<?php

declare(strict_types=1);

/*
 * This file is part of the TYPO3 CMS project.
 *
 * It is free software; you can redistribute it and/or modify it under
 * the terms of the GNU General Public License, either version 2
 * of the License, or any later version.
 *
 * For the full copyright and license information, please read the
 * LICENSE.txt file that was distributed with this source code.
 *
 * The TYPO3 project - inspiring people to share!
 */

namespace TYPO3\CMS\Backend\ViewHelpers\TypoScript;

use TYPO3\CMS\Core\Utility\DiffUtility;
use TYPO3\CMS\Core\Utility\GeneralUtility;
use TYPO3Fluid\Fluid\Core\ViewHelper\AbstractViewHelper;

/**
 * ViewHelper to runs two strings through 'FineDiff' on word level.
 *
 * ```
 *   <backend:typoScript.fineDiff from="{someTextChunkBefore}" to="{someTextChunkAfter}" />
 * ```
 *
 * @see https://docs.typo3.org/permalink/t3viewhelper:typo3-backend-typoscript-finediff
 * @internal This experimental ViewHelper is not part of TYPO3 Core API and may change or vanish any time.
 */
final class FineDiffViewHelper extends AbstractViewHelper
{
    public function initializeArguments(): void
    {
        parent::initializeArguments();
        $this->registerArgument('from', 'string', 'Source string', true);
        $this->registerArgument('to', 'string', 'Target string', true);
    }

    public function render(): string
    {
        $diffUtility = GeneralUtility::makeInstance(DiffUtility::class);
        return $diffUtility->diff($this->arguments['from'], $this->arguments['to']);
    }
}
