<?php
/**
* Server-side rendering of the `core/gallery` block.
*
* @package WordPress
*/
/**
* Handles backwards compatibility for Gallery Blocks,
* whose images feature a `data-id` attribute.
*
* Now that the Gallery Block contains inner Image Blocks,
* we add a custom `data-id` attribute before rendering the gallery
* so that the Image Block can pick it up in its render_callback.
*
* @param array $parsed_block The block being rendered.
* @return array The migrated block object.
*/
function block_core_gallery_data_id_backcompatibility( $parsed_block ) {
if ( 'core/gallery' === $parsed_block['blockName'] ) {
foreach ( $parsed_block['innerBlocks'] as $key => $inner_block ) {
if ( 'core/image' === $inner_block['blockName'] ) {
if ( ! isset( $parsed_block['innerBlocks'][ $key ]['attrs']['data-id'] ) && isset( $inner_block['attrs']['id'] ) ) {
$parsed_block['innerBlocks'][ $key ]['attrs']['data-id'] = esc_attr( $inner_block['attrs']['id'] );
}
}
}
}
return $parsed_block;
}
add_filter( 'render_block_data', 'block_core_gallery_data_id_backcompatibility' );
/**
* Adds a style tag for the --wp--style--unstable-gallery-gap var.
*
* The Gallery block needs to recalculate Image block width based on
* the current gap setting in order to maintain the number of flex columns
* so a css var is added to allow this.
*
* @param array $attributes Attributes of the block being rendered.
* @param string $content Content of the block being rendered.
* @return string The content of the block being rendered.
*/
function block_core_gallery_render( $attributes, $content ) {
$gap = _wp_array_get( $attributes, array( 'style', 'spacing', 'blockGap' ) );
// Skip if gap value contains unsupported characters.
// Regex for CSS value borrowed from `safecss_filter_attr`, and used here
// because we only want to match against the value, not the CSS attribute.
if ( is_array( $gap ) ) {
foreach ( $gap as $key => $value ) {
$gap[ $key ] = $value && preg_match( '%[\\\(&=}]|/\*%', $value ) ? null : $value;
}
} else {
$gap = $gap && preg_match( '%[\\\(&=}]|/\*%', $gap ) ? null : $gap;
}
$class = wp_unique_id( 'wp-block-gallery-' );
$content = preg_replace(
'/' . preg_quote( 'class="', '/' ) . '/',
'class="' . $class . ' ',
$content,
1
);
// --gallery-block--gutter-size is deprecated. --wp--style--gallery-gap-default should be used by themes that want to set a default
// gap on the gallery.
$fallback_gap = 'var( --wp--style--gallery-gap-default, var( --gallery-block--gutter-size, var( --wp--style--block-gap, 0.5em ) ) )';
$gap_value = $gap ? $gap : $fallback_gap;
$gap_column = $gap_value;
if ( is_array( $gap_value ) ) {
$gap_row = isset( $gap_value['top'] ) ? $gap_value['top'] : $fallback_gap;
$gap_column = isset( $gap_value['left'] ) ? $gap_value['left'] : $fallback_gap;
$gap_value = $gap_row === $gap_column ? $gap_row : $gap_row . ' ' . $gap_column;
}
// Set the CSS variable to the column value, and the `gap` property to the combined gap value.
$style = '.' . $class . '{ --wp--style--unstable-gallery-gap: ' . $gap_column . '; gap: ' . $gap_value . '}';
// Ideally styles should be loaded in the head, but blocks may be parsed
// after that, so loading in the footer for now.
// See https://core.trac.wordpress.org/ticket/53494.
add_action(
'wp_footer',
function () use ( $style ) {
echo '<style> ' . $style . '</style>';
}
);
return $content;
}
/**
* Registers the `core/gallery` block on server.
*/
function register_block_core_gallery() {
register_block_type_from_metadata(
__DIR__ . '/gallery',
array(
'render_callback' => 'block_core_gallery_render',
)
);
}
add_action( 'init', 'register_block_core_gallery' );