package Set::IntervalTree;

use 5.006001;
use strict;
use warnings;
use Carp;

require Exporter;
use AutoLoader;

our @ISA = qw(Exporter);

# Items to export into callers namespace by default. Note: do not export
# names by default without a very good reason. Use EXPORT_OK instead.
# Do not simply export all your public functions/methods/constants.

# This allows declaration	use Set::IntervalTree ':all';
# If you do not need this, moving things directly into @EXPORT or @EXPORT_OK
# will save memory.
our %EXPORT_TAGS = ( 'all' => [ qw(
	
) ] );

our @EXPORT_OK = ( @{ $EXPORT_TAGS{'all'} } );

our @EXPORT = qw(
	
);

our $VERSION = '0.10';

sub AUTOLOAD {
    # This AUTOLOAD is used to 'autoload' constants from the constant()
    # XS function.

    my $constname;
    our $AUTOLOAD;
    ($constname = $AUTOLOAD) =~ s/.*:://;
    croak "&Set::IntervalTree::constant not defined!" if $constname eq 'constant';
    my ($error, $val) = constant($constname);
    if ($error) { croak $error; }
    {
	no strict 'refs';
	# Fixed between 5.005_53 and 5.005_61
#XXX	if ($] >= 5.00561) {
#XXX	    *$AUTOLOAD = sub () { $val };
#XXX	}
#XXX	else {
	    *$AUTOLOAD = sub { $val };
#XXX	}
    }
    goto &$AUTOLOAD;
}

require XSLoader;
XSLoader::load('Set::IntervalTree', $VERSION);

# Preloaded methods go here.

# Autoload methods go after =cut, and are processed by the autosplit program.

1;
__END__
# Below is stub documentation for your module. You'd better edit it!

=head1 NAME

Set::IntervalTree - Perform range-based lookups on sets of ranges.

=head1 SYNOPSIS

  use Set::IntervalTree;
  my $tree = Set::IntervalTree->new;
  $tree->insert("ID1",100,200);
  $tree->insert(2,50,100);
  $tree->insert({id=>3},520,700);
  $tree->insert($some_obj,1000,1100);

  my $results = $tree->fetch(400,800);
  my $window = $tree->fetch_window(100,200);
  print scalar(@$results)." intervals found.\n";

  # remove only items overlapping location 100..200 with values 
  # less than 100;
  my $removed = $tree->remove(100,200 sub {
    my ($item, $low, $high) = @_;
    return $item < 100;
  });

=head1 DESCRIPTION

Set::IntervalTree uses Interval Trees to store and efficiently 
look up ranges using a range-based lookup.

All intervals are half-open, i.e. [1,3), [2,6), etc.

=head1 EXPORTS

Nothing.

=head1 METHODS

my $tree = Set::IntervalTree->new;

  Creates a new interval tree object.

$tree->insert($object, $low, $high);

  Insert a range into the interval tree and associate it with a 
  perl scalar.

  $object can be any perl scalar. This is what will be returned by fetch().
  $low is the lower bound of the range.
  $high is the upper bound of the range.

  Ranges are represented as half-closed integer intervals.

my $results = $tree->fetch($low, $high)

  Return an arrayref of perl objects whose ranges overlap 
  the specified range.

  $low is the lower bound of the region to query.
  $high is the upper bound of the region to query.

my $results = $tree->fetch_window($low, $high)

  Return an arrayref of perl objects whose ranges are completely contained
  witin the specified range.

  $low is the lower bound of the region to query.
  $high is the upper bound of the region to query.

my $nearest_up = $tree->fetch_nearest_up($query)

  Search for the closest interval in upstream that does not contain the query
  and returns the perl object associated with it.

  $query is the position to use for the search

my $nearest_down = $tree->fetch_nearest_down($query)

  Search for the closest interval in downstream that does not contain the query
  and returns the perl object associated with it.

  $query is the position to use for the search

my $removed = $tree->remove($low, $high [, optional \&coderef]);

  Remove items in the tree that overlap the region from $low to $high. 
  A coderef can be passed in as an optional third argument for filtering
  what is removed. The coderef receives the stored item, the low point,
  and the high point as its arguments. If the result value of the coderef
  is true, the item is removed, otherwise the item remains in the tree.

  Returns the list of removed items.

my $removed = $tree->remove_window($low, $high [, optional \&coderef]);

  Remove items in the tree that are contained within the region from $low
  to $high.  A coderef can be passed in as an optional third argument
  for filtering what is removed. The coderef receives the stored item,
  the low point, and the high point as its arguments. If the result
  value of the coderef is true, the item is removed, otherwise the item
  remains in the tree.

  Returns the list of removed items.

=head1 LIMITATIONS

A $tree->print() serialization method might be useful for debugging.

=head1 SEE ALSO

The source code for this module contains a reusable template-based 
C++ header for Interval trees that might be useful.

=head1 AUTHOR

Ben Booth, E<lt>[email protected]<gt>

=head1 COPYRIGHT AND LICENSE

Copyright (C) 2012 by Ben Booth

This library is free software; you can redistribute it and/or modify
it under the same terms as Perl itself, either Perl version 5.10.1 or,
at your option, any later version of Perl 5 you may have available.


=cut