Games-Sokoban/Sokoban.pm

=head1 NAME

Games::Sokoban - load/transform/save sokoban levels in various formats

=head1 SYNOPSIS

 use Games::Sokoban;

=head1 DESCRIPTION

I needed something like this quickly - if you need better docs, you have to ask.

Supports xsb (text), rle, sokevo and a small "binpack" format for input
and output and can normalise levels as well as calculate unique IDs.

=over 4

=cut

package Games::Sokoban;

use common::sense;

use Carp ();
use List::Util ();

our $VERSION = '0.02';

=item $level = new Games::Sokoban [format => "text|rle|binpack"], [data => "###..."]

=cut

sub new {
   my ($class, %arg) = @_;

   my $self = bless \%arg, $class;

   $self->data (delete $self->{data}, delete $self->{format})
      if exists $self->{data};

   $self
}

=item $level = new_from_file Games::Sokoban $path[, $format]

=cut

sub new_from_file {
   my ($class, $path, $format) = @_;

   open my $fh, "<:perlio", $path
      or Carp::croak "$path: $!";
   local $/;

   $class->new (data => (scalar <$fh>), format => $format)
}

sub detect_format($) {
   my ($data) = @_;

   return "text" if $data =~ /^[ #\@\*\$\.\+\015\012\-_]+$/;

   warn $data;#d#
   return "rle"  if $data =~ /^[ #\@\*\$\.\+\015\012\-_|1-9]+$/;
   exit 5;#d#

   my ($a, $b) = unpack "ww", $data;
   return "binpack" if defined $a && defined $b;

   Carp::croak "unable to autodetect sokoban level format";
}

=item $level->data ([$new_data, [$new_data_format]]])

Sets the level from the given data.

=cut

sub data {
   if (@_ > 1) {
      my ($self, $data, $format) = @_;

      $format ||= detect_format $data;

      if ($format eq "text" or $format eq "rle") {
         $data =~ y/-_|/  \n/;
         $data =~ s/(\d)(.)/$2 x $1/ge;
         my @lines = split /[\015\012]+/, $data;
         my $w = List::Util::max map length, @lines;

         $_ .= " " x ($w - length)
            for @lines;

         $self->{data} = join "\n", @lines;

      } elsif ($format eq "binpack") {
         (my ($w, $s), $data) = unpack "wwB*", $data;

         my @enc = ('#', '$', '.', '   ', ' ', '###', '*', '# ');

         $data = join "",
                 map $enc[$_],
                 unpack "C*",
                 pack "(b*)*",
                 unpack "(a3)*", $data;

         # clip extra chars (max. 2)
         my $extra = (length $data) % $w;
         substr $data, -$extra, $extra, "" if $extra;

         (substr $data, $s, 1) =~ y/ ./@+/;

         $self->{data} =
           join "\n",
           map "#$_#",
               "#" x $w,
               (unpack "(a$w)*", $data),
               "#" x $w;
           
      } else {
         Carp::croak "$format: unsupported sokoban level format requested";
      }

      $self->update;
   }

   $_[0]{data}
}

sub pos2xy {
   use integer;

   $_[1] >= 0
      or Carp::croak "illegal buffer offset";

   (
      $_[1] % ($_[0]{w} + 1),
      $_[1] / ($_[0]{w} + 1),
   )
}

sub update {
   my ($self) = @_;

   for ($self->{data}) {
      s/^\n+//;
      s/\n$//;

      /^[^\n]+/ or die;

      $self->{w} = index $_, "\n";
      $self->{h} = y/\n// + 1;
   }
}

=item $text = $level->as_text

=cut

sub as_text {
   my ($self) = @_;

   "$self->{data}\n"
}

=item $binary = $level->as_binpack

=cut

sub as_binpack {
   my ($self) = @_;

   my $binpack = chr $self->{w} - 2;

   my $w = $self->{w};

   my $data = $self->{data};

   # crop away all four borders
   $data =~ s/^#+\n//;
   $data =~ s/#+$//;
   $data =~ s/#$//mg;
   $data =~ s/^#//mg;

   $data =~ y/\n//d;

   $data =~ /[\@\+]/ or die;
   my $s = $-[0];
   (substr $data, $s, 1) =~ y/@+/ ./;

   $data =~ s/\#\#\#/101/g;
   $data =~ s/\ \ \ /110/g;
   $data =~ s/\#\ /111/g;

   $data =~ s/\#/000/g;
   $data =~ s/\ /001/g;
   $data =~ s/\./010/g;
   $data =~ s/\*/011/g;
   $data =~ s/\$/100/g;

   # width, @-offset, data

   pack "wwB*", $w - 2, $s, $data
}

=item @lines = $level->as_lines

=cut

sub as_lines {
   split /\n/, $_[0]{data}
}

=item $line = $level->as_rle

http://www.sokobano.de/wiki/index.php?title=Level_format

=cut

sub as_rle {
   my $data = $_[0]{data};

   $data =~ s/ +$//mg;
   $data =~ y/\n /|-/;
   $data =~ s/((.)\2{2,8})/(length $1) . $2/ge;

   $data
}

=item ($x, $y) = $level->start

Returns (0-based) starting coordinate.

=cut

sub start {
   my ($self) = @_;

   $self->{data} =~ /[\@\+]/ or Carp::croak "level has no starting point";
   $self->pos2xy ($-[0]);
}

=item $level->hflip

=item $level->vflip

=item $level->transpose # topleft to bottomright

=item $level->rotate_90

=item $level->rotate_180

=cut

sub hflip {
   $_[0]{data} = join "\n", map { scalar reverse $_ } split /\n/, $_[0]{data};
}

sub vflip {
   $_[0]{data} = join "\n", reverse split /\n/, $_[0]{data};
}

sub transpose {
   my ($self) = @_;

   # there must be a more elegant way :/
   my @c;

   for (split /\n/, $self->{data}) {
      my $i;

      $c[$i++] .= $_ for split //;
   }

   $self->{data} = join "\n", @c;
   ($self->{w}, $self->{h}) = ($self->{h}, $self->{w})
}

sub rotate_90 {
   $_[0]->vflip;
   $_[0]->transpose;
}

sub rotate_180 {
   $_[0]{data} = reverse $_[0]{data};
}

=item $id = $level->simplify

Detect playable area, crop to smallest size.

=cut

sub simplify {
   my ($self) = @_;

   # first detect playable area
   my ($w, $h) = ($self->{w}, $self->{h});
   my ($x, $y) = $self->start;

   my @data = split /\n/, $self->{data};
   my @mask = @data;

   y/#/\x00/c, y/#/\x7f/ for @mask;

   my @stack = [$x, $y, 0];

   while (@stack) {
      my ($x, $y, $l) = @{ pop @stack };
      my $line = $mask[$y];

      for my $x ($x .. $x + $l) {
         (reverse substr $line, 0, $x + 1) =~ /\x00+/
            or next;

         $l = $+[0];

         $x -= $l - 1;
         (substr $line, $x) =~ /^\x00+/ or die;
         $l = $+[0];

         substr $mask[$y], $x, $l, "\xff" x $l;

         push @stack, [$x, $y - 1, $l - 1] if $y > 0;
         push @stack, [$x, $y + 1, $l - 1] if $y < $h - 1;
      }
   }

   my $walls = "#" x $w;

   for (0 .. $h - 1) {
      $data[$_] = ($data[$_] & $mask[$_]) | ($walls & ~$mask[$_]);
   }

   # reduce borders
   pop   @data while @data > 2 && $data[-2] eq $walls; # bottom
   shift @data while $data[1] eq $walls; # top

   for ($self->{data} = join "\n", @data) {
      s/#$//mg until /[^#]#$/m; # right
      s/^#//mg until /^#[^#]/m; # left
   }

   # phew, done
}

=item $id = $level->normalise

normalises the level map and calculates/returns it's identity code

http://www.sourcecode.se/sokoban/level_id.php, assume uppercase and hex.

=cut

sub normalise {
   my ($self) = @_;

   $self->simplify;

   require Digest::MD5;

   my ($best_md5, $best_data) = "\xff" x 9;

   my $chk = sub {
      my $md5 = substr Digest::MD5::md5 ("$self->{data}\n"), 0, 8;
      if ($md5 lt $best_md5) {
         $best_md5  = $md5;
         $best_data = $self->{data};
      }
   };

   $chk->(); $self->hflip;
   $chk->(); $self->vflip;
   $chk->(); $self->hflip;
   $chk->(); $self->rotate_90;
   $chk->(); $self->hflip;
   $chk->(); $self->vflip;
   $chk->(); $self->hflip;
   $chk->();

   $self->data ($best_data, "text");

   uc unpack "H*", $best_md5
}

=item $levels = Games::Sokoban::load_sokevo $path

Loads a sokevo snapshot/history file and returns all contained levels as
Games::Sokoban objects in an arrayref.

=cut

sub load_sokevo($) {
   open my $fh, "<", $_[0]
      or Carp::croak "$_[0]: $!";

   my @levels;

   while (<$fh>) {
      if (/^##+$/) {
         my $data = $_;
         while (<$fh>) {
            $data .= $_;
            last if /^$/;
         }

         push @levels, new Games::Sokoban data => $data;
      }
   }

   \@levels
}

1;

=back

=head1 AUTHOR

 Marc Lehmann <schmorp@schmorp.de>
 http://home.schmorp.de/

=cut

Revision:	1.6
Committed:	Tue May 11 23:49:40 2010 UTC (14 years ago) by root
Branch:	MAIN
Changes since 1.5:	+46 -42 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	root	1.1	=head1 NAME
2
3			Games::Sokoban - load/transform/save sokoban levels in various formats
4
5			=head1 SYNOPSIS
6
7			use Games::Sokoban;
8
9			=head1 DESCRIPTION
10
11			I needed something like this quickly - if you need better docs, you have to ask.
12
13	root	1.2	Supports xsb (text), rle, sokevo and a small "binpack" format for input
14			and output and can normalise levels as well as calculate unique IDs.
15	root	1.1
16			=over 4
17
18			=cut
19
20			package Games::Sokoban;
21
22			use common::sense;
23
24			use Carp ();
25			use List::Util ();
26
27	root	1.3	our $VERSION = '0.02';
28	root	1.1
29	root	1.4	=item $level = new Games::Sokoban [format => "text\|rle\|binpack"], [data => "###..."]
30	root	1.1
31			=cut
32
33			sub new {
34			my ($class, %arg) = @_;
35
36			my $self = bless \%arg, $class;
37
38			$self->data (delete $self->{data}, delete $self->{format})
39			if exists $self->{data};
40
41			$self
42			}
43
44			=item $level = new_from_file Games::Sokoban $path[, $format]
45
46			=cut
47
48			sub new_from_file {
49			my ($class, $path, $format) = @_;
50
51			open my $fh, "<:perlio", $path
52			or Carp::croak "$path: $!";
53			local $/;
54
55			$class->new (data => (scalar <$fh>), format => $format)
56			}
57
58			sub detect_format($) {
59			my ($data) = @_;
60
61			return "text" if $data =~ /^[ #\@\*\$\.\+\015\012\-_]+$/;
62
63			warn $data;#d#
64			return "rle" if $data =~ /^[ #\@\*\$\.\+\015\012\-_\|1-9]+$/;
65			exit 5;#d#
66
67			my ($a, $b) = unpack "ww", $data;
68			return "binpack" if defined $a && defined $b;
69
70			Carp::croak "unable to autodetect sokoban level format";
71			}
72
73			=item $level->data ([$new_data, [$new_data_format]]])
74
75	root	1.6	Sets the level from the given data.
76
77	root	1.1	=cut
78
79			sub data {
80	root	1.6	if (@_ > 1) {
81			my ($self, $data, $format) = @_;
82
83			$format \|\|= detect_format $data;
84	root	1.1
85	root	1.6	if ($format eq "text" or $format eq "rle") {
86			$data =~ y/-_\|/ \n/;
87			$data =~ s/(\d)(.)/$2 x $1/ge;
88			my @lines = split /[\015\012]+/, $data;
89			my $w = List::Util::max map length, @lines;
90
91			$_ .= " " x ($w - length)
92			for @lines;
93
94			$self->{data} = join "\n", @lines;
95
96			} elsif ($format eq "binpack") {
97			(my ($w, $s), $data) = unpack "wwB*", $data;
98
99			my @enc = ('#', '$', '.', ' ', ' ', '###', '*', '# ');
100
101			$data = join "",
102			map $enc[$_],
103			unpack "C*",
104			pack "(b)",
105			unpack "(a3)*", $data;
106
107			# clip extra chars (max. 2)
108			my $extra = (length $data) % $w;
109			substr $data, -$extra, $extra, "" if $extra;
110
111			(substr $data, $s, 1) =~ y/ ./@+/;
112
113			$self->{data} =
114			join "\n",
115			map "#$_#",
116			"#" x $w,
117			(unpack "(a$w)*", $data),
118			"#" x $w;
119
120			} else {
121			Carp::croak "$format: unsupported sokoban level format requested";
122			}
123	root	1.1
124	root	1.6	$self->update;
125	root	1.1	}
126
127	root	1.6	$_[0]{data}
128	root	1.1	}
129
130			sub pos2xy {
131			use integer;
132
133			$_[1] >= 0
134			or Carp::croak "illegal buffer offset";
135
136			(
137			$_[1] % ($_[0]{w} + 1),
138			$_[1] / ($_[0]{w} + 1),
139			)
140			}
141
142			sub update {
143			my ($self) = @_;
144
145			for ($self->{data}) {
146			s/^\n+//;
147			s/\n$//;
148
149			/^[^\n]+/ or die;
150
151			$self->{w} = index $_, "\n";
152			$self->{h} = y/\n// + 1;
153			}
154			}
155
156			=item $text = $level->as_text
157
158			=cut
159
160			sub as_text {
161			my ($self) = @_;
162
163			"$self->{data}\n"
164			}
165
166			=item $binary = $level->as_binpack
167
168			=cut
169
170			sub as_binpack {
171			my ($self) = @_;
172
173			my $binpack = chr $self->{w} - 2;
174
175			my $w = $self->{w};
176
177			my $data = $self->{data};
178
179			# crop away all four borders
180			$data =~ s/^#+\n//;
181			$data =~ s/#+$//;
182			$data =~ s/#$//mg;
183			$data =~ s/^#//mg;
184
185			$data =~ y/\n//d;
186
187			$data =~ /[\@\+]/ or die;
188			my $s = $-[0];
189			(substr $data, $s, 1) =~ y/@+/ ./;
190
191			$data =~ s/\#\#\#/101/g;
192			$data =~ s/\ \ \ /110/g;
193			$data =~ s/\#\ /111/g;
194
195			$data =~ s/\#/000/g;
196			$data =~ s/\ /001/g;
197			$data =~ s/\./010/g;
198			$data =~ s/\*/011/g;
199			$data =~ s/\$/100/g;
200
201			# width, @-offset, data
202
203			pack "wwB*", $w - 2, $s, $data
204			}
205
206			=item @lines = $level->as_lines
207
208			=cut
209
210			sub as_lines {
211			split /\n/, $_[0]{data}
212			}
213
214	root	1.5	=item $line = $level->as_rle
215	root	1.1
216			http://www.sokobano.de/wiki/index.php?title=Level_format
217
218			=cut
219
220			sub as_rle {
221			my $data = $_[0]{data};
222
223			$data =~ s/ +$//mg;
224			$data =~ y/\n /\|-/;
225			$data =~ s/((.)\2{2,8})/(length $1) . $2/ge;
226
227			$data
228			}
229
230			=item ($x, $y) = $level->start
231
232	root	1.5	Returns (0-based) starting coordinate.
233
234	root	1.1	=cut
235
236			sub start {
237			my ($self) = @_;
238
239			$self->{data} =~ /[\@\+]/ or Carp::croak "level has no starting point";
240			$self->pos2xy ($-[0]);
241			}
242
243			=item $level->hflip
244
245			=item $level->vflip
246
247			=item $level->transpose # topleft to bottomright
248
249			=item $level->rotate_90
250
251			=item $level->rotate_180
252
253			=cut
254
255			sub hflip {
256			$_[0]{data} = join "\n", map { scalar reverse $_ } split /\n/, $_[0]{data};
257			}
258
259			sub vflip {
260			$_[0]{data} = join "\n", reverse split /\n/, $_[0]{data};
261			}
262
263			sub transpose {
264			my ($self) = @_;
265
266			# there must be a more elegant way :/
267			my @c;
268
269			for (split /\n/, $self->{data}) {
270			my $i;
271
272			$c[$i++] .= $_ for split //;
273			}
274
275			$self->{data} = join "\n", @c;
276			($self->{w}, $self->{h}) = ($self->{h}, $self->{w})
277			}
278
279			sub rotate_90 {
280			$_[0]->vflip;
281			$_[0]->transpose;
282			}
283
284			sub rotate_180 {
285			$_[0]{data} = reverse $_[0]{data};
286			}
287
288			=item $id = $level->simplify
289
290			Detect playable area, crop to smallest size.
291
292			=cut
293
294			sub simplify {
295			my ($self) = @_;
296
297			# first detect playable area
298			my ($w, $h) = ($self->{w}, $self->{h});
299			my ($x, $y) = $self->start;
300
301			my @data = split /\n/, $self->{data};
302			my @mask = @data;
303
304			y/#/\x00/c, y/#/\x7f/ for @mask;
305
306			my @stack = [$x, $y, 0];
307
308			while (@stack) {
309			my ($x, $y, $l) = @{ pop @stack };
310			my $line = $mask[$y];
311
312			for my $x ($x .. $x + $l) {
313			(reverse substr $line, 0, $x + 1) =~ /\x00+/
314			or next;
315
316			$l = $+[0];
317
318			$x -= $l - 1;
319			(substr $line, $x) =~ /^\x00+/ or die;
320			$l = $+[0];
321
322			substr $mask[$y], $x, $l, "\xff" x $l;
323
324			push @stack, [$x, $y - 1, $l - 1] if $y > 0;
325			push @stack, [$x, $y + 1, $l - 1] if $y < $h - 1;
326			}
327			}
328
329			my $walls = "#" x $w;
330
331			for (0 .. $h - 1) {
332			$data[$_] = ($data[$_] & $mask[$_]) \| ($walls & ~$mask[$_]);
333			}
334
335			# reduce borders
336			pop @data while @data > 2 && $data[-2] eq $walls; # bottom
337			shift @data while $data[1] eq $walls; # top
338
339			for ($self->{data} = join "\n", @data) {
340			s/#$//mg until /[^#]#$/m; # right
341			s/^#//mg until /^#[^#]/m; # left
342			}
343
344			# phew, done
345			}
346
347			=item $id = $level->normalise
348
349			normalises the level map and calculates/returns it's identity code
350
351			http://www.sourcecode.se/sokoban/level_id.php, assume uppercase and hex.
352
353			=cut
354
355			sub normalise {
356			my ($self) = @_;
357
358			$self->simplify;
359
360			require Digest::MD5;
361
362			my ($best_md5, $best_data) = "\xff" x 9;
363
364			my $chk = sub {
365			my $md5 = substr Digest::MD5::md5 ("$self->{data}\n"), 0, 8;
366			if ($md5 lt $best_md5) {
367			$best_md5 = $md5;
368			$best_data = $self->{data};
369			}
370			};
371
372			$chk->(); $self->hflip;
373			$chk->(); $self->vflip;
374			$chk->(); $self->hflip;
375			$chk->(); $self->rotate_90;
376			$chk->(); $self->hflip;
377			$chk->(); $self->vflip;
378			$chk->(); $self->hflip;
379			$chk->();
380
381			$self->data ($best_data, "text");
382
383			uc unpack "H*", $best_md5
384			}
385
386			=item $levels = Games::Sokoban::load_sokevo $path
387
388			Loads a sokevo snapshot/history file and returns all contained levels as
389			Games::Sokoban objects in an arrayref.
390
391			=cut
392
393			sub load_sokevo($) {
394			open my $fh, "<", $_[0]
395			or Carp::croak "$_[0]: $!";
396
397			my @levels;
398
399			while (<$fh>) {
400			if (/^##+$/) {
401			my $data = $_;
402			while (<$fh>) {
403			$data .= $_;
404			last if /^$/;
405			}
406
407			push @levels, new Games::Sokoban data => $data;
408			}
409			}
410
411			\@levels
412			}
413
414			1;
415
416			=back
417
418			=head1 AUTHOR
419
420			Marc Lehmann <schmorp@schmorp.de>
421			http://home.schmorp.de/
422
423			=cut
424