<?php
/**
 * HTML class.
 *
 * @since 2.6.7
 *
 * @package Soliloquy
 * @author SoliloquyWP Team <[email protected]>
 */

// Exit if accessed directly.
if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

if ( ! class_exists( 'Soliloquy_Html' ) ) {

	/**
	 * Soliloquy_Html class.
	 *
	 * @since 2.6.7
	 */
	class Soliloquy_Html {

		/**
		 * Holds the class object.
		 *
		 * @since 2.6.7
		 *
		 * @var object
		 */
		public static $instance;

		/**
		 * Holds the base class object.
		 *
		 * @since 2.6.7
		 *
		 * @var object
		 */
		public $base;

		/**
		 * Holds the word limit.
		 *
		 * @since 2.6.9
		 *
		 * @var int
		 */
		private $word_limit;

		/**
		 * Holds the word count.
		 *
		 * @since 2.6.9
		 *
		 * @var int
		 */
		private $word_count = 0;

		/**
		 * Primary class constructor.
		 *
		 * @since 2.6.7
		 */
		public function __construct() {

			// Load the base class object.
			$this->base = Soliloquy::get_instance();
		}

		/**
		 * Truncate HTML content.
		 *
		 * @since 2.6.9
		 *
		 * @param string $html      The HTML content to truncate.
		 * @param int    $word_limit The word limit.
		 * @param bool   $ellipses  Whether to add ellipses.
		 * @return string
		 */
		public function truncateHtml( $html, $word_limit, $ellipses = true ) {
			$this->word_limit = $word_limit;

			$dom = new DOMDocument();
			libxml_use_internal_errors( true );
			$dom->loadHTML( $html, LIBXML_HTML_NOIMPLIED | LIBXML_HTML_NODEFDTD );
			libxml_clear_errors();

			$this->trim_node( $dom, $ellipses );

			return $dom->saveHTML();
		}

		/**
		 * Truncate a node and its children to a word limit.
		 *
		 * @since 2.6.9
		 *
		 * @param DOMNode $node     The node to truncate.
		 * @param bool    $ellipses Whether to add ellipses.
		 */
		private function trim_node( $node, $ellipses ) {
			if ( $this->word_count >= $this->word_limit ) {
				// If the word limit has been reached, remove this node and all following siblings
				while ( $node ) {
					$nextNode = $node->nextSibling;
					if ( $node->parentNode ) {
						$node->parentNode->removeChild( $node );
					}
					$node = $nextNode;
				}
			} elseif ( $node instanceof DOMText ) {
				// If this is a text node, split it into words and count them
				$node_value = $node->nodeValue;
				// Count words in the original node value (including tags and blocks)
				$total_words      = preg_split( '/\s+/', $node_value );
				$total_word_count = count( $total_words );
				// Count words in the text content (excluding tags and blocks)
				$text_words = str_word_count( wp_strip_all_tags( preg_replace( '/<!--(.|\s)*?-->/', '', $node_value ) ) );
				// Subtract the words in the text content from the total words to get the words in the tags and blocks
				$tag_and_block_words = $total_word_count - $text_words;
				// Subtract the words in the tags and blocks from the word limit
				$this->word_limit += $tag_and_block_words;
				$words             = preg_split( '/\s+/', $node_value );
				$word_count        = count( $words );

				if ( $this->word_count + $word_count > $this->word_limit ) {
					// If this node contains too many words, trim it
					$words           = array_slice( $words, 0, $this->word_limit - $this->word_count );
					$node->nodeValue = implode( ' ', $words );
					if ( $ellipses ) {
						$node->nodeValue .= '...';
					}
					$this->word_count = $this->word_limit;
				} else {
					$this->word_count += $word_count;
				}
			} else {
				// If this is an element node, recursively trim its children
				$child = $node->firstChild;
				while ( $child ) {
					$next_child = $child->nextSibling;
					$this->trim_node( $child, $ellipses );
					$child = $next_child;
				}
			}
		}
	}
}