<?php
# Copyright (C) 2006-2010 Tobias Leupold <tobias.leupold@web.de>
#
# This file is part of the b8 package
#
# This program is free software; you can redistribute it and/or modify it
# under the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation in version 2.1 of the License.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
# or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
# License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with this program; if not, write to the Free Software Foundation,
# Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
/**
* Copyright (C) 2006-2010 Tobias Leupold <tobias.leupold@web.de>
*
* @license LGPL
* @access public
* @package b8
* @author Tobias Leupold
*/
class b8_degenerator_default
{
public $degenerates = array();
/**
* Generates a list of "degenerated" words for a list of words.
*
* @access public
* @param array $tokens
* @return array An array containing an array of degenerated tokens for each token
*/
public function degenerate(array $words)
{
$degenerates = array();
foreach($words as $word)
$degenerates[$word] = $this->_degenerate_word($word);
return $degenerates;
}
/**
* If the original word is not found in the database then
* we build "degenerated" versions of the word to lookup.
*
* @access private
* @param string $word
* @return array An array of degenerated words
*/
protected function _degenerate_word($word)
{
# Check for any stored words so the process doesn't have to repeat
if(isset($this->degenerates[$word]) === TRUE)
return $this->degenerates[$word];
$degenerate = array();
# Add different version of upper and lower case and ucfirst
array_push($degenerate, strtolower($word));
array_push($degenerate, strtoupper($word));
array_push($degenerate, ucfirst($word));
# Degenerate all versions
foreach($degenerate as $alt_word) {
# Look for stuff like !!! and ???
if(preg_match('/[!?]$/', $alt_word) > 0) {
# Add versions with different !s and ?s
if(preg_match('/[!?]{2,}$/', $alt_word) > 0) {
$tmp = preg_replace('/([!?])+$/', '$1', $alt_word);
array_push($degenerate, $tmp);
}
$tmp = preg_replace('/([!?])+$/', '', $alt_word);
array_push($degenerate, $tmp);
}
# Look for ... at the end of the word
$alt_word_int = $alt_word;
while(preg_match('/[\.]$/', $alt_word_int) > 0) {
$alt_word_int = substr($alt_word_int, 0, strlen($alt_word_int) - 1);
array_push($degenerate, $alt_word_int);
}
}
# Some degenerates are the same as the original word. These don't have
# to be fetched, so we create a new array with only new tokens
$real_degenerate = array();
foreach($degenerate as $deg_word) {
if($word != $deg_word)
array_push($real_degenerate, $deg_word);
}
# Store the list of degenerates for the token
$this->degenerates[$word] = $real_degenerate;
return $real_degenerate;
}
}
?>
