<?php

/**

 * Interactivity API: WP_Interactivity_API_Directives_Processor class.

 *

 * @package WordPress

 * @subpackage Interactivity API

 * @since 6.5.0

 */

/**

 * Class used to iterate over the tags of an HTML string and help process the

 * directive attributes.

 *

 * @since 6.5.0

 *

 * @access private

 */

final class WP_Interactivity_API_Directives_Processor extends WP_HTML_Tag_Processor {

	/**

	 * List of tags whose closer tag is not visited by the WP_HTML_Tag_Processor.

	 *

	 * @since 6.5.0

	 * @var string[]

	 */

	const TAGS_THAT_DONT_VISIT_CLOSER_TAG = array(

		'SCRIPT',

		'IFRAME',

		'NOEMBED',

		'NOFRAMES',

		'STYLE',

		'TEXTAREA',

		'TITLE',

		'XMP',

	);

	/**

	 * Returns the content between two balanced template tags.

	 *

	 * It positions the cursor in the closer tag of the balanced template tag,

	 * if it exists.

	 *

	 * @since 6.5.0

	 *

	 * @access private

	 *

	 * @return string|null The content between the current opener template tag and its matching closer tag or null if it

	 *                     doesn't find the matching closing tag or the current tag is not a template opener tag.

	 */

	public function get_content_between_balanced_template_tags() {

		if ( 'TEMPLATE' !== $this->get_tag() ) {

			return null;

		}

		$positions = $this->get_after_opener_tag_and_before_closer_tag_positions();

		if ( ! $positions ) {

			return null;

		}

		list( $after_opener_tag, $before_closer_tag ) = $positions;

		return substr( $this->html, $after_opener_tag, $before_closer_tag - $after_opener_tag );

	}

	/**

	 * Sets the content between two balanced tags.

	 *

	 * @since 6.5.0

	 *

	 * @access private

	 *

	 * @param string $new_content The string to replace the content between the matching tags.

	 * @return bool Whether the content was successfully replaced.

	 */

	public function set_content_between_balanced_tags( string $new_content ): bool {

		$positions = $this->get_after_opener_tag_and_before_closer_tag_positions( true );

		if ( ! $positions ) {

			return false;

		}

		list( $after_opener_tag, $before_closer_tag ) = $positions;

		$this->lexical_updates[] = new WP_HTML_Text_Replacement(

			$after_opener_tag,

			$before_closer_tag - $after_opener_tag,

			esc_html( $new_content )

		);

		return true;

	}

	/**

	 * Appends content after the closing tag of a template tag.

	 *

	 * It positions the cursor in the closer tag of the balanced template tag,

	 * if it exists.

	 *

	 * @access private

	 *

	 * @param string $new_content The string to append after the closing template tag.

	 * @return bool Whether the content was successfully appended.

	 */

	public function append_content_after_template_tag_closer( string $new_content ): bool {

		if ( empty( $new_content ) || 'TEMPLATE' !== $this->get_tag() || ! $this->is_tag_closer() ) {

			return false;

		}

		// Flushes any changes.

		$this->get_updated_html();

		$bookmark = 'append_content_after_template_tag_closer';

		$this->set_bookmark( $bookmark );

		$after_closing_tag = $this->bookmarks[ $bookmark ]->start + $this->bookmarks[ $bookmark ]->length;

		$this->release_bookmark( $bookmark );

		// Appends the new content.

		$this->lexical_updates[] = new WP_HTML_Text_Replacement( $after_closing_tag, 0, $new_content );

		return true;

	}

	/**

	 * Gets the positions right after the opener tag and right before the closer

	 * tag in a balanced tag.

	 *

	 * By default, it positions the cursor in the closer tag of the balanced tag.

	 * If $rewind is true, it seeks back to the opener tag.

	 *

	 * @since 6.5.0

	 *

	 * @access private

	 *

	 * @param bool $rewind Optional. Whether to seek back to the opener tag after finding the positions. Defaults to false.

	 * @return array|null Start and end byte position, or null when no balanced tag bookmarks.

	 */

	private function get_after_opener_tag_and_before_closer_tag_positions( bool $rewind = false ) {

		// Flushes any changes.

		$this->get_updated_html();

		$bookmarks = $this->get_balanced_tag_bookmarks();

		if ( ! $bookmarks ) {

			return null;

		}

		list( $opener_tag, $closer_tag ) = $bookmarks;

		$after_opener_tag  = $this->bookmarks[ $opener_tag ]->start + $this->bookmarks[ $opener_tag ]->length;

		$before_closer_tag = $this->bookmarks[ $closer_tag ]->start;

		if ( $rewind ) {

			$this->seek( $opener_tag );

		}

		$this->release_bookmark( $opener_tag );

		$this->release_bookmark( $closer_tag );

		return array( $after_opener_tag, $before_closer_tag );

	}

	/**

	 * Returns a pair of bookmarks for the current opener tag and the matching

	 * closer tag.

	 *

	 * It positions the cursor in the closer tag of the balanced tag, if it

	 * exists.

	 *

	 * @since 6.5.0

	 *

	 * @return array|null A pair of bookmarks, or null if there's no matching closing tag.

	 */

	private function get_balanced_tag_bookmarks() {

		static $i   = 0;

		$opener_tag = 'opener_tag_of_balanced_tag_' . ++$i;

		$this->set_bookmark( $opener_tag );

		if ( ! $this->next_balanced_tag_closer_tag() ) {

			$this->release_bookmark( $opener_tag );

			return null;

		}

		$closer_tag = 'closer_tag_of_balanced_tag_' . ++$i;

		$this->set_bookmark( $closer_tag );

		return array( $opener_tag, $closer_tag );

	}

	/**

	 * Skips processing the content between tags.

	 *

	 * It positions the cursor in the closer tag of the foreign element, if it

	 * exists.

	 *

	 * This function is intended to skip processing SVG and MathML inner content

	 * instead of bailing out the whole processing.

	 *

	 * @since 6.5.0

	 *

	 * @access private

	 *

	 * @return bool Whether the foreign content was successfully skipped.

	 */

	public function skip_to_tag_closer(): bool {

		$depth    = 1;

		$tag_name = $this->get_tag();

		while ( $depth > 0 && $this->next_tag( array( 'tag_closers' => 'visit' ) ) ) {

			if ( ! $this->is_tag_closer() && $this->get_attribute_names_with_prefix( 'data-wp-' ) ) {

				/* translators: 1: SVG or MATH HTML tag. */

				$message = sprintf( __( 'Interactivity directives were detected inside an incompatible %1$s tag. These directives will be ignored in the server side render.' ), $tag_name );

				_doing_it_wrong( __METHOD__, $message, '6.6.0' );

			}

			if ( $this->get_tag() === $tag_name ) {

				if ( $this->has_self_closing_flag() ) {

					continue;

				}

				$depth += $this->is_tag_closer() ? -1 : 1;

			}

		}

		return 0 === $depth;

	}

	/**

	 * Finds the matching closing tag for an opening tag.

	 *

	 * When called while the processor is on an open tag, it traverses the HTML

	 * until it finds the matching closer tag, respecting any in-between content,

	 * including nested tags of the same name. Returns false when called on a

	 * closer tag, a tag that doesn't have a closer tag (void), a tag that

	 * doesn't visit the closer tag, or if no matching closing tag was found.

	 *

	 * @since 6.5.0

	 *

	 * @access private

	 *

	 * @return bool Whether a matching closing tag was found.

	 */

	public function next_balanced_tag_closer_tag(): bool {

		$depth    = 0;

		$tag_name = $this->get_tag();

		if ( ! $this->has_and_visits_its_closer_tag() ) {

			return false;

		}

		while ( $this->next_tag(

			array(

				'tag_name'    => $tag_name,

				'tag_closers' => 'visit',

			)

		) ) {

			if ( ! $this->is_tag_closer() ) {

				++$depth;

				continue;

			}

			if ( 0 === $depth ) {

				return true;

			}

			--$depth;

		}

		return false;

	}

	/**

	 * Checks whether the current tag has and will visit its matching closer tag.

	 *

	 * @since 6.5.0

	 *

	 * @access private

	 *

	 * @return bool Whether the current tag has a closer tag.

	 */

	public function has_and_visits_its_closer_tag(): bool {

		$tag_name = $this->get_tag();

		return null !== $tag_name && (

			! WP_HTML_Processor::is_void( $tag_name ) &&

			! in_array( $tag_name, self::TAGS_THAT_DONT_VISIT_CLOSER_TAG, true )

		);

	}

}