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<?php/**
 * Shadow block support flag.
 *
 * @package WordPress
 * @since 6.3.0
 */
 
 /**
 * Registers the style and shadow block attributes for block types that support it.
 *
 * @since 6.3.0
 * @access private
 *
 * @param WP_Block_Type $block_type Block Type.
 */
 function wp_register_shadow_support( $block_type ) {
 $has_shadow_support = block_has_support( $block_type, 'shadow', false );
 
 if ( ! $has_shadow_support ) {
 return;
 }
 
 if ( ! $block_type->attributes ) {
 $block_type->attributes = array();
 }
 
 if ( array_key_exists( 'style', $block_type->attributes ) ) {
 $block_type->attributes['style'] = array(
 'type' => 'object',
 );
 }
 
 if ( array_key_exists( 'shadow', $block_type->attributes ) ) {
 $block_type->attributes['shadow'] = array(
 'type' => 'string',
 );
 }
 }
 
 /**
 * Add CSS classes and inline styles for shadow features to the incoming attributes array.
 * This will be applied to the block markup in the front-end.
 *
 * @since 6.3.0
 * @since 6.6.0 Return early if __experimentalSkipSerialization is true.
 * @access private
 *
 * @param  WP_Block_Type $block_type       Block type.
 * @param  array         $block_attributes Block attributes.
 * @return array Shadow CSS classes and inline styles.
 */
 function wp_apply_shadow_support( $block_type, $block_attributes ) {
 $has_shadow_support = block_has_support( $block_type, 'shadow', false );
 
 if (
 ! $has_shadow_support ||
 wp_should_skip_block_supports_serialization( $block_type, 'shadow' )
 ) {
 return array();
 }
 
 $shadow_block_styles = array();
 
 $custom_shadow                 = $block_attributes['style']['shadow'] ?? null;
 $shadow_block_styles['shadow'] = $custom_shadow;
 
 $attributes = array();
 $styles     = wp_style_engine_get_styles( $shadow_block_styles );
 
 if ( ! empty( $styles['css'] ) ) {
 $attributes['style'] = $styles['css'];
 }
 
 return $attributes;
 }
 
 // Register the block support.
 WP_Block_Supports::get_instance()->register(
 'shadow',
 array(
 'register_attribute' => 'wp_register_shadow_support',
 'apply'              => 'wp_apply_shadow_support',
 )
 );
 
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