#!/usr/bin/perl

=head1 NAME

dh_gencontrol - generate and install control file

=cut

use strict;
use warnings;
use Debian::Debhelper::Dh_Lib;

our $VERSION = DH_BUILTIN_VERSION;

=head1 SYNOPSIS

B<dh_gencontrol> [S<I<debhelper options>>] [S<B<--> I<params>>]

=head1 DESCRIPTION

B<dh_gencontrol> is a debhelper program that is responsible for generating
control files, and installing them into the I<DEBIAN> directory with the
proper permissions.

This program is merely a wrapper around L<dpkg-gencontrol(1)>, which
calls it once for each package being acted on (plus related dbgsym
packages), and passes in some additional useful flags.

B<Note> that if you use B<dh_gencontrol>, you must also use
L<dh_builddeb(1)> to build the packages.  Otherwise, your build may
fail to build as B<dh_gencontrol> (via L<dpkg-gencontrol(1)>) declares
which packages are built.  As debhelper automatically generates dbgsym
packages, it some times adds additional packages, which will be built
by L<dh_builddeb(1)>.


=head1 OPTIONS

=over 4

=item B<--> I<params>

Pass I<params> to L<dpkg-gencontrol(1)>.

=item B<-u>I<params>, B<--dpkg-gencontrol-params=>I<params>

This is another way to pass I<params> to L<dpkg-gencontrol(1)>.
It is deprecated; use B<--> instead.

=back

=cut

init(options => {
	"dpkg-gencontrol-params=s", => \$dh{U_PARAMS},
});

if (not compat(13)) {
	# Load once early, so each child does not have to load these again (they are expensive
	# compared to Debian::Debhelper::Dh_Lib).
	require Dpkg::Control;
	require Dpkg::Control::Fields;
}

# The `substvars` file ius not quite a pkgfile, but it works similar enough that people might
# be surprised if it was not detected.
# INTROSPECTABLE: CONFIG-FILES pkgfile(substvars)

on_pkgs_in_parallel {
	foreach my $package (@_) {
		my $tmp=tmpdir($package);
		my $ext=pkgext($package);
		my $dbgsym_info_dir = "debian/.debhelper/${package}";
		my $dbgsym_tmp = dbgsym_tmpdir($package);

		my $substvars="debian/${ext}substvars";

		my $changelog = pkgfile(
			{
				'internal-nameless-variant-handling' => 1,
				'named'                              => 0,
				'support-architecture-restriction'   => 0,
			},
			$package,
			'changelog',
		);

		install_dir("$tmp/DEBIAN");

		# avoid gratuitous warnings
		ensure_substvars_are_present($substvars, 'misc:Depends', 'misc:Pre-Depends')
			if compat(13);

		my (@debug_info_params, $build_ids, @pkg_gencontrol_args);
		if ( -d $dbgsym_info_dir ) {
			$build_ids = read_dbgsym_build_ids($dbgsym_info_dir);
		}
		my $has_dbgsym = -d $dbgsym_tmp;

		my ($dctrl, $added_dbgsym_version);
		($dctrl, $added_dbgsym_version) = Debian::Debhelper::Dh_Lib::dh_gencontrol_automatic_substvars($package, $substvars, $has_dbgsym)
			if not compat(13);
		$dctrl //= 'debian/control';


		if ($has_dbgsym) {
			my $dbgsym_package = $added_dbgsym_version ? "${package}-dbgsym" : $package;
			my $dbgsym_ctrl = $added_dbgsym_version ? $dctrl : 'debian/control';
			my $dbgsym_substvar = $added_dbgsym_version ? '/dev/null' : $substvars;
			my $multiarch = package_multiarch($package);
			my $section = package_section($package);
			my $replaces = read_dbgsym_migration($dbgsym_info_dir);
			my $component = '';
			if ($section =~ m{^(.*)/[^/]+$}) {
				$component = "${1}/";
				# This should not happen, but lets not propagate the error
				# if does.
				$component = '' if $component eq 'main/';
			}

			# Remove and override more or less every standard field.
			my @dbgsym_options = (qw(
					-UPre-Depends -URecommends -USuggests -UEnhances -UProvides -UEssential
						-UConflicts -DPriority=optional -UHomepage -UImportant
						-DAuto-Built-Package=debug-symbols
						-UProtected -UBuilt-Using -UStatic-Built-Using
					),
				"-DPackage=${package}-dbgsym",
				"-DDepends=${package} (= \${binary:Version})",
				"-DDescription=debug symbols for ${package}",
				"-DBuild-Ids=${build_ids}",
				"-DSection=${component}debug",
			);
			push(@dbgsym_options, "-DPackage-Type=${\DBGSYM_PACKAGE_TYPE}")
				if DBGSYM_PACKAGE_TYPE ne DEFAULT_PACKAGE_TYPE;
			# Disable multi-arch unless the original package is an
			# multi-arch: same package.  In all other cases, we do not
			# need a multi-arch value.
			if ($multiarch ne 'same') {
				push(@dbgsym_options, '-UMulti-Arch');
			} else {
				push(@dbgsym_options, "-DMulti-Arch=$multiarch");
			}
			# If the dbgsym package is replacing an existing -dbg package,
			# then declare the necessary Breaks + Replaces.  Otherwise,
			# clear the fields.
			if ($replaces) {
				push(@dbgsym_options, "-DReplaces=${replaces}",
					"-DBreaks=${replaces}");
			} else {
				push(@dbgsym_options, '-UReplaces', '-UBreaks');
			}
			install_dir("${dbgsym_tmp}/DEBIAN");
			eval {
				doit("dpkg-gencontrol", "-p${dbgsym_package}", "-l$changelog", "-T${dbgsym_substvar}",
					"-c${dbgsym_ctrl}", "-P${dbgsym_tmp}", @{$dh{U_PARAMS}}, @dbgsym_options);
			};
			if (my $err = "$@") {
				if ($dbgsym_ctrl ne 'debian/control') {
					warning('The dpkg-control command failed. Here is the content of the rewritten d/control file');
					warning(' used to add relationship substvars for you (in case that is part of the problem).');
					print(" --- Content of $dbgsym_ctrl\n");
					system('cat', $dbgsym_ctrl);
					print(" --- End of content for $dbgsym_ctrl\n");
				}
				error($err);
			}

			reset_perm_and_owner(0644, "${dbgsym_tmp}/DEBIAN/control");
		} elsif ($build_ids) {
			# Only include the build-id if there is no dbgsym package (if
			# there is a dbgsym package, the build-ids into the control
			# file of the dbgsym package)
			push(@debug_info_params, "-DBuild-Ids=${build_ids}");
		}

		# Remove explicit "Multi-Arch: no" headers to avoid auto-rejects by dak.
		push (@pkg_gencontrol_args, '-UMulti-Arch')
			if (package_multiarch($package) eq 'no');

		# Generate and install control file.
		eval {
			doit("dpkg-gencontrol", "-p$package", "-l$changelog", "-T$substvars",
			    "-c${dctrl}", "-P$tmp", @debug_info_params, @pkg_gencontrol_args,
			    @{$dh{U_PARAMS}});
		};
		if (my $err = "$@") {
			if ($dctrl ne 'debian/control') {
				warning('The dpkg-control command failed. Here is the content of the rewritten d/control file');
				warning(' used to add relationship substvars for you (in case that is part of the problem).');
				print(" --- Content of $dctrl\n");
				system('cat', $dctrl);
				print(" --- End of content for $dctrl\n");
			}
			error($err);
		}


		# This chmod is only necessary if the user sets the umask to
		# something odd.
		reset_perm_and_owner(0644, "${tmp}/DEBIAN/control");
	}
};

sub read_dbgsym_file {
	my ($dbgsym_info_file, $dbgsym_info_dir) = @_;
	my $dbgsym_path = "${dbgsym_info_dir}/${dbgsym_info_file}";
	my $result;
	if (-f $dbgsym_path) {
		open(my $fd, '<', $dbgsym_path)
			or error("open $dbgsym_path failed: $!");
		chomp($result = <$fd>);
		$result =~ s/\s++$//;
		close($fd);
	}
	return $result;
}

sub read_dbgsym_migration {
	return read_dbgsym_file('dbgsym-migration', @_);
}

sub read_dbgsym_build_ids {
	my $res = read_dbgsym_file('dbgsym-build-ids', @_);
	my (%seen, @unique);
	return '' if not defined($res);
	for my $id (split(' ', $res)) {
		next if $seen{$id}++;
		push(@unique, $id);
	}
	return join(' ', @unique);
}

=head1 SEE ALSO

L<debhelper(7)>

This program is a part of debhelper.

=head1 AUTHOR

Joey Hess <joeyh@debian.org>

=cut