he = false;

			$content = $this->run_shortcode( $post->post_content );
			$this->autoembed( $content );

			$this->usecache = true;
		}
	}

	/**
	 * Passes any unlinked URLs that are on their own line to WP_Embed::shortcode() for potential embedding.
	 *
	 * @see WP_Embed::autoembed_callback()
	 *
	 * @param string $content The content to be searched.
	 * @return string Potentially modified $content.
	 */
	public function autoembed( $content ) {
		// Replace line breaks from all HTML elements with placeholders.
		$content = wp_replace_in_html_tags( $content, array( "\n" => '<!-- wp-line-break -->' ) );

		if ( preg_match( '#(^|\s|>)https?://#i', $content ) ) {
			// Find URLs on their own line.
			$content = preg_replace_callback( '|^(\s*)(https?://[^\s<>"]+)(\s*)$|im', array( $this, 'autoembed_callback' ), $content );
			// Find URLs in their own paragraph.
			$content = preg_replace_callback( '|(<p(?: [^>]*)?>\s*)(https?://[^\s<>"]+)(\s*<\/p>)|i', array( $this, 'autoembed_callback' ), $content );
		}

		// Put the line breaks back.
		return str_replace( '<!-- wp-line-break -->', "\n", $content );
	}

	/**
	 * Callback function for WP_Embed::autoembed().
	 *
	 * @param array $match A regex match array.
	 * @return string The embed HTML on success, otherwise the original URL.
	 */
	public function autoembed_callback( $match ) {
		$oldval              = $this->linkifunknown;
		$this->linkifunknown = false;
		$return              = $this->shortcode( array(), $match[2] );
		$this->linkifunknown = $oldval;

		return $match[1] . $return . $match[3];
	}

	/**
	 * Conditionally makes a hyperlink based on an internal class variable.
	 *
	 * @param string $url URL to potentially be linked.
	 * @return string|false Linked URL or the original URL. False if 'return_false_on_fail' is true.
	 */
	public function maybe_make_link( $url ) {
		if ( $this->return_false_on_fail ) {
			return false;
		}

		$output = ( $this->linkifunknown ) ? '<a href="' . esc_url( $url ) . '">' . esc_html( $url ) . '</a>' : $url;

		/**
		 * Filters the returned, maybe-linked embed URL.
		 *
		 * @since 2.9.0
		 *
		 * @param string $output The linked or original URL.
		 * @param string $url    The original URL.
		 */
		return apply_filters( 'embed_maybe_make_link', $output, $url );
	}

	/**
	 * Find the oEmbed cache post ID for a given cache key.
	 *
	 * @since 4.9.0
	 *
	 * @param string $cache_key oEmbed cache key.
	 * @return int|null Post ID on success, null on failure.
	 */
	public function find_oembed_post_id( $cache_key ) {
		$cache_group    = 'oembed_cache_post';
		$oembed_post_id = wp_cache_get( $cache_key, $cache_group );

		if ( $oembed_post_id && 'oembed_cache' === get_post_type( $oembed_post_id ) ) {
			return $oembed_post_id;
		}

		$oembed_post_query = new WP_Query(
			array(
				'post_type'              => 'oembed_cache',
				'post_status'            => 'publish',
				'name'                   => $cache_key,
				'posts_per_page'         => 1,
				'no_found_rows'          => true,
				'cache_results'          => true,
				'update_post_meta_cache' => false,
				'update_post_term_cache' => false,
				'lazy_load_term_meta'    => false,
			)
		);

		if ( ! empty( $oembed_post_query->posts ) ) {
			// Note: 'fields' => 'ids' is not being used in order to cache the post object as it will be needed.
			$oembed_post_id = $oembed_post_query->posts[0]->ID;
			wp_cache_set( $cache_key, $oembed_post_id, $cache_group );

			return $oembed_post_id;
		}

		return null;
	}
}