<?php

/**

 * Widget API: WP_Widget_Custom_HTML class

 *

 * @package WordPress

 * @subpackage Widgets

 * @since 4.8.1

 */

/**

 * Core class used to implement a Custom HTML widget.

 *

 * @since 4.8.1

 *

 * @see WP_Widget

 */

class WP_Widget_Custom_HTML extends WP_Widget {

	/**

	 * Whether or not the widget has been registered yet.

	 *

	 * @since 4.9.0

	 * @var bool

	 */

	protected $registered = false;

	/**

	 * Default instance.

	 *

	 * @since 4.8.1

	 * @var array

	 */

	protected $default_instance = array(

		'title'   => '',

		'content' => '',

	);

	/**

	 * Sets up a new Custom HTML widget instance.

	 *

	 * @since 4.8.1

	 */

	public function __construct() {

		$widget_ops  = array(

			'classname'                   => 'widget_custom_html',

			'description'                 => __( 'Arbitrary HTML code.' ),

			'customize_selective_refresh' => true,

			'show_instance_in_rest'       => true,

		);

		$control_ops = array(

			'width'  => 400,

			'height' => 350,

		);

		parent::__construct( 'custom_html', __( 'Custom HTML' ), $widget_ops, $control_ops );

	}

	/**

	 * Add hooks for enqueueing assets when registering all widget instances of this widget class.

	 *

	 * @since 4.9.0

	 *

	 * @param int $number Optional. The unique order number of this widget instance

	 *                    compared to other instances of the same class. Default -1.

	 */

	public function _register_one( $number = -1 ) {

		parent::_register_one( $number );

		if ( $this->registered ) {

			return;

		}

		$this->registered = true;

		/*

		 * Note that the widgets component in the customizer will also do

		 * the 'admin_print_scripts-widgets.php' action in WP_Customize_Widgets::print_scripts().

		 */

		add_action( 'admin_print_scripts-widgets.php', array( $this, 'enqueue_admin_scripts' ) );

		/*

		 * Note that the widgets component in the customizer will also do

		 * the 'admin_footer-widgets.php' action in WP_Customize_Widgets::print_footer_scripts().

		 */

		add_action( 'admin_footer-widgets.php', array( 'WP_Widget_Custom_HTML', 'render_control_template_scripts' ) );

		// Note this action is used to ensure the help text is added to the end.

		add_action( 'admin_head-widgets.php', array( 'WP_Widget_Custom_HTML', 'add_help_text' ) );

	}

	/**

	 * Filters gallery shortcode attributes.

	 *

	 * Prevents all of a site's attachments from being shown in a gallery displayed on a

	 * non-singular template where a $post context is not available.

	 *

	 * @since 4.9.0

	 *

	 * @param array $attrs Attributes.

	 * @return array Attributes.

	 */

	public function _filter_gallery_shortcode_attrs( $attrs ) {

		if ( ! is_singular() && empty( $attrs['id'] ) && empty( $attrs['include'] ) ) {

			$attrs['id'] = -1;

		}

		return $attrs;

	}

	/**

	 * Outputs the content for the current Custom HTML widget instance.

	 *

	 * @since 4.8.1

	 *

	 * @global WP_Post $post Global post object.

	 *

	 * @param array $args     Display arguments including 'before_title', 'after_title',

	 *                        'before_widget', and 'after_widget'.

	 * @param array $instance Settings for the current Custom HTML widget instance.

	 */

	public function widget( $args, $instance ) {

		global $post;

		// Override global $post so filters (and shortcodes) apply in a consistent context.

		$original_post = $post;

		if ( is_singular() ) {

			// Make sure post is always the queried object on singular queries (not from another sub-query that failed to clean up the global $post).

			$post = get_queried_object();

		} else {

			// Nullify the $post global during widget rendering to prevent shortcodes from running with the unexpected context on archive queries.

			$post = null;

		}

		// Prevent dumping out all attachments from the media library.

		add_filter( 'shortcode_atts_gallery', array( $this, '_filter_gallery_shortcode_attrs' ) );

		$instance = array_merge( $this->default_instance, $instance );

		/** This filter is documented in wp-includes/widgets/class-wp-widget-pages.php */

		$title = apply_filters( 'widget_title', $instance['title'], $instance, $this->id_base );

		// Prepare instance data that looks like a normal Text widget.

		$simulated_text_widget_instance = array_merge(

			$instance,

			array(

				'text'   => isset( $instance['content'] ) ? $instance['content'] : '',

				'filter' => false, // Because wpautop is not applied.

				'visual' => false, // Because it wasn't created in TinyMCE.

			)

		);

		unset( $simulated_text_widget_instance['content'] ); // Was moved to 'text' prop.

		/** This filter is documented in wp-includes/widgets/class-wp-widget-text.php */

		$content = apply_filters( 'widget_text', $instance['content'], $simulated_text_widget_instance, $this );

		/**

		 * Filters the content of the Custom HTML widget.

		 *

		 * @since 4.8.1

		 *

		 * @param string                $content  The widget content.

		 * @param array                 $instance Array of settings for the current widget.

		 * @param WP_Widget_Custom_HTML $widget   Current Custom HTML widget instance.

		 */

		$content = apply_filters( 'widget_custom_html_content', $content, $instance, $this );

		// Restore post global.

		$post = $original_post;

		remove_filter( 'shortcode_atts_gallery', array( $this, '_filter_gallery_shortcode_attrs' ) );

		// Inject the Text widget's container class name alongside this widget's class name for theme styling compatibility.

		$args['before_widget'] = preg_replace( '/(?<=\sclass=["\'])/', 'widget_text ', $args['before_widget'] );

		echo $args['before_widget'];

		if ( ! empty( $title ) ) {

			echo $args['before_title'] . $title . $args['after_title'];

		}

		echo '<div class="textwidget custom-html-widget">'; // The textwidget class is for theme styling compatibility.

		echo $content;

		echo '</div>';

		echo $args['after_widget'];

	}

	/**

	 * Handles updating settings for the current Custom HTML widget instance.

	 *

	 * @since 4.8.1

	 *

	 * @param array $new_instance New settings for this instance as input by the user via

	 *                            WP_Widget::form().

	 * @param array $old_instance Old settings for this instance.

	 * @return array Settings to save or bool false to cancel saving.

	 */

	public function update( $new_instance, $old_instance ) {

		$instance          = array_merge( $this->default_instance, $old_instance );

		$instance['title'] = sanitize_text_field( $new_instance['title'] );

		if ( current_user_can( 'unfiltered_html' ) ) {

			$instance['content'] = $new_instance['content'];

		} else {

			$instance['content'] = wp_kses_post( $new_instance['content'] );

		}

		return $instance;

	}

	/**

	 * Loads the required scripts and styles for the widget control.

	 *

	 * @since 4.9.0

	 */

	public function enqueue_admin_scripts() {

		$settings = wp_enqueue_code_editor(

			array(

				'type'       => 'text/html',

				'codemirror' => array(

					'indentUnit' => 2,

					'tabSize'    => 2,

				),

			)

		);

		wp_enqueue_script( 'custom-html-widgets' );

		wp_add_inline_script( 'custom-html-widgets', sprintf( 'wp.customHtmlWidgets.idBases.push( %s );', wp_json_encode( $this->id_base ) ) );

		if ( empty( $settings ) ) {

			$settings = array(

				'disabled' => true,

			);

		}

		wp_add_inline_script( 'custom-html-widgets', sprintf( 'wp.customHtmlWidgets.init( %s );', wp_json_encode( $settings ) ), 'after' );

		$l10n = array(

			'errorNotice' => array(

				/* translators: %d: Error count. */

				'singular' => _n( 'There is %d error which must be fixed before you can save.', 'There are %d errors which must be fixed before you can save.', 1 ),

				/* translators: %d: Error count. */

				'plural'   => _n( 'There is %d error which must be fixed before you can save.', 'There are %d errors which must be fixed before you can save.', 2 ),

				// @todo This is lacking, as some languages have a dedicated dual form. For proper handling of plurals in JS, see #20491.

			),

		);

		wp_add_inline_script( 'custom-html-widgets', sprintf( 'jQuery.extend( wp.customHtmlWidgets.l10n, %s );', wp_json_encode( $l10n ) ), 'after' );

	}

	/**

	 * Outputs the Custom HTML widget settings form.

	 *

	 * @since 4.8.1

	 * @since 4.9.0 The form contains only hidden sync inputs. For the control UI, see `WP_Widget_Custom_HTML::render_control_template_scripts()`.

	 *

	 * @see WP_Widget_Custom_HTML::render_control_template_scripts()

	 *

	 * @param array $instance Current instance.

	 */

	public function form( $instance ) {

		$instance = wp_parse_args( (array) $instance, $this->default_instance );

		?>

		<input id="<?php echo $this->get_field_id( 'title' ); ?>" name="<?php echo $this->get_field_name( 'title' ); ?>" class="title sync-input" type="hidden" value="<?php echo esc_attr( $instance['title'] ); ?>" />

		<textarea id="<?php echo $this->get_field_id( 'content' ); ?>" name="<?php echo $this->get_field_name( 'content' ); ?>" class="content sync-input" hidden><?php echo esc_textarea( $instance['content'] ); ?></textarea>

		<?php

	}

	/**

	 * Render form template scripts.

	 *

	 * @since 4.9.0

	 */

	public static function render_control_template_scripts() {

		?>

		<script type="text/html" id="tmpl-widget-custom-html-control-fields">

			<# var elementIdPrefix = 'el' + String( Math.random() ).replace( /\D/g, '' ) + '_' #>

			<p>

				<label for="{{ elementIdPrefix }}title"><?php esc_html_e( 'Title:' ); ?></label>

				<input id="{{ elementIdPrefix }}title" type="text" class="widefat title">

			</p>

			<p>

				<label for="{{ elementIdPrefix }}content" id="{{ elementIdPrefix }}content-label"><?php esc_html_e( 'Content:' ); ?></label>

				<textarea id="{{ elementIdPrefix }}content" class="widefat code content" rows="16" cols="20"></textarea>

			</p>

			<?php if ( ! current_user_can( 'unfiltered_html' ) ) : ?>

				<?php

				$probably_unsafe_html = array( 'script', 'iframe', 'form', 'input', 'style' );

				$allowed_html         = wp_kses_allowed_html( 'post' );

				$disallowed_html      = array_diff( $probably_unsafe_html, array_keys( $allowed_html ) );

				?>

				<?php if ( ! empty( $disallowed_html ) ) : ?>

					<# if ( data.codeEditorDisabled ) { #>

						<p>

							<?php _e( 'Some HTML tags are not permitted, including:' ); ?>

							<code><?php echo implode( '</code>, <code>', $disallowed_html ); ?></code>

						</p>

					<# } #>

				<?php endif; ?>

			<?php endif; ?>

			<div class="code-editor-error-container"></div>

		</script>

		<?php

	}

	/**

	 * Add help text to widgets admin screen.

	 *

	 * @since 4.9.0

	 */

	public static function add_help_text() {

		$screen = get_current_screen();

		$content  = '<p>';

		$content .= __( 'Use the Custom HTML widget to add arbitrary HTML code to your widget areas.' );

		$content .= '</p>';

		if ( 'false' !== wp_get_current_user()->syntax_highlighting ) {

			$content .= '<p>';

			$content .= sprintf(

				/* translators: 1: Link to user profile, 2: Additional link attributes, 3: Accessibility text. */

				__( 'The edit field automatically highlights code syntax. You can disable this in your <a href="%1$s" %2$s>user profile%3$s</a> to work in plain text mode.' ),

				esc_url( get_edit_profile_url() ),

				'class="external-link" target="_blank"',

				sprintf(

					'<span class="screen-reader-text"> %s</span>',

					/* translators: Hidden accessibility text. */

					__( '(opens in a new tab)' )

				)

			);

			$content .= '</p>';

			$content .= '<p id="editor-keyboard-trap-help-1">' . __( 'When using a keyboard to navigate:' ) . '</p>';

			$content .= '<ul>';

			$content .= '<li id="editor-keyboard-trap-help-2">' . __( 'In the editing area, the Tab key enters a tab character.' ) . '</li>';

			$content .= '<li id="editor-keyboard-trap-help-3">' . __( 'To move away from this area, press the Esc key followed by the Tab key.' ) . '</li>';

			$content .= '<li id="editor-keyboard-trap-help-4">' . __( 'Screen reader users: when in forms mode, you may need to press the Esc key twice.' ) . '</li>';

			$content .= '</ul>';

		}

		$screen->add_help_tab(

			array(

				'id'      => 'custom_html_widget',

				'title'   => __( 'Custom HTML Widget' ),

				'content' => $content,

			)

		);

	}

}