<?php
/**
* Elements styles block support.
*
* @package WordPress
* @since 5.8.0
*/
/**
* Get the elements class names.
*
* @since 6.0.0
* @access private
*
* @param array $block Block object.
* @return string The unique class name.
*/
function wp_get_elements_class_name( $block ) {
return 'wp-elements-' . md5( serialize( $block ) );
}
/**
* Update the block content with elements class names.
*
* @since 5.8.0
* @access private
*
* @param string $block_content Rendered block content.
* @param array $block Block object.
* @return string Filtered block content.
*/
function wp_render_elements_support( $block_content, $block ) {
if ( ! $block_content ) {
return $block_content;
}
$block_type = WP_Block_Type_Registry::get_instance()->get_registered( $block['blockName'] );
$skip_link_color_serialization = wp_should_skip_block_supports_serialization( $block_type, 'color', 'link' );
if ( $skip_link_color_serialization ) {
return $block_content;
}
$link_color = null;
if ( ! empty( $block['attrs'] ) ) {
$link_color = _wp_array_get( $block['attrs'], array( 'style', 'elements', 'link', 'color', 'text' ), null );
}
/*
* For now we only care about link color.
* This code in the future when we have a public API
* should take advantage of WP_Theme_JSON::compute_style_properties
* and work for any element and style.
*/
if ( null === $link_color ) {
return $block_content;
}
$class_name = wp_get_elements_class_name( $block );
// Like the layout hook this assumes the hook only applies to blocks with a single wrapper.
// Retrieve the opening tag of the first HTML element.
$html_element_matches = array();
preg_match( '/<[^>]+>/', $block_content, $html_element_matches, PREG_OFFSET_CAPTURE );
$first_element = $html_element_matches[0][0];
// If the first HTML element has a class attribute just add the new class
// as we do on layout and duotone.
if ( strpos( $first_element, 'class="' ) !== false ) {
$content = preg_replace(
'/' . preg_quote( 'class="', '/' ) . '/',
'class="' . $class_name . ' ',
$block_content,
1
);
} else {
// If the first HTML element has no class attribute we should inject the attribute before the attribute at the end.
$first_element_offset = $html_element_matches[0][1];
$content = substr_replace( $block_content, ' class="' . $class_name . '"', $first_element_offset + strlen( $first_element ) - 1, 0 );
}
return $content;
}
/**
* Render the elements stylesheet.
*
* In the case of nested blocks we want the parent element styles to be rendered before their descendants.
* This solves the issue of an element (e.g.: link color) being styled in both the parent and a descendant:
* we want the descendant style to take priority, and this is done by loading it after, in DOM order.
*
* @since 6.0.0
* @access private
*
* @param string|null $pre_render The pre-rendered content. Default null.
* @param array $block The block being rendered.
*
* @return null
*/
function wp_render_elements_support_styles( $pre_render, $block ) {
$block_type = WP_Block_Type_Registry::get_instance()->get_registered( $block['blockName'] );
$skip_link_color_serialization = wp_should_skip_block_supports_serialization( $block_type, 'color', 'link' );
if ( $skip_link_color_serialization ) {
return null;
}
$link_color = null;
if ( ! empty( $block['attrs'] ) ) {
$link_color = _wp_array_get( $block['attrs'], array( 'style', 'elements', 'link', 'color', 'text' ), null );
}
/*
* For now we only care about link color.
* This code in the future when we have a public API
* should take advantage of WP_Theme_JSON::compute_style_properties
* and work for any element and style.
*/
if ( null === $link_color ) {
return null;
}
$class_name = wp_get_elements_class_name( $block );
if ( strpos( $link_color, 'var:preset|color|' ) !== false ) {
// Get the name from the string and add proper styles.
$index_to_splice = strrpos( $link_color, '|' ) + 1;
$link_color_name = substr( $link_color, $index_to_splice );
$link_color = "var(--wp--preset--color--$link_color_name)";
}
$link_color_declaration = esc_html( safecss_filter_attr( "color: $link_color" ) );
$style = ".$class_name a{" . $link_color_declaration . ';}';
wp_enqueue_block_support_styles( $style );
return null;
}
add_filter( 'render_block', 'wp_render_elements_support', 10, 2 );
add_filter( 'pre_render_block', 'wp_render_elements_support_styles', 10, 2 );