Differential D18484 Diff 44406 src/applications/search/ngrams/PhabricatorNgramEngine.php

Changeset View

Standalone View

				<?php

				final class PhabricatorNgramEngine extends Phobject {

				public function tokenizeString($value) {
				$value = trim($value, ' ');
				$value = preg_split('/ +/', $value);
				return $value;
				}

				public function getNgramsFromString($value, $mode) {
				$tokens = $this->tokenizeString($value);

				$ngrams = array();
				foreach ($tokens as $token) {
				$token = phutil_utf8_strtolower($token);

				switch ($mode) {
				case 'query':
				break;
				case 'index':
				$token = ' '.$token.' ';
				break;
				case 'prefix':
				$token = ' '.$token;
				break;
				}

				$len = (strlen($token) - 2);
				for ($ii = 0; $ii < $len; $ii++) {
				$ngram = substr($token, $ii, 3);
				$ngrams[$ngram] = $ngram;
				}
				}

				ksort($ngrams);

				return array_keys($ngrams);
				}

				}