<?php /** @noinspection PhpIllegalPsrClassPathInspection */

namespace WPDRMS\Utils;

if ( !defined('ABSPATH') ) {
	die('-1');
}

class Suggest {
	/**
	 * Returns a list of keywords most similar from $source_arr array to $string string
	 *
	 * @param array  $source_arr
	 * @param string $s
	 * @param int    $count
	 * @param int    $threshold
	 * @param bool   $lowercase
	 * @return array
	 */
	public static function getSimilarText(
		array $source_arr,
		string $s,
		int $count = 1,
		int $threshold = 34,
		bool $lowercase = true
	): array {
		$matches = array();
		if ( count($source_arr) <= 0 || $s === '' ) {
			return $matches;
		}
		$count      = min($count, 100);
		$i          = 0;
		$source_arr = array_unique($source_arr);
		foreach ( $source_arr as $word ) {
			// Tested with an array of 500 000 items, ~1 sec execution time
			similar_text(MB::strtolower($word), MB::strtolower($s), $perc);
			$matches[] = array(
				'r' => $perc,
				'w' => $word,
			);
			++$i;
			if ( ( $i % 100 ) === 0 ) {
				$keys = array_column($matches, 'r');
				array_multisort($keys, SORT_DESC, $matches);
				$matches = array_slice($matches, 0, $count);
			}
		}
		$keys = array_column($matches, 'r');
		array_multisort($keys, SORT_DESC, $matches);
		$matches = array_slice($matches, 0, $count);
		foreach ( $matches as $k => &$match ) {
			if ( $match['r'] < $threshold ) {
				unset($matches[ $k ]);
			} elseif ( $lowercase ) {
				$match['w'] = MB::strtolower($match['w']);
			}
		}
		return array_column($matches, 'w');
	}
}