<?php
/**
 * @package Polylang
 */

/**
 * A class for the Polylang settings pages, accessible from @see PLL().
 *
 * @since 1.2
 */
class PLL_Settings extends PLL_Admin_Base {

	/**
	 * @var PLL_Admin_Model
	 */
	public $model;

	/**
	 * Name of the active module.
	 *
	 * @var string|null
	 */
	protected $active_tab;

	/**
	 * Array of modules classes.
	 *
	 * @var PLL_Settings_Module[]|null
	 */
	protected $modules;

	/**
	 * Constructor
	 *
	 * @since 1.2
	 *
	 * @param PLL_Links_Model $links_model Reference to the links model.
	 */
	public function __construct( &$links_model ) {
		parent::__construct( $links_model );

		if ( isset( $_GET['page'] ) ) { // phpcs:ignore WordPress.Security.NonceVerification
			$this->active_tab = 'mlang' === $_GET['page'] ? 'lang' : substr( sanitize_key( $_GET['page'] ), 6 ); // phpcs:ignore WordPress.Security.NonceVerification
		}

		PLL_Admin_Strings::init();

		add_action( 'admin_init', array( $this, 'register_settings_modules' ) );

		// Adds screen options and the about box in the languages admin panel
		add_action( 'load-toplevel_page_mlang', array( $this, 'load_page' ) );
		add_action( 'load-languages_page_mlang_strings', array( $this, 'load_page_strings' ) );

		// Saves per-page value in screen option
		add_filter( 'set-screen-option', array( $this, 'set_screen_option' ), 10, 3 );
	}

	/**
	 * Initializes the modules
	 *
	 * @since 1.8
	 *
	 * @return void
	 */
	public function register_settings_modules() {
		$modules = array();

		if ( $this->model->get_languages_list() ) {
			$modules = array(
				'PLL_Settings_Url',
				'PLL_Settings_Browser',
				'PLL_Settings_Media',
				'PLL_Settings_CPT',
			);
		}

		$modules[] = 'PLL_Settings_Licenses';

		/**
		 * Filter the list of setting modules
		 *
		 * @since 1.8
		 *
		 * @param array $modules the list of module classes
		 */
		$modules = apply_filters( 'pll_settings_modules', $modules );

		foreach ( $modules as $key => $class ) {
			$key = is_numeric( $key ) ? strtolower( str_replace( 'PLL_Settings_', '', $class ) ) : $key;
			$this->modules[ $key ] = new $class( $this );
		}
	}

	/**
	 * Loads the about metabox
	 *
	 * @since 0.8
	 *
	 * @return void
	 */
	public function metabox_about() {
		include __DIR__ . '/view-about.php';
	}

	/**
	 * Adds screen options and the about box in the languages admin panel
	 *
	 * @since 0.9.5
	 *
	 * @return void
	 */
	public function load_page() {
		if ( ! defined( 'PLL_DISPLAY_ABOUT' ) || PLL_DISPLAY_ABOUT ) {
			add_meta_box(
				'pll-about-box',
				__( 'About Polylang', 'polylang' ),
				array( $this, 'metabox_about' ),
				'toplevel_page_mlang',
				'normal'
			);
		}

		add_screen_option(
			'per_page',
			array(
				'label'   => __( 'Languages', 'polylang' ),
				'default' => 10,
				'option'  => 'pll_lang_per_page',
			)
		);

		add_action( 'admin_notices', array( $this, 'notice_objects_with_no_lang' ) );
	}

	/**
	 * Adds screen options in the strings translations admin panel
	 *
	 * @since 2.1
	 *
	 * @return void
	 */
	public function load_page_strings() {
		add_screen_option(
			'per_page',
			array(
				'label'   => __( 'Strings translations', 'polylang' ),
				'default' => 10,
				'option'  => 'pll_strings_per_page',
			)
		);
	}

	/**
	 * Save the "Views/Uploads per page" option set by this user
	 *
	 * @since 0.9.5
	 *
	 * @param mixed  $status false or value returned by previous filter
	 * @param string $option Name of the option being changed
	 * @param string $value  Value of the option
	 *
	 * @return string New value if this is our option, otherwise nothing
	 */
	public function set_screen_option( $status, $option, $value ) {
		return 'pll_lang_per_page' === $option || 'pll_strings_per_page' === $option ? $value : $status;
	}

	/**
	 * Manages the user input for the languages pages
	 *
	 * @since 1.9
	 *
	 * @param string $action
	 * @return void
	 */
	public function handle_actions( $action ) {
		switch ( $action ) {
			case 'add':
				check_admin_referer( 'add-lang', '_wpnonce_add-lang' );
				$errors = $this->model->add_language( $_POST );

				if ( is_wp_error( $errors ) ) {
					foreach ( $errors->get_error_messages() as $message ) {
						add_settings_error( 'general', 'pll_add_language', $message );
					}
				} else {
					add_settings_error( 'general', 'pll_languages_created', __( 'Language added.', 'polylang' ), 'updated' );
					$locale = sanitize_text_field( wp_unslash( $_POST['locale'] ) ); // phpcs:ignore WordPress.Security

					if ( 'en_US' !== $locale && current_user_can( 'install_languages' ) ) {
						// Attempts to install the language pack
						require_once ABSPATH . 'wp-admin/includes/translation-install.php';
						if ( ! wp_download_language_pack( $locale ) ) {
							add_settings_error( 'general', 'pll_download_mo', __( 'The language was created, but the WordPress language file was not downloaded. Please install it manually.', 'polylang' ) );
						}

						// Force checking for themes and plugins translations updates
						wp_clean_themes_cache();
						wp_clean_plugins_cache();
					}
				}
				self::redirect(); // To refresh the page ( possible thanks to the $_GET['noheader']=true )
				break;

			case 'delete':
				check_admin_referer( 'delete-lang' );

				if ( ! empty( $_GET['lang'] ) && $this->model->delete_language( (int) $_GET['lang'] ) ) {
					add_settings_error( 'general', 'pll_languages_deleted', __( 'Language deleted.', 'polylang' ), 'updated' );
				}

				self::redirect(); // To refresh the page ( possible thanks to the $_GET['noheader']=true )
				break;

			case 'update':
				check_admin_referer( 'add-lang', '_wpnonce_add-lang' );
				$errors = $this->model->update_language( $_POST );

				if ( is_wp_error( $errors ) ) {
					foreach ( $errors->get_error_messages() as $message ) {
						add_settings_error( 'general', 'pll_update_language', $message );
					}
				} else {
					add_settings_error( 'general', 'pll_languages_updated', __( 'Language updated.', 'polylang' ), 'updated' );
				}

				self::redirect(); // To refresh the page ( possible thanks to the $_GET['noheader']=true )
				break;

			case 'default-lang':
				check_admin_referer( 'default-lang' );

				if ( $lang = $this->model->get_language( (int) $_GET['lang'] ) ) {
					$this->model->update_default_lang( $lang->slug );
				}

				self::redirect(); // To refresh the page ( possible thanks to the $_GET['noheader']=true )
				break;

			case 'content-default-lang':
				check_admin_referer( 'content-default-lang' );

				if ( $nolang = $this->model->get_objects_with_no_lang() ) {
					if ( ! empty( $nolang['posts'] ) ) {
						$this->model->set_language_in_mass( 'post', $nolang['posts'], $this->options['default_lang'] );
					}
					if ( ! empty( $nolang['terms'] ) ) {
						$this->model->set_language_in_mass( 'term', $nolang['terms'], $this->options['default_lang'] );
					}
				}

				self::redirect(); // To refresh the page ( possible thanks to the $_GET['noheader']=true )
				break;

			case 'activate':
				check_admin_referer( 'pll_activate' );
				if ( isset( $_GET['module'] ) ) {
					$module = sanitize_key( $_GET['module'] );
					if ( isset( $this->modules[ $module ] ) ) {
						$this->modules[ $module ]->activate();
					}
				}
				self::redirect();
				break;

			case 'deactivate':
				check_admin_referer( 'pll_deactivate' );
				if ( isset( $_GET['module'] ) ) {
					$module = sanitize_key( $_GET['module'] );
					if ( isset( $this->modules[ $module ] ) ) {
						$this->modules[ $module ]->deactivate();
					}
				}
				self::redirect();
				break;

			default:
				/**
				 * Fires when a non default action has been sent to Polylang settings
				 *
				 * @since 1.8
				 */
				do_action( "mlang_action_$action" );
				break;
		}
	}

	/**
	 * Displays the 3 tabs pages: languages, strings translations, settings
	 * Also manages user input for these pages
	 *
	 * @since 0.1
	 *
	 * @return void
	 */
	public function languages_page() {
		switch ( $this->active_tab ) {
			case 'lang':
				// Prepare the list table of languages
				$list_table = new PLL_Table_Languages();
				$list_table->prepare_items( $this->model->get_languages_list() );
				break;

			case 'strings':
				$string_table = new PLL_Table_String( $this->model->get_languages_list() );
				$string_table->prepare_items();
				break;
		}

		// Handle user input
		$action = isset( $_REQUEST['pll_action'] ) ? sanitize_key( $_REQUEST['pll_action'] ) : ''; // phpcs:ignore WordPress.Security.NonceVerification
		if ( 'edit' === $action && ! empty( $_GET['lang'] ) ) { // phpcs:ignore WordPress.Security.NonceVerification
			// phpcs:ignore WordPress.Security.NonceVerification, VariableAnalysis.CodeAnalysis.VariableAnalysis.UnusedVariable
			$edit_lang = $this->model->get_language( (int) $_GET['lang'] );
		} else {
			$this->handle_actions( $action );
		}

		// Displays the page
		include __DIR__ . '/view-languages.php';
	}

	/**
	 * Enqueues scripts and styles
	 *
	 * @return void
	 */
	public function admin_enqueue_scripts() {
		parent::admin_enqueue_scripts();

		$suffix = defined( 'SCRIPT_DEBUG' ) && SCRIPT_DEBUG ? '' : '.min';

		wp_enqueue_script( 'pll_admin', plugins_url( '/js/build/admin' . $suffix . '.js', POLYLANG_ROOT_FILE ), array( 'jquery', 'wp-ajax-response', 'postbox', 'jquery-ui-selectmenu' ), POLYLANG_VERSION, true );
		wp_localize_script( 'pll_admin', 'pll_admin', array( 'dismiss_notice' => esc_html__( 'Dismiss this notice.', 'polylang' ) ) );

		wp_enqueue_style( 'pll_selectmenu', plugins_url( '/css/build/selectmenu' . $suffix . '.css', POLYLANG_ROOT_FILE ), array(), POLYLANG_VERSION );
	}

	/**
	 * Displays a notice when there are objects with no language assigned
	 *
	 * @since 1.8
	 *
	 * @return void
	 */
	public function notice_objects_with_no_lang() {
		if ( ! empty( $this->options['default_lang'] ) && $this->model->get_objects_with_no_lang( 1 ) ) {
			printf(
				'<div class="error"><p>%s <a href="%s">%s</a></p></div>',
				esc_html__( 'There are posts, pages, categories or tags without language.', 'polylang' ),
				esc_url( wp_nonce_url( '?page=mlang&pll_action=content-default-lang&noheader=true', 'content-default-lang' ) ),
				esc_html__( 'You can set them all to the default language.', 'polylang' )
			);
		}
	}

	/**
	 * Redirects to language page ( current active tab )
	 * saves error messages in a transient for reuse in redirected page
	 *
	 * @since 1.5
	 *
	 * @param array $args query arguments to add to the url
	 * @return void
	 */
	public static function redirect( $args = array() ) {
		$errors = get_settings_errors();
		if ( ! empty( $errors ) ) {
			set_transient( 'settings_errors', $errors, 30 );
			$args['settings-updated'] = 1;
		}
		// Remove possible 'pll_action' and 'lang' query args from the referer before redirecting
		wp_safe_redirect( add_query_arg( $args, remove_query_arg( array( 'pll_action', 'lang' ), wp_get_referer() ) ) );
		exit;
	}

	/**
	 * Get the list of predefined languages
	 *
	 * @since 2.3
	 *
	 * @return string[] {
	 *   @type string $code     ISO 639-1 language code.
	 *   @type string $locale   WordPress locale.
	 *   @type string $name     Native language name.
	 *   @type string $dir      Text direction: 'ltr' or 'rtl'.
	 *   @type string $flag     Flag code, generally the country code.
	 *   @type string $w3c      W3C locale.
	 *   @type string $facebook Facebook locale.
	 * }
	 */
	public static function get_predefined_languages() {
		require_once ABSPATH . 'wp-admin/includes/translation-install.php';

		$languages    = include __DIR__ . '/languages.php';
		$translations = wp_get_available_translations();

		// Keep only languages with existing WP language pack
		// Unless the transient has expired and we don't have an internet connection to refresh it
		if ( ! empty( $translations ) ) {
			$translations['en_US'] = ''; // Languages packs don't include en_US
			$languages = array_intersect_key( $languages, $translations );
		}

		/**
		 * Filter the list of predefined languages
		 *
		 * @since 1.7.10
		 * @since 2.3 The languages arrays use associative keys instead of numerical keys
		 * @see https://github.com/polylang/polylang/blob/2.8.2/settings/languages.php the list of predefined languages
		 *
		 * @param array $languages
		 */
		$languages = apply_filters( 'pll_predefined_languages', $languages );

		// Keep only languages with all necessary informations
		foreach ( $languages as $k => $lang ) {
			if ( ! isset( $lang['code'], $lang['locale'], $lang['name'], $lang['dir'], $lang['flag'] ) ) {
				unset( $languages[ $k ] );
			}
		}

		return $languages;
	}
}
