1<?php
  2/**
  3 * Server-side rendering of the `core/image` block.
  4 *
  5 * @package WordPress
  6 */
  7
  8/**
  9 * Renders the `core/image` block on the server,
 10 * adding a data-id attribute to the element if core/gallery has added on pre-render.
 11 *
 12 * @since 5.9.0
 13 *
 14 * @param array    $attributes The block attributes.
 15 * @param string   $content    The block content.
 16 * @param WP_Block $block      The block object.
 17 *
 18 * @return string The block content with the data-id attribute added.
 19 */
 20function render_block_core_image( $attributes, $content, $block ) {
 21	if ( false === stripos( $content, '<img' ) ) {
 22		return '';
 23	}
 24
 25	$processor = new class( $content ) extends WP_HTML_Tag_Processor {
 26		/**
 27		 * Return input span for an empty FIGCAPTION element.
 28		 *
 29		 * Returns span of input for an empty FIGCAPTION, if currently matched on a
 30		 * FIGCAPTION opening tag and if the element is properly closed and empty.
 31		 *
 32		 * @since 6.9.0
 33		 *
 34		 * @return WP_HTML_Span|false Span of input if the element is empty; otherwise false.
 35		 */
 36		public function block_core_image_extract_empty_figcaption_element() {
 37			$this->set_bookmark( 'here' );
 38			$opener = $this->bookmarks['here'];
 39
 40			// Allow comments within the definition of “empty.”
 41			while ( $this->next_token() && '#comment' === $this->get_token_name() ) {
 42				continue;
 43			}
 44
 45			if ( 'FIGCAPTION' !== $this->get_tag() || ! $this->is_tag_closer() ) {
 46				return false;
 47			}
 48
 49			$this->set_bookmark( 'here' );
 50			$closer = $this->bookmarks['here'];
 51
 52			return new WP_HTML_Span( $opener->start, $closer->start + $closer->length - $opener->start );
 53		}
 54	};
 55
 56	if ( ! $processor->next_tag( 'img' ) || ! $processor->get_attribute( 'src' ) ) {
 57		return '';
 58	}
 59
 60	$has_id_binding = isset( $attributes['metadata']['bindings']['id'] ) && isset( $attributes['id'] );
 61
 62	// Ensure the `wp-image-id` classname on the image block supports block bindings.
 63	if ( $has_id_binding ) {
 64		// If there's a mismatch with the 'wp-image-' class and the actual id, the id was
 65		// probably overridden by block bindings. Update it to the correct value.
 66		// See https://github.com/WordPress/gutenberg/issues/62886 for why this is needed.
 67		$id                       = $attributes['id'];
 68		$image_classnames         = $processor->get_attribute( 'class' );
 69		$class_with_binding_value = "wp-image-$id";
 70		if ( is_string( $image_classnames ) && ! str_contains( $image_classnames, $class_with_binding_value ) ) {
 71			$image_classnames = preg_replace( '/wp-image-(\d+)/', $class_with_binding_value, $image_classnames );
 72			$processor->set_attribute( 'class', $image_classnames );
 73		}
 74	}
 75
 76	// For backwards compatibility, the data-id html attribute is only set for
 77	// image blocks nested in a gallery. Detect if the image is in a gallery by
 78	// checking the data-id attribute.
 79	// See the `block_core_gallery_data_id_backcompatibility` function.
 80	if ( isset( $attributes['data-id'] ) ) {
 81		// If there's a binding for the `id`, the `id` attribute is used for the
 82		// value, since `data-id` does not support block bindings.
 83		// Else the `data-id` is used for backwards compatibility, since
 84		// third parties may be filtering its value.
 85		$data_id = $has_id_binding ? $attributes['id'] : $attributes['data-id'];
 86		$processor->set_attribute( 'data-id', $data_id );
 87	}
 88
 89	/*
 90	 * If the `caption` attribute is empty and we encounter a `<figcaption>` element,
 91	 * we take note of its span so we can remove it later.
 92	 */
 93	if ( $processor->next_tag( 'FIGCAPTION' ) && empty( $attributes['caption'] ) ) {
 94		$figcaption_span = $processor->block_core_image_extract_empty_figcaption_element();
 95	}
 96
 97	$link_destination  = isset( $attributes['linkDestination'] ) ? $attributes['linkDestination'] : 'none';
 98	$lightbox_settings = block_core_image_get_lightbox_settings( $block->parsed_block );
 99
100	/*
101	 * If the lightbox is enabled and the image is not linked, adds the filter and
102	 * the JavaScript view file.
103	 */
104	if (
105		isset( $lightbox_settings ) &&
106		'none' === $link_destination &&
107		isset( $lightbox_settings['enabled'] ) &&
108		true === $lightbox_settings['enabled']
109	) {
110		wp_enqueue_script_module( '@wordpress/block-library/image/view' );
111
112		/*
113		 * This render needs to happen in a filter with priority 15 to ensure that
114		 * it runs after the duotone filter and that duotone styles are applied to
115		 * the image in the lightbox. Lightbox has to work with any plugins that
116		 * might use filters as well. Removing this can be considered in the future
117		 * if the way the blocks are rendered changes, or if a new kind of filter is
118		 * introduced.
119		 */
120		add_filter( 'render_block_core/image', 'block_core_image_render_lightbox', 15, 2 );
121	} else {
122		/*
123		 * Remove the filter if previously added by other Image blocks.
124		 */
125		remove_filter( 'render_block_core/image', 'block_core_image_render_lightbox', 15 );
126	}
127
128	$output = $processor->get_updated_html();
129	if ( ! empty( $figcaption_span ) ) {
130		return substr( $output, 0, $figcaption_span->start ) . substr( $output, $figcaption_span->start + $figcaption_span->length );
131	}
132	return $output;
133}
134
135/**
136 * Adds the lightboxEnabled flag to the block data.
137 *
138 * This is used to determine whether the lightbox should be rendered or not.
139 *
140 * @since 6.4.0
141 *
142 * @param array $block Block data.
143 *
144 * @return array|null Filtered block data.
145 */
146function block_core_image_get_lightbox_settings( $block ) {
147	// Gets the lightbox setting from the block attributes.
148	if ( isset( $block['attrs']['lightbox'] ) ) {
149		$lightbox_settings = $block['attrs']['lightbox'];
150	}
151
152	if ( ! isset( $lightbox_settings ) ) {
153		$lightbox_settings = wp_get_global_settings( array( 'lightbox' ), array( 'block_name' => 'core/image' ) );
154
155		// If not present in global settings, check the top-level global settings.
156		//
157		// NOTE: If no block-level settings are found, the previous call to
158		// `wp_get_global_settings` will return the whole `theme.json` structure in
159		// which case we can check if the "lightbox" key is present at the top-level
160		// of the global settings and use its value.
161		if ( isset( $lightbox_settings['lightbox'] ) ) {
162			$lightbox_settings = wp_get_global_settings( array( 'lightbox' ) );
163		}
164	}
165
166	return $lightbox_settings ?? null;
167}
168
169/**
170 * Adds the directives and layout needed for the lightbox behavior.
171 *
172 * @since 6.4.0
173 *
174 * @param string $block_content Rendered block content.
175 * @param array  $block         Block object.
176 *
177 * @return string Filtered block content.
178 */
179function block_core_image_render_lightbox( $block_content, $block ) {
180	/*
181	 * If there's no IMG tag in the block then return the given block content
182	 * as-is. There's nothing that this code can knowingly modify to add the
183	 * lightbox behavior.
184	 */
185	$processor = new WP_HTML_Tag_Processor( $block_content );
186	if ( $processor->next_tag( 'figure' ) ) {
187		$processor->set_bookmark( 'figure' );
188	}
189	if ( ! $processor->next_tag( 'img' ) ) {
190		return $block_content;
191	}
192
193	$alt               = $processor->get_attribute( 'alt' );
194	$img_uploaded_src  = $processor->get_attribute( 'src' );
195	$img_class_names   = $processor->get_attribute( 'class' );
196	$img_styles        = $processor->get_attribute( 'style' );
197	$img_width         = 'none';
198	$img_height        = 'none';
199	$aria_label        = __( 'Enlarge' );
200	$dialog_aria_label = __( 'Enlarged image' );
201
202	if ( isset( $block['attrs']['id'] ) ) {
203		$img_uploaded_src = wp_get_attachment_url( $block['attrs']['id'] );
204		$img_metadata     = wp_get_attachment_metadata( $block['attrs']['id'] );
205		$img_width        = $img_metadata['width'] ?? 'none';
206		$img_height       = $img_metadata['height'] ?? 'none';
207	}
208
209	// Figure.
210	$processor->seek( 'figure' );
211	$figure_class_names = $processor->get_attribute( 'class' );
212	$figure_styles      = $processor->get_attribute( 'style' );
213
214	// Create unique id and set the image metadata in the state.
215	$unique_image_id = uniqid();
216
217	wp_interactivity_state(
218		'core/image',
219		array(
220			'metadata' => array(
221				$unique_image_id => array(
222					'uploadedSrc'      => $img_uploaded_src,
223					'figureClassNames' => $figure_class_names,
224					'figureStyles'     => $figure_styles,
225					'imgClassNames'    => $img_class_names,
226					'imgStyles'        => $img_styles,
227					'targetWidth'      => $img_width,
228					'targetHeight'     => $img_height,
229					'scaleAttr'        => $block['attrs']['scale'] ?? false,
230					'ariaLabel'        => $dialog_aria_label,
231					'alt'              => $alt,
232				),
233			),
234		)
235	);
236
237	$processor->add_class( 'wp-lightbox-container' );
238	$processor->set_attribute( 'data-wp-interactive', 'core/image' );
239	$processor->set_attribute(
240		'data-wp-context',
241		wp_json_encode(
242			array(
243				'imageId' => $unique_image_id,
244			),
245			JSON_HEX_TAG | JSON_HEX_APOS | JSON_HEX_QUOT | JSON_HEX_AMP
246		)
247	);
248	$processor->set_attribute( 'data-wp-key', $unique_image_id );
249
250	// Image.
251	$processor->next_tag( 'img' );
252	$processor->set_attribute( 'data-wp-init', 'callbacks.setButtonStyles' );
253	$processor->set_attribute( 'data-wp-on--load', 'callbacks.setButtonStyles' );
254	$processor->set_attribute( 'data-wp-on-window--resize', 'callbacks.setButtonStyles' );
255	// Sets an event callback on the `img` because the `figure` element can also
256	// contain a caption, and we don't want to trigger the lightbox when the
257	// caption is clicked.
258	$processor->set_attribute( 'data-wp-on--click', 'actions.showLightbox' );
259	$processor->set_attribute( 'data-wp-class--hide', 'state.isContentHidden' );
260	$processor->set_attribute( 'data-wp-class--show', 'state.isContentVisible' );
261
262	$body_content = $processor->get_updated_html();
263
264	// Adds a button alongside image in the body content.
265	$img = null;
266	preg_match( '/<img[^>]+>/', $body_content, $img );
267
268	$button =
269		$img[0]
270		. '<button
271			class="lightbox-trigger"
272			type="button"
273			aria-haspopup="dialog"
274			aria-label="' . esc_attr( $aria_label ) . '"
275			data-wp-init="callbacks.initTriggerButton"
276			data-wp-on--click="actions.showLightbox"
277			data-wp-style--right="state.imageButtonRight"
278			data-wp-style--top="state.imageButtonTop"
279		>
280			<svg xmlns="http://www.w3.org/2000/svg" width="12" height="12" fill="none" viewBox="0 0 12 12">
281				<path fill="#fff" d="M2 0a2 2 0 0 0-2 2v2h1.5V2a.5.5 0 0 1 .5-.5h2V0H2Zm2 10.5H2a.5.5 0 0 1-.5-.5V8H0v2a2 2 0 0 0 2 2h2v-1.5ZM8 12v-1.5h2a.5.5 0 0 0 .5-.5V8H12v2a2 2 0 0 1-2 2H8Zm2-12a2 2 0 0 1 2 2v2h-1.5V2a.5.5 0 0 0-.5-.5H8V0h2Z" />
282			</svg>
283		</button>';
284
285	$body_content = preg_replace( '/<img[^>]+>/', $button, $body_content );
286
287	add_action( 'wp_footer', 'block_core_image_print_lightbox_overlay' );
288
289	return $body_content;
290}
291
292/**
293 * @since 6.5.0
294 */
295function block_core_image_print_lightbox_overlay() {
296	$close_button_label = esc_attr__( 'Close' );
297
298	// If the current theme does NOT have a `theme.json`, or the colors are not
299	// defined, it needs to set the background color & close button color to some
300	// default values because it can't get them from the Global Styles.
301	$background_color   = '#fff';
302	$close_button_color = '#000';
303	if ( wp_theme_has_theme_json() ) {
304		$global_styles_color = wp_get_global_styles( array( 'color' ) );
305		if ( ! empty( $global_styles_color['background'] ) ) {
306			$background_color = esc_attr( $global_styles_color['background'] );
307		}
308		if ( ! empty( $global_styles_color['text'] ) ) {
309			$close_button_color = esc_attr( $global_styles_color['text'] );
310		}
311	}
312
313	echo <<<HTML
314		<div
315			class="wp-lightbox-overlay zoom"
316			data-wp-interactive="core/image"
317			data-wp-router-region='{ "id": "core/image-overlay", "attachTo": "body" }'
318			data-wp-key="wp-lightbox-overlay"
319			data-wp-context='{}'
320			data-wp-bind--role="state.roleAttribute"
321			data-wp-bind--aria-label="state.currentImage.ariaLabel"
322			data-wp-bind--aria-modal="state.ariaModal"
323			data-wp-class--active="state.overlayEnabled"
324			data-wp-class--show-closing-animation="state.overlayOpened"
325			data-wp-watch="callbacks.setOverlayFocus"
326			data-wp-on--keydown="actions.handleKeydown"
327			data-wp-on--touchstart="actions.handleTouchStart"
328			data-wp-on--touchmove="actions.handleTouchMove"
329			data-wp-on--touchend="actions.handleTouchEnd"
330			data-wp-on--click="actions.hideLightbox"
331			data-wp-on-window--resize="callbacks.setOverlayStyles"
332			data-wp-on-window--scroll="actions.handleScroll"
333			data-wp-bind--style="state.overlayStyles"
334			tabindex="-1"
335			>
336				<button type="button" aria-label="$close_button_label" style="fill: $close_button_color" class="close-button">
337					<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" width="20" height="20" aria-hidden="true" focusable="false"><path d="m13.06 12 6.47-6.47-1.06-1.06L12 10.94 5.53 4.47 4.47 5.53 10.94 12l-6.47 6.47 1.06 1.06L12 13.06l6.47 6.47 1.06-1.06L13.06 12Z"></path></svg>
338				</button>
339				<div class="lightbox-image-container">
340					<figure data-wp-bind--class="state.currentImage.figureClassNames" data-wp-bind--style="state.figureStyles">
341						<img data-wp-bind--alt="state.currentImage.alt" data-wp-bind--class="state.currentImage.imgClassNames" data-wp-bind--style="state.imgStyles" data-wp-bind--src="state.currentImage.currentSrc">
342					</figure>
343				</div>
344				<div class="lightbox-image-container">
345					<figure data-wp-bind--class="state.currentImage.figureClassNames" data-wp-bind--style="state.figureStyles">
346						<img data-wp-bind--alt="state.currentImage.alt" data-wp-bind--class="state.currentImage.imgClassNames" data-wp-bind--style="state.imgStyles" data-wp-bind--src="state.enlargedSrc">
347					</figure>
348				</div>
349				<div class="scrim" style="background-color: $background_color" aria-hidden="true"></div>
350		</div>
351HTML;
352}
353
354/**
355 * Registers the `core/image` block on server.
356 *
357 * @since 5.9.0
358 */
359function register_block_core_image() {
360	register_block_type_from_metadata(
361		__DIR__ . '/image',
362		array(
363			'render_callback' => 'render_block_core_image',
364		)
365	);
366}
367add_action( 'init', 'register_block_core_image' );
368