1<?php
  2/**
  3 * Server-side rendering of the `core/template-part` block.
  4 *
  5 * @package WordPress
  6 */
  7
  8/**
  9 * Renders the `core/template-part` block on the server.
 10 *
 11 * @since 5.9.0
 12 *
 13 * @global WP_Embed $wp_embed WordPress Embed object.
 14 *
 15 * @param array $attributes The block attributes.
 16 *
 17 * @return string The render.
 18 */
 19function render_block_core_template_part( $attributes ) {
 20	static $seen_ids = array();
 21
 22	$template_part_id = null;
 23	$content          = null;
 24	$area             = WP_TEMPLATE_PART_AREA_UNCATEGORIZED;
 25	$theme            = isset( $attributes['theme'] ) ? $attributes['theme'] : get_stylesheet();
 26
 27	if ( isset( $attributes['slug'] ) && get_stylesheet() === $theme ) {
 28		$template_part_id    = $theme . '//' . $attributes['slug'];
 29		$template_part_query = new WP_Query(
 30			array(
 31				'post_type'           => 'wp_template_part',
 32				'post_status'         => 'publish',
 33				'post_name__in'       => array( $attributes['slug'] ),
 34				'tax_query'           => array(
 35					array(
 36						'taxonomy' => 'wp_theme',
 37						'field'    => 'name',
 38						'terms'    => $theme,
 39					),
 40				),
 41				'posts_per_page'      => 1,
 42				'no_found_rows'       => true,
 43				'lazy_load_term_meta' => false, // Do not lazy load term meta, as template parts only have one term.
 44			)
 45		);
 46		$template_part_post  = $template_part_query->have_posts() ? $template_part_query->next_post() : null;
 47		if ( $template_part_post ) {
 48			// A published post might already exist if this template part was customized elsewhere
 49			// or if it's part of a customized template.
 50			$block_template = _build_block_template_result_from_post( $template_part_post );
 51			$content        = $block_template->content;
 52			if ( isset( $block_template->area ) ) {
 53				$area = $block_template->area;
 54			}
 55			/**
 56			 * Fires when a block template part is loaded from a template post stored in the database.
 57			 *
 58			 * @since 5.9.0
 59			 *
 60			 * @param string  $template_part_id   The requested template part namespaced to the theme.
 61			 * @param array   $attributes         The block attributes.
 62			 * @param WP_Post $template_part_post The template part post object.
 63			 * @param string  $content            The template part content.
 64			 */
 65			do_action( 'render_block_core_template_part_post', $template_part_id, $attributes, $template_part_post, $content );
 66		} else {
 67			$template_part_file_path = '';
 68			// Else, if the template part was provided by the active theme,
 69			// render the corresponding file content.
 70			if ( 0 === validate_file( $attributes['slug'] ) ) {
 71				$block_template = get_block_file_template( $template_part_id, 'wp_template_part' );
 72
 73				if ( isset( $block_template->content ) ) {
 74					$content = $block_template->content;
 75				}
 76				if ( isset( $block_template->area ) ) {
 77					$area = $block_template->area;
 78				}
 79
 80				// Needed for the `render_block_core_template_part_file` and `render_block_core_template_part_none` actions below.
 81				$block_template_file = _get_block_template_file( 'wp_template_part', $attributes['slug'] );
 82				if ( $block_template_file ) {
 83					$template_part_file_path = $block_template_file['path'];
 84				}
 85			}
 86
 87			if ( '' !== $content && null !== $content ) {
 88				/**
 89				 * Fires when a block template part is loaded from a template part in the theme.
 90				 *
 91				 * @since 5.9.0
 92				 *
 93				 * @param string $template_part_id        The requested template part namespaced to the theme.
 94				 * @param array  $attributes              The block attributes.
 95				 * @param string $template_part_file_path Absolute path to the template path.
 96				 * @param string $content                 The template part content.
 97				 */
 98				do_action( 'render_block_core_template_part_file', $template_part_id, $attributes, $template_part_file_path, $content );
 99			} else {
100				/**
101				 * Fires when a requested block template part does not exist in the database nor in the theme.
102				 *
103				 * @since 5.9.0
104				 *
105				 * @param string $template_part_id        The requested template part namespaced to the theme.
106				 * @param array  $attributes              The block attributes.
107				 * @param string $template_part_file_path Absolute path to the not found template path.
108				 */
109				do_action( 'render_block_core_template_part_none', $template_part_id, $attributes, $template_part_file_path );
110			}
111		}
112	}
113
114	// WP_DEBUG_DISPLAY must only be honored when WP_DEBUG. This precedent
115	// is set in `wp_debug_mode()`.
116	$is_debug = WP_DEBUG && WP_DEBUG_DISPLAY;
117
118	if ( is_null( $content ) ) {
119		if ( $is_debug && isset( $attributes['slug'] ) ) {
120			return sprintf(
121				/* translators: %s: Template part slug. */
122				__( 'Template part has been deleted or is unavailable: %s' ),
123				$attributes['slug']
124			);
125		}
126
127		return '';
128	}
129
130	if ( isset( $seen_ids[ $template_part_id ] ) ) {
131		return $is_debug ?
132			// translators: Visible only in the front end, this warning takes the place of a faulty block.
133			__( '[block rendering halted]' ) :
134			'';
135	}
136
137	// Look up area definition.
138	$area_definition = null;
139	$defined_areas   = get_allowed_block_template_part_areas();
140	foreach ( $defined_areas as $defined_area ) {
141		if ( $defined_area['area'] === $area ) {
142			$area_definition = $defined_area;
143			break;
144		}
145	}
146
147	// If $area is not allowed, set it back to the uncategorized default.
148	if ( ! $area_definition ) {
149		$area = WP_TEMPLATE_PART_AREA_UNCATEGORIZED;
150	}
151
152	// Run through the actions that are typically taken on the_content.
153	$content                       = shortcode_unautop( $content );
154	$content                       = do_shortcode( $content );
155	$seen_ids[ $template_part_id ] = true;
156	$content                       = do_blocks( $content );
157	unset( $seen_ids[ $template_part_id ] );
158	$content = wptexturize( $content );
159	$content = convert_smilies( $content );
160	$content = wp_filter_content_tags( $content, "template_part_{$area}" );
161
162	// Handle embeds for block template parts.
163	global $wp_embed;
164	$content = $wp_embed->autoembed( $content );
165
166	if ( empty( $attributes['tagName'] ) || tag_escape( $attributes['tagName'] ) !== $attributes['tagName'] ) {
167		$area_tag = 'div';
168		if ( $area_definition && isset( $area_definition['area_tag'] ) ) {
169			$area_tag = $area_definition['area_tag'];
170		}
171		$html_tag = $area_tag;
172	} else {
173		$html_tag = esc_attr( $attributes['tagName'] );
174	}
175	$wrapper_attributes = get_block_wrapper_attributes();
176
177	return "<$html_tag $wrapper_attributes>" . str_replace( ']]>', ']]&gt;', $content ) . "</$html_tag>";
178}
179
180/**
181 * Returns an array of area variation objects for the template part block.
182 *
183 * @since 6.1.0
184 *
185 * @param array $instance_variations The variations for instances.
186 *
187 * @return array Array containing the block variation objects.
188 */
189function build_template_part_block_area_variations( $instance_variations ) {
190	$variations    = array();
191	$defined_areas = get_allowed_block_template_part_areas();
192
193	foreach ( $defined_areas as $area ) {
194		if ( 'uncategorized' !== $area['area'] ) {
195			$has_instance_for_area = false;
196			foreach ( $instance_variations as $variation ) {
197				if ( $variation['attributes']['area'] === $area['area'] ) {
198					$has_instance_for_area = true;
199					break;
200				}
201			}
202
203			$scope = $has_instance_for_area ? array() : array( 'inserter' );
204
205			$variations[] = array(
206				'name'        => 'area_' . $area['area'],
207				'title'       => $area['label'],
208				'description' => $area['description'],
209				'attributes'  => array(
210					'area' => $area['area'],
211				),
212				'scope'       => $scope,
213				'icon'        => $area['icon'],
214			);
215		}
216	}
217	return $variations;
218}
219
220/**
221 * Returns an array of instance variation objects for the template part block
222 *
223 * @since 6.1.0
224 *
225 * @return array Array containing the block variation objects.
226 */
227function build_template_part_block_instance_variations() {
228	// Block themes are unavailable during installation.
229	if ( wp_installing() ) {
230		return array();
231	}
232
233	if ( ! current_theme_supports( 'block-templates' ) && ! current_theme_supports( 'block-template-parts' ) ) {
234		return array();
235	}
236
237	$variations     = array();
238	$template_parts = get_block_templates(
239		array(
240			'post_type' => 'wp_template_part',
241		),
242		'wp_template_part'
243	);
244
245	$defined_areas = get_allowed_block_template_part_areas();
246	$icon_by_area  = array_combine( array_column( $defined_areas, 'area' ), array_column( $defined_areas, 'icon' ) );
247
248	foreach ( $template_parts as $template_part ) {
249		$variations[] = array(
250			'name'        => 'instance_' . sanitize_title( $template_part->slug ),
251			'title'       => $template_part->title,
252			// If there's no description for the template part don't show the
253			// block description. This is a bit hacky, but prevent the fallback
254			// by using a non-breaking space so that the value of description
255			// isn't falsey.
256			'description' => $template_part->description || '&nbsp;',
257			'attributes'  => array(
258				'slug'  => $template_part->slug,
259				'theme' => $template_part->theme,
260				'area'  => $template_part->area,
261			),
262			'scope'       => array( 'inserter' ),
263			'icon'        => isset( $icon_by_area[ $template_part->area ] ) ? $icon_by_area[ $template_part->area ] : null,
264			'example'     => array(
265				'attributes' => array(
266					'slug'  => $template_part->slug,
267					'theme' => $template_part->theme,
268					'area'  => $template_part->area,
269				),
270			),
271		);
272	}
273	return $variations;
274}
275
276/**
277 * Returns an array of all template part block variations.
278 *
279 * @since 5.9.0
280 *
281 * @return array Array containing the block variation objects.
282 */
283function build_template_part_block_variations() {
284	$instance_variations = build_template_part_block_instance_variations();
285	$area_variations     = build_template_part_block_area_variations( $instance_variations );
286	return array_merge( $area_variations, $instance_variations );
287}
288
289/**
290 * Registers the `core/template-part` block on the server.
291 *
292 * @since 5.9.0
293 */
294function register_block_core_template_part() {
295	register_block_type_from_metadata(
296		__DIR__ . '/template-part',
297		array(
298			'render_callback'    => 'render_block_core_template_part',
299			'variation_callback' => 'build_template_part_block_variations',
300		)
301	);
302}
303add_action( 'init', 'register_block_core_template_part' );
304