1<?php
  2/**
  3 * Position block support flag.
  4 *
  5 * @package WordPress
  6 * @since 6.2.0
  7 */
  8
  9/**
 10 * Registers the style block attribute for block types that support it.
 11 *
 12 * @since 6.2.0
 13 * @access private
 14 *
 15 * @param WP_Block_Type $block_type Block Type.
 16 */
 17function wp_register_position_support( $block_type ) {
 18	$has_position_support = block_has_support( $block_type, 'position', false );
 19
 20	// Set up attributes and styles within that if needed.
 21	if ( ! $block_type->attributes ) {
 22		$block_type->attributes = array();
 23	}
 24
 25	if ( $has_position_support && ! array_key_exists( 'style', $block_type->attributes ) ) {
 26		$block_type->attributes['style'] = array(
 27			'type' => 'object',
 28		);
 29	}
 30}
 31
 32/**
 33 * Renders position styles to the block wrapper.
 34 *
 35 * @since 6.2.0
 36 * @access private
 37 *
 38 * @param  string $block_content Rendered block content.
 39 * @param  array  $block         Block object.
 40 * @return string                Filtered block content.
 41 */
 42function wp_render_position_support( $block_content, $block ) {
 43	$block_type           = WP_Block_Type_Registry::get_instance()->get_registered( $block['blockName'] );
 44	$has_position_support = block_has_support( $block_type, 'position', false );
 45
 46	if (
 47		! $has_position_support ||
 48		empty( $block['attrs']['style']['position'] )
 49	) {
 50		return $block_content;
 51	}
 52
 53	$global_settings          = wp_get_global_settings();
 54	$theme_has_sticky_support = isset( $global_settings['position']['sticky'] ) ? $global_settings['position']['sticky'] : false;
 55	$theme_has_fixed_support  = isset( $global_settings['position']['fixed'] ) ? $global_settings['position']['fixed'] : false;
 56
 57	// Only allow output for position types that the theme supports.
 58	$allowed_position_types = array();
 59	if ( true === $theme_has_sticky_support ) {
 60		$allowed_position_types[] = 'sticky';
 61	}
 62	if ( true === $theme_has_fixed_support ) {
 63		$allowed_position_types[] = 'fixed';
 64	}
 65
 66	$style_attribute = isset( $block['attrs']['style'] ) ? $block['attrs']['style'] : null;
 67	$class_name      = wp_unique_id( 'wp-container-' );
 68	$selector        = ".$class_name";
 69	$position_styles = array();
 70	$position_type   = isset( $style_attribute['position']['type'] ) ? $style_attribute['position']['type'] : '';
 71	$wrapper_classes = array();
 72
 73	if (
 74		in_array( $position_type, $allowed_position_types, true )
 75	) {
 76		$wrapper_classes[] = $class_name;
 77		$wrapper_classes[] = 'is-position-' . $position_type;
 78		$sides             = array( 'top', 'right', 'bottom', 'left' );
 79
 80		foreach ( $sides as $side ) {
 81			$side_value = isset( $style_attribute['position'][ $side ] ) ? $style_attribute['position'][ $side ] : null;
 82			if ( null !== $side_value ) {
 83				/*
 84				 * For fixed or sticky top positions,
 85				 * ensure the value includes an offset for the logged in admin bar.
 86				 */
 87				if (
 88					'top' === $side &&
 89					( 'fixed' === $position_type || 'sticky' === $position_type )
 90				) {
 91					// Ensure 0 values can be used in `calc()` calculations.
 92					if ( '0' === $side_value || 0 === $side_value ) {
 93						$side_value = '0px';
 94					}
 95
 96					// Ensure current side value also factors in the height of the logged in admin bar.
 97					$side_value = "calc($side_value + var(--wp-admin--admin-bar--position-offset, 0px))";
 98				}
 99
100				$position_styles[] =
101					array(
102						'selector'     => $selector,
103						'declarations' => array(
104							$side => $side_value,
105						),
106					);
107			}
108		}
109
110		$position_styles[] =
111			array(
112				'selector'     => $selector,
113				'declarations' => array(
114					'position' => $position_type,
115					'z-index'  => '10',
116				),
117			);
118	}
119
120	if ( ! empty( $position_styles ) ) {
121		/*
122		 * Add to the style engine store to enqueue and render position styles.
123		 */
124		wp_style_engine_get_stylesheet_from_css_rules(
125			$position_styles,
126			array(
127				'context'  => 'block-supports',
128				'prettify' => false,
129			)
130		);
131
132		// Inject class name to block container markup.
133		$content = new WP_HTML_Tag_Processor( $block_content );
134		$content->next_tag();
135		foreach ( $wrapper_classes as $class ) {
136			$content->add_class( $class );
137		}
138		return (string) $content;
139	}
140
141	return $block_content;
142}
143
144// Register the block support.
145WP_Block_Supports::get_instance()->register(
146	'position',
147	array(
148		'register_attribute' => 'wp_register_position_support',
149	)
150);
151add_filter( 'render_block', 'wp_render_position_support', 10, 2 );
152