<?php

/**
 * @package     MokoJoomBackup
 * @subpackage  com_mokobackup
 * @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
 */

namespace Joomla\Component\MokoBackup\Administrator\Engine;

defined('_JEXEC') or die;

class FileScanner
{
	private string $rootDir;
	private array $excludeDirs;
	private array $excludeFiles;

	/**
	 * @param   string  $rootDir       Root directory to scan
	 * @param   array   $excludeDirs   Relative directory paths to exclude
	 * @param   array   $excludeFiles  Filename patterns to exclude
	 */
	public function __construct(string $rootDir, array $excludeDirs = [], array $excludeFiles = [])
	{
		$this->rootDir      = rtrim($rootDir, '/\\');
		$this->excludeDirs  = array_map(fn($d) => trim($d, '/\\'), $excludeDirs);
		$this->excludeFiles = $excludeFiles;
	}

	/**
	 * Scan the root directory and return relative file paths.
	 *
	 * @return  string[]  Array of relative file paths
	 */
	public function scan(): array
	{
		$files = [];
		$this->scanDirectory('', $files);

		return $files;
	}

	private function scanDirectory(string $relativePath, array &$files): void
	{
		$fullPath = $this->rootDir . ($relativePath ? '/' . $relativePath : '');

		if (!is_dir($fullPath) || !is_readable($fullPath)) {
			return;
		}

		$handle = opendir($fullPath);

		if ($handle === false) {
			return;
		}

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

			$entryRelative = $relativePath ? $relativePath . '/' . $entry : $entry;
			$entryFull     = $fullPath . '/' . $entry;

			if (is_dir($entryFull)) {
				if (!$this->isDirExcluded($entryRelative)) {
					$this->scanDirectory($entryRelative, $files);
				}
			} elseif (is_file($entryFull)) {
				if (!$this->isFileExcluded($entry)) {
					$files[] = $entryRelative;
				}
			}
		}

		closedir($handle);
	}

	private function isDirExcluded(string $relativePath): bool
	{
		$normalized = str_replace('\\', '/', $relativePath);

		foreach ($this->excludeDirs as $excluded) {
			if ($normalized === $excluded || str_starts_with($normalized, $excluded . '/')) {
				return true;
			}
		}

		// Always exclude .git
		if (basename($relativePath) === '.git') {
			return true;
		}

		return false;
	}

	private function isFileExcluded(string $filename): bool
	{
		foreach ($this->excludeFiles as $pattern) {
			if ($filename === $pattern || fnmatch($pattern, $filename)) {
				return true;
			}
		}

		return false;
	}
}