<?php /** * Created by PhpStorm. * User: turgutsaricam * Date: 10/11/2019 * Time: 09:11 * * @since 1.9.0 */ namespace WPCCrawler\Objects\Chunk\LengthStrategy; abstract class AbstractLengthStrategy { /** @var AbstractLengthStrategy[] */ protected static $instances = []; /** * Get the instance * * @return static * @since 1.9.0 */ abstract public static function getInstance(); /** * Get length of a text * * @param string $text Text whose length is wanted * @return int The length of the text * @since 1.9.0 */ abstract public function getLengthFor(string $text): int; /** * Get byte offsets that will be used to cut the text to satisfy maximum length constraint * * @param string $text Text that will be cut * @param int $maxLength Maximum length that should be satisfied by offsets. In other words, when the text * is divided into parts using the resultant offsets, each part can only have this * number of items in it. * @param int $textLength Length of $text, calculated by using {@link getLengthFor()}. * @param int $minOffsetCount Minimum number of offsets that must be returned by this method. * @return int[] An array of byte locations indicating the cut locations for the given text such that each part * created with cuts satisfy $maxLength constraint. * @since 1.9.0 */ abstract public function getByteOffsetsForCuts(string $text, int $maxLength, int $textLength, int $minOffsetCount): array; /* * PROTECTED METHODS */ /** * Validate offsets. If the offsets are not valid, $offsets array is set to an empty array. * * @param int[] $offsets An integer array storing the byte offsets of cut locations * @param int $minOffsetCount Minimum number of offsets that there should be * @since 1.9.0 */ protected function validateByteOffsets(array &$offsets, int $minOffsetCount): void { // If not enough number of offsets is found, then invalidate the offsets. We need at least a // certain number of offsets so that the text will be divided into parts satisfying the max // length constraint. If this condition is not met, invalidate the offsets so that a more // detailed search is performed to find offsets that will satisfy the maximum length constraint. if (sizeof($offsets) < $minOffsetCount) { $offsets = []; } } }