WordPress/wp-includes/blocks/image.php

368 lines
14 KiB
PHP

<?php
/**
* Server-side rendering of the `core/image` block.
*
* @package WordPress
*/
/**
* Renders the `core/image` block on the server,
* adding a data-id attribute to the element if core/gallery has added on pre-render.
*
* @param array $attributes The block attributes.
* @param string $content The block content.
* @param WP_Block $block The block object.
*
* @return string The block content with the data-id attribute added.
*/
function render_block_core_image( $attributes, $content, $block ) {
if ( false === stripos( $content, '<img' ) ) {
return '';
}
$processor = new WP_HTML_Tag_Processor( $content );
if ( ! $processor->next_tag( 'img' ) || null === $processor->get_attribute( 'src' ) ) {
return '';
}
if ( isset( $attributes['data-id'] ) ) {
// Add the data-id="$id" attribute to the img element
// to provide backwards compatibility for the Gallery Block,
// which now wraps Image Blocks within innerBlocks.
// The data-id attribute is added in a core/gallery `render_block_data` hook.
$processor->set_attribute( 'data-id', $attributes['data-id'] );
}
$link_destination = isset( $attributes['linkDestination'] ) ? $attributes['linkDestination'] : 'none';
$lightbox_settings = block_core_image_get_lightbox_settings( $block->parsed_block );
$view_js_file_handle = 'wp-block-image-view';
$script_handles = $block->block_type->view_script_handles;
/*
* If the lightbox is enabled and the image is not linked, add the filter
* and the JavaScript view file.
*/
if (
isset( $lightbox_settings ) &&
'none' === $link_destination &&
isset( $lightbox_settings['enabled'] ) &&
true === $lightbox_settings['enabled']
) {
$block->block_type->supports['interactivity'] = true;
if ( ! in_array( $view_js_file_handle, $script_handles, true ) ) {
$block->block_type->view_script_handles = array_merge( $script_handles, array( $view_js_file_handle ) );
}
/*
* This render needs to happen in a filter with priority 15 to ensure
* that it runs after the duotone filter and that duotone styles are
* applied to the image in the lightbox. We also need to ensure that the
* lightbox works with any plugins that might use filters as well. We
* can consider removing this in the future if the way the blocks are
* rendered changes, or if a new kind of filter is introduced.
*/
add_filter( 'render_block_core/image', 'block_core_image_render_lightbox', 15, 2 );
} else {
/*
* Remove the filter and the JavaScript view file if previously added by
* other Image blocks.
*/
remove_filter( 'render_block_core/image', 'block_core_image_render_lightbox', 15 );
// If the script is not needed, and it is still in the `view_script_handles`, remove it.
if ( in_array( $view_js_file_handle, $script_handles, true ) ) {
$block->block_type->view_script_handles = array_diff( $script_handles, array( $view_js_file_handle ) );
}
}
return $processor->get_updated_html();
}
/**
* Adds the lightboxEnabled flag to the block data.
*
* This is used to determine whether the lightbox should be rendered or not.
*
* @param array $block Block data.
*
* @return array Filtered block data.
*/
function block_core_image_get_lightbox_settings( $block ) {
// Get the lightbox setting from the block attributes.
if ( isset( $block['attrs']['lightbox'] ) ) {
$lightbox_settings = $block['attrs']['lightbox'];
// If the lightbox setting is not set in the block attributes,
// check the legacy lightbox settings that are set using the
// `gutenberg_should_render_lightbox` filter.
// We can remove this elseif statement when the legacy lightbox settings are removed.
} elseif ( isset( $block['legacyLightboxSettings'] ) ) {
$lightbox_settings = $block['legacyLightboxSettings'];
}
if ( ! isset( $lightbox_settings ) ) {
$lightbox_settings = wp_get_global_settings( array( 'lightbox' ), array( 'block_name' => 'core/image' ) );
// If not present in global settings, check the top-level global settings.
//
// NOTE: If no block-level settings are found, the previous call to
// `wp_get_global_settings` will return the whole `theme.json`
// structure in which case we can check if the "lightbox" key is present at
// the top-level of the global settings and use its value.
if ( isset( $lightbox_settings['lightbox'] ) ) {
$lightbox_settings = wp_get_global_settings( array( 'lightbox' ) );
}
}
return $lightbox_settings ?? null;
}
/**
* Adds the directives and layout needed for the lightbox behavior.
*
* @param string $block_content Rendered block content.
* @param array $block Block object.
*
* @return string Filtered block content.
*/
function block_core_image_render_lightbox( $block_content, $block ) {
/*
* If it's not possible that an IMG element exists then return the given
* block content as-is. It may be that there's no actual image in the block
* or it could be that another plugin already modified this HTML.
*/
if ( false === stripos( $block_content, '<img' ) ) {
return $block_content;
}
$processor = new WP_HTML_Tag_Processor( $block_content );
$aria_label = __( 'Enlarge image' );
/*
* If there's definitely no IMG element in the block then return the given
* block content as-is. There's nothing that this code can knowingly modify
* to add the lightbox behavior.
*/
if ( ! $processor->next_tag( 'img' ) ) {
return $block_content;
}
$alt_attribute = $processor->get_attribute( 'alt' );
// An empty alt attribute `alt=""` is valid for decorative images.
if ( is_string( $alt_attribute ) ) {
$alt_attribute = trim( $alt_attribute );
}
// It only makes sense to append the alt text to the button aria-label when the alt text is non-empty.
if ( $alt_attribute ) {
/* translators: %s: Image alt text. */
$aria_label = sprintf( __( 'Enlarge image: %s' ), $alt_attribute );
}
// Currently, we are only enabling the zoom animation.
$lightbox_animation = 'zoom';
// Note: We want to store the `src` in the context so we
// can set it dynamically when the lightbox is opened.
if ( isset( $block['attrs']['id'] ) ) {
$img_uploaded_src = wp_get_attachment_url( $block['attrs']['id'] );
$img_metadata = wp_get_attachment_metadata( $block['attrs']['id'] );
$img_width = $img_metadata['width'] ?? 'none';
$img_height = $img_metadata['height'] ?? 'none';
} else {
$img_uploaded_src = $processor->get_attribute( 'src' );
$img_width = 'none';
$img_height = 'none';
}
if ( isset( $block['attrs']['scale'] ) ) {
$scale_attr = $block['attrs']['scale'];
} else {
$scale_attr = false;
}
$w = new WP_HTML_Tag_Processor( $block_content );
$w->next_tag( 'figure' );
$w->add_class( 'wp-lightbox-container' );
$w->set_attribute( 'data-wp-interactive', true );
$w->set_attribute(
'data-wp-context',
sprintf(
'{ "core":
{ "image":
{ "imageLoaded": false,
"initialized": false,
"lightboxEnabled": false,
"hideAnimationEnabled": false,
"preloadInitialized": false,
"lightboxAnimation": "%s",
"imageUploadedSrc": "%s",
"imageCurrentSrc": "",
"targetWidth": "%s",
"targetHeight": "%s",
"scaleAttr": "%s",
"dialogLabel": "%s"
}
}
}',
$lightbox_animation,
$img_uploaded_src,
$img_width,
$img_height,
$scale_attr,
__( 'Enlarged image' )
)
);
$w->next_tag( 'img' );
$w->set_attribute( 'data-wp-init', 'effects.core.image.initOriginImage' );
$w->set_attribute( 'data-wp-on--load', 'actions.core.image.handleLoad' );
$w->set_attribute( 'data-wp-effect', 'effects.core.image.setButtonStyles' );
// We need to set an event callback on the `img` specifically
// because the `figure` element can also contain a caption, and
// we don't want to trigger the lightbox when the caption is clicked.
$w->set_attribute( 'data-wp-on--click', 'actions.core.image.showLightbox' );
$w->set_attribute( 'data-wp-effect--setStylesOnResize', 'effects.core.image.setStylesOnResize' );
$body_content = $w->get_updated_html();
// Add a button alongside image in the body content.
$img = null;
preg_match( '/<img[^>]+>/', $body_content, $img );
$button =
$img[0]
. '<button
class="lightbox-trigger"
type="button"
aria-haspopup="dialog"
aria-label="' . esc_attr( $aria_label ) . '"
data-wp-on--click="actions.core.image.showLightbox"
data-wp-style--right="context.core.image.imageButtonRight"
data-wp-style--top="context.core.image.imageButtonTop"
style="background: #000"
>
<svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" aria-hidden="true" focusable="false">
<Path stroke="#FFFFFF" d="M6 4a2 2 0 0 0-2 2v3h1.5V6a.5.5 0 0 1 .5-.5h3V4H6Zm3 14.5H6a.5.5 0 0 1-.5-.5v-3H4v3a2 2 0 0 0 2 2h3v-1.5Zm6 1.5v-1.5h3a.5.5 0 0 0 .5-.5v-3H20v3a2 2 0 0 1-2 2h-3Zm3-16a2 2 0 0 1 2 2v3h-1.5V6a.5.5 0 0 0-.5-.5h-3V4h3Z" />
</svg>
</button>';
$body_content = preg_replace( '/<img[^>]+>/', $button, $body_content );
// We need both a responsive image and an enlarged image to animate
// the zoom seamlessly on slow internet connections; the responsive
// image is a copy of the one in the body, which animates immediately
// as the lightbox is opened, while the enlarged one is a full-sized
// version that will likely still be loading as the animation begins.
$m = new WP_HTML_Tag_Processor( $block_content );
$m->next_tag( 'figure' );
$m->add_class( 'responsive-image' );
$m->next_tag( 'img' );
// We want to set the 'src' attribute to an empty string in the responsive image
// because otherwise, as of this writing, the wp_filter_content_tags() function in
// WordPress will automatically add a 'srcset' attribute to the image, which will at
// times cause the incorrectly sized image to be loaded in the lightbox on Firefox.
// Because of this, we bind the 'src' attribute explicitly the current src to reliably
// use the exact same image as in the content when the lightbox is first opened while
// we wait for the larger image to load.
$m->set_attribute( 'src', '' );
$m->set_attribute( 'data-wp-bind--src', 'context.core.image.imageCurrentSrc' );
$m->set_attribute( 'data-wp-style--object-fit', 'selectors.core.image.lightboxObjectFit' );
$initial_image_content = $m->get_updated_html();
$q = new WP_HTML_Tag_Processor( $block_content );
$q->next_tag( 'figure' );
$q->add_class( 'enlarged-image' );
$q->next_tag( 'img' );
// We set the 'src' attribute to an empty string to prevent the browser from loading the image
// on initial page load, then bind the attribute to a selector that returns the full-sized image src when
// the lightbox is opened. We could use 'loading=lazy' in combination with the 'hidden' attribute to
// accomplish the same behavior, but that approach breaks progressive loading of the image in Safari
// and Chrome (see https://github.com/WordPress/gutenberg/pull/52765#issuecomment-1674008151). Until that
// is resolved, manually setting the 'src' seems to be the best solution to load the large image on demand.
$q->set_attribute( 'src', '' );
$q->set_attribute( 'data-wp-bind--src', 'selectors.core.image.enlargedImgSrc' );
$q->set_attribute( 'data-wp-style--object-fit', 'selectors.core.image.lightboxObjectFit' );
$enlarged_image_content = $q->get_updated_html();
// If the current theme does NOT have a `theme.json`, or the colors are not defined,
// we need to set the background color & close button color to some default values
// because we can't get them from the Global Styles.
$background_color = '#fff';
$close_button_color = '#000';
if ( wp_theme_has_theme_json() ) {
$global_styles_color = wp_get_global_styles( array( 'color' ) );
if ( ! empty( $global_styles_color['background'] ) ) {
$background_color = esc_attr( $global_styles_color['background'] );
}
if ( ! empty( $global_styles_color['text'] ) ) {
$close_button_color = esc_attr( $global_styles_color['text'] );
}
}
$close_button_icon = '<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" width="15" height="15" aria-hidden="true" focusable="false"><path d="M13 11.8l6.1-6.3-1-1-6.1 6.2-6.1-6.2-1 1 6.1 6.3-6.5 6.7 1 1 6.5-6.6 6.5 6.6 1-1z"></path></svg>';
$close_button_label = esc_attr__( 'Close' );
$lightbox_html = <<<HTML
<div data-wp-body="" class="wp-lightbox-overlay $lightbox_animation"
data-wp-bind--role="selectors.core.image.roleAttribute"
data-wp-bind--aria-label="selectors.core.image.dialogLabel"
data-wp-class--initialized="context.core.image.initialized"
data-wp-class--active="context.core.image.lightboxEnabled"
data-wp-class--hideAnimationEnabled="context.core.image.hideAnimationEnabled"
data-wp-bind--aria-modal="selectors.core.image.ariaModal"
data-wp-effect="effects.core.image.initLightbox"
data-wp-on--keydown="actions.core.image.handleKeydown"
data-wp-on--touchstart="actions.core.image.handleTouchStart"
data-wp-on--touchmove="actions.core.image.handleTouchMove"
data-wp-on--touchend="actions.core.image.handleTouchEnd"
data-wp-on--click="actions.core.image.hideLightbox"
tabindex="-1"
>
<button type="button" aria-label="$close_button_label" style="fill: $close_button_color" class="close-button" data-wp-on--click="actions.core.image.hideLightbox">
$close_button_icon
</button>
<div class="lightbox-image-container">$initial_image_content</div>
<div class="lightbox-image-container">$enlarged_image_content</div>
<div class="scrim" style="background-color: $background_color" aria-hidden="true"></div>
</div>
HTML;
return str_replace( '</figure>', $lightbox_html . '</figure>', $body_content );
}
/**
* Ensures that the view script has the `wp-interactivity` dependency.
*
* @since 6.4.0
*
* @global WP_Scripts $wp_scripts
*/
function block_core_image_ensure_interactivity_dependency() {
global $wp_scripts;
if (
isset( $wp_scripts->registered['wp-block-image-view'] ) &&
! in_array( 'wp-interactivity', $wp_scripts->registered['wp-block-image-view']->deps, true )
) {
$wp_scripts->registered['wp-block-image-view']->deps[] = 'wp-interactivity';
}
}
add_action( 'wp_print_scripts', 'block_core_image_ensure_interactivity_dependency' );
/**
* Registers the `core/image` block on server.
*/
function register_block_core_image() {
register_block_type_from_metadata(
__DIR__ . '/image',
array(
'render_callback' => 'render_block_core_image',
)
);
}
add_action( 'init', 'register_block_core_image' );