/**
* Processes the current stem with the 1st step
* of the Porter algorithm.
*
* @return void
* @author John Anderson
* @see http://snowball.tartarus.org/algorithms/english/stemmer.html
*/
protected function step1()
{
// a:
$this->currentStem = $this->performOnLongestSuffix($this->currentStem, array("sses" => function ($word) {
return preg_replace("/sses\$/", 'ss', $word);
}, "ied" => function ($word) {
if (strlen($word) > 4) {
return preg_replace("/ied\$/", 'i', $word);
} else {
return preg_replace("/ied\$/", 'ie', $word);
}
}, "ies" => function ($word) {
if (strlen($word) > 4) {
return preg_replace("/ies\$/", 'i', $word);
} else {
return preg_replace("/ies\$/", 'ie', $word);
}
}, "s" => function ($word) {
if (strlen($word) > 2 && preg_match('/[aeiouy].+s$/', substr($word, 0, strlen($word) - 1)) < 1) {
return preg_replace("/s\$/", '', $word);
} else {
return $word;
}
}, "us" => function ($word) {
return $word;
}, "ss" => function ($word) {
return $word;
}));
//Exceptional forms
$exceptions = array('inning', 'outing', 'canning', 'herring', 'earring', 'proceed', 'exceed', 'succeed');
if (isset($exceptions[$this->currentStem])) {
return $exceptions[$this->currentStem];
}
// b:
$this->currentStem = $this->performOnLongestSuffix($this->currentStem, array("eed" => function ($word) {
if (strstr(Stemmer::getR1($word), 'eed')) {
return preg_replace("/eed\$/", 'ee', $word);
}
}, "eedly" => function ($word) {
if (strstr(Stemmer::getR1($word), 'eedly')) {
return preg_replace("/eedly\$/", 'ee', $word);
}
}, "ed" => function ($word) {
$rest = substr($word, 0, strlen($word) - 2);
if (preg_match('/[aeiouy]/', $rest) > 0) {
$word = $rest;
$newSuffix = substr($word, -2, 2);
$endings = array('at', 'bl', 'iz');
$doubles = array('bb', 'dd', 'ff', 'gg', 'mm', 'nn', 'pp', 'rr', 'tt');
if (in_array($newSuffix, $endings)) {
$word = $word . 'e';
} else {
if (in_array($newSuffix, $doubles)) {
$word = substr($word, 0, strlen($word) - 1);
} else {
if (Stemmer::isShort($word)) {
$word = $word . 'e';
}
}
}
}
return $word;
}, "edly" => function ($word) {
$rest = substr($word, 0, strlen($word) - 4);
if (preg_match('/[aeiouy]/', $rest) > 0) {
$word = $rest;
$newSuffix = substr($word, -2, 2);
$endings = array('at', 'bl', 'iz');
$doubles = array('bb', 'dd', 'ff', 'gg', 'mm', 'nn', 'pp', 'rr', 'tt');
if (in_array($newSuffix, $endings)) {
$word = $word . 'e';
} else {
if (in_array($newSuffix, $doubles)) {
$word = substr($word, 0, strlen($word) - 1);
} else {
if (Stemmer::isShort($word)) {
$word = $word . 'e';
}
}
}
}
return $word;
}, "ing" => function ($word) {
$rest = substr($word, 0, strlen($word) - 3);
if (preg_match('/[aeiouy]/', $rest) > 0) {
$word = $rest;
$newSuffix = substr($word, -2, 2);
$endings = array('at', 'bl', 'iz');
$doubles = array('bb', 'dd', 'ff', 'gg', 'mm', 'nn', 'pp', 'rr', 'tt');
if (in_array($newSuffix, $endings)) {
$word = $word . 'e';
} else {
if (in_array($newSuffix, $doubles)) {
$word = substr($word, 0, strlen($word) - 1);
} else {
if (Stemmer::isShort($word)) {
$word = $word . 'e';
}
}
}
}
return $word;
}, "ingly" => function ($word) {
$rest = substr($word, 0, strlen($word) - 5);
if (preg_match('/[aeiouy]/', $rest) > 0) {
$word = $rest;
$newSuffix = substr($word, -2, 2);
$endings = array('at', 'bl', 'iz');
$doubles = array('bb', 'dd', 'ff', 'gg', 'mm', 'nn', 'pp', 'rr', 'tt');
if (in_array($newSuffix, $endings)) {
$word = $word . 'e';
} else {
if (in_array($newSuffix, $doubles)) {
$word = substr($word, 0, strlen($word) - 1);
} else {
if (Stemmer::isShort($word)) {
$word = $word . 'e';
}
}
}
}
return $word;
}));
// c:
$this->currentStem = preg_replace('/([bcdfghjklmnpqrstvwxz])[yY]$/', '$1i', $this->currentStem);
}
