File: memory.pm

package info (click to toggle)
bioperl 1.6.924-1
  • links: PTS, VCS
  • area: main
  • in suites: jessie, jessie-kfreebsd
  • size: 50,776 kB
  • ctags: 11,412
  • sloc: perl: 175,865; xml: 27,565; lisp: 2,034; sh: 1,958; makefile: 19
file content (796 lines) | stat: -rw-r--r-- 22,748 bytes parent folder | download
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
package Bio::DB::SeqFeature::Store::memory;

=head1 NAME

Bio::DB::SeqFeature::Store::memory -- In-memory implementation of Bio::DB::SeqFeature::Store

=head1 SYNOPSIS

  use Bio::DB::SeqFeature::Store;

  # Open the sequence database
  my $db      = Bio::DB::SeqFeature::Store->new( -adaptor => 'memory',
                                                 -dsn     => '/var/databases/test');
  # search... by id
  my @features = $db->fetch_many(@list_of_ids);

  # ...by name
  @features = $db->get_features_by_name('ZK909');

  # ...by alias
  @features = $db->get_features_by_alias('sma-3');

  # ...by type
  @features = $db->get_features_by_type('gene');

  # ...by location
  @features = $db->get_features_by_location(-seq_id=>'Chr1',-start=>4000,-end=>600000);

  # ...by attribute
  @features = $db->get_features_by_attribute({description => 'protein kinase'})

  # ...by the GFF "Note" field
  @result_list = $db->search_notes('kinase');

  # ...by arbitrary combinations of selectors
  @features = $db->features(-name => $name,
                            -type => $types,
                            -seq_id => $seqid,
                            -start  => $start,
                            -end    => $end,
                            -attributes => $attributes);

  # ...using an iterator
  my $iterator = $db->get_seq_stream(-name => $name,
                                     -type => $types,
                                     -seq_id => $seqid,
                                     -start  => $start,
                                     -end    => $end,
                                     -attributes => $attributes);

  while (my $feature = $iterator->next_seq) {
    # do something with the feature
  }

  # ...limiting the search to a particular region
  my $segment  = $db->segment('Chr1',5000=>6000);
  my @features = $segment->features(-type=>['mRNA','match']);

  # getting & storing sequence information
  # Warning: this returns a string, and not a PrimarySeq object
  $db->insert_sequence('Chr1','GATCCCCCGGGATTCCAAAA...');
  my $sequence = $db->fetch_sequence('Chr1',5000=>6000);

  # what feature types are defined in the database?
  my @types    = $db->types;

  # create a new feature in the database
  my $feature = $db->new_feature(-primary_tag => 'mRNA',
                                 -seq_id      => 'chr3',
                                 -start      => 10000,
                                 -end        => 11000);

=head1 DESCRIPTION

Bio::DB::SeqFeature::Store::memory is the in-memory adaptor for
Bio::DB::SeqFeature::Store. You will not create it directly, but
instead use Bio::DB::SeqFeature::Store-E<gt>new() to do so.

See L<Bio::DB::SeqFeature::Store> for complete usage instructions.

=head2 Using the memory adaptor

Before using the memory adaptor, populate a readable-directory on the
file system with annotation and/or sequence files. The annotation
files must be in GFF3 format, and sholud end in the extension .gff or
.gff3. They may be compressed with "compress", "gzip" or "bzip2" (in
which case the appropriate compression extension must be present as
well.)

You may include sequence data inline in the GFF3 files, or put the
sequence data in one or more separate FASTA-format files. These files
must end with .fa or .fasta and may be compressed. Because of the way
the adaptor works, you will get much better performance if you keep
the sequence data in separate FASTA files.

Initialize the database using the -dsn option. This should point to
the directory creating the annotation and sequence files, or to a
single GFF3 file. Examples:


  # load all GFF3 and FASTA files located in /var/databases/test directory
  $db  = Bio::DB::SeqFeature::Store->new( -adaptor => 'memory',
                                          -dsn     => '/var/databases/test');


  # load the data in a single compressed GFF3 file located at
  # /usr/annotations/worm.gf33.gz
  $db  = Bio::DB::SeqFeature::Store->new( -adaptor => 'memory',
                                          -dsn     => '/usr/annotations/worm.gff3.gz');

For compatibility with the Bio::DB::GFF memory adaptor, -gff is
recognized as an alias for -dsn.

See L<Bio::DB::SeqFeature::Store> for all the access methods supported
by this adaptor. The various methods for storing and updating features
and sequences into the database are supported, including GFF3 loading
support, but since this is an in-memory adaptor all changes you make
will be lost when the script exits.

=cut

use strict;
use base 'Bio::DB::SeqFeature::Store';
use Bio::DB::SeqFeature::Store::GFF3Loader;
use Bio::DB::GFF::Util::Rearrange 'rearrange';
use File::Temp 'tempdir';
use IO::File;
use Bio::DB::Fasta;
use File::Glob ':glob';

use constant BINSIZE => 10_000;

###
# object initialization
#
sub init {
  my ($self, $args) = @_;
  $self->SUPER::init($args);
  $self->{_data}     = {};
  $self->{_children} = {};
  $self->{_index}    = {};
  $self;
}

sub post_init {
  my $self = shift;
  my ($file_or_dir) = rearrange([['DIR','DSN','FILE','GFF']],@_);
  return unless $file_or_dir;

  my $loader = Bio::DB::SeqFeature::Store::GFF3Loader->new(-store    => $self,
							   -sf_class => $self->seqfeature_class) 
    or $self->throw("Couldn't create GFF3Loader");
  my @argv;
  if (-d $file_or_dir) {
    @argv = (
	     bsd_glob("$file_or_dir/*.size*"),
	     bsd_glob("$file_or_dir/*.gff"),            bsd_glob("$file_or_dir/*.gff3"),
	     bsd_glob("$file_or_dir/*.gff.{gz,Z,bz2}"), bsd_glob("$file_or_dir/*.gff3.{gz,Z,bz2}")
	     );
  } else {
    @argv = $file_or_dir;
  }
  local $self->{file_or_dir} = $file_or_dir;
  $loader->load(@argv);
  warn $@ if $@;
}

sub commit { # reindex fasta files
  my $self = shift;

  my $db;
  if (my $fh = $self->{fasta_fh}) {
      $fh->close;
      $db = Bio::DB::Fasta->new($self->{fasta_file});
  } elsif (exists $self->{file_or_dir} && -d $self->{file_or_dir}) {
      $db = Bio::DB::Fasta->new($self->{file_or_dir});
  }
  $self->{fasta_db} = $db if $db;
}

sub can_store_parentage { 1 }

# return a hash ref in which each key is primary id
sub data {
  shift->{_data};
}

sub _init_database { shift->init }

sub _store {
  my $self    = shift;
  my $indexed = shift;
  my @objs    = @_;
  my $data = $self->data;
  my $count = 0;
  for my $obj (@objs) {
    # Add unique ID to feature if needed
    my $primary_id = $self->_autoid($obj);
    # Store feature (overwriting any existing feature with the same primary ID
    # as required by Bio::DB::SF::Store)
    $data->{$primary_id} = $obj;
    if ($indexed) {
      $self->{_index}{ids}{$primary_id} = undef;
      $self->_update_indexes($obj);
    }
    $count++;
  }
  return $count;
}


sub _autoid {
  # If a feature has no ID, assign it a unique ID
  my ($self, $obj) = @_;
  my $data = $self->data;
  my $primary_id = $obj->primary_id;
  if (not defined $primary_id) {
    # Create a unique ID
    $primary_id = 1 + scalar keys %{$data};
    while (exists $data->{$primary_id}) {
      $primary_id++;
    }
    $obj->primary_id($primary_id);
  }
  return $primary_id;
}


sub _deleteid {
  my ($self, $id) = @_;
  if (exists $self->{_index}{ids}{$id}) {
    # $indexed was true
    $self->_update_indexes( $self->fetch($id), 1 );
    delete $self->{_index}{ids}{$id};
  }
  delete $self->data->{$id};
  return 1;
}

sub _fetch {
  my ($self, $id) = @_;
  return $self->data->{$id};
}

sub _add_SeqFeature {
  my ($self, $parent, @children) = @_;
  my $count = 0;
  my $parent_id = ref $parent ? $parent->primary_id : $parent;
  defined $parent_id or $self->throw("Parent $parent should have a primary ID");
  for my $child (@children) {
    my $child_id = ref $child ? $child->primary_id : $child;
    defined $child_id or $self->throw("Child $child should have a primary ID");
    $self->{_children}{$parent_id}{$child_id}++;
    $count++;
  }
  return $count;
}

sub _fetch_SeqFeatures {
  my ($self, $parent, @types) = @_;
  my $parent_id = $parent->primary_id;
  defined $parent_id or $self->throw("Parent $parent should have a primary ID");
  my @children_ids  = keys %{$self->{_children}{$parent_id}};
  my @children      = map {$self->fetch($_)} @children_ids;
  
  if (@types) {
    my $data;
    for my $c (@children) {
      push @{$$data{$c->primary_tag}{$c->source_tag||''}}, $c;
    }
    @children = ();
    for my $type (@types) {
      $type .= ':' if (not $type =~ m/:/);
      my ($primary_tag, undef, $source_tag) = ($type =~ m/^(.*?)(:(.*?))$/);
      $source_tag ||= '';
      if ($source_tag eq '') {
        for my $source (keys %{$$data{$primary_tag}}) {
          if (exists $$data{$primary_tag}{$source_tag}) {
            push @children, @{$$data{$primary_tag}{$source_tag}};
          }
        }
      } else {
        if (exists $$data{$primary_tag}{$source_tag}) {
          push @children, @{$$data{$primary_tag}{$source_tag}};
        }
      }
    }
  }

  return @children;
}

sub _update_indexes {
  my ($self, $obj, $del) = @_;
  defined (my $id = $obj->primary_id) or return;
  $del ||= 0;
  $self->_update_name_index($obj,$id, $del);
  $self->_update_type_index($obj,$id, $del);
  $self->_update_location_index($obj, $id, $del);
  $self->_update_attribute_index($obj,$id, $del);
}

sub _update_name_index {
  my ($self, $obj, $id, $del) = @_;
  my ($names, $aliases) = $self->feature_names($obj);
  foreach (@$names) {
    if (not $del) {
      $self->{_index}{name}{lc $_}{$id}   = 1;
    } else {
      delete $self->{_index}{name}{lc $_}{$id};
      if (scalar keys %{ $self->{_index}{name}{lc $_} } == 0) {
        delete $self->{_index}{name}{lc $_};
      }
    };
  }
  foreach (@$aliases) {
    if (not $del) {
      $self->{_index}{name}{lc $_}{$id} ||= 2;
    } else {
      delete $self->{_index}{name}{lc $_}{$id};
      if (scalar keys %{ $self->{_index}{name}{lc $_} } == 0) {
        delete $self->{_index}{name}{lc $_};
      }
    }
  }
}

sub _update_type_index {
  my ($self, $obj, $id, $del) = @_;
  my $primary_tag = lc($obj->primary_tag) || return;
  my $source_tag  = lc($obj->source_tag || '');
  if (not $del) {
    $self->{_index}{type}{$primary_tag}{$source_tag}{$id} = undef;
  } else {
    delete $self->{_index}{type}{$primary_tag}{$source_tag}{$id};
    if ( scalar keys %{$self->{_index}{type}{$primary_tag}{$source_tag}} == 0 ) {
      delete $self->{_index}{type}{$primary_tag}{$source_tag};
      if (scalar keys %{$self->{_index}{type}{$primary_tag}} == 0 ) {
        delete $self->{_index}{type}{$primary_tag};
      }
    }
  }
}

sub _update_location_index {
  my ($self, $obj, $id, $del) = @_;
  my $seq_id      = $obj->seq_id || '';
  my $start       = $obj->start  || 0;
  my $end         = $obj->end    || 0;
  my $strand      = $obj->strand;
  my $bin_min     = int $start/BINSIZE;
  my $bin_max     = int $end/BINSIZE;
  for (my $bin = $bin_min; $bin <= $bin_max; $bin++ ) {
    if (not $del) {
      $self->{_index}{location}{lc $seq_id}{$bin}{$id} = undef;
    } else {
      delete $self->{_index}{location}{lc $seq_id}{$bin}{$id};
      if (scalar keys %{$self->{_index}{location}{lc $seq_id}{$bin}{$id}} == 0) {
        delete $self->{_index}{location}{lc $seq_id}{$bin}{$id};
      }
      if (scalar keys %{$self->{_index}{location}{lc $seq_id}{$bin}} == 0) {
        delete $self->{_index}{location}{lc $seq_id}{$bin};
      }
      if (scalar keys %{$self->{_index}{location}{lc $seq_id}} == 0) {
        delete $self->{_index}{location}{lc $seq_id};
      }
    }
  }
}

sub _update_attribute_index {
  my ($self, $obj, $id, $del) = @_;
  for my $tag ($obj->get_all_tags) {
    for my $value ($obj->get_tag_values($tag)) {
      if (not $del) {
        $self->{_index}{attribute}{lc $tag}{lc $value}{$id} = undef;
      } else {
        delete $self->{_index}{attribute}{lc $tag}{lc $value}{$id};
        if ( scalar keys %{$self->{_index}{attribute}{lc $tag}{lc $value}} == 0) {
          delete $self->{_index}{attribute}{lc $tag}{lc $value};
        }
        if ( scalar keys %{$self->{_index}{attribute}{lc $tag}} == 0) {
          delete $self->{_index}{attribute}{lc $tag};
        }
        if ( scalar keys %{$self->{_index}{attribute}} == 0) {
          delete $self->{_index}{attribute};
        }
      }
    }
  }
}

sub _features {
  my $self = shift;
  my ($seq_id,$start,$end,$strand,
      $name,$class,$allow_aliases,
      $types,
      $attributes,
      $range_type,
      $iterator
     ) = rearrange([['SEQID','SEQ_ID','REF'],'START',['STOP','END'],'STRAND',
		    'NAME','CLASS','ALIASES',
		    ['TYPES','TYPE','PRIMARY_TAG'],
		    ['ATTRIBUTES','ATTRIBUTE'],
		    'RANGE_TYPE',
		    'ITERATOR',
		   ],@_);

  my (@from,@where,@args,@group);
  $range_type ||= 'overlaps';

  my @result;
  unless (defined $name or defined $seq_id or defined $types or defined $attributes) {
    @result = keys %{$self->{_index}{ids}};
  }

  my %found  = ();
  my $result = 1;

  if (defined($name)) {
    # hacky backward compatibility workaround
    undef $class if $class && $class eq 'Sequence';
    $name     = "$class:$name" if defined $class && length $class > 0;
    $result &&= $self->filter_by_name($name,$allow_aliases,\%found);
  }

  if (defined $seq_id) {
    $result &&= $self->filter_by_location($seq_id,$start,$end,$strand,$range_type,\%found);
  }

  if (defined $types) {
    $result &&= $self->filter_by_type($types,\%found);
  }

  if (defined $attributes) {
    $result &&= $self->filter_by_attribute($attributes,\%found);
  }

  push @result,keys %found if $result;
  return $iterator ? Bio::DB::SeqFeature::Store::memory::Iterator->new($self,\@result)
                   : map {$self->fetch($_)} @result;
}


sub filter_by_type {
  my ($self, $types_req, $filter) = @_;
  my @types_req = ref $types_req eq 'ARRAY' ?  @$types_req : $types_req;

  my $types = $self->{_index}{type};
  my @types_found = $self->find_types(\@types_req);

  my @results;
  for my $type_found (@types_found) {
    my ($primary_tag, undef, $source_tag) = ($type_found =~ m/^(.*?)(:(.*?))$/);
    next unless exists $types->{$primary_tag}{$source_tag};
    push @results, keys %{$types->{$primary_tag}{$source_tag}};
  }

  $self->update_filter($filter,\@results);
}

sub find_types {
  my ($self, $types_req) = @_;
  my @types_found;

  my $types = $self->{_index}{type};

  for my $type_req (@$types_req) {

    # Type is the primary tag and an optional source tag
    my ($primary_tag, $source_tag);
    if (ref $type_req && $type_req->isa('Bio::DB::GFF::Typename')) {
      $primary_tag = $type_req->method;
      $source_tag  = $type_req->source;
    } else {
      ($primary_tag, undef, $source_tag) = ($type_req =~ m/^(.*?)(:(.*))?$/); 
    }
    ($primary_tag, $source_tag) = (lc $primary_tag, lc($source_tag || ''));

    next if not exists $$types{$primary_tag};

    if ($source_tag eq '') {
      # Match all sources for this primary_tag
      push @types_found, map {"$primary_tag:$_"} (keys %{ $$types{$primary_tag} });
    } else {
      # Match only the requested source
      push @types_found, "$primary_tag:$source_tag";
    }

  }
  return @types_found;
}

sub attributes {
  my $self = shift;
  return keys %{$self->{_index}{attribute}};
}

sub filter_by_attribute {
  my ($self, $attributes, $filter) = @_;

  my $index = $self->{_index}{attribute};
  my $result;

  for my $att_name (keys %$attributes) {
    my @result;
    my @matching_values;
    my @search_terms = ref($attributes->{$att_name}) && ref($attributes->{$att_name}) eq 'ARRAY'
                           ? @{$attributes->{$att_name}} : $attributes->{$att_name};
    my @regexp_terms;
    my @terms;

    for my $v (@search_terms) {
      if (my $regexp = $self->glob_match($v)) {
	@regexp_terms      = keys %{$index->{lc $att_name}} unless @regexp_terms;
	push @terms,grep {/^$v$/i} @regexp_terms;
      } else {
	push @terms,lc $v;
      }
    }

    for my $v (@terms) {
      push @result,keys %{$index->{lc $att_name}{$v}};
    }

    $result ||= $self->update_filter($filter,\@result);
  }

  $result;
}

sub filter_by_location {
  my ($self, $seq_id, $start, $end, $strand, $range_type, $filter) = @_;
  $strand ||= 0;

  my $index = $self->{_index}{location}{lc $seq_id};
  my @bins;

  if (!defined $start or !defined $end or $range_type eq 'contained_in') {
    @bins = sort {$a<=>$b} keys %{$index};
    $start = $bins[0]  * BINSIZE  unless defined $start;
    $end   = (($bins[-1] + 1) * BINSIZE) - 1 unless defined $end;
  }
  my %seenit;
  my $bin_min       = int $start/BINSIZE;
  my $bin_max       = int $end/BINSIZE;
  my @bins_in_range = $range_type eq 'contained_in' ? ($bins[0]..$bin_min,$bin_max..$bins[-1])
                                                    : ($bin_min..$bin_max);

  my @results;
  for my $bin (@bins_in_range) {
    next unless exists $index->{$bin};
    my @found = keys %{$index->{$bin}};
    for my $f (@found) {
      next if $seenit{$f}++;
      my $feature = $self->_fetch($f) or next;
      next if $strand && $feature->strand != $strand;

      if ($range_type eq 'overlaps') {
	next unless $feature->end >= $start && $feature->start <= $end;
      }
      elsif ($range_type eq 'contains') {
	next unless $feature->start >= $start && $feature->end <= $end;
      }
      elsif ($range_type eq 'contained_in') {
	next unless $feature->start <= $start && $feature->end >= $end;
      }

      push @results,$f;
    }
  }
  $self->update_filter($filter,\@results);
}


sub filter_by_name {
  my ($self, $name, $allow_aliases, $filter) = @_;

  my $index = $self->{_index}{name};

  my @names_to_fetch;
  if (my $regexp = $self->glob_match($name)) {
    @names_to_fetch = grep {/^$regexp$/i} keys %{$index};
  } else {
    @names_to_fetch = lc $name;
  }

  my @results;
  for my $n (@names_to_fetch) {
    if ($allow_aliases) {
      push @results,keys %{$index->{$n}};
    } else {
      push @results,grep {$index->{$n}{$_} == 1} keys %{$index->{$n}};
    }
  }
  $self->update_filter($filter,\@results);
}

sub glob_match {
  my ($self, $term) = @_;
  return unless $term =~ /(?:^|[^\\])[*?]/;
  $term =~ s/(^|[^\\])([+\[\]^{}\$|\(\).])/$1\\$2/g;
  $term =~ s/(^|[^\\])\*/$1.*/g;
  $term =~ s/(^|[^\\])\?/$1./g;
  return $term;
}


sub update_filter {
  my ($self, $filter, $results) = @_;
  return unless @$results;

  if (%$filter) {
    my @filtered = grep {$filter->{$_}} @$results;
    %$filter     = map {$_=>1} @filtered;
  } else {
    %$filter     = map {$_=>1} @$results;
  }

}

sub _search_attributes {
  my ($self, $search_string, $attribute_array, $limit) = @_;

  $search_string =~ tr/*?//d;

  my @words = map {quotemeta($_)} $search_string =~ /(\w+)/g;
  my $search = join '|',@words;

  my (%results,%notes);

  my $index  = $self->{_index}{attribute};
  for my $tag (@$attribute_array) {
    my $attributes = $index->{lc $tag};
    for my $value (keys %{$attributes}) {
      next unless $value =~ /$search/i;
      my @ids = keys %{$attributes->{$value}};
      for my $w (@words) {
	my @hits = $value =~ /($w)/ig or next;
	$results{$_} += @hits foreach @ids;
      }
      $notes{$_} .= "$value " foreach @ids;
    }
  }

  my @results;
  for my $id (keys %results) {
    my $hits = $results{$id};
    my $note = $notes{$id};
    $note =~ s/\s+$//;
    my $relevance = 10 * $hits;
    my $feature   = $self->fetch($id);
    my $name      = $feature->display_name or next;
    my $type      = $feature->type;
    push @results,[$name,$note,$relevance,$type,$id];
  }

  return @results;
}

=head2 types

 Title   : types
 Usage   : @type_list = $db->types
 Function: Get all the types in the database
 Returns : array of Bio::DB::GFF::Typename objects (arrayref in scalar context)
 Args    : none
 Status  : public

=cut

sub types {
  my $self = shift;
  eval "require Bio::DB::GFF::Typename" unless Bio::DB::GFF::Typename->can('new');
  my @types;
  for my $primary_tag ( keys %{$$self{_index}{type}} ) {
    for my $source_tag ( keys %{$$self{_index}{type}{$primary_tag}} ) {
	push @types, Bio::DB::GFF::Typename->new($primary_tag,$source_tag);
    }
  }
  return @types;
}

# this is ugly
sub _insert_sequence {
  my ($self, $seqid, $seq, $offset) = @_;
  my $dna_fh = $self->private_fasta_file or return;
  if ($offset == 0) { # start of the sequence
    print $dna_fh ">$seqid\n";
  }
  print $dna_fh $seq,"\n";
}

sub _fetch_sequence {
  my ($self, $seqid, $start, $end) = @_;
  my $db = $self->{fasta_db} or return;
  $db->seq($seqid,$start,$end);
}

sub private_fasta_file {
  my $self = shift;
  return $self->{fasta_fh} if exists $self->{fasta_fh};
  my $dir = tempdir (CLEANUP => 1);
  $self->{fasta_file}   = "$dir/sequence.$$.fasta";
  return $self->{fasta_fh} = IO::File->new($self->{fasta_file},">");
}

# summary support
sub coverage_array {
    my $self = shift;

    my ($seq_name,$start,$end,$types,$bins) = 
	rearrange([['SEQID','SEQ_ID','REF'],'START',['STOP','END'],
		   ['TYPES','TYPE','PRIMARY_TAG'],'BINS'],@_);

    my @features = $self->_features(-seq_id=> $seq_name,
				    -start => $start,
				    -end   => $end,
				    -types => $types);

    my $binsize = ($end-$start+1)/$bins;
    my $report_tag;
    my @coverage_array = (0) x $bins;
    
    for my $f (@features) {
	$report_tag ||= $f->primary_tag;
	my $fs        = $f->start;
	my $fe        = $f->end;
	my $start_bin = int(($fs-$start)/$binsize);
	my $end_bin   = int(($fe-$start)/$binsize);
	$start_bin    = 0       if $start_bin < 0;
	$end_bin      = $bins-1 if $end_bin  >= $bins;
	$coverage_array[$_]++ for ($start_bin..$end_bin);
    }
    return wantarray ? (\@coverage_array,$report_tag) : \@coverage_array;
}

sub _seq_ids {
    my $self = shift;

    if (my $fa = $self->{fasta_db}) {
	if (my @s = eval {$fa->ids}) {
	    return @s;
	}
    } 
    
    my $l    = $self->{_index}{location} or return;
    return keys %$l;
}

package Bio::DB::SeqFeature::Store::memory::Iterator;

sub new {
  my ($class, $store, $ids) = @_;
  return bless {store => $store,
		ids   => $ids},ref($class) || $class;
}

sub next_seq {
  my $self  = shift;
  my $store = $self->{store} or return;
  my $id    = shift @{$self->{ids}};
  defined $id or return;
  return $store->fetch($id);
}

1;

__END__

=head1 BUGS

This is an early version, so there are certainly some bugs. Please
use the BioPerl bug tracking system to report bugs.

=head1 SEE ALSO

L<bioperl>,
L<Bio::DB::SeqFeature>,
L<Bio::DB::SeqFeature::Store>,
L<Bio::DB::SeqFeature::GFF3Loader>,
L<Bio::DB::SeqFeature::Segment>,
L<Bio::DB::SeqFeature::Store::berkeleydb>,
L<Bio::DB::SeqFeature::Store::DBI::mysql>

=head1 AUTHOR

Lincoln Stein E<lt>lstein@cshl.orgE<gt>.

Copyright (c) 2006 Cold Spring Harbor Laboratory.

This library is free software; you can redistribute it and/or modify
it under the same terms as Perl itself.

=cut