<?php

/**

 * WP_Theme Class

 *

 * @package WordPress

 * @subpackage Theme

 * @since 3.4.0

 */

final class WP_Theme implements ArrayAccess {

	/**

	 * Whether the theme has been marked as updateable.

	 *

	 * @since 4.4.0

	 * @var bool

	 *

	 * @see WP_MS_Themes_List_Table

	 */

	public $update = false;

	/**

	 * Headers for style.css files.

	 *

	 * @var array

	 */

	private static $file_headers = array(

		'Name'        => 'Theme Name',

		'ThemeURI'    => 'Theme URI',

		'Description' => 'Description',

		'Author'      => 'Author',

		'AuthorURI'   => 'Author URI',

		'Version'     => 'Version',

		'Template'    => 'Template',

		'Status'      => 'Status',

		'Tags'        => 'Tags',

		'TextDomain'  => 'Text Domain',

		'DomainPath'  => 'Domain Path',

	);

	/**

	 * Default themes.

	 *

	 * @var array

	 */

	private static $default_themes = array(

		'classic'         => 'WordPress Classic',

		'default'         => 'WordPress Default',

		'twentyten'       => 'Twenty Ten',

		'twentyeleven'    => 'Twenty Eleven',

		'twentytwelve'    => 'Twenty Twelve',

		'twentythirteen'  => 'Twenty Thirteen',

		'twentyfourteen'  => 'Twenty Fourteen',

		'twentyfifteen'   => 'Twenty Fifteen',

		'twentysixteen'   => 'Twenty Sixteen',

		'twentyseventeen' => 'Twenty Seventeen',

		'twentynineteen'  => 'Twenty Nineteen',

	);

	/**

	 * Renamed theme tags.

	 *

	 * @var array

	 */

	private static $tag_map = array(

		'fixed-width'    => 'fixed-layout',

		'flexible-width' => 'fluid-layout',

	);

	/**

	 * Absolute path to the theme root, usually wp-content/themes

	 *

	 * @var string

	 */

	private $theme_root;

	/**

	 * Header data from the theme's style.css file.

	 *

	 * @var array

	 */

	private $headers = array();

	/**

	 * Header data from the theme's style.css file after being sanitized.

	 *

	 * @var array

	 */

	private $headers_sanitized;

	/**

	 * Header name from the theme's style.css after being translated.

	 *

	 * Cached due to sorting functions running over the translated name.

	 *

	 * @var string

	 */

	private $name_translated;

	/**

	 * Errors encountered when initializing the theme.

	 *

	 * @var WP_Error

	 */

	private $errors;

	/**

	 * The directory name of the theme's files, inside the theme root.

	 *

	 * In the case of a child theme, this is directory name of the child theme.

	 * Otherwise, 'stylesheet' is the same as 'template'.

	 *

	 * @var string

	 */

	private $stylesheet;

	/**

	 * The directory name of the theme's files, inside the theme root.

	 *

	 * In the case of a child theme, this is the directory name of the parent theme.

	 * Otherwise, 'template' is the same as 'stylesheet'.

	 *

	 * @var string

	 */

	private $template;

	/**

	 * A reference to the parent theme, in the case of a child theme.

	 *

	 * @var WP_Theme

	 */

	private $parent;

	/**

	 * URL to the theme root, usually an absolute URL to wp-content/themes

	 *

	 * @var string

	 */

	private $theme_root_uri;

	/**

	 * Flag for whether the theme's textdomain is loaded.

	 *

	 * @var bool

	 */

	private $textdomain_loaded;

	/**

	 * Stores an md5 hash of the theme root, to function as the cache key.

	 *

	 * @var string

	 */

	private $cache_hash;

	/**

	 * Flag for whether the themes cache bucket should be persistently cached.

	 *

	 * Default is false. Can be set with the {@see 'wp_cache_themes_persistently'} filter.

	 *

	 * @var bool

	 */

	private static $persistently_cache;

	/**

	 * Expiration time for the themes cache bucket.

	 *

	 * By default the bucket is not cached, so this value is useless.

	 *

	 * @var bool

	 */

	private static $cache_expiration = 1800;

	/**

	 * Constructor for WP_Theme.

	 *

	 * @since  3.4.0

	 *

	 * @global array $wp_theme_directories

	 *

	 * @param string $theme_dir Directory of the theme within the theme_root.

	 * @param string $theme_root Theme root.

	 * @param WP_Error|void $_child If this theme is a parent theme, the child may be passed for validation purposes.

	 */

	public function __construct( $theme_dir, $theme_root, $_child = null ) {

		global $wp_theme_directories;

		// Initialize caching on first run.

		if ( ! isset( self::$persistently_cache ) ) {

			/** This action is documented in wp-includes/theme.php */

			self::$persistently_cache = apply_filters( 'wp_cache_themes_persistently', false, 'WP_Theme' );

			if ( self::$persistently_cache ) {

				wp_cache_add_global_groups( 'themes' );

				if ( is_int( self::$persistently_cache ) ) {

					self::$cache_expiration = self::$persistently_cache;

				}

			} else {

				wp_cache_add_non_persistent_groups( 'themes' );

			}

		}

		$this->theme_root = $theme_root;

		$this->stylesheet = $theme_dir;

		// Correct a situation where the theme is 'some-directory/some-theme' but 'some-directory' was passed in as part of the theme root instead.

		if ( ! in_array( $theme_root, (array) $wp_theme_directories ) && in_array( dirname( $theme_root ), (array) $wp_theme_directories ) ) {

			$this->stylesheet = basename( $this->theme_root ) . '/' . $this->stylesheet;

			$this->theme_root = dirname( $theme_root );

		}

		$this->cache_hash = md5( $this->theme_root . '/' . $this->stylesheet );

		$theme_file       = $this->stylesheet . '/style.css';

		$cache = $this->cache_get( 'theme' );

		if ( is_array( $cache ) ) {

			foreach ( array( 'errors', 'headers', 'template' ) as $key ) {

				if ( isset( $cache[ $key ] ) ) {

					$this->$key = $cache[ $key ];

				}

			}

			if ( $this->errors ) {

				return;

			}

			if ( isset( $cache['theme_root_template'] ) ) {

				$theme_root_template = $cache['theme_root_template'];

			}

		} elseif ( ! file_exists( $this->theme_root . '/' . $theme_file ) ) {

			$this->headers['Name'] = $this->stylesheet;

			if ( ! file_exists( $this->theme_root . '/' . $this->stylesheet ) ) {

				$this->errors = new WP_Error( 'theme_not_found', sprintf( __( 'The theme directory "%s" does not exist.' ), esc_html( $this->stylesheet ) ) );

			} else {

				$this->errors = new WP_Error( 'theme_no_stylesheet', __( 'Stylesheet is missing.' ) );

			}

			$this->template = $this->stylesheet;

			$this->cache_add(

				'theme',

				array(

					'headers'    => $this->headers,

					'errors'     => $this->errors,

					'stylesheet' => $this->stylesheet,

					'template'   => $this->template,

				)

			);

			if ( ! file_exists( $this->theme_root ) ) { // Don't cache this one.

				$this->errors->add( 'theme_root_missing', __( 'ERROR: The themes directory is either empty or doesn’t exist. Please check your installation.' ) );

			}

			return;

		} elseif ( ! is_readable( $this->theme_root . '/' . $theme_file ) ) {

			$this->headers['Name'] = $this->stylesheet;

			$this->errors          = new WP_Error( 'theme_stylesheet_not_readable', __( 'Stylesheet is not readable.' ) );

			$this->template        = $this->stylesheet;

			$this->cache_add(

				'theme',

				array(

					'headers'    => $this->headers,

					'errors'     => $this->errors,

					'stylesheet' => $this->stylesheet,

					'template'   => $this->template,

				)

			);

			return;

		} else {

			$this->headers = get_file_data( $this->theme_root . '/' . $theme_file, self::$file_headers, 'theme' );

			// Default themes always trump their pretenders.

			// Properly identify default themes that are inside a directory within wp-content/themes.

			if ( $default_theme_slug = array_search( $this->headers['Name'], self::$default_themes ) ) {

				if ( basename( $this->stylesheet ) != $default_theme_slug ) {

					$this->headers['Name'] .= '/' . $this->stylesheet;

				}

			}

		}

		if ( ! $this->template && $this->stylesheet === $this->headers['Template'] ) {

			/* translators: %s: Template */

			$this->errors = new WP_Error( 'theme_child_invalid', sprintf( __( 'The theme defines itself as its parent theme. Please check the %s header.' ), '<code>Template</code>' ) );

			$this->cache_add(

				'theme',

				array(

					'headers'    => $this->headers,

					'errors'     => $this->errors,

					'stylesheet' => $this->stylesheet,

				)

			);

			return;

		}

		// (If template is set from cache [and there are no errors], we know it's good.)

		if ( ! $this->template && ! ( $this->template = $this->headers['Template'] ) ) {

			$this->template = $this->stylesheet;

			if ( ! file_exists( $this->theme_root . '/' . $this->stylesheet . '/index.php' ) ) {

				$error_message = sprintf(

					/* translators: 1: index.php, 2: link to documentation, 3: style.css */

					__( 'Template is missing. Standalone themes need to have a %1$s template file. <a href="%2$s">Child themes</a> need to have a Template header in the %3$s stylesheet.' ),

					'<code>index.php</code>',

					__( 'https://developer.wordpress.org/themes/advanced-topics/child-themes/' ),

					'<code>style.css</code>'

				);

				$this->errors = new WP_Error( 'theme_no_index', $error_message );

				$this->cache_add(

					'theme',

					array(

						'headers'    => $this->headers,

						'errors'     => $this->errors,

						'stylesheet' => $this->stylesheet,

						'template'   => $this->template,

					)

				);

				return;

			}

		}

		// If we got our data from cache, we can assume that 'template' is pointing to the right place.

		if ( ! is_array( $cache ) && $this->template != $this->stylesheet && ! file_exists( $this->theme_root . '/' . $this->template . '/index.php' ) ) {

			// If we're in a directory of themes inside /themes, look for the parent nearby.

			// wp-content/themes/directory-of-themes/*

			$parent_dir = dirname( $this->stylesheet );

			if ( '.' != $parent_dir && file_exists( $this->theme_root . '/' . $parent_dir . '/' . $this->template . '/index.php' ) ) {

				$this->template = $parent_dir . '/' . $this->template;

			} elseif ( ( $directories = search_theme_directories() ) && isset( $directories[ $this->template ] ) ) {

				// Look for the template in the search_theme_directories() results, in case it is in another theme root.

				// We don't look into directories of themes, just the theme root.

				$theme_root_template = $directories[ $this->template ]['theme_root'];

			} else {

				// Parent theme is missing.

				$this->errors = new WP_Error( 'theme_no_parent', sprintf( __( 'The parent theme is missing. Please install the "%s" parent theme.' ), esc_html( $this->template ) ) );

				$this->cache_add(

					'theme',

					array(

						'headers'    => $this->headers,

						'errors'     => $this->errors,

						'stylesheet' => $this->stylesheet,

						'template'   => $this->template,

					)

				);

				$this->parent = new WP_Theme( $this->template, $this->theme_root, $this );

				return;

			}

		}

		// Set the parent, if we're a child theme.

		if ( $this->template != $this->stylesheet ) {

			// If we are a parent, then there is a problem. Only two generations allowed! Cancel things out.

			if ( $_child instanceof WP_Theme && $_child->template == $this->stylesheet ) {

				$_child->parent = null;

				$_child->errors = new WP_Error( 'theme_parent_invalid', sprintf( __( 'The "%s" theme is not a valid parent theme.' ), esc_html( $_child->template ) ) );

				$_child->cache_add(

					'theme',

					array(

						'headers'    => $_child->headers,

						'errors'     => $_child->errors,

						'stylesheet' => $_child->stylesheet,

						'template'   => $_child->template,

					)

				);

				// The two themes actually reference each other with the Template header.

				if ( $_child->stylesheet == $this->template ) {

					$this->errors = new WP_Error( 'theme_parent_invalid', sprintf( __( 'The "%s" theme is not a valid parent theme.' ), esc_html( $this->template ) ) );

					$this->cache_add(

						'theme',

						array(

							'headers'    => $this->headers,

							'errors'     => $this->errors,

							'stylesheet' => $this->stylesheet,

							'template'   => $this->template,

						)

					);

				}

				return;

			}

			// Set the parent. Pass the current instance so we can do the crazy checks above and assess errors.

			$this->parent = new WP_Theme( $this->template, isset( $theme_root_template ) ? $theme_root_template : $this->theme_root, $this );

		}

		if ( wp_paused_themes()->get( $this->stylesheet ) && ( ! is_wp_error( $this->errors ) || ! isset( $this->errors->errors['theme_paused'] ) ) ) {

			$this->errors = new WP_Error( 'theme_paused', __( 'This theme failed to load properly and was paused within the admin backend.' ) );

		}

		// We're good. If we didn't retrieve from cache, set it.

		if ( ! is_array( $cache ) ) {

			$cache = array(

				'headers'    => $this->headers,

				'errors'     => $this->errors,

				'stylesheet' => $this->stylesheet,

				'template'   => $this->template,

			);

			// If the parent theme is in another root, we'll want to cache this. Avoids an entire branch of filesystem calls above.

			if ( isset( $theme_root_template ) ) {

				$cache['theme_root_template'] = $theme_root_template;

			}

			$this->cache_add( 'theme', $cache );

		}

	}

	/**

	 * When converting the object to a string, the theme name is returned.

	 *

	 * @since  3.4.0

	 *

	 * @return string Theme name, ready for display (translated)

	 */

	public function __toString() {

		return (string) $this->display( 'Name' );

	}

	/**

	 * __isset() magic method for properties formerly returned by current_theme_info()

	 *