1094: Transform CSS selectors according to sanitizer HTML element to AMP component conversions

assets/css/amp-default.css

@@ -1,4 +1,4 @@
-.amp-wp-unknown-size img {
+.amp-wp-unknown-size .i-amphtml-replaced-content {
 	/** Worst case scenario when we can't figure out dimensions for an image. **/
 	/** Force the image into a box of fixed dimensions and use object-fit to scale. **/
 	object-fit: contain;

assets/js/amp-editor-blocks.js

@@ -731,7 +731,7 @@ var ampEditorBlocks = ( function() { // eslint-disable-line no-unused-vars
 					return element;
 				}
 			} else if ( ! component.hasGalleryShortcodeCarouselAttribute( attributes.text || '' ) ) {
-				// Add amp-carousel=false attribut to the shortcode.
+				// Add amp-carousel=false attribute to the shortcode.
 				text = attributes.text.replace( '[gallery', '[gallery amp-carousel=false' );
 			} else {
 				text = attributes.text;

includes/sanitizers/class-amp-audio-sanitizer.php

@@ -20,6 +20,17 @@ class AMP_Audio_Sanitizer extends AMP_Base_Sanitizer {
 	 */
 	public static $tag = 'audio';
 
+	/**
+	 * Get mapping of HTML selectors to the AMP component selectors which they may be converted into.
+	 *
+	 * @return array Mapping.
+	 */
+	public function get_selector_conversion_mapping() {
+		return array(
+			'audio' => array( 'amp-audio' ),
+		);
+	}
+
 	/**
 	 * Sanitize the <audio> elements from the HTML contained in this instance's DOMDocument.
 	 *

includes/sanitizers/class-amp-base-sanitizer.php

@@ -23,6 +23,7 @@ abstract class AMP_Base_Sanitizer {
 	 * Value for <amp-image-lightbox> ID.
 	 *
 	 * @since 1.0
+	 * @todo Move to AMP_Img_Sanitizer?
 	 *
 	 * @const string
 	 */
@@ -121,11 +122,41 @@ public function __construct( $dom, $args = array() ) {
 		}
 	}
 
+	/**
+	 * Get mapping of HTML selectors to the AMP component selectors which they may be converted into.
+	 *
+	 * @return array Mapping.
+	 */
+	public function get_selector_conversion_mapping() {
+		return array();
+	}
+
+	/**
+	 * Run logic before any sanitizers are run.
+	 *
+	 * After the sanitizers are instantiated but before calling sanitize on each of them, this
+	 * method is called with list of all the instantiated sanitizers.
+	 *
+	 * @todo Call this init?
+	 *
+	 * @param AMP_Base_Sanitizer[] $sanitizers Sanitizers.
+	 */
+	public function before_sanitize( $sanitizers ) {}
+
 	/**
 	 * Sanitize the HTML contained in the DOMDocument received by the constructor
 	 */
 	abstract public function sanitize();
 
+	/**
+	 * Run logic after all sanitizers are finished.
+	 *
+	 * @todo Do we even need this?
+	 *
+	 * @param AMP_Base_Sanitizer[] $sanitizers Sanitizers.
+	 */
+	public function after_sanitize( $sanitizers ) {}
+
 	/**
 	 * Return array of values that would be valid as an HTML `script` element.
 	 *
@@ -444,6 +475,8 @@ public function get_data_amp_attributes( $node ) {
 			if ( isset( $parent_attributes['data-amp-noloading'] ) && true === filter_var( $parent_attributes['data-amp-noloading'], FILTER_VALIDATE_BOOLEAN ) ) {
 				$attributes['noloading'] = $parent_attributes['data-amp-noloading'];
 			}
+
+			// @todo Move to AMP_Img_Sanitizer subclassed method?
 			if ( isset( $parent_attributes['data-amp-lightbox'] ) && true === filter_var( $parent_attributes['data-amp-lightbox'], FILTER_VALIDATE_BOOLEAN ) ) {
 				$attributes['lightbox'] = true;
 			}
@@ -466,6 +499,7 @@ public function filter_data_amp_attributes( $attributes, $amp_data ) {
 		if ( isset( $amp_data['noloading'] ) ) {
 			$attributes['data-amp-noloading'] = '';
 		}
+		// @todo Move lightbox condition to subclassed method of AMP_Img_Sanitizer.
 		if ( isset( $amp_data['lightbox'] ) ) {
 			$attributes['data-amp-lightbox'] = '';
 			$attributes['on']                = 'tap:' . self::AMP_IMAGE_LIGHTBOX_ID;
@@ -514,6 +548,8 @@ public function filter_attachment_layout_attributes( $node, $new_attributes, $la
 
 	/**
 	 * Add <amp-image-lightbox> element to body tag if it doesn't exist yet.
+	 *
+	 * @todo Move this to AMP_Img_Sanitizer?
 	 */
 	public function maybe_add_amp_image_lightbox_node() {
 

includes/sanitizers/class-amp-iframe-sanitizer.php

@@ -48,6 +48,19 @@ class AMP_Iframe_Sanitizer extends AMP_Base_Sanitizer {
 		'add_placeholder' => false,
 	);
 
+	/**
+	 * Get mapping of HTML selectors to the AMP component selectors which they may be converted into.
+	 *
+	 * @return array Mapping.
+	 */
+	public function get_selector_conversion_mapping() {
+		return array(
+			'iframe' => array(
+				'amp-iframe',
+			),
+		);
+	}
+
 	/**
 	 * Sanitize the <iframe> elements from the HTML contained in this instance's DOMDocument.
 	 *
@@ -189,7 +202,7 @@ private function filter_attributes( $attributes ) {
 	private function build_placeholder( $parent_attributes ) {
 		$placeholder_node = AMP_DOM_Utils::create_node( $this->dom, 'div', array(
 			'placeholder' => '',
-			'class' => 'amp-wp-iframe-placeholder',
+			'class'       => 'amp-wp-iframe-placeholder',
 		) );
 
 		return $placeholder_node;

includes/sanitizers/class-amp-img-sanitizer.php

@@ -46,6 +46,20 @@ class AMP_Img_Sanitizer extends AMP_Base_Sanitizer {
 	 */
 	private static $anim_extension = '.gif';
 
+	/**
+	 * Get mapping of HTML selectors to the AMP component selectors which they may be converted into.
+	 *
+	 * @return array Mapping.
+	 */
+	public function get_selector_conversion_mapping() {
+		return array(
+			'img' => array(
+				'amp-img',
+				'amp-anim',
+			),
+		);
+	}
+
 	/**
 	 * Sanitize the <img> elements from the HTML contained in this instance's DOMDocument.
 	 *

includes/sanitizers/class-amp-playbuzz-sanitizer.php

@@ -40,6 +40,18 @@ class AMP_Playbuzz_Sanitizer extends AMP_Base_Sanitizer {
 	 */
 	private static $height = '500';
 
+	/**
+	 * Get mapping of HTML selectors to the AMP component selectors which they may be converted into.
+	 *
+	 * @return array Mapping.
+	 */
+	public function get_selector_conversion_mapping() {
+		return array(
+			'div.pb_feed' => array( 'amp-playbuzz' ),
+			'.pb_feed'    => array( 'amp-playbuzz' ),
+		);
+	}
+
 	/**
 	 * Sanitize the Playbuzz elements from the HTML contained in this instance's DOMDocument.
 	 *

includes/sanitizers/class-amp-style-sanitizer.php

@@ -182,6 +182,13 @@ class AMP_Style_Sanitizer extends AMP_Base_Sanitizer {
 	 */
 	private $processed_imported_stylesheet_urls = array();
 
+	/**
+	 * Mapping of HTML element selectors to AMP selector elements.
+	 *
+	 * @var array
+	 */
+	private $selector_mappings = array();
+
 	/**
 	 * Get error codes that can be raised during parsing of CSS.
 	 *
@@ -308,6 +315,30 @@ private function get_used_tag_names() {
 		return $this->used_tag_names;
 	}
 
+	/**
+	 * Run logic before any sanitizers are run.
+	 *
+	 * After the sanitizers are instantiated but before calling sanitize on each of them, this
+	 * method is called with list of all the instantiated sanitizers.
+	 *
+	 * @param AMP_Base_Sanitizer[] $sanitizers Sanitizers.
+	 */
+	public function before_sanitize( $sanitizers ) {
+		parent::before_sanitize( $sanitizers );
+
+		foreach ( $sanitizers as $sanitizer ) {
+			foreach ( $sanitizer->get_selector_conversion_mapping() as $html_selectors => $amp_selectors ) {
+				if ( ! isset( $this->selector_mappings[ $html_selectors ] ) ) {
+					$this->selector_mappings[ $html_selectors ] = $amp_selectors;
+				} else {
+					$this->selector_mappings[ $html_selectors ] = array_unique(
+						array_merge( $this->selector_mappings[ $html_selectors ], $amp_selectors )
+					);
+				}
+			}
+		}
+	}
+
 	/**
 	 * Sanitize CSS styles within the HTML contained in this instance's DOMDocument.
 	 *
@@ -647,7 +678,7 @@ private function fetch_external_stylesheet( $url ) {
 	private function process_stylesheet( $stylesheet, $options = array() ) {
 		$parsed      = null;
 		$cache_key   = null;
-		$cache_group = 'amp-parsed-stylesheet-v6';
+		$cache_group = 'amp-parsed-stylesheet-v7';
 
 		$cache_impacting_options = array_merge(
 			wp_array_slice_assoc(
@@ -1236,6 +1267,10 @@ private function real_path_urls( $urls, $stylesheet_url ) {
 	private function process_css_declaration_block( RuleSet $ruleset, CSSList $css_list, $options ) {
 		$results = array();
 
+		if ( $ruleset instanceof DeclarationBlock ) {
+			$this->ampify_ruleset_selectors( $ruleset );
+		}
+
 		// Remove disallowed properties.
 		if ( ! empty( $options['property_whitelist'] ) ) {
 			$properties = $ruleset->getRules();
@@ -1754,6 +1789,40 @@ private function finalize_styles() {
 		}
 	}
 
+	/**
+	 * Convert CSS selectors.
+	 *
+	 * @param DeclarationBlock $ruleset Ruleset.
+	 */
+	private function ampify_ruleset_selectors( $ruleset ) {
+		$selectors    = array();
+		$replacements = 0;
+		foreach ( $ruleset->getSelectors() as $old_selector ) {
+			$edited_selectors = array( $old_selector->getSelector() );
+			foreach ( $this->selector_mappings as $html_selector => $amp_selectors ) { // Note: The $selector_mappings array contains ~6 items.
+				$html_pattern = '/(?<=^|[^a-z0-9_-])' . preg_quote( $html_selector ) . '(?=$|[^a-z0-9_-])/i';
+				foreach ( $edited_selectors as &$edited_selector ) { // Note: The $edited_selectors array contains only item in the normal case.
+					$original_selector = $edited_selector;
+					$amp_selector      = array_shift( $amp_selectors );
+					$edited_selector   = preg_replace( $html_pattern, $amp_selector, $edited_selector, -1, $count );
+					if ( ! $count ) {
+						continue;
+					}
+					$replacements += $count;
+					while ( ! empty( $amp_selectors ) ) { // Note: This array contains only a couple items.
+						$amp_selector       = array_shift( $amp_selectors );
+						$edited_selectors[] = preg_replace( $html_pattern, $amp_selector, $original_selector, -1, $count );
+					}
+				}
+			}
+			$selectors = array_merge( $selectors, $edited_selectors );
+		}
+
+		if ( $replacements > 0 ) {
+			$ruleset->setSelectors( $selectors );
+		}
+	}
+
 	/**
 	 * Finalize a stylesheet set (amp-custom or amp-keyframes).
 	 *

includes/sanitizers/class-amp-video-sanitizer.php

@@ -32,6 +32,17 @@ class AMP_Video_Sanitizer extends AMP_Base_Sanitizer {
 	 */
 	public static $tag = 'video';
 
+	/**
+	 * Get mapping of HTML selectors to the AMP component selectors which they may be converted into.
+	 *
+	 * @return array Mapping.
+	 */
+	public function get_selector_conversion_mapping() {
+		return array(
+			'video' => array( 'amp-video' ),
+		);
+	}
+
 	/**
 	 * Sanitize the <video> elements from the HTML contained in this instance's DOMDocument.
 	 *

includes/templates/class-amp-content-sanitizer.php

@@ -63,8 +63,16 @@ public static function sanitize_document( &$dom, $sanitizer_classes, $args ) {
 
 		$return_styles = ! empty( $args['return_styles'] );
 		unset( $args['return_styles'] );
+
+		/**
+		 * Sanitizers.
+		 *
+		 * @var AMP_Base_Sanitizer[] $sanitizers
+		 */
+		$sanitizers = array();
+
+		// Instantiate the sanitizers.
 		foreach ( $sanitizer_classes as $sanitizer_class => $sanitizer_args ) {
-			$sanitize_class_start = microtime( true );
 			if ( ! class_exists( $sanitizer_class ) ) {
 				/* translators: %s is sanitizer class */
 				_doing_it_wrong( __METHOD__, sprintf( esc_html__( 'Sanitizer (%s) class does not exist', 'amp' ), esc_html( $sanitizer_class ) ), '0.4.1' );
@@ -84,6 +92,18 @@ public static function sanitize_document( &$dom, $sanitizer_classes, $args ) {
 				continue;
 			}
 
+			$sanitizers[ $sanitizer_class ] = $sanitizer;
+		}
+
+		// Let the sanitizers know about each other prior to sanitizing.
+		foreach ( $sanitizers as $sanitizer ) {
+			$sanitizer->before_sanitize( $sanitizers );
+		}
+
+		// Sanitize.
+		foreach ( $sanitizers as $sanitizer ) {
+			$sanitize_class_start = microtime( true );
+
 			$sanitizer->sanitize();
 
 			$scripts = array_merge( $scripts, $sanitizer->get_scripts() );
@@ -96,6 +116,11 @@ public static function sanitize_document( &$dom, $sanitizer_classes, $args ) {
 			AMP_Response_Headers::send_server_timing( 'amp_sanitize', -$sanitize_class_start, $sanitizer_class );
 		}
 
+		// Let the sanitizers.
+		foreach ( $sanitizers as $sanitizer ) {
+			$sanitizer->after_sanitize( $sanitizers );
+		}
+
 		return compact( 'scripts', 'styles', 'stylesheets' );
 	}
 }

includes/utils/class-amp-dom-utils.php

@@ -473,7 +473,7 @@ public static function create_node( $dom, $tag, $attributes ) {
 	 *
 	 * @since 0.2
 	 *
-	 * @param DOMNode $node Represents an HTML element for which to extract attributes.
+	 * @param DOMElement $node Represents an HTML element for which to extract attributes.
 	 *
 	 * @return string[] The attributes for the passed node, or an
 	 *                  empty array if it has no attributes.