#!/usr/bin/perl -w

=head1 NAME

dh_cligacpolicy - creates and installs a CLI policy file for a package

=cut

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

=head1 SYNOPSIS

B<dh_cligacpolicy> [S<I<debhelper options>>] [B<-n>]

=head1 DESCRIPTION

dh_cligacpolicy is a debhelper program that is responsible for creating,
compiling, and installing policy files for a Debian package.  This
automatically includes postinst and prerm commands needed to install
these policies into the system.

=head1 OPTIONS

=over 4

=item B<-n>, B<--noscripts>

Do not modify postinst/prerm scripts.

=back

=head1 FILE FORMAT

This file uses the I<debian/cligacpolicy> files (either
I<policyassemblies> or I<debian/packagename.cligacpolicy>) to generate
the policy file. It supports multiple versions of the policy,
including mapping multiple versions to a single file.

The file format of the I<cligacpolicy> file consists of five
properties per line, each one separated by whitespace.

=over 4

=item B<Keyfile> is a path, from the package root, to the .snk file
used to sign the assembly.

=item B<Assembly> is the name of the assembly, without the .dll
extension. For example, for log4net.dll, use I<log4net>.

=item B<Version Range> can be a single four-part version, such as
1.2.3.4, or a full range, such as 1.2.3.4-1.2.6.7. For a single line,
the first two numbers must be identical. To have an assembly apply to
multiple versions, such as 1.2.0.0 to 2.4.0.0, there needs to be one
line for each version range.

=item B<Assembly version> is the version of the assembly being
=built.

=item B<Priority> defines the priority of the policy files.
Typically, each version will increase the priority and
contains all the policy controls for prior versions.

=back

The fields can be separated with spaces or tabs. Comments start the
line with I<#> characters and blank lines are ignored.

=head1 NOTES

Note that this command is not idempotent. "dh_prep" should be called
between invocations of this command. Otherwise, it may cause multiple
instances of the same text to be added to maintainer scripts.

=head1 EXAMPLE

For the log4net 1.2.10.0 version, a policy file is used to map all
versions from 1.2.8.0 to 1.2.9.99 into the current version.

debian/log4net.snk log4net 1.2.8.0-1.2.9.99 1.2.10.0 10

=cut

# Set up debhelper
init();

{
  local $/="";
  open(FILE, 'debian/control');
  my @filedata = <FILE>;
  close(FILE);
  if (!($filedata[0] =~ /Build-Depends(-Indep)?: .*cli-common-dev \(>= 0\.5\.7\)/)) {
      warning("Warning! No Build-Depends(-Indep) on cli-common-dev (>= 0.5.7)!");
  }
}

# Go through each of the packages being built
my $errors = 0;

# PROMISE: DH NOOP WITHOUT cligacpolicy

foreach my $package (@{$dh{DOPACKAGES}})
{
    # Set up our internal variables
    my $tmp = tmpdir($package);
    my $policy = pkgfile($package, "cligacpolicy");
    my %policies = ();
    
    # If $policy is blank, then there is no file
    next if $policy eq "";

    # Load the policy file into memory.
    my ($keyfile, $pkg_tmp, $cli_dir, $token, $priority);
    open POLICY, "<$policy" or die "E: Can't open $policy ($!)";

    while (<POLICY>)
    {
	# Clean up the line and ignore blanks and comments
	chomp;
	s/^\s+//;
	s/\s+$//;
	next if /^\#/;
	next if /^$/;

	# Each line consists of six parts:
	#   1. snk file for encryption, relative to the package root
	#   2. Assembly name
	#   3. Versions to map from
	#   4. Versions to map to
	#   5. Priority of this policy

	my ($snk, $assembly, $map, $version, $priority) =
	    split(/\s+/);

	# Verify the fields
	my $version_map;

	# Remove the .dll to normalize it
	$assembly =~ s/\.dll$//;

	# Get the token from the file
	my $cmd = "/usr/bin/cli-sn -t '$snk' | grep 'Public Key' "
	    . "| cut -f 2- -d :";
	my $token = `$cmd`;
	# FIXME: error handling here!
	$token =~ s/^\s*(.*?)\s*$/$1/sg;

	# Check the version numbers
	if ($map =~ /^(\d+\.\d+)\.\d+\.\d+$/)
	{
	    $version_map = $1;
	}
	else
	{
	    if ($map =~ /^(\d+\.\d+)\.\d+\.\d+-(\d+\.\d+)\.\d+\.\d+$/)
	    {
		if ($1 ne $2)
		{
		    $errors = 1;
		    print STDERR "E: $package $.: Version ranges ($map) must "
			. "have the first two digits of the version the same. "
			. "Use two different lines for this line.\n";
		    next;
		}

		$version_map = $1;
	    }
	    else
	    {
		$errors = 1;
		print STDERR "E: $package $.: The version field ($map) "
		    . "must be in the following format: "
		    . "'A.B.C.D' or 'A.B.C.D-E.F.G.H'\n";
		next;
	    }
	}

	# We have now gathered up everything we need. We use a hash to
	# consolidate all the various bindings into the unique
	# combinations of policy files we need.
	my $pk = join("--", $snk, $assembly, $version_map, $priority);

 	$policies{$pk} .=
 	    join("\n",
 		 '    <assemblyBinding '
		 . 'xmlns="urn:schemas-microsoft-com:asm.v1">',
 		 '      <dependentAssembly>',
 		 "        <assemblyIdentity name=\"$assembly\" "
		 . "publicKeyToken=\"$token\"/>",
 		 "          <bindingRedirect oldVersion="
 		 . "\"$map\" newVersion=\"$version\"/>",
 		 "      </dependentAssembly>",
 		 "    </assemblyBinding>") . "\n";
    }

    close POLICY;

    # Make sure the policies.d directory exists
    install_dir("$tmp/usr/share/cli-common/policies.d/$package");

    # Once all the various <assemblyBinding> tags are consolidated, we
    # then generate the policy files. This will result in one policy file for
    # a given assembly, key file, and A.B version.
    foreach my $pk (keys %policies)
    {
	# Get the pkg_dir
	my ($snk, $assembly, $version_map, $priority) =
	    split(/--/, $pk);
	my $pkg_dir = "usr/share/cli-common/policies.d/$package";
	my $tmp_pkg_dir = "$tmp/$pkg_dir";
	my $policy_file = "$version_map.$assembly";

	# Open the policy file chooser
	open CHOOSER, ">$tmp/usr/share/cli-common/policies.d/"
	    . sprintf("%03d-%s.%s", $priority, $version_map, $assembly);
	print CHOOSER "/$pkg_dir/policy.$policy_file.dll\n";
	close CHOOSER;

	# Open up the file
	unless (open PF, ">$tmp_pkg_dir/policy.$policy_file.config")
	{
	    $errors = 1;
	    print STDERR "E: $package: Cannot write $policy_file.config\n";
	    print STDERR "E: $package: $!\n";
	    next;
	}

	# Write out the policy file
	print PF "<configuration>\n  <runtime>\n";
	print PF $policies{$pk};
	print PF "  </runtime>\n</configuration>\n";
	close PF;

 	# Compile the assembly file. We have to change directory first
 	# because of AL limitation.
 	system("cd $tmp_pkg_dir/ && /usr/bin/cli-al "
 	       . "/link:policy.$policy_file.config "
 	       . "/out:policy.$policy_file.dll "
 	       . "/keyfile:" . $ENV{PWD} . "/$snk");

 	# Clean up the config file
 	#unlink("$tmp_pkg_dir/policy.$policy_file.config");

	# Set up the scripts
	if (! $dh{NOSCRIPTS})
	{
	    autoscript($package, "postinst", "postinst-cligacpolicy",
		       "s/#ASSEMBLY# #VERSION#/$assembly $version_map/");
	    autoscript($package, "postrm", "postrm-cligacpolicy",
		       "s/#ASSEMBLY# #VERSION#/$assembly $version_map/");
	}
    }    
}

# Finish up
exit $errors;

=head1 SEE ALSO

L<debhelper(7)>

This program is a part of cli-common-dev.

=head1 AUTHOR

Dylan R. E. Moonfire <debian@mfgames.com>

=cut

#      <configuration>
#         <runtime>
#            <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
#             <dependentAssembly>
#               <assemblyIdentity name="foo" publicKeyToken="35e10195dab3c99f" />
#               <bindingRedirect oldVersion="1.2.0.0-1.2.10.0" newVersion="1.3.0.0"/>
#      	   </dependentAssembly>
#            </assemblyBinding>
#         </runtime>
#      </configuration>