<?php
namespace WapplerSystems\Meilisearch;

/***************************************************************
 *  Copyright notice
 *
 *  (c) 2011-2015 Ingo Renner <ingo@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\Configuration\TypoScriptConfiguration;
use WapplerSystems\Meilisearch\System\ContentObject\ContentObjectService;
use WapplerSystems\Meilisearch\System\Meilisearch\Document\Document;
use TYPO3\CMS\Core\Utility\GeneralUtility;

/**
 * Additional fields indexer.
 *
 * @todo Move this to an Index Queue frontend helper
 *
 * Adds page document fields as configured in
 * plugin.tx_meilisearch.index.additionalFields.
 *
 * @author Ingo Renner <ingo@typo3.org>
 */
class AdditionalFieldsIndexer implements SubstitutePageIndexer
{

    /**
     * @var TypoScriptConfiguration
     */
    protected $configuration;

    /**
     * @var array
     */
    protected $additionalIndexingFields = [];

    /**
     * @var array
     */
    protected $additionalFieldNames = [];

    /**
     * @var ContentObjectService
     */
    protected $contentObjectService = null;

    /**
     * @param TypoScriptConfiguration $configuration
     * @param ContentObjectService $contentObjectService
     */
    public function __construct(TypoScriptConfiguration $configuration = null, ContentObjectService $contentObjectService = null)
    {
        $this->configuration = $configuration === null ? Util::getMeilisearchConfiguration() : $configuration;
        $this->additionalIndexingFields = $this->configuration->getIndexAdditionalFieldsConfiguration();
        $this->additionalFieldNames = $this->configuration->getIndexMappedAdditionalFieldNames();
        $this->contentObjectService = $contentObjectService === null ? GeneralUtility::makeInstance(ContentObjectService::class) : $contentObjectService;
    }

    /**
     * Returns a substitute document for the currently being indexed page.
     *
     * Uses the original document and adds fields as defined in
     * plugin.tx_meilisearch.index.additionalFields.
     *
     * @param Document $pageDocument The original page document.
     * @return Document A Meilisearch Document object that replace the default page document
     */
    public function getPageDocument(Document $pageDocument)
    {
        $substitutePageDocument = clone $pageDocument;
        $additionalFields = $this->getAdditionalFields();

        foreach ($additionalFields as $fieldName => $fieldValue) {
            if (!isset($pageDocument->{$fieldName})) {
                // making sure we only _add_ new fields
                $substitutePageDocument->setField($fieldName, $fieldValue);
            }
        }

        return $substitutePageDocument;
    }

    /**
     * Gets the additional fields as an array mapping field names to values.
     *
     * @return array An array mapping additional field names to their values.
     */
    protected function getAdditionalFields()
    {
        $additionalFields = [];

        foreach ($this->additionalFieldNames as $additionalFieldName) {
            $additionalFields[$additionalFieldName] = $this->getFieldValue($additionalFieldName);
        }

        return $additionalFields;
    }

    /**
     * Uses the page's cObj instance to resolve the additional field's value.
     *
     * @param string $fieldName The name of the field to get.
     * @return string The field's value.
     */
    protected function getFieldValue($fieldName)
    {
        return $this->contentObjectService->renderSingleContentObjectByArrayAndKey($this->additionalIndexingFields, $fieldName);
    }
}