<?php
/**
 * Class description
 *
 * @package   package_name
 * @author    Cherry Team
 * @license   GPL-2.0+
 */

// If this file is called directly, abort.
if ( ! defined( 'WPINC' ) ) {
	die;
}

if ( ! class_exists( 'Jet_Theme_Core_Backups' ) ) {

	/**
	 * Define Jet_Theme_Core_Backups class
	 */
	class Jet_Theme_Core_Backups {

		/**
		 * Path to backup file
		 * @var string
		 */
		public $path;

		/**
		 * Theme files to backup
		 * @var array
		 */
		public $files = array();

		/**
		 * Messages holder
		 * @var string
		 */
		public $message = null;

		/**
		 * A reference to an instance of this class.
		 *
		 * @since 1.0.0
		 * @var   object
		 */
		private static $instance = null;

		/**
		 * Constructor for the class
		 */
		public function __construct() {

			// connect filesystem
			$this->fs_connect();

			// set path
			$upload_dir      = wp_upload_dir();
			$upload_base_dir = $upload_dir['basedir'];
			$this->path      = trailingslashit( $upload_base_dir ) . 'kava-backups';

		}

		/**
		 * Try to create backup archive
		 *
		 * @since  1.0.0
		 * @return bool
		 */
		public function make_backup( $theme, $version ) {

			global $wp_filesystem;

			if ( ! current_user_can( 'manage_options' ) ) {
				return false;
			}

			include_once( ABSPATH . '/wp-admin/includes/class-pclzip.php' );

			if ( ! $this->check_path() ) {
				return false;
			}

			$this->protect_path();

			ini_set( 'max_execution_time', -1 );
			set_time_limit( 0 );

			$zip_name    = $this->path . '/' . $theme . '-' . $version . '.zip';
			$files       = $this->get_files( $theme );
			$files       = implode( ',', $files );
			$remove_path = $wp_filesystem->wp_themes_dir();
			$zip         = new PclZip( $zip_name );
			$result      = $zip->create( $files, PCLZIP_OPT_REMOVE_PATH, $remove_path );

			if ( ! $result ) {
				return false;
			}

			return str_replace( ABSPATH, home_url( '/' ), $zip_name );

		}

		/**
		 * Get backup files list
		 *
		 * @since  1.0.0
		 * @return array
		 */
		public function get_files( $theme ) {
			global $wp_filesystem;
			$path = $wp_filesystem->wp_themes_dir() . $theme;
			$this->parse_dir( $path );
			return $this->files;
		}

		/**
		 * Recursive function, that parse passed directory and add found files into 'file' property.
		 *
		 * @since  1.0.0
		 * @param  string $dir path to directory to search files in.
		 * @return void|bool false
		 */
		public function parse_dir( $dir ) {

			global $wp_filesystem;

			$files = $wp_filesystem->dirlist( $dir );

			if ( ! is_array( $files ) ) {
				return false;
			}

			foreach ( $wp_filesystem->dirlist( $dir ) as $name => $data ) {
				$current_path = trailingslashit( $dir ) . $name;
				if ( 'd' == $data['type'] ) {
					$this->parse_dir( $current_path );
					continue;
				}

				$this->files[] = $current_path;
			}

		}

		/**
		 * Check if backup directory exists and create it if not
		 *
		 * @since  1.0.0
		 * @return bool
		 */
		public function check_path() {

			global $wp_filesystem;
			$path = $this->prepare_path( $this->path );

			if ( $wp_filesystem->exists( $path ) ) {
				return true;
			}

			return $wp_filesystem->mkdir( $path );

		}

		/**
		 * Create .htaccess file in updates backup dir to protect it from direct access
		 *
		 * @since  1.0.0
		 * @return void|bool
		 */
		public function protect_path() {

			global $wp_filesystem;
			$path = $this->prepare_path( $this->path );

			$file = $path . '/.htaccess';

			if ( $wp_filesystem->exists( $file ) ) {
				return true;
			}

			$wp_filesystem->put_contents( $file, 'deny from all' );

		}

		/**
		 * Prepeare path for using with filesystem API
		 *
		 * @since  1.0.0
		 * @param  string $path path to prepare.
		 * @return string
		 */
		public function prepare_path( $path ) {
			global $wp_filesystem;
			return str_replace( ABSPATH, $wp_filesystem->abspath(), $path );
		}

		/**
		 * Get avaliable backups list
		 *
		 * @since  1.0.0
		 * @return array
		 */
		public function get_backups() {

			global $wp_filesystem;

			$path   = $this->prepare_path( $this->path );
			$files  = $wp_filesystem->dirlist( $path );
			$result = array();

			if ( ! is_array( $files ) ) {
				return $result;
			}

			if ( isset( $files['.htaccess'] ) ) {
				unset( $files['.htaccess'] );
			}

			foreach ( $files as $file => $data ) {
				if ( 'zip' !== pathinfo( $file, PATHINFO_EXTENSION ) ) {
					continue;
				}

				$result[] = array(
					'name' => $file,
					'date' => date( 'M d Y, H:i', $data['lastmodunix'] ),
				);
			}

			usort( $result, array( $this, 'date_compare' ) );

			return $result;

		}

		/**
		 * Compare backups by date
		 *
		 * @since  1.0.0
		 * @param  array $a 1st value.
		 * @param  array $b 2nd value.
		 * @return bool
		 */
		public function date_compare( $a, $b ) {
			$t1 = strtotime( $a['date'] );
			$t2 = strtotime( $b['date'] );
			return $t2 - $t1;
		}

		/**
		 * Download backup by filename
		 *
		 * @since  1.0.0
		 * @param  string $file backup filename.
		 * @return void|bool false
		 */
		public function download_backup( $file ) {

			if ( ! current_user_can( 'manage_options' ) ) {
				$this->message = __( 'Permission denied', 'jet-theme-core' );
				return false;
			}

			global $wp_filesystem;

			$path     = $this->prepare_path( $this->path );
			$filepath = $path . '/' . $file;

			if ( ! $wp_filesystem->exists( $filepath ) ) {
				$this->message = __( 'File not exists', 'jet-theme-core' );
				return false;
			}

			session_write_close();

			header( 'Pragma: public' );
			header( 'Expires: 0' );
			header( 'Cache-Control: must-revalidate, post-check=0, pre-check=0' );
			header( 'Cache-Control: public' );
			header( 'Content-Description: File Transfer' );
			header( 'Content-type: application/octet-stream' );
			header( 'Content-Disposition: attachment; filename="' . $file . '"' );
			header( 'Content-Transfer-Encoding: binary' );
			header( 'Content-Length: ' . @filesize( $filepath ) );

			$this->readfile_chunked( $filepath ) or header( 'Location: ' . $filepath );

			exit();

		}

		/**
		 * Delete existing backup by filename
		 *
		 * @since  1.0.0
		 * @param  string $file backup filename.
		 * @return bool
		 */
		public function delete_backup( $file ) {

			if ( ! current_user_can( 'manage_options' ) ) {
				$this->message = __( 'Permission denied', 'jet-theme-core' );
				return false;
			}

			global $wp_filesystem;

			$path     = $this->prepare_path( $this->path );
			$filepath = $path . '/' . $file;

			if ( ! $wp_filesystem->exists( $filepath ) ) {
				$this->message = __( 'File not exists', 'jet-theme-core' );
				return false;
			}

			$delete = $wp_filesystem->delete( $filepath );

			if ( false === $delete ) {
				$this->message = __( 'Can\'t delete selected backup', 'jet-theme-core' );
			}

			return $delete;

		}

		/**
		 * Chunked file reading
		 *
		 * @since  1.0.0
		 * @param  string  $file     fileptah.
		 * @param  boolean $retbytes return bytes number or not.
		 * @return bool|int
		 */
		public function readfile_chunked( $file, $retbytes = true ) {

			$chunksize = 1024 * 1024;
			$buffer    = '';
			$cnt       = 0;
			$handle    = @fopen( $file, 'r' );

			if ( $size = @filesize( $file ) ) {
				header( 'Content-Length: ' . $size );
			}

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

			while ( ! @feof( $handle ) ) {
				$buffer = @fread( $handle, $chunksize );
				echo $buffer;
				ob_flush();
				flush();
				if ( $retbytes ) {
					$cnt += strlen( $buffer );
				}
			}

			$status = @fclose( $handle );

			if ( $retbytes && $status ) {
				return $cnt;
			}

			return $status;
		}

		/**
		 * Check if backup manager returned any messages during processing
		 *
		 * @since  1.0.0
		 * @return string
		 */
		public function get_message() {
			return (string) $this->message;
		}

		/**
		 * Connect to the filesystem.
		 *
		 * @since 1.0.0
		 *
		 * @param array $directories                  Optional. A list of directories. If any of these do
		 *                                            not exist, a {@see WP_Error} object will be returned.
		 *                                            Default empty array.
		 * @param bool  $allow_relaxed_file_ownership Whether to allow relaxed file ownership.
		 *                                            Default false.
		 * @return bool|WP_Error True if able to connect, false or a {@see WP_Error} otherwise.
		 */
		public function fs_connect( $directories = array(), $allow_relaxed_file_ownership = false ) {

			global $wp_filesystem;

			if ( ! function_exists( 'request_filesystem_credentials' ) ) {
				include_once ( ABSPATH . '/wp-admin/includes/file.php' );
			}

			$url = admin_url( 'options.php' );

			if ( false === ( $credentials = request_filesystem_credentials( $url, '', false, false, array(), $allow_relaxed_file_ownership ) ) ) {
				return false;
			}

			if ( ! empty( $directories[0] ) ) {
				$dirs = $directories[0];
			} else {
				$dirs = array();
			}

			if ( ! WP_Filesystem( $credentials, $dirs, $allow_relaxed_file_ownership ) ) {
				$error = true;
				if ( is_object( $wp_filesystem ) && $wp_filesystem->errors->get_error_code() ) {
					$error = $wp_filesystem->errors;
				}
				return false;
			}

			if ( ! is_object( $wp_filesystem ) ) {
				return new WP_Error( 'fs_unavailable', $this->strings['fs_unavailable'] );
			}

			if ( is_wp_error( $wp_filesystem->errors ) && $wp_filesystem->errors->get_error_code() ) {
				return new WP_Error( 'fs_error', $this->strings['fs_error'], $wp_filesystem->errors );
			}

			foreach ( (array) $directories as $dir ) {
				switch ( $dir ) {
					case ABSPATH:
						if ( ! $wp_filesystem->abspath() ) {
							return new WP_Error( 'fs_no_root_dir', $this->strings['fs_no_root_dir'] );
						}
						break;
					case WP_CONTENT_DIR:
						if ( ! $wp_filesystem->wp_content_dir() ) {
							return new WP_Error( 'fs_no_content_dir', $this->strings['fs_no_content_dir'] );
						}
						break;
					case WP_PLUGIN_DIR:
						if ( ! $wp_filesystem->wp_plugins_dir() ) {
							return new WP_Error( 'fs_no_plugins_dir', $this->strings['fs_no_plugins_dir'] );
						}
						break;
					case get_theme_root():
						if ( ! $wp_filesystem->wp_themes_dir() ) {
							return new WP_Error( 'fs_no_themes_dir', $this->strings['fs_no_themes_dir'] );
						}
						break;
					default:
						if ( ! $wp_filesystem->find_folder( $dir ) ) {
							return new WP_Error( 'fs_no_folder', sprintf( $this->strings['fs_no_folder'], esc_html( basename( $dir ) ) ) );
						}
						break;
				}
			}

			return true;
		}

	}

}