return 1 if /\.orig\.tar\.$comp_regex$/;
    }
    return (0, _g("no orig.tar file found"));
}

sub prepare_build {
    my ($self, $dir) = @_;
    $self->{'diff_options'} = {
        diff_ignore_regexp => $self->{'options'}{'diff_ignore_regexp'},
        include_removal => $self->{'options'}{'include_removal'},
        include_timestamp => $self->{'options'}{'include_timestamp'},
        use_dev_null => 1,
    };
    push @{$self->{'options'}{'tar_ignore'}}, "debian/patches/.dpkg-source-applied";
    $self->check_patches_applied($dir) if $self->{'options'}{'preparation'};
}

sub check_patches_applied {
    my ($self, $dir) = @_;
    my $applied = File::Spec->catfile($dir, "debian", "patches", ".dpkg-source-applied");
    unless (-e $applied) {
        warning(_g("patches have not been applied, applying them now (use --no-preparation to override)"));
        $self->apply_patches($dir);
    }
}

sub do_build {
    my ($self, $dir) = @_;
    my ($dirname, $updir) = fileparse($dir);
    my @argv = @{$self->{'options'}{'ARGV'}};
    if (scalar(@argv)) {
        usageerr(_g("-b takes only one parameter with format `%s'"),
                 $self->{'fields'}{'Format'});
    }
    $self->prepare_build($dir);

    my $include_binaries = $self->{'options'}{'include_binaries'};
    my @tar_ignore = map { "--exclude=$_" } @{$self->{'options'}{'tar_ignore'}};

    my $sourcepackage = $self->{'fields'}{'Source'};
    my $basenamerev = $self->get_basename(1);
    my $basename = $self->get_basename();
    my $basedirname = $basename;
    $basedirname =~ s/_/-/;

    # Identify original tarballs
    my ($tarfile, %origtar);
    my @origtarballs;
    foreach (sort $self->find_original_tarballs()) {
        if (/\.orig\.tar\.$comp_regex$/) {
            $tarfile = $_;
            push @origtarballs, $_;
            $self->add_file($_);
        } elsif (/\.orig-([\w-]+)\.tar\.$comp_regex$/) {
            $origtar{$1} = $_;
            push @origtarballs, $_;
            $self->add_file($_);
        }
    }

    error(_g("no orig.tar file found")) unless $tarfile;

    info(_g("building %s using existing %s"),
	 $sourcepackage, "@origtarballs");

    # Unpack a second copy for comparison
    my $tmp = tempdir("$dirname.orig.XXXXXX", DIR => $updir);
    push @Dpkg::Exit::handlers, sub { erasedir($tmp) };

    # Extract main tarball
    my $tar = Dpkg::Source::Archive->new(filename => $tarfile);
    $tar->extract($tmp);

    # Extract additional orig tarballs
    foreach my $subdir (keys %origtar) {
        my $file = $origtar{$subdir};
        $tar = Dpkg::Source::Archive->new(filename => $file);
        $tar->extract("$tmp/$subdir");
    }

    # Copy over the debian directory
    system("cp", "-a", "--", "$dir/debian", "$tmp/");
    subprocerr(_g("copy of the debian directory")) if $?;

    # Apply all patches except the last automatic one
    $self->apply_patches($tmp, 1);

    # Prepare handling of binary files
    my %auth_bin_files;
    my $incbin_file = File::Spec->catfile($dir, "debian", "source", "include-binaries");
    if (-f $incbin_file) {
        open(INC, "<", $incbin_file) || syserr(_g("cannot read %s"), $incbin_file);
        while(defined($_ = <INC>)) {
            chomp; s/^\s*//; s/\s*$//;
            next if /^#/ or /^$/;
            $auth_bin_files{$_} = 1;
        }
        close(INC);
    }
    my @binary_files;
    my $handle_binary = sub {
        my ($self, $old, $new) = @_;
        my $relfn = File::Spec->abs2rel($new, $dir);
        # Include binaries if they are whitelisted or if
        # --include-binaries has been given
        if ($include_binaries or $auth_bin_files{$relfn}) {
            push @binary_files, $relfn;
        } else {
            errormsg(_g("cannot represent change to %s: %s"), $new,
                     _g("binary file contents changed"));
            errormsg(_g("add %s in debian/source/include-binaries if you want" .
                     " to store the modified binary in the debian tarball"),
                     $relfn);
            $self->register_error();
        }
    };
    # Check if the debian directory contains unwanted binary files
    my $unwanted_binaries = 0;
    my $check_binary = sub {
        my $fn = File::Spec->abs2rel($_, $dir);
        if (-f $_ and is_binary($_)) {
            if ($include_binaries or $auth_bin_files{$fn}) {
                push @binary_files, $fn;
            } else {
                errormsg(_g("unwanted binary file: %s"), $fn);
                $unwanted_binaries++;
            }
        }
    };
    my $tar_ignore_glob = "{" . join(",",
        map {
            my $copy = $_;
            $copy =~ s/,/\\,/g;
            $copy;
        } @{$self->{'options'}{'tar_ignore'}}) . "}";
    my $filter_ignore = sub {
        # Filter out files that are not going to be included in the debian
        # tarball due to ignores.
        my %exclude;
        my $reldir = File::Spec->abs2rel($File::Find::dir, $dir);
        foreach my $fn (glob($tar_ignore_glob)) {
            $exclude{$fn} = 1;
        }
        my @result;
        foreach my $fn (@_) {
            unless (exists $exclude{$fn} or exists $exclude{"$reldir/$fn"}) {
                push @result, $fn;
            }
        }
        return @result;
    };
    find({ wanted => $check_binary, preprocess => $filter_ignore,
           no_chdir => 1 }, File::Spec->catdir($dir, "debian"));
    error(_g("detected %d unwanted binary file(s) " .
        "(add them in debian/source/include-binaries to allow their " .
        "inclusion)."), $unwanted_binaries) if $unwanted_binaries;

    # Create a patch
    my $autopatch = File::Spec->catfile($dir, "debian", "patches",
                                        $self->get_autopatch_name());
    my ($difffh, $tmpdiff) = tempfile("$basenamerev.diff.XXXXXX",
                                      DIR => $updir, UNLINK => 0);
    push @Dpkg::Exit::handlers, sub { unlink($tmpdiff) };
    my $diff = Dpkg::Source::Patch->new(filename => $tmpdiff,
                                        compression => "none");
    $diff->create();
    $diff->set_header($self->get_patch_header($dir, $autopatch));
    $diff->add_diff_directory($tmp, $dir, basedirname => $basedirname,
            %{$self->{'diff_options'}}, handle_binary_func => $handle_binary);
    error(_g("unrepresentable changes to source")) if not $diff->finish();
    # The previous auto-patch must be removed, it has not been used and it
    # will be recreated if it's still needed
    if (-e $autopatch) {
        unlink($autopatch) || syserr(_g("cannot remove %s"), $autopatch);
    }
    # Install the diff as the new autopatch
    if (not -s $tmpdiff) {
        unlink($tmpdiff) || syserr(_g("cannot remove %s"), $tmpdiff);
    } else {
        mkpath(File::Spec->catdir($dir, "debian", "patches"));
        info(_g("local changes stored in %s, the modified files are:"), $autopatch);
        my $analysis = $diff->analyze($dir);
        foreach my $fn (sort keys %{$analysis->{'filepatched'}}) {
            print " $fn\n";
        }
        rename($tmpdiff, $autopatch) ||
                syserr(_g("cannot rename %s to %s"), $tmpdiff, $autopatch);
        chmod(0666 & ~ umask(), $autopatch) ||
                syserr(_g("unable to change permission of `%s'"), $autopatch);
    }
    $self->register_autopatch($dir);
    rmdir(File::Spec->catdir($dir, "debian", "patches")); # No check on purpose
    pop @Dpkg::Exit::handlers;

    # Remove the temporary directory
    erasedir($tmp);
    pop @Dpkg::Exit::handlers;

    # Update debian/source/include-binaries if needed
    if (scalar(@binary_files) and $include_binaries) {
        mkpath(File::Spec->catdir($dir, "debian", "source"));
        open(INC, ">>", $incbin_file) || syserr(_g("cannot write %s"), $incbin_file);
        foreach my $binary (@binary_files) {
            unless ($auth_bin_files{$binary}) {
                print INC "$binary\n";
                info(_g("adding %s to %s"), $binary, "debian/source/include-binaries");
            }
        }
        close(INC);
    }
    # Create the debian.tar
    my $debianfile = "$basenamerev.debian.tar." . $self->{'options'}{'comp_ext'};
    info(_g("building %s in %s"), $sourcepackage, $debianfile);
    $tar = Dpkg::Source::Archive->new(filename => $debianfile);
    $tar->create(options => \@tar_ignore, 'chdir' => $dir);
    $tar->add_directory("debian");
    foreach my $binary (@binary_files) {
        $tar->add_file($binary) unless $binary =~ m{^debian/};
    }
    $tar->finish();

    $self->add_file($debianfile);
}

sub get_patch_header {
    my ($self, $dir, $previous) = @_;
    return "Description: Undocumented upstream changes
 This patch has been created by dpkg-source during the package build
 but it might have accumulated changes from several uploads. Please
 check the changelog to (hopefully) learn more on those changes.\n\n";
}

sub register_autopatch {
    my ($self, $dir) = @_;
    my $autopatch = File::Spec->catfile($dir, "debian", "patches",
                                        $self->get_autopatch_name());
    if (-e $autopatch) {
        my $applied = File::Spec->catfile($dir, "debian", "patches", ".dpkg-source-applied");
        open(APPLIED, '>>', $applied) || syserr(_g("cannot write %s"), $applied);
        print APPLIED ($self->get_autopatch_name() . "\n");
        close(APPLIED);
    }
}

# vim:et:sw=4:ts=8
1;