<?php
/**
 * The ESI class.
 *
 * This is used to define all esi related functions.
 *
 * @since      	1.1.3
 * @package    	LiteSpeed
 * @subpackage 	LiteSpeed/src
 * @author     	LiteSpeed Technologies <info@litespeedtech.com>
 */
namespace LiteSpeed;

defined( 'WPINC' ) || exit;

class ESI extends Instance {
	protected static $_instance;

	private static $has_esi = false;
	private static $_combine_ids = array();
	private $esi_args = null;
	private $_esi_preserve_list = array();
	private $_nonce_actions = array( -1 => '' ); // val is cache control

	const QS_ACTION = 'lsesi';
	const QS_PARAMS = 'esi';
	const COMBO = '__combo'; // ESI include combine='main' handler

	const PARAM_ARGS = 'args';
	const PARAM_ID = 'id';
	const PARAM_INSTANCE = 'instance';
	const PARAM_NAME = 'name';

	const WIDGET_O_ESIENABLE = 'widget_esi_enable';
	const WIDGET_O_TTL = 'widget_ttl';

	/**
	 * Confructor of ESI
	 *
	 * @since    1.2.0
	 * @access protected
	 */
	protected function __construct() {
		/**
		 * Bypass ESI related funcs if disabled ESI to fix potential DIVI compatibility issue
		 * @since  2.9.7.2
		 */
		if ( Router::is_ajax() || ! Router::esi_enabled() ) {
			return;
		}

		// Init ESI in `after_setup_theme` hook after detected if LITESPEED_DISABLE_ALL is ON or not
		add_action( 'litespeed_initing', array( $this, 'esi_init' ) );

		/**
		 * Overwrite wp_create_nonce func
		 * @since  2.9.5
		 */
		if ( ! is_admin() && ! function_exists( 'wp_create_nonce' ) ) {
			$this->_transform_nonce();
		}
	}

	/**
	 * Init ESI related hooks
	 *
	 * Load delayed by hook to give the ability to bypass by LITESPEED_DISABLE_ALL const
	 *
	 * @since 2.9.7.2
	 * @access public
	 */
	public function esi_init() {
		add_action( 'template_include', array( $this, 'esi_template' ), 99999 );

		add_action( 'load-widgets.php', __NAMESPACE__ . '\Purge::purge_widget' );
		add_action( 'wp_update_comment_count', __NAMESPACE__ . '\Purge::purge_comment_widget' );

		/**
		 * Recover REQUEST_URI
		 * @since  1.8.1
		 */
		if ( ! empty( $_GET[ self::QS_ACTION ] ) ) {
			$this->_register_esi_actions();
		}

		/**
		 * Shortcode ESI
		 *
		 * To use it, just change the origianl shortcode as below:
		 * 		old: [someshortcode aa='bb']
		 * 		new: [esi someshortcode aa='bb' cache='private,no-vary' ttl='600']
		 *
		 * 	1. `cache` attribute is optional, default to 'public,no-vary'.
		 * 	2. `ttl` attribute is optional, default is your public TTL setting.
		 *
		 * @since  2.8
		 * @since  2.8.1 Check is_admin for Elementor compatibility #726013
		 */
		if ( ! is_admin() ) {
			add_shortcode( 'esi', array( $this, 'shortcode' ) );
		}

	}

	/**
	 * Take over all nonce calls and transform to ESI
	 *
	 * @since  2.9.5
	 */
	private function _transform_nonce() {
		// Load ESI nonces in conf
		$nonces = Conf::val( Base::O_ESI_NONCE );
		add_filter( 'litespeed_esi_nonces', array( Data::get_instance(), 'load_esi_nonces' ) );
		if ( $nonces = apply_filters( 'litespeed_esi_nonces', $nonces ) ) {
			foreach ( $nonces as $action ) {
				$this->nonce_action( $action );
			}
		}

		add_action( 'litespeed_nonce', array( $this, 'nonce_action' ) );

		Debug2::debug( '[ESI] Overwrite wp_create_nonce()' );
		litespeed_define_nonce_func();
	}

	/**
	 * Register a new nonce action to convert it to ESI
	 *
	 * @since  2.9.5
	 */
	public function nonce_action( $action ) {
		// Split the Cache Control
		$action = explode( ' ', $action );
		$control = ! empty( $action[ 1 ] ) ? $action[ 1 ] : '';
		$action = $action[ 0 ];

		// Wildcard supported
		$action = Utility::wildcard2regex( $action );

		if ( array_key_exists( $action, $this->_nonce_actions ) ) {
			return;
		}

		$this->_nonce_actions[ $action ] = $control;

		Debug2::debug( '[ESI] Appended nonce action to nonce list [action] ' . $action );
	}

	/**
	 * Check if an action is registered to replace ESI
	 *
	 * @since 2.9.5
	 */
	public function is_nonce_action( $action ) {
		foreach ( $this->_nonce_actions as $k => $v ) {
			if ( strpos( $k, '*' ) !== false ) {
				if( preg_match( '#' . $k . '#iU', $action ) ) {
					return $v;
				}
			}
			else {
				if ( $k == $action ) {
					return $v;
				}
			}
		}

		return null;
	}

	/**
	 * Shortcode ESI
	 *
	 * @since 2.8
	 * @access public
	 */
	public function shortcode( $atts ) {
		if ( empty( $atts[ 0 ] ) ) {
			Debug2::debug( '[ESI] ===shortcode wrong format', $atts );
			return 'Wrong shortcode esi format';
		}

		$cache = 'public,no-vary';
		if ( ! empty( $atts[ 'cache' ] ) ) {
			$cache = $atts[ 'cache' ];
			unset( $atts[ 'cache' ] );
		}

		do_action( 'litespeed_esi_shortcode-' . $atts[ 0 ] );

		// Show ESI link
		return self::sub_esi_block( 'esi', 'esi-shortcode', $atts, $cache );
	}

	/**
	 * Check if the requested page has esi elements. If so, return esi on
	 * header.
	 *
	 * @since 1.1.3
	 * @access public
	 * @return string Esi On header if request has esi, empty string otherwise.
	 */
	public static function has_esi() {
		return self::$has_esi;
	}

	/**
	 * Sets that the requested page has esi elements.
	 *
	 * @since 1.1.3
	 * @access public
	 */
	public static function set_has_esi() {
		self::$has_esi = true;
	}

	/**
	 * Register all of the hooks related to the esi logic of the plugin.
	 * Specifically when the page IS an esi page.
	 *
	 * @since    1.1.3
	 * @access   private
	 */
	private function _register_esi_actions() {
		! defined( 'LSCACHE_IS_ESI' ) && define( 'LSCACHE_IS_ESI', $_GET[ self::QS_ACTION ] );// Reused this to ESI block ID

		! empty( $_SERVER[ 'ESI_REFERER' ] ) && defined( 'LSCWP_LOG' ) && Debug2::debug( '[ESI] ESI_REFERER: ' . $_SERVER[ 'ESI_REFERER' ] );

		/**
		 * Only when ESI's parent is not REST, replace REQUEST_URI to avoid breaking WP5 editor REST call
		 * @since 2.9.3
		 */
		if ( ! empty( $_SERVER[ 'ESI_REFERER' ] ) && ! REST::get_instance()->is_rest( $_SERVER[ 'ESI_REFERER' ] ) ) {
			$_SERVER[ 'REQUEST_URI' ] = $_SERVER[ 'ESI_REFERER' ];
		}

		if ( ! empty( $_SERVER[ 'ESI_CONTENT_TYPE' ] ) && strpos( $_SERVER[ 'ESI_CONTENT_TYPE' ], 'application/json' ) === 0 ) {
			add_filter( 'litespeed_is_json', '__return_true' );
		}

		/**
		 * Make REST call be able to parse ESI
		 * NOTE: Not effective due to ESI req are all to `/` yet
		 * @since 2.9.4
		 */
		add_action( 'rest_api_init', array( $this, 'load_esi_block' ), 101 );

		// Register ESI blocks
		add_action('litespeed_esi_load-widget', array($this, 'load_widget_block'));
		add_action('litespeed_esi_load-admin-bar', array($this, 'load_admin_bar_block'));
		add_action('litespeed_esi_load-comment-form', array($this, 'load_comment_form_block'));

		add_action('litespeed_esi_load-nonce', array( $this, 'load_nonce_block' ) );
		add_action('litespeed_esi_load-esi', array( $this, 'load_esi_shortcode' ) );

		add_action('litespeed_esi_load-' . self::COMBO, array( $this, 'load_combo' ) );
	}

	/**
	 * Hooked to the template_include action.
	 * Selects the esi template file when the post type is a LiteSpeed ESI page.
	 *
	 * @since 1.1.3
	 * @access public
	 * @param string $template The template path filtered.
	 * @return string The new template path.
	 */
	public function esi_template( $template ) {
		// Check if is an ESI request
		if ( defined( 'LSCACHE_IS_ESI' ) ) {
			Debug2::debug( '[ESI] calling template' );

			return LSCWP_DIR . 'tpl/esi.tpl.php';
		}
		$this->_register_not_esi_actions();
		return $template;
	}

	/**
	 * Register all of the hooks related to the esi logic of the plugin.
	 * Specifically when the page is NOT an esi page.
	 *
	 * @since    1.1.3
	 * @access   private
	 */
	private function _register_not_esi_actions() {
		do_action( 'litespeed_tpl_normal' );

		if ( ! Control::is_cacheable() ) {
			return;
		}

		if ( Router::is_ajax() ) {
			return;
		}

		add_filter('widget_display_callback', array( $this, 'sub_widget_block' ), 0, 3);

		// Add admin_bar esi
		if ( Router::is_logged_in() ) {
			remove_action('wp_footer', 'wp_admin_bar_render', 1000);
			add_action('wp_footer', array($this, 'sub_admin_bar_block'), 1000);
		}

		// Add comment forum esi for logged-in user or commenter
		if ( ! Router::is_ajax() && Vary::has_vary() ) {
			add_filter( 'comment_form_defaults', array( $this, 'register_comment_form_actions' ) );
		}

	}

	/**
	 * Set an ESI to be combine='sub'
	 *
	 * @since  3.4.2
	 */
	public static function combine( $block_id ) {
		if ( ! isset( $_SERVER[ 'X-LSCACHE' ] ) || strpos( $_SERVER[ 'X-LSCACHE' ], 'combine' ) === false ) {
			return;
		}

		if ( in_array( $block_id, self::$_combine_ids ) ) {
			return;
		}

		self::$_combine_ids[] = $block_id;
	}

	/**
	 * Load combined ESI
	 *
	 * @since  3.4.2
	 */
	public function load_combo() {
		Control::set_nocache( 'ESI combine request' );

		if ( empty( $_POST[ 'esi_include' ] ) ) {
			return;
		}

		self::set_has_esi();

		Debug2::debug( '[ESI] 🍔 Load combo', $_POST[ 'esi_include' ] );

		$output = '';
		foreach ( $_POST[ 'esi_include' ] as $url ) {
			$qs = parse_url( htmlspecialchars_decode( $url ), PHP_URL_QUERY );
			parse_str( $qs, $qs );
			if ( empty( $qs[ self::QS_ACTION ] ) ) {
				continue;
			}
			$esi_id = $qs[ self::QS_ACTION ];
			$esi_param = ! empty( $qs[ self::QS_PARAMS ] ) ? $this->_parse_esi_param( $qs[ self::QS_PARAMS ] ) : false;
			$inline_param = apply_filters( 'litespeed_esi_inline-' . $esi_id, array(), $esi_param ); // Returned array need to be [ val, control, tag ]
			if ( $inline_param ) {
				$output .= self::_build_inline( $url, $inline_param );
			}
		}

		echo $output;
	}

	/**
	 * Build a whole inline segment
	 *
	 * @since  3.4.2
	 */
	private static function _build_inline( $url, $inline_param ) {
		if ( ! $url || empty( $inline_param[ 'val' ] ) || empty( $inline_param[ 'control' ] ) || empty( $inline_param[ 'tag' ] ) ) {
			return '';
		}

		return "<esi:inline name='$url' cache-control='" . $inline_param[ 'control' ] . "' cache-tag='" . $inline_param[ 'tag' ] . "'>" . $inline_param[ 'val' ] . "</esi:inline>";
	}

	/**
	 * Build the esi url. This method will build the html comment wrapper as well as serialize and encode the parameter array.
	 *
	 * The block_id parameter should contain alphanumeric and '-_' only.
	 *
	 * @since 1.1.3
	 * @access private
	 * @param string $block_id The id to use to display the correct esi block.
	 * @param string $wrapper The wrapper for the esi comments.
	 * @param array $params The esi parameters.
	 * @param string $control The cache control attribute if any.
	 * @param bool $silence If generate wrapper comment or not
	 * @param bool $preserved 	If this ESI block is used in any filter, need to temporarily convert it to a string to avoid the HTML tag being removed/filtered.
	 * @param bool $svar  		If store the value in memory or not, in memory wil be faster
	 * @param array $inline_val 	If show the current value for current request( this can avoid multiple esi requests in first time cache generating process )
	 */
	public static function sub_esi_block( $block_id, $wrapper, $params = array(), $control = 'private,no-vary', $silence = false, $preserved = false, $svar = false, $inline_param = array() ) {
		if ( empty($block_id) || ! is_array($params) || preg_match('/[^\w-]/', $block_id) ) {
			return false;
		}

		if ( $silence ) {
			// Don't add comment to esi block ( orignal for nonce used in tag property data-nonce='esi_block' )
			$params[ '_ls_silence' ] = true;
		}

		if ( REST::get_instance()->is_rest() || REST::get_instance()->is_internal_rest() ) {
			$params[ 'is_json' ] = 1;
		}

		$params = apply_filters( 'litespeed_esi_params', $params, $block_id );
		$control = apply_filters('litespeed_esi_control', $control, $block_id );

		if ( !is_array($params) || !is_string($control) ) {
			defined( 'LSCWP_LOG' ) && Debug2::debug( "[ESI] 🛑 Sub hooks returned Params: \n" . var_export($params, true) . "\ncache control: \n" . var_export($control, true) );

			return false;
		}

		// Build params for URL
		$appended_params = array(
			self::QS_ACTION	=> $block_id,
		);
		if ( ! empty( $control ) ) {
			$appended_params[ '_control' ] = $control;
		}
		if ( $params ) {
			$appended_params[ self::QS_PARAMS ] = base64_encode( json_encode( $params ) );
			Debug2::debug2( '[ESI] param ', $params );
		}

		// Append hash
		$appended_params[ '_hash' ] = self::_gen_esi_md5( $appended_params );

		/**
		 * Escape potential chars
		 * @since 2.9.4
		 */
		$appended_params = array_map( 'urlencode', $appended_params );

		// Generate ESI URL
		$url = add_query_arg( $appended_params, trailingslashit( wp_make_link_relative( home_url() ) ) );

		$output = '';
		if ( $inline_param ) {
			$output .= self::_build_inline( $url, $inline_param );
		}

		$output .= "<esi:include src='$url'";
		if ( ! empty( $control ) ) {
			$output .= " cache-control='$control'";
		}
		if ( $svar ) {
			$output .= " as-var='1'";
		}
		if ( in_array( $block_id, self::$_combine_ids ) ) {
			$output .= " combine='sub'";
		}
		if ( $block_id == self::COMBO && isset( $_SERVER[ 'X-LSCACHE' ] ) && strpos( $_SERVER[ 'X-LSCACHE' ], 'combine' ) !== false ) {
			$output .= " combine='main'";
		}
		$output .= " />";

		if ( ! $silence ) {
			$output = "<!-- lscwp $wrapper -->$output<!-- lscwp $wrapper esi end -->";
		}

		Debug2::debug( "[ESI] 💕  [BLock_ID] $block_id \t[wrapper] $wrapper \t\t[Control] $control" );
		Debug2::debug2( $output );

		self::set_has_esi();

		// Convert to string to avoid html chars filter when using
		// Will reverse the buffer when output in self::finalize()
		if ( $preserved ) {
			$hash = md5( $output );
			self::get_instance()->_esi_preserve_list[ $hash ] = $output;
			Debug2::debug( "[ESI] Preserved to $hash" );

			return $hash;
		}

		return $output;
	}

	/**
	 * Generate ESI hash md5
	 *
	 * @since  2.9.6
	 * @access private
	 */
	private static function _gen_esi_md5( $params ) {
		$keys = array(
			self::QS_ACTION,
			'_control',
			self::QS_PARAMS,
		);

		$str = '';
		foreach ( $keys as $v ) {
			if ( isset( $params[ $v ] ) && is_string( $params[ $v ] ) ) {
				$str .= $params[ $v ];
			}
		}
		Debug2::debug2( '[ESI] md5_string=' . $str );

		return md5( Conf::val( Base::HASH ) . $str );
	}

	/**
	 * Parses the request parameters on an ESI request
	 *
	 * @since 1.1.3
	 * @access private
	 */
	private function _parse_esi_param( $qs_params = false ) {
		$req_params = false;
		if ( $qs_params ) {
			$req_params = $qs_params;
		}
		elseif ( isset( $_REQUEST[ self::QS_PARAMS ] ) ) {
			$req_params = $_REQUEST[ self::QS_PARAMS ];
		}

		if ( ! $req_params ) {
			return false;
		}

		$unencrypted = base64_decode( $req_params );
		if ( $unencrypted === false ) {
			return false;
		}

		Debug2::debug2( '[ESI] parms', $unencrypted );
		// $unencoded = urldecode($unencrypted); no need to do this as $_GET is already parsed
		$params = json_decode( $unencrypted, true );

		return $params;
	}

	/**
	 * Select the correct esi output based on the parameters in an ESI request.
	 *
	 * @since 1.1.3
	 * @access public
	 */
	public function load_esi_block() {
		/**
		 * Validate if is a legal ESI req
		 * @since 2.9.6
		 */
		if ( empty( $_GET[ '_hash' ] ) || self::_gen_esi_md5( $_GET ) != $_GET[ '_hash' ] ) {
			Debug2::debug( '[ESI] ❌ Failed to validate _hash' );
			return;
		}

		$params = $this->_parse_esi_param();

		if ( defined( 'LSCWP_LOG' ) ) {
			$logInfo = '[ESI] ⭕ ';
			if( ! empty( $params[ self::PARAM_NAME ] ) ) {
				$logInfo .= ' Name: ' . $params[ self::PARAM_NAME ] . ' ----- ';
			}
			$logInfo .= ' [ID] ' . LSCACHE_IS_ESI;
			Debug2::debug( $logInfo );
		}

		if ( ! empty( $params[ '_ls_silence' ] ) ) {
			! defined( 'LSCACHE_ESI_SILENCE' ) && define( 'LSCACHE_ESI_SILENCE', true );
		}

		/**
		 * Buffer needs to be JSON format
		 * @since  2.9.4
		 */
		if ( ! empty( $params[ 'is_json' ] ) ) {
			add_filter( 'litespeed_is_json', '__return_true' );
		}

		Tag::add( rtrim( Tag::TYPE_ESI, '.' ) );
		Tag::add( Tag::TYPE_ESI . LSCACHE_IS_ESI );

		// Debug2::debug(var_export($params, true ));

		/**
		 * Handle default cache control 'private,no-vary' for sub_esi_block() 	@ticket #923505
		 *
		 * @since  2.2.3
		 */
		if ( ! empty( $_GET[ '_control' ] ) ) {
			$control = explode( ',', $_GET[ '_control' ] );
			if ( in_array( 'private', $control ) ) {
				Control::set_private();
			}

			if ( in_array( 'no-vary', $control ) ) {
				Control::set_no_vary();
			}
		}

		do_action('litespeed_esi_load-' . LSCACHE_IS_ESI, $params);
	}

// The *_sub_* functions are helpers for the sub_* functions.
// The *_load_* functions are helpers for the load_* functions.

	/**
	 * Loads the default options for default WordPress widgets.
	 *
	 * @since 1.1.3
	 * @access public
	 */
	public static function widget_default_options($options, $widget) {
		if ( ! is_array($options) ) {
			return $options;
		}

		$widget_name = get_class($widget);
		switch ($widget_name) {
			case 'WP_Widget_Recent_Posts' :
			case 'WP_Widget_Recent_Comments' :
				$options[self::WIDGET_O_ESIENABLE] = Base::VAL_OFF;
				$options[self::WIDGET_O_TTL] = 86400;
				break;
			default :
				break;
		}
		return $options;
	}

	/**
	 * Hooked to the widget_display_callback filter.
	 * If the admin configured the widget to display via esi, this function
	 * will set up the esi request and cancel the widget display.
	 *
	 * @since 1.1.3
	 * @access public
	 * @param array $instance Parameter used to build the widget.
	 * @param WP_Widget $widget The widget to build.
	 * @param array $args Parameter used to build the widget.
	 * @return mixed Return false if display through esi, instance otherwise.
	 */
	public function sub_widget_block( $instance, $widget, $args ) {
		// #210407
		if ( ! is_array( $instance ) ) {
			return $instance;
		}

		$name = get_class( $widget );
		if ( ! isset( $instance[ Base::OPTION_NAME ] ) ) {
			return $instance;
		}
		$options = $instance[ Base::OPTION_NAME ];
		if ( ! isset( $options ) || ! $options[ self::WIDGET_O_ESIENABLE ] ) {
			defined( 'LSCWP_LOG' ) && Debug2::debug( 'ESI 0 ' . $name . ': '. ( ! isset( $options ) ? 'not set' : 'set off' ) );

			return $instance;
		}

		$esi_private = $options[ self::WIDGET_O_ESIENABLE ] == Base::VAL_ON2 ? 'private,' : '';

		$params = array(
			self::PARAM_NAME => $name,
			self::PARAM_ID => $widget->id,
			self::PARAM_INSTANCE => $instance,
			self::PARAM_ARGS => $args
		);

		echo self::sub_esi_block( 'widget', 'widget ' . $name, $params, $esi_private . 'no-vary' );

		return false;
	}

	/**
	 * Hooked to the wp_footer action.
	 * Sets up the ESI request for the admin bar.
	 *
	 * @access public
	 * @since 1.1.3
	 * @global type $wp_admin_bar
	 */
	public function sub_admin_bar_block() {
		global $wp_admin_bar;

		if ( ! is_admin_bar_showing() || ! is_object($wp_admin_bar) ) {
			return;
		}

		// To make each admin bar ESI request different for `Edit` button different link
		$params = array(
			'ref' => $_SERVER[ 'REQUEST_URI' ],
		);

		echo self::sub_esi_block( 'admin-bar', 'adminbar', $params );
	}

	/**
	 * Parses the esi input parameters and generates the widget for esi display.
	 *
	 * @access public
	 * @since 1.1.3
	 * @global $wp_widget_factory
	 * @param array $params Input parameters needed to correctly display widget
	 */
	public function load_widget_block( $params ) {
		// global $wp_widget_factory;
		// $widget = $wp_widget_factory->widgets[ $params[ self::PARAM_NAME ] ];
		$option = $params[ self::PARAM_INSTANCE ];
		$option = $option[ Base::OPTION_NAME ];

		// Since we only reach here via esi, safe to assume setting exists.
		$ttl = $option[ self::WIDGET_O_TTL ];
		defined( 'LSCWP_LOG' ) && Debug2::debug( 'ESI widget render: name ' . $params[ self::PARAM_NAME ] . ', id ' . $params[ self::PARAM_ID ] . ', ttl ' . $ttl );
		if ( $ttl == 0 ) {
			Control::set_nocache( 'ESI Widget time to live set to 0' );
		}
		else {
			Control::set_custom_ttl( $ttl );

			if ( $option[ self::WIDGET_O_ESIENABLE ] == Base::VAL_ON2 ) {
				Control::set_private();
			}
			Control::set_no_vary();
			Tag::add( Tag::TYPE_WIDGET . $params[ self::PARAM_ID ] );
		}
		the_widget( $params[ self::PARAM_NAME ], $params[ self::PARAM_INSTANCE ], $params[ self::PARAM_ARGS ] );
	}

	/**
	 * Generates the admin bar for esi display.
	 *
	 * @access public
	 * @since 1.1.3
	 */
	public function load_admin_bar_block( $params ) {

		if ( ! empty( $params[ 'ref' ] ) ) {
			$ref_qs = parse_url( $params[ 'ref' ], PHP_URL_QUERY );
			if ( ! empty( $ref_qs ) ) {
				parse_str( $ref_qs, $ref_qs_arr );

				if ( ! empty( $ref_qs_arr ) ) {
					foreach ( $ref_qs_arr as $k => $v ) {
						$_GET[ $k ] = $v;
					}
				}
			}
		}

		wp_admin_bar_render();
		if ( ! Conf::val( Base::O_ESI_CACHE_ADMBAR ) ) {
			Control::set_nocache( 'build-in set to not cacheable' );
		}
		else {
			Control::set_private();
			Control::set_no_vary();
		}

		defined( 'LSCWP_LOG' ) && Debug2::debug( 'ESI: adminbar ref: ' . $_SERVER[ 'REQUEST_URI' ] );
	}


	/**
	 * Parses the esi input parameters and generates the comment form for esi display.
	 *
	 * @access public
	 * @since 1.1.3
	 * @param array $params Input parameters needed to correctly display comment form
	 */
	public function load_comment_form_block( $params ) {
		comment_form( $params[ self::PARAM_ARGS ], $params[ self::PARAM_ID ] );

		if ( ! Conf::val( Base::O_ESI_CACHE_COMMFORM ) ) {
			Control::set_nocache( 'build-in set to not cacheable' );
		}
		else {
			// by default comment form is public
			if ( Vary::has_vary() ) {
				Control::set_private();
				Control::set_no_vary();
			}
		}
	}

	/**
	 * Generate nonce for certain action
	 *
	 * @access public
	 * @since 2.6
	 */
	public function load_nonce_block( $params ) {
		$action = $params[ 'action' ];

		Debug2::debug( '[ESI] load_nonce_block [action] ' . $action );

		// set nonce TTL to half day
		Control::set_custom_ttl( 43200 );

		if ( Router::is_logged_in() ) {
			Control::set_private();
		}

		if ( function_exists( 'wp_create_nonce_litespeed_esi' ) ) {
			echo wp_create_nonce_litespeed_esi( $action );
		}
		else {
			echo wp_create_nonce( $action );
		}
	}

	/**
	 * Show original shortcode
	 *
	 * @access public
	 * @since 2.8
	 */
	public function load_esi_shortcode( $params ) {
		if ( isset( $params[ 'ttl' ] ) ) {
			if ( ! $params[ 'ttl' ] ) {
				Control::set_nocache( 'ESI shortcode att ttl=0' );
			}
			else {
				Control::set_custom_ttl( $params[ 'ttl' ] );
			}
			unset( $params[ 'ttl' ] );
		}

		// Replace to original shortcode
		$shortcode = $params[ 0 ];
		$atts_ori = array();
		foreach ( $params as $k => $v ) {
			if ( $k === 0 ) {
				continue;
			}

			$atts_ori[] = is_string( $k ) ? "$k='" . addslashes( $v ) . "'" : $v;
		}

		Tag::add( Tag::TYPE_ESI . "esi.$shortcode" );

		// Output original shortcode final content
		echo do_shortcode( "[$shortcode " . implode( ' ', $atts_ori ) . " ]" );
	}

	/**
	 * Hooked to the comment_form_defaults filter.
	 * Stores the default comment form settings.
	 * If sub_comment_form_block is triggered, the output buffer is cleared and an esi block is added. The remaining comment form is also buffered and cleared.
	 * Else there is no need to make the comment form ESI.
	 *
	 * @since 1.1.3
	 * @access public
	 */
	public function register_comment_form_actions( $defaults ) {
		$this->esi_args = $defaults;
		echo GUI::clean_wrapper_begin();
		add_filter( 'comment_form_submit_button', array( $this, 'sub_comment_form_btn' ), 1000, 2 ); // To save the params passed in
		add_action( 'comment_form', array( $this, 'sub_comment_form_block' ), 1000 );
		return $defaults;
	}

	/**
	 * Store the args passed in comment_form for the ESI comment param usage in `$this->sub_comment_form_block()`
	 *
	 * @since  3.4
	 * @access public
	 */
	public function sub_comment_form_btn( $unused, $args ) {
		if ( empty( $args ) || empty( $this->esi_args ) ) {
			Debug2::debug( 'comment form args empty?' );
			return $unused;
		}
		$esi_args = array();

		// compare current args with default ones
		foreach ( $args as $k => $v ) {
			if ( ! isset( $this->esi_args[ $k ] ) ) {
				$esi_args[ $k ] = $v;
			}
			elseif ( is_array( $v ) ) {
				$diff = array_diff_assoc( $v, $this->esi_args[ $k ] );
				if ( ! empty( $diff ) ) {
					$esi_args[ $k ] = $diff;
				}
			}
			elseif ( $v !== $this->esi_args[ $k ] ) {
				$esi_args[ $k ] = $v;
			}
		}

		$this->esi_args = $esi_args;

		return $unused;
	}

	/**
	 * Hooked to the comment_form_submit_button filter.
	 *
	 * This method will compare the used comment form args against the default args. The difference will be passed to the esi request.
	 *
	 * @access public
	 * @since 1.1.3
	 */
	public function sub_comment_form_block( $post_id ) {
		echo GUI::clean_wrapper_end();
		$params = array(
			self::PARAM_ID => $post_id,
			self::PARAM_ARGS => $this->esi_args,
		);

		echo self::sub_esi_block( 'comment-form', 'comment form', $params );
		echo GUI::clean_wrapper_begin();
		add_action( 'comment_form_after', array( $this, 'comment_form_sub_clean' ) );
	}

	/**
	 * Hooked to the comment_form_after action.
	 * Cleans up the remaining comment form output.
	 *
	 * @since 1.1.3
	 * @access public
	 */
	public function comment_form_sub_clean() {
		echo GUI::clean_wrapper_end();
	}

	/**
	 * Replace preseved blocks
	 *
	 * @since  2.6
	 * @access public
	 */
	public static function finalize( $buffer ) {
		$instance = self::get_instance();

		// Prepend combo esi block
		if ( self::$_combine_ids ) {
			Debug2::debug( '[ESI] 🍔 Enabled combo' );
			$esi_block = self::sub_esi_block( self::COMBO, '__COMBINE_MAIN__', array(), 'no-cache', true );
			$buffer = $esi_block . $buffer;
		}

		// Bypass if no preserved list to be replaced
		if ( ! $instance->_esi_preserve_list ) {
			return $buffer;
		}

		$keys = array_keys( $instance->_esi_preserve_list );

		Debug2::debug( '[ESI] replacing preserved blocks', $keys );

		$buffer = str_replace( $keys, $instance->_esi_preserve_list, $buffer );

		return $buffer;
	}

	/**
	 * Check if the content contains preserved list or not
	 *
	 * @since  3.3
	 */
	public function contain_preserve_esi( $content ) {
		$hit_list = array();
		foreach ( $this->_esi_preserve_list as $k => $v ) {
			if ( strpos( $content, '"' . $k . '"' ) !== false ) {
				$hit_list[] = '"' . $k . '"';
			}
			if ( strpos( $content, "'" . $k . "'" ) !== false ) {
				$hit_list[] = "'" . $k . "'";
			}
		}
		return $hit_list;
	}

}
