<?php
namespace WapplerSystems\Meilisearch\FieldProcessor;

/***************************************************************
 *  Copyright notice
 *
 *  (c) 2013-2015 Steffen Ritter <steffen.ritter@typo3.org>
 *  All rights reserved
 *
 *  This script is part of the TYPO3 project. The TYPO3 project is
 *  free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  The GNU General Public License can be found at
 *  http://www.gnu.org/copyleft/gpl.html.
 *
 *  This script 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 General Public License for more details.
 *
 *  This copyright notice MUST APPEAR in all copies of the script!
 ***************************************************************/
use WapplerSystems\Meilisearch\System\Records\SystemCategory\SystemCategoryRepository;
use TYPO3\CMS\Core\Utility\GeneralUtility;

/**
 * This Processor takes a UID of sys_category, and resolves its rootline in meilisearch notation.
 *
 * Format of this field corresponds to http://wiki.apache.org/meilisearch/HierarchicalFaceting
 *
 * Let's say we have a category with uid 111 which is a sub category like shown in this tree:
 *
 * 1
 * |-10
 *   |-100
 *     |-111
 *
 * then we get a rootline 1/10/100/111
 *
 * In Meilisearch hierarchy notation, we get
 *
 * 0-1
 * 1-1/10
 * 2-1/10/100
 * 3-1/10/100/11
 *
 * which is finally saved in a multi-value field.
 *
 * @author Steffen Ritter <steffen.ritter@typo3.org>
 */
class CategoryUidToHierarchy extends AbstractHierarchyProcessor implements FieldProcessor
{
    /**
     * @var SystemCategoryRepository
     */
    protected $systemCategoryRepository;

    /**
     * CategoryUidToHierarchy constructor.
     *
     * @param SystemCategoryRepository|null $systemCategoryRepository
     */
    public function __construct(SystemCategoryRepository $systemCategoryRepository = null)
    {
        $this->systemCategoryRepository = $systemCategoryRepository ?? GeneralUtility::makeInstance(SystemCategoryRepository::class);
    }

    /**
     * Expects a uid ID of a category. Returns a Meilisearch hierarchy notation for the
     * rootline of the category ID.
     *
     * @param array $values Array of values, an array because of multivalued fields
     * @return array Modified array of values
     */
    public function process(array $values)
    {
        $results = [];

        foreach ($values as $value) {
            $results = array_merge($results,
                $this->getMeilisearchRootlineForCategoryId($value));
        }

        return $results;
    }

    /**
     * Returns a Meilisearch hierarchy notation string for rootline of given category uid.
     *
     * @param int $categoryId Category ID to get a rootline as Meilisearch hierarchy for
     * @return array Rootline as Meilisearch hierarchy array
     */
    protected function getMeilisearchRootlineForCategoryId($categoryId)
    {
        $categoryIdRootline = $this->buildCategoryIdRootline($categoryId);
        $meilisearchRootline = $this->buildMeilisearchHierarchyFromIdRootline($categoryIdRootline);

        return $meilisearchRootline;
    }

    /**
     * Builds a category's rootline of parent category Ids
     *
     * @param int $uid The category ID to build the rootline for
     * @return array Category ID rootline as array
     */
    protected function buildCategoryIdRootline($uid)
    {
        $rootlineIds = [];
        $parentCategory = intval($uid);

        while ($parentCategory !== 0) {
            $rootlineIds[] = $parentCategory;
            $childCategory = $this->systemCategoryRepository->findOneByUid($parentCategory);
            if ($childCategory === null) {
                $parentCategory = 0;
            } else {
                $parentCategory = intval($childCategory['parent']);
            }
        }
        krsort($rootlineIds);

        return array_values($rootlineIds);
    }
}