<?php

/**
 * @package     MokoJoomBackup
 * @subpackage  com_mokojoombackup
 * @author      Moko Consulting <hello@mokoconsulting.tech>
 * @copyright   Copyright (C) 2026 Moko Consulting. All rights reserved.
 * @license     GNU General Public License version 3 or later; see LICENSE
 *
 * AJAX controller for step-based backups.
 * Handles init and step requests from the admin UI JavaScript.
 */

namespace Joomla\Component\MokoJoomBackup\Administrator\Controller;

defined('_JEXEC') or die;

use Joomla\CMS\MVC\Controller\BaseController;
use Joomla\CMS\Session\Session;
use Joomla\Component\MokoJoomBackup\Administrator\Engine\SteppedBackupEngine;

class AjaxController extends BaseController
{
	/**
	 * Initialize a new stepped backup.
	 * POST: task=ajax.init&profile_id=1&description=...
	 */
	public function init(): void
	{
		if (!Session::checkToken('get') && !Session::checkToken('post')) {
			$this->sendJson(['error' => true, 'message' => 'Invalid token']);

			return;
		}

		$profileId   = $this->input->getInt('profile_id', 1);
		$description = $this->input->getString('description', '');

		$engine = new SteppedBackupEngine();
		$result = $engine->init($profileId, $description, 'backend');

		$this->sendJson($result);
	}

	/**
	 * Run the next step of a backup session.
	 * POST: task=ajax.step&session_id=mb_...
	 */
	public function step(): void
	{
		if (!Session::checkToken('get') && !Session::checkToken('post')) {
			$this->sendJson(['error' => true, 'message' => 'Invalid token']);

			return;
		}

		$sessionId = $this->input->getString('session_id', '');

		if (empty($sessionId)) {
			$this->sendJson(['error' => true, 'message' => 'Missing session_id']);

			return;
		}

		$engine = new SteppedBackupEngine();
		$result = $engine->runStep($sessionId);

		$this->sendJson($result);
	}

	/**
	 * Browse server directories for the folder picker field.
	 * POST: task=ajax.browseDir&path=/some/path
	 */
	public function browseDir(): void
	{
		if (!Session::checkToken('get') && !Session::checkToken('post')) {
			$this->sendJson(['error' => true, 'message' => 'Invalid token']);

			return;
		}

		$requestPath = $this->input->getString('path', JPATH_ROOT);
		$path = realpath($requestPath) ?: $requestPath;

		// Security: restrict browsing to site root and current user's home
		$jRoot   = realpath(JPATH_ROOT);
		$homeDir = getenv('HOME') ?: (getenv('USERPROFILE') ?: '');
		$allowed = false;

		if ($jRoot !== false && strpos($path, $jRoot) === 0) {
			$allowed = true;
		} elseif ($homeDir !== '' && strpos($path, $homeDir) === 0) {
			$allowed = true;
		}

		if (!$allowed) {
			$this->sendJson(['error' => true, 'message' => 'Access denied: path outside allowed directories']);
			return;
		}

		if (!is_dir($path)) {
			$this->sendJson(['error' => true, 'message' => 'Directory not found: ' . $path]);

			return;
		}

		// Security: only allow browsing within JPATH_ROOT or parent directories
		// that could contain a backup folder (e.g., /home/user/backups)
		$dirs   = [];
		$handle = @opendir($path);

		if ($handle) {
			while (($entry = readdir($handle)) !== false) {
				if ($entry === '.' || $entry === '..') {
					continue;
				}

				$fullPath = $path . '/' . $entry;

				if (is_dir($fullPath) && $entry[0] !== '.') {
					$dirs[] = [
						'name' => $entry,
						'path' => $fullPath,
					];
				}
			}

			closedir($handle);
		}

		usort($dirs, fn($a, $b) => strcasecmp($a['name'], $b['name']));

		$parent = dirname($path);

		$this->sendJson([
			'error'   => false,
			'current' => $path,
			'parent'  => ($parent !== $path) ? $parent : null,
			'dirs'    => $dirs,
		]);
	}

	/**
	 * Load and return the log file contents for a backup record.
	 * POST: task=ajax.viewLog&id=123
	 */
	public function viewLog(): void
	{
		if (!Session::checkToken('get') && !Session::checkToken('post')) {
			$this->sendJson(['error' => true, 'message' => 'Invalid token']);

			return;
		}

		$id = $this->input->getInt('id', 0);

		if (!$id) {
			$this->sendJson(['error' => true, 'message' => 'Missing record ID']);

			return;
		}

		$db    = \Joomla\CMS\Factory::getDbo();
		$query = $db->getQuery(true)
			->select($db->quoteName(['absolute_path', 'log']))
			->from($db->quoteName('#__mokojoombackup_records'))
			->where($db->quoteName('id') . ' = ' . $id);
		$db->setQuery($query);
		$record = $db->loadObject();

		if (!$record) {
			$this->sendJson(['error' => true, 'message' => 'Record not found']);

			return;
		}

		// Try to load log from file alongside the archive
		$logPath = preg_replace('/\.(zip|tar\.gz)$/i', '.log', $record->absolute_path);
		$logContent = '';

		if (is_file($logPath)) {
			$logContent = file_get_contents($logPath);
		} elseif (!empty($record->log)) {
			// Fall back to database-stored log
			$logContent = $record->log;
		}

		$this->sendJson([
			'error'   => false,
			'log'     => $logContent ?: '(no log available)',
			'source'  => is_file($logPath) ? 'file' : 'database',
		]);
	}

	/**
	 * Check directory existence, writability and permissions.
	 * POST: task=ajax.checkDir&path=/some/path
	 */
	public function checkDir(): void
	{
		if (!Session::checkToken('get') && !Session::checkToken('post')) {
			$this->sendJson(['error' => true, 'message' => 'Invalid token']);

			return;
		}

		$rawPath = trim($this->input->getString('path', ''));

		if ($rawPath === '') {
			$this->sendJson(['error' => true, 'message' => 'No path provided']);

			return;
		}

		// Resolve [DEFAULT_DIR] placeholder
		$defaultDir = JPATH_ADMINISTRATOR . '/components/com_mokojoombackup/backups';
		$resolved   = str_replace('[DEFAULT_DIR]', $defaultDir, $rawPath);

		// Resolve relative paths from JPATH_ROOT
		if ($resolved !== '' && $resolved[0] !== '/' && !preg_match('#^[A-Za-z]:[/\\\\]#', $resolved)) {
			$resolved = JPATH_ROOT . '/' . $resolved;
		}

		// Skip check if unresolved placeholders remain
		if (preg_match('/\[.+\]/', $resolved)) {
			$this->sendJson([
				'error'       => false,
				'exists'      => null,
				'writable'    => null,
				'resolved'    => $resolved,
				'placeholder' => true,
			]);

			return;
		}

		$exists   = is_dir($resolved);
		$writable = $exists && is_writable($resolved);

		$this->sendJson([
			'error'       => false,
			'exists'      => $exists,
			'writable'    => $writable,
			'resolved'    => $resolved,
			'placeholder' => false,
		]);
	}

	/**
	 * Send a JSON response and close the application.
	 */
	private function sendJson(array $data): void
	{
		$app = $this->app;
		$app->setHeader('Content-Type', 'application/json; charset=utf-8');
		$app->setHeader('Cache-Control', 'no-cache, no-store, must-revalidate');
		$app->sendHeaders();

		echo json_encode($data);

		$app->close();
	}
}