#!/usr/bin/perl
#
# dpkg-buildflags
#
# Copyright © 2010-2011 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/>.

use strict;
use warnings;

use Dpkg;
use Dpkg::Gettext;
use Dpkg::ErrorHandling qw(:DEFAULT report);
use Dpkg::BuildFlags;
use Dpkg::Vendor qw(get_current_vendor);

textdomain("dpkg-dev");

sub version {
    printf _g("Debian %s version %s.\n"), $progname, $version;

    printf _g("
This is free software; see the GNU General Public License version 2 or
later for copying conditions. There is NO warranty.
");
}

sub usage {
    printf _g(
"Usage: %s [<command>]")
    . "\n\n" . _g(
"Commands:
  --get <flag>       output the requested flag to stdout.
  --origin <flag>    output the origin of the flag to stdout:
                     value is one of vendor, system, user, env.
  --query-features <area>
                     output the status of features for the given area.
  --list             output a list of the flags supported by the current vendor.
  --export=(sh|make|configure)
                     output something convenient to import the
                     compilation flags in a shell script, in make,
                     or on a ./configure command line.
  --dump             output all compilation flags with their values
  --status           print a synopsis with all parameters affecting the
                     behaviour of dpkg-buildflags and the resulting flags
                     and their origin.
  --help             show this help message.
  --version          show the version.
"), $progname;
}

my ($param, $action);

while (@ARGV) {
    $_ = shift(@ARGV);
    if (m/^--(get|origin|query-features)$/) {
        usageerr(_g("two commands specified: --%s and --%s"), $1, $action)
            if defined($action);
        $action = $1;
        $param = shift(@ARGV);
	usageerr(_g("%s needs a parameter"), $_) unless defined $param;
    } elsif (m/^--export(?:=(sh|make|configure))?$/) {
        usageerr(_g("two commands specified: --%s and --%s"), "export", $action)
            if defined($action);
        my $type = $1 || "sh";
        $action = "export-$type";
    } elsif (m/^--(list|status|dump)$/) {
        usageerr(_g("two commands specified: --%s and --%s"), $1, $action)
            if defined($action);
        $action = $1;
    } elsif (m/^-(\?|-help)$/) {
        usage();
        exit 0;
    } elsif (m/^--version$/) {
        version();
        exit 0;
    } else {
	usageerr(_g("unknown option \`%s'"), $_);
    }
}

$action = "dump" unless defined($action);

my $build_flags = Dpkg::BuildFlags->new();

if ($action eq "list") {
    foreach my $flag ($build_flags->list()) {
	print "$flag\n";
    }
    exit(0);
}

$build_flags->load_config();

if ($action eq "get") {
    if ($build_flags->has($param)) {
	print $build_flags->get($param) . "\n";
	exit(0);
    }
} elsif ($action eq "origin") {
    if ($build_flags->has($param)) {
	print $build_flags->get_origin($param) . "\n";
	exit(0);
    }
} elsif ($action eq "query-features") {
    if ($build_flags->has_features($param)) {
	my %features = $build_flags->get_features($param);
	my $para_shown = 0;
	foreach my $feature (sort keys %features) {
	    print $para_shown++ ? "\n" : "";
	    printf "Feature: %s\n", $feature;
	    printf "Enabled: %s\n", $features{$feature} ? "yes" : "no";
	}
	exit(0);
    }
} elsif ($action =~ m/^export-(.*)$/) {
    my $export_type = $1;
    foreach my $flag ($build_flags->list()) {
	next unless $flag =~ /^[A-Z]/; # Skip flags starting with lowercase
	my $value = $build_flags->get($flag);
	if ($export_type eq "sh") {
	    $value =~ s/"/\"/g;
	    print "export $flag=\"$value\"\n";
	} elsif ($export_type eq "make") {
	    $value =~ s/\$/\$\$/g;
	    print "export $flag := $value\n";
	} elsif ($export_type eq "configure") {
	    print "$flag=\"$value\" ";
	}
    }
    exit(0);
} elsif ($action eq "dump") {
    foreach my $flag ($build_flags->list()) {
	my $value = $build_flags->get($flag);
	print "$flag=$value\n";
    }
    exit(0);
} elsif ($action eq "status") {
    # Prefix everything with "dpkg-buildflags: status: " to allow easy
    # extraction from a build log. Thus we use report with a non-translated
    # type string.

    # First print all environment variables that might have changed the
    # results (only existing ones, might make sense to add an option to
    # also show which ones could have set to modify it).
    my @envvars = Dpkg::BuildEnv::list_accessed();
    for my $envvar (@envvars) {
	if (exists $ENV{$envvar}) {
	    printf report("status", "environment variable %s=%s",
	           $envvar, $ENV{$envvar});
	}
    }
    my $vendor = Dpkg::Vendor::get_current_vendor() || "undefined";
    print report("status", "vendor is $vendor");
    # Then the resulting features:
    foreach my $area (sort $build_flags->get_feature_areas()) {
	my $fs;
	my %features = $build_flags->get_features($area);
	foreach my $feature (sort keys %features) {
	    $fs .= sprintf(" %s=%s", $feature, $features{$feature} ? "yes" : "no");
	}
	print report("status", "$area features:$fs");
    }
    # Then the resulting values (with their origin):
    foreach my $flag ($build_flags->list()) {
	my $value = $build_flags->get($flag);
	my $origin = $build_flags->get_origin($flag);
	my $maintainer = $build_flags->is_maintainer_modified($flag) ? "+maintainer" : "";
	print report("status", "$flag [$origin$maintainer]: $value");
    }
    exit(0);
}

exit(1);