<?php
/**
 * @package   admintools
 * @copyright Copyright (c)2010-2025 Nicholas K. Dionysopoulos / Akeeba Ltd
 * @license   GNU General Public License version 3, or later
 */

namespace Akeeba\Component\AdminTools\Administrator\Scanner\Diff;

/**
 * =====================================================================================================================
 * Software copyright notice
 *
 * This software has been modified by Akeeba Ltd to make it compatible with newer versions of PHP, address minor issues,
 * implement namespaces and other minor modifications of a similar nature. The following copyright notice accompanies
 * the original software; we are required to copy it verbatim in our modified copy. Please do keep in mind that this is
 * NOT the original software. It's a modified copy. Thank you.
 * =====================================================================================================================
 *
 * Diff
 *
 * A comprehensive library for generating differences between two strings
 * in multiple formats (unified, side by side HTML etc)
 *
 * PHP version 5
 *
 * Copyright (c) 2009 Chris Boulton <[email protected]>
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *  - Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 *  - Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 *  - Neither the name of the Chris Boulton nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 * @package       Diff
 * @author        Chris Boulton <[email protected]>
 * @copyright (c) 2009 Chris Boulton
 * @license       New BSD License http://www.opensource.org/licenses/bsd-license.php
 * @version       1.1
 * @link          http://github.com/chrisboulton/php-diff
 */

defined('_JEXEC') or die;

class RendererTextUnified extends RendererAbstract

{
	/**
	 * Render and return a unified diff.
	 *
	 * @return string The unified diff.
	 */
	public function render()
	{
		$diff    = '';
		$opCodes = $this->diff->getGroupedOpcodes();
		foreach ($opCodes as $group)
		{
			$lastItem = (is_array($group) || $group instanceof \Countable ? count($group) : 0) - 1;
			$i1       = $group[0][1];
			$i2       = $group[$lastItem][2];
			$j1       = $group[0][3];
			$j2       = $group[$lastItem][4];

			if ($i1 == 0 && $i2 == 0)
			{
				$i1 = -1;
				$i2 = -1;
			}

			$diff .= '@@ -' . ($i1 + 1) . ',' . ($i2 - $i1) . ' +' . ($j1 + 1) . ',' . ($j2 - $j1) . " @@\n";
			foreach ($group as $code)
			{
				[$tag, $i1, $i2, $j1, $j2] = $code;
				if ($tag == 'equal')
				{
					$diff .= ' ' . implode("\n ", $this->diff->GetA($i1, $i2)) . "\n";
				}
				else
				{
					if ($tag == 'replace' || $tag == 'delete')
					{
						$diff .= '-' . implode("\n-", $this->diff->GetA($i1, $i2)) . "\n";
					}

					if ($tag == 'replace' || $tag == 'insert')
					{
						$diff .= '+' . implode("\n+", $this->diff->GetB($j1, $j2)) . "\n";
					}
				}
			}
		}

		return $diff;
	}
}