#!/usr/bin/perl

=encoding UTF-8

=head1 NAME

dh_usrlocal - migrate usr/local directories to maintainer scripts

=cut

use warnings;
use strict;
use Debian::Debhelper::Dh_Lib;
use File::Find;
use File::stat;

our $VERSION = DH_BUILTIN_VERSION;

=head1 SYNOPSIS

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

=head1 DESCRIPTION

B<dh_usrlocal> is a debhelper program that can be used for building packages
that will provide a subdirectory in F</usr/local> when installed.

It finds subdirectories of F<usr/local> in the package build directory, and
removes them, replacing them with maintainer script snippets (unless B<-n>
is used) to create the directories at install time, and remove them when
the package is removed, in a manner compliant with Debian policy. These
snippets are inserted into the maintainer scripts by B<dh_installdeb>. See
L<dh_installdeb(1)> for an explanation of debhelper maintainer script
snippets.

When the I<Rules-Requires-Root> field is not (effectively)
I<binary-targets>, the directories in F</usr/local> will have
ownership root:staff and the mode will be 02775.  These values have
been chosen to comply with the recommendations of the Debian policy
for directories in F</usr/local>.

When I<Rules-Requires-Root> has an effective value of
I<binary-targets>, the owners, groups and permissions will be
preserved with one exception.  If the directory is owned by root:root,
then ownership will be reset to root:staff and mode will be reset to
02775. This is useful, since that is the group and mode policy
recommends for directories in F</usr/local>.

=head1 OPTIONS

=over 4

=item B<-n>, B<--no-scripts>

Do not modify F<postinst>/F<prerm> scripts.

=back

=head1 NOTES

Note that this command is not idempotent. L<dh_prep(1)> 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 CONFORMS TO

Debian policy, version 2.2

=cut

init();

# PROMISE: DH NOOP WITHOUT tmp(usr/local)

foreach my $package (@{$dh{DOPACKAGES}}) {
	my $tmp = tmpdir($package);

	if (-d "$tmp/usr/local") {
		my (@dirs, @justdirs);
		find({bydepth => 1,
		      no_chdir => 1,
		      wanted => sub {
			my $fn = $File::Find::name;
			if (-d $fn) {
				my $user = 'root';
				my $group = 'staff';
				my $mode = '02775';
				if (should_use_root()) {
					my $stat = stat $fn;
					$user = getpwuid $stat->uid;
					$group = getgrgid $stat->gid;
					$mode = sprintf "%04lo", ($stat->mode & 07777);
					if ($stat->uid == 0 && $stat->gid == 0) {
						$group = 'staff';
						$mode = '02775';
					}
				}



				$fn =~ s!^\Q$tmp\E!!;
				return if $fn eq '/usr/local';
				
				# @dirs is in parents-first order for dir creation...
				unshift @dirs, "$fn $mode $user $group";
				# ...whereas @justdirs is depth-first for removal.
				push @justdirs, $fn;
				doit('rmdir', $_);
			}
			else {
				warning("$fn is not a directory");
			}
		      }}, "$tmp/usr/local");
		doit('rmdir', "$tmp/usr/local");
	
		my $bs = "\\";     # A single plain backslash
		my $ebs = $bs x 2; # Escape the backslash from the shell
		# This constructs the body of a 'sed' c\ expression which
		# is parsed by the shell in double-quotes
		my $dirs = join("$ebs\n", sort @dirs);
		pop @justdirs; # don't remove directories directly in /usr/local
		my $justdirs = join("$ebs\n", reverse sort @justdirs);
		if (! $dh{NOSCRIPTS}) { 
			autoscript($package,"postinst", "postinst-usrlocal",
				   "/#DIRS#/ c${ebs}\n${dirs}");
			autoscript($package,"prerm", "prerm-usrlocal",
				   "/#JUSTDIRS#/ c${ebs}\n${justdirs}") if length $justdirs;
		}
	}
}

=head1 SEE ALSO

L<debhelper(7)>

This program is a part of debhelper.

=head1 AUTHOR

Andrew Stribblehill <ads@debian.org>

=cut