<?php
if (!defined('ABSPATH')) {
	exit;//Exit if accessed directly
}

if (class_exists('AIOWPSecurity_Utility_File')) return;

class AIOWPSecurity_Utility_File {

	// This variable will be an array which will contain all of the files and/or directories we wish to check permissions for
	public $files_and_dirs_to_check;

	public function __construct() {
		 // Let's initiliaze our class variable array with all of the files and/or directories we wish to check permissions for.
		 // NOTE: we can add to this list in future if we wish

		//Get wp-config.php file path
		$wp_config_path = AIOWPSecurity_Utility_File::get_wp_config_file_path();
		$home_path = self::get_home_path();

		$this->files_and_dirs_to_check = array(
			array('name' => 'root directory', 'path' => ABSPATH, 'permissions' => '0755'),
			array('name' => 'wp-includes/', 'path' => ABSPATH."wp-includes", 'permissions' => '0755'),
			array('name' => '.htaccess', 'path' => $home_path.".htaccess", 'permissions' => '0644'),
			array('name' => 'wp-admin/index.php', 'path' => ABSPATH."wp-admin/index.php", 'permissions' => '0644'),
			array('name' => 'wp-admin/js/', 'path' => ABSPATH."wp-admin/js/", 'permissions' => '0755'),
			array('name' => 'wp-content/themes/', 'path' => WP_CONTENT_DIR."/themes", 'permissions' => '0755'),
			array('name' => 'wp-content/plugins/', 'path' => WP_PLUGIN_DIR, 'permissions' => '0755'),
			array('name' => 'wp-admin/', 'path' => ABSPATH."wp-admin", 'permissions' => '0755'),
			array('name' => 'wp-content/', 'path' => WP_CONTENT_DIR, 'permissions' => '0755'),
			array('name' => 'wp-config.php', 'path' => $wp_config_path, 'permissions' => '0640'),
			//Add as many files or dirs as needed by following the convention above
		);

	}

	/**
	 * Returns full path to mu-plugin directory
	 *
	 * @return string
	 */
	public static function get_mu_plugin_dir() {
		return WPMU_PLUGIN_DIR;
	}

	/**
	 * Returns path to wp-config
	 *
	 * @return string
	 */
	public static function get_wp_config_file_path() {
		$wp_config_file = ABSPATH . 'wp-config.php';
		if (file_exists($wp_config_file)) {
			return $wp_config_file;
		} elseif (file_exists(dirname(ABSPATH) . '/wp-config.php')) {
			return dirname(ABSPATH) . '/wp-config.php';
		}
		return $wp_config_file;
	}

	public static function write_content_to_file($file_path, $new_contents) {
		// Get the file permissions so we can revert back to it when we are done
		$permissions = octdec(substr(sprintf('%o', fileperms($file_path)), -4));
		@chmod($file_path, 0777);
		if (is_writeable($file_path)) {
			$handle = fopen($file_path, 'w');
			foreach ($new_contents as $line) {
				fwrite($handle, $line);
			}
			fclose($handle);
			@chmod($file_path, $permissions); //Let's change the file back to it's original permission setting
			return true;
		} else {
				return false;
		}
	}

	public static function backup_a_file($src_file_path, $suffix = 'backup') {
		$backup_file_path = $src_file_path . '.' . $suffix;
		if (!copy($src_file_path, $backup_file_path)) {
			//Failed to make a backup copy
			return false;
		}
		return true;
	}

	public static function backup_and_rename_wp_config($src_file_path, $prefix = 'backup') {
		global $aio_wp_security;

		//Check to see if the main "backups" directory exists - create it otherwise
		$aiowps_backup_dir = WP_CONTENT_DIR.'/'.AIO_WP_SECURITY_BACKUPS_DIR_NAME;
		if (!AIOWPSecurity_Utility_File::create_dir($aiowps_backup_dir)) {
			$aio_wp_security->debug_logger->log_debug("backup_and_rename_wp_config - Creation of backup directory failed!", 4);
			return false;
		}

		$src_parts = pathinfo($src_file_path);
		$backup_file_name = $prefix . '.' . $src_parts['basename'];

		$backup_file_path = $aiowps_backup_dir . '/' . $backup_file_name;
		if (!copy($src_file_path, $backup_file_path)) {
			//Failed to make a backup copy
			return false;
		}
		return true;
	}

	public static function backup_and_rename_htaccess($src_file_path, $suffix = 'backup') {
		global $aio_wp_security;

		//Check to see if the main "backups" directory exists - create it otherwise
		$aiowps_backup_dir = WP_CONTENT_DIR.'/'.AIO_WP_SECURITY_BACKUPS_DIR_NAME;
		if (!AIOWPSecurity_Utility_File::create_dir($aiowps_backup_dir)) {
			$aio_wp_security->debug_logger->log_debug("backup_and_rename_htaccess - Creation of backup directory failed!", 4);
			return false;
		}

		$src_parts = pathinfo($src_file_path);
		$backup_file_name = $src_parts['basename'] . '.' . $suffix;

		$backup_file_path = $aiowps_backup_dir . '/' . $backup_file_name;
		if (!copy($src_file_path, $backup_file_path)) {
			//Failed to make a backup copy
			return false;
		}
		return true;
	}

	/**
	 * Function which reads entire contents of a file and stores serialized contents into our global_meta table
	 *
	 * @param string $src_file_path
	 * @param string $key_description
	 * @return void
	 */
	public static function backup_file_contents_to_db($src_file_path, $key_description) {
		global $wpdb, $aio_wp_security;
		$file_contents = AIOWPSecurity_Utility_File::get_file_contents($src_file_path);

		$payload = serialize($file_contents);
		$date_time = current_time('mysql');
		$data = array('date_time' => $date_time, 'meta_key1' => $key_description, 'meta_value2' => $payload);

		//First check if a backup entry already exists in the global_meta table
		$aiowps_global_meta_tbl_name = AIOWPSEC_TBL_GLOBAL_META_DATA;
		$resultset = $wpdb->get_row($wpdb->prepare("SELECT * FROM $aiowps_global_meta_tbl_name WHERE meta_key1 = %s", $key_description));
		if ($resultset) {
			$where = array('meta_key1' => $key_description);
			$res = $wpdb->update($aiowps_global_meta_tbl_name, $data, $where);
		} else {
			$res = $wpdb->insert($aiowps_global_meta_tbl_name, $data);
		}

		if (false === $res) {
			$aio_wp_security->debug_logger->log_debug("AIOWPSecurity_Utility_File::backup_file_contents_to_db() - Unable to write entry to DB", 4);
		}
	}


	/**
	 * This function will perform a recursive search for files in the path that match the passed in pattern
	 *
	 * @param string  $pattern - the file pattern to search for
	 * @param integer $flags   - flags to apply on the search
	 * @param string  $path    - the path we want to search
	 *
	 * @return boolean|array - an array of files matching the pattern or false if there was an error (directory traversal in path) or none found
	 */
	public static function recursive_file_search($pattern = '*', $flags = 0, $path = '') {
		$paths = glob($path.'*', GLOB_MARK|GLOB_ONLYDIR|GLOB_NOSORT);
		if (false === $paths) {
			return false;
		}
		$files = glob($path.$pattern, $flags);
		if (false === $files) {
			return false;
		}
		foreach ($paths as $path) {
			$files = array_merge($files, AIOWPSecurity_Utility_File::recursive_file_search($pattern, $flags, $path));
		}
		return $files;
	}

	/**
	 * Useful when wanting to echo file contents to screen with <br /> tags
	 *
	 * @param string $src_file
	 * @return string
	 */
	public static function get_file_contents_with_br($src_file) {
		$file_contents = file_get_contents($src_file);
		return nl2br($file_contents);
	}

	/**
	 * Useful when wanting to echo file contents inside textarea
	 *
	 * @param string $src_file
	 * @return string
	 */
	public static function get_file_contents($src_file) {
		$file_contents = file_get_contents($src_file);
		return $file_contents;
	}

	/**
	 * Returns the file's permission value eg, "0755"
	 *
	 * @param string $filepath
	 * @return string
	 */
	public static function get_file_permission($filepath) {
		if (!function_exists('fileperms')) {
			$perms = '-1';
		} else {
			clearstatcache();
			$perms = substr(sprintf("%o", @fileperms($filepath)), -4);
		}
		return $perms;
	}

	/**
	 * Checks if a write operation is possible for the file in question
	 *
	 * @param string $filepath
	 * @return boolean
	 */
	public static function is_file_writable($filepath) {
		$test_string = ""; //We will attempt to append an empty string at the end of the file for the test
		$write_result = @file_put_contents($filepath, $test_string, FILE_APPEND | LOCK_EX);
		if (false === $write_result) {
			return false;
		} else {
			return true;
		}
	}

	public static function download_a_file_option1($file_path, $file_name = '') {
		$file = $file_path;//Full ABS path to the file
		if (empty($file_name)) {
			$file_name = basename($file);
		}

		header('Content-Description: File Transfer');
		header('Content-Type: application/octet-stream');
		header('Content-Disposition: attachment; filename='.$file_name);
		header('Content-Transfer-Encoding: binary');
		header('Expires: 0');
		header('Cache-Control: must-revalidate');
		header('Pragma: public');
		header('Content-Length: ' . filesize($file));
		//ob_clean();
		//flush();
		readfile($file);
		exit;
	}

	public static function download_content_to_a_file($output, $file_name = '') {
		if (empty($file_name)) {
			$file_name = "aiowps_" . date("Y-m-d_H-i", time()).".txt";
		}

		header("Content-Encoding: UTF-8");
		header("Cache-Control: must-revalidate, post-check=0, pre-check=0");
		header("Content-Description: File Transfer");
		header("Content-type: application/octet-stream");
		header("Content-disposition: attachment; filename=" . $file_name);
		header("Content-Transfer-Encoding: binary");
		header("Content-Length: " . strlen($output));
		echo $output;
		exit;
	}

	/**
	 * This function will compare the current permission value for a file or dir with the recommended value.
	 * It will compare the individual "execute", "write" and "read" bits for the "public", "group" and "owner" permissions.
	 * If the permissions for an actual bit value are greater than the recommended value it returns '0' (=less secure)
	 * Otherwise it returns '1' which means it is secure
	 * Accepts permission value parameters in octal, ie, "0777" or "777"
	 *
	 * @param string $recommended
	 * @param string $actual
	 * @return boolean
	 */
	public static function is_file_permission_secure($recommended, $actual) {
		$result = 1; //initialize return result

		//Check "public" permissions
		$public_value_actual = substr($actual, -1, 1); //get dec value for actual public permission
		$public_value_rec = substr($recommended, -1, 1); //get dec value for recommended public permission

		$pva_bin = sprintf('%04b', $public_value_actual); //Convert value to binary
		$pvr_bin = sprintf('%04b', $public_value_rec); //Convert value to binary
		//Compare the "executable" bit values for the public actual versus the recommended
		if (substr($pva_bin, -1, 1)<=substr($pvr_bin, -1, 1)) {
			//The "execute" bit is the same or less as the recommended value
			$result = 1*$result;
		} else {
			//The "execute" bit is switched on for the actual value - meaning it is less secure
			$result = 0*$result;
		}

		//Compare the "write" bit values for the public actual versus the recommended
		if (substr($pva_bin, -2, 1)<=substr($pvr_bin, -2, 1)) {
			//The "write" bit is the same or less as the recommended value
			$result = 1*$result;
		} else {
			//The "write" bit is switched on for the actual value - meaning it is less secure
			$result = 0*$result;
		}

		//Compare the "read" bit values for the public actual versus the recommended
		if (substr($pva_bin, -3, 1)<=substr($pvr_bin, -3, 1)) {
			//The "read" bit is the same or less as the recommended value
			$result = 1*$result;
		} else {
			//The "read" bit is switched on for the actual value - meaning it is less secure
			$result = 0*$result;
		}

		//Check "group" permissions
		$group_value_actual = substr($actual, -2, 1);
		$group_value_rec = substr($recommended, -2, 1);
		$gva_bin = sprintf('%04b', $group_value_actual); //Convert value to binary
		$gvr_bin = sprintf('%04b', $group_value_rec); //Convert value to binary

		//Compare the "executable" bit values for the group actual versus the recommended
		if (substr($gva_bin, -1, 1)<=substr($gvr_bin, -1, 1)) {
			//The "execute" bit is the same or less as the recommended value
			$result = 1*$result;
		} else {
			//The "execute" bit is switched on for the actual value - meaning it is less secure
			$result = 0*$result;
		}

		//Compare the "write" bit values for the public actual versus the recommended
		if (substr($gva_bin, -2, 1)<=substr($gvr_bin, -2, 1)) {
			//The "write" bit is the same or less as the recommended value
			$result = 1*$result;
		} else {
			//The "write" bit is switched on for the actual value - meaning it is less secure
			$result = 0*$result;
		}

		//Compare the "read" bit values for the public actual versus the recommended
		if (substr($gva_bin, -3, 1)<=substr($gvr_bin, -3, 1)) {
			//The "read" bit is the same or less as the recommended value
			$result = 1*$result;
		} else {
			//The "read" bit is switched on for the actual value - meaning it is less secure
			$result = 0*$result;
		}

		//Check "owner" permissions
		$owner_value_actual = substr($actual, -3, 1);
		$owner_value_rec = substr($recommended, -3, 1);
		$ova_bin = sprintf('%04b', $owner_value_actual); //Convert value to binary
		$ovr_bin = sprintf('%04b', $owner_value_rec); //Convert value to binary

		//Compare the "executable" bit values for the group actual versus the recommended
		if (substr($ova_bin, -1, 1)<=substr($ovr_bin, -1, 1)) {
			//The "execute" bit is the same or less as the recommended value
			$result = 1*$result;
		} else {
			//The "execute" bit is switched on for the actual value - meaning it is less secure
			$result = 0*$result;
		}

		//Compare the "write" bit values for the public actual versus the recommended
		if (substr($ova_bin, -2, 1)<=substr($ovr_bin, -2, 1)) {
			//The "write" bit is the same or less as the recommended value
			$result = 1*$result;
		} else {
			//The "write" bit is switched on for the actual value - meaning it is less secure
			$result = 0*$result;
		}

		//Compare the "read" bit values for the public actual versus the recommended
		if (substr($ova_bin, -3, 1)<=substr($ovr_bin, -3, 1)) {
			//The "read" bit is the same or less as the recommended value
			$result = 1*$result;
		} else {
			//The "read" bit is switched on for the actual value - meaning it is less secure
			$result = 0*$result;
		}

		return $result;
	}

	/**
	 * Checks if a directory exists and creates one if it does not
	 *
	 * @param string $dirpath
	 * @return boolean
	 */
	public static function create_dir($dirpath = '') {
		$res = true;
		if ('' != $dirpath) {
			//TODO - maybe add some checks to make sure someone is not passing a path with a filename, ie, something which has ".<extenstion>" at the end
			//$path_parts = pathinfo($dirpath);
			//$dirpath = $path_parts['dirname'] . '/' . $path_parts['basename'];
			if (!file_exists($dirpath)) {
				$res = mkdir($dirpath, 0755);
			}
		}
		return $res;
	}

	public static function get_attachment_id_from_url($attachment_url = '') {
		global $wpdb;
		$attachment_id = false;

		// If there is no url, return.
		if ('' == $attachment_url)return;

		// Get the upload directory paths
		$upload_dir_paths = wp_upload_dir();

		// Make sure the upload path base directory exists in the attachment URL, to verify that we're working with a media library image
		if (false !== strpos($attachment_url, $upload_dir_paths['baseurl'])) {
			// Remove the upload path base directory from the attachment URL
			$attachment_url = str_replace($upload_dir_paths['baseurl'] . '/', '', $attachment_url);
			// Now run custom database query to get attachment ID from attachment URL
			$attachment_id = $wpdb->get_var($wpdb->prepare("SELECT wposts.ID FROM $wpdb->posts wposts, $wpdb->postmeta wpostmeta WHERE wposts.ID = wpostmeta.post_id AND wpostmeta.meta_key = '_wp_attached_file' AND wpostmeta.meta_value = %s AND wposts.post_type = 'attachment'", $attachment_url));
		}
		return $attachment_id;
	}


	/**
	 * Will return an indexed array of files sorted by last modified timestamp
	 *
	 * @param string $dir
	 * @param string $sort (ASC, DESC)
	 * @return array
	 */
	public static function scan_dir_sort_date($dir, $sort = 'DESC') {
		$files = array();
		foreach (scandir($dir) as $file) {
			$files[$file] = filemtime($dir . '/' . $file);
		}

		if ('ASC' === $sort) {
			asort($files);
		} else {
			arsort($files);
		}

		return array_keys($files);
	}

	/**
	 * Remove a directory from the local filesystem
	 *
	 * @param string  $dir			 - the directory
	 * @param boolean $contents_only - if set to true, then do not remove the directory, but only empty it of contents
	 *
	 * @return boolean - success/failure
	 */
	public static function remove_local_directory($dir, $contents_only = false) {
		
		$handle = opendir($dir);
		if ($handle) {
			while (false !== ($entry = readdir($handle))) {
				if ('.' !== $entry && '..' !== $entry) {
					if (is_dir($dir.'/'.$entry)) {
						self::remove_local_directory($dir.'/'.$entry, false);
					} else {
						@unlink($dir.'/'.$entry);// phpcs:ignore Generic.PHP.NoSilencedErrors.Discouraged -- ignore warning and proceed to try and remove the rest of the files
					}
				}
			}
			if (is_resource($handle)) closedir($handle);
		}

		return $contents_only ? true : rmdir($dir);
	}

	/**
	 * Get home path.
	 *
	 * @return string
	 */
	public static function get_home_path() {
		// Make the scope of $wp_file_descriptions global, so that when wp-admin/includes/file.php assigns to it, it is adjusting the global variable as intended
		global $wp_file_descriptions; // phpcs:ignore VariableAnalysis.CodeAnalysis.VariableAnalysis.UnusedVariable -- We need to make this global see above comment
		if (!function_exists('get_home_path')) require_once(ABSPATH. '/wp-admin/includes/file.php');
		return wp_normalize_path(get_home_path());
	}
}