<?php
/**
 * The class to optimize image.
 *
 * @since 		2.0
 * @package    	LiteSpeed
 * @subpackage 	LiteSpeed/src
 * @author     	LiteSpeed Technologies <info@litespeedtech.com>
 */
namespace LiteSpeed;
defined( 'WPINC' ) || exit;

class Img_Optm extends Base {
	const CLOUD_ACTION_NEW_REQ = 'new_req';
	const CLOUD_ACTION_TAKEN = 'taken';
	const CLOUD_ACTION_REQUEST_DESTROY = 'imgoptm_destroy';
	const CLOUD_ACTION_CLEAN = 'clean';

	const TYPE_NEW_REQ = 'new_req';
	const TYPE_RESCAN = 'rescan';
	const TYPE_DESTROY = 'destroy';
	const TYPE_CLEAN = 'clean';
	const TYPE_PULL = 'pull';
	const TYPE_BATCH_SWITCH_ORI = 'batch_switch_ori';
	const TYPE_BATCH_SWITCH_OPTM = 'batch_switch_optm';
	const TYPE_CALC_BKUP = 'calc_bkup';
	const TYPE_RESET_ROW = 'reset_row';
	const TYPE_RM_BKUP = 'rm_bkup';

	const STATUS_RAW 		= 0; // 'raw';
	const STATUS_REQUESTED 	= 3; // 'requested';
	const STATUS_NOTIFIED 	= 6; // 'notified';
	const STATUS_DUPLICATED 	= 8; // 'duplicated';
	const STATUS_PULLED 		= 9; // 'pulled';
	const STATUS_FAILED 		= -1; //'failed';
	const STATUS_MISS 		= -3; // 'miss';
	const STATUS_ERR_FETCH 	= -5; // 'err_fetch';
	const STATUS_ERR_404 	= -6; // 'err_404';
	const STATUS_ERR_OPTM 	= -7; // 'err_optm';
	const STATUS_XMETA 		= -8; // 'xmeta';
	const STATUS_ERR 		= -9; // 'err';
	const DB_SIZE = 'litespeed-optimize-size';

	const DB_NEED_PULL = 'need_pull';

	private $wp_upload_dir;
	private $tmp_pid;
	private $tmp_path;
	private $_img_in_queue = array();
	private $_img_in_queue_missed = array();
	private $_existed_src_list = array();
	private $_table_img_optm;
	private $_table_img_optming;
	private $_cron_ran = false;

	private $__media;
	protected $_summary;

	/**
	 * Init
	 *
	 * @since  2.0
	 */
	public function __construct() {
		Debug2::debug2( '[ImgOptm] init' );

		$this->wp_upload_dir = wp_upload_dir();
		$this->__media = $this->cls( 'Media' );
		$this->_table_img_optm = $this->cls( 'Data' )->tb( 'img_optm' );
		$this->_table_img_optming = $this->cls( 'Data' )->tb( 'img_optming' );

		$this->_summary = self::get_summary();
	}

	/**
	 * Gather images auto when update attachment meta
	 *
	 * @since  4.0
	 */
	public function wp_update_attachment_metadata( $meta_value, $post_id ) {
		global $wpdb;

		Debug2::debug2( '[ImgOptm] 🖌️ Auto update attachment meta [id] ' . $post_id );

		if ( empty( $meta_value[ 'file' ] ) ) {
			return;
		}

		// Load gathered images
		if ( ! $this->_existed_src_list ) { // To aavoid extra query when recalling this function
			Debug2::debug( '[Img_Optm] SELECT src from img_optm table' );
			$q = "SELECT src FROM `$this->_table_img_optm` WHERE post_id = %d";
			$list = $wpdb->get_results( $wpdb->prepare( $q, $post_id ) );
			foreach ( $list as $v ) {
				$this->_existed_src_list[] = $post_id . '.' . $v->src;
			}
		}

		// Prepare images
		$this->tmp_pid = $post_id;
		$this->tmp_path = pathinfo( $meta_value[ 'file' ], PATHINFO_DIRNAME ) . '/';
		$this->_append_img_queue( $meta_value, true );
		if ( ! empty( $meta_value[ 'sizes' ] ) ) {
			array_map( array( $this, '_append_img_queue' ), $meta_value[ 'sizes' ] );
		}

		// Save missed images into img_optm
		$this->_save_err_missed();

		if ( ! $this->_img_in_queue ) {
			Debug2::debug( '[Img_Optm] auto update attachment meta 2 bypass: empty _img_in_queue' );
			return;
		}

		// Save to DB
		$this->_save_raw();
	}

	/**
	 * This will gather latest certain images from wp_posts to litespeed_img_optm
	 *
	 * @since  3.0
	 * @access private
	 */
	private function _gather_images() {
		global $wpdb;

		$this->cls( 'Data' )->tb_create( 'img_optm' );
		$this->cls( 'Data' )->tb_create( 'img_optming' );

		// Get images
		$q = "SELECT b.post_id, b.meta_value
			FROM `$wpdb->posts` a
			LEFT JOIN `$wpdb->postmeta` b ON b.post_id = a.ID AND b.meta_key = '_wp_attachment_metadata'
			LEFT JOIN `$this->_table_img_optm` c ON c.post_id = a.ID
			WHERE a.post_type = 'attachment'
				AND a.post_status = 'inherit'
				AND a.post_mime_type IN ('image/jpeg', 'image/png', 'image/gif')
				AND c.id IS NULL
			ORDER BY a.ID DESC
			LIMIT %d
			";
		$q = $wpdb->prepare( $q, apply_filters( 'litespeed_img_gather_max_rows', 200 ) );
		$list = $wpdb->get_results( $q );

		if ( ! $list ) {
			$msg = __( 'No new image gathered.', 'litespeed-cache' );
			Admin_Display::succeed( $msg );

			Debug2::debug( '[Img_Optm] gather_images bypass: no new image found' );
			return;
		}

		foreach ( $list as $v ) {
			$meta_value = $this->_parse_wp_meta_value( $v );
			if ( ! $meta_value ) {
				$this->_save_err_meta( $v->post_id );
				continue;
			}

			$this->tmp_pid = $v->post_id;
			$this->tmp_path = pathinfo( $meta_value[ 'file' ], PATHINFO_DIRNAME ) . '/';
			$this->_append_img_queue( $meta_value, true );
			if ( ! empty( $meta_value[ 'sizes' ] ) ) {
				array_map( array( $this, '_append_img_queue' ), $meta_value[ 'sizes' ] );
			}
		}

		// Save missed images into img_optm
		$this->_save_err_missed();

		if ( ! $this->_img_in_queue ) {
			Debug2::debug( '[Img_Optm] gather_images bypass: empty _img_in_queue' );
			return;
		}

		// Save to DB
		$count = $this->_save_raw();

		$msg = sprintf( __( 'Gathered %d images successfully.', 'litespeed-cache' ), $count );
		Admin_Display::succeed( $msg );
	}

	/**
	 * Add a new img to queue which will be pushed to request
	 *
	 * @since 1.6
	 * @access private
	 */
	private function _append_img_queue( $meta_value, $is_ori_file = false ) {
		if ( empty( $meta_value[ 'file' ] ) || empty( $meta_value[ 'width' ] ) || empty( $meta_value[ 'height' ] ) ) {
			Debug2::debug2( '[Img_Optm] bypass image due to lack of file/w/h: pid ' . $this->tmp_pid, $meta_value );
			return;
		}

		$short_file_path = $meta_value[ 'file' ];

		if ( ! $is_ori_file ) {
			$short_file_path = $this->tmp_path . $short_file_path;
		}

		// Check if src is gathered already or not
		if ( in_array( $this->tmp_pid . '.' . $short_file_path, $this->_existed_src_list ) ) {
			// Debug2::debug2( '[Img_Optm] bypass image due to gathered: pid ' . $this->tmp_pid . ' ' . $short_file_path );
			return;
		}
		else {
			// Append handled images
			$this->_existed_src_list[] = $this->tmp_pid . '.' . $short_file_path;
		}

		// check file exists or not
		$_img_info = $this->__media->info( $short_file_path, $this->tmp_pid );

		if ( ! $_img_info || ! in_array( pathinfo( $short_file_path, PATHINFO_EXTENSION ), array( 'jpg', 'jpeg', 'png', 'gif' ) ) ) {
			$this->_img_in_queue_missed[] = array(
				'pid'	=> $this->tmp_pid,
				'src'	=> $short_file_path,
			);
			Debug2::debug2( '[Img_Optm] bypass image due to file not exist: pid ' . $this->tmp_pid . ' ' . $short_file_path );
			return;
		}

		// Debug2::debug2( '[Img_Optm] adding image: pid ' . $this->tmp_pid );

		$this->_img_in_queue[] = array(
			'pid'	=> $this->tmp_pid,
			'md5'	=> $_img_info[ 'md5' ],
			'url'	=> $_img_info[ 'url' ],
			'src'	=> $short_file_path, // not needed in LiteSpeed IAPI, just leave for local storage after post
			'mime_type'	=> ! empty( $meta_value[ 'mime-type' ] ) ? $meta_value[ 'mime-type' ] : '' ,
			'src_filesize'	=> $_img_info[ 'size' ], // Only used for local storage and calculation
		);
	}

	/**
	 * Save failed to parse meta info
	 *
	 * @since 2.1.1
	 * @access private
	 */
	private function _save_err_meta( $pid ) {
		$data = array(
			$pid,
			self::STATUS_XMETA,
		);
		$this->_insert_img_optm( $data, 'post_id, optm_status' );
		Debug2::debug( '[Img_Optm] Mark wrong meta [pid] ' . $pid );
	}

	/**
	 * Saved non-existed images into img_optm
	 *
	 * @since 2.0
	 * @access private
	 */
	private function _save_err_missed() {
		if ( ! $this->_img_in_queue_missed ) {
			return;
		}

		$count = count( $this->_img_in_queue_missed );
		Debug2::debug( '[Img_Optm] Missed img need to save [total] ' . $count );

		$data_to_add = array();
		foreach ( $this->_img_in_queue_missed as $src_data ) {
			$data_to_add[] = $src_data[ 'pid' ];
			$data_to_add[] = self::STATUS_MISS;
			$data_to_add[] = $src_data[ 'src' ];
		}
		$this->_insert_img_optm( $data_to_add, 'post_id, optm_status, src' );

		$this->_img_in_queue_missed = array();
		return $count;
	}

	/**
	 * Save gathered image raw data
	 *
	 * @since  3.0
	 */
	private function _save_raw() {
		$data = array();
		foreach ( $this->_img_in_queue as $v ) {
			$data[] = $v[ 'pid' ];
			$data[] = self::STATUS_RAW;
			$data[] = $v[ 'src' ];
			$data[] = $v[ 'src_filesize' ];
		}
		$this->_insert_img_optm( $data );

		$count = count( $this->_img_in_queue );
		$this->_img_in_queue = array();

		Debug2::debug( '[Img_Optm] Added raw images [total] ' . $count );

		return $count;
	}

	/**
	 * Insert data into table img_optm
	 *
	 * @since 2.0
	 * @access private
	 */
	private function _insert_img_optm( $data, $fields = 'post_id, optm_status, src, src_filesize' ) {
		if ( empty( $data ) ) {
			return;
		}

		global $wpdb;

		$q = "INSERT INTO `$this->_table_img_optm` ( $fields ) VALUES ";

		// Add placeholder
		$q .= Utility::chunk_placeholder( $data, $fields );

		// Store data
		$wpdb->query( $wpdb->prepare( $q, $data ) );
	}

	/**
	 * Auto send optm request
	 *
	 * @since  2.4.1
	 * @access public
	 */
	public static function cron_auto_request()
	{
		if ( ! defined( 'DOING_CRON' ) ) {
			return false;
		}

		$instance = self::cls();
		$instance->new_req();
	}

	/**
	 * Calculate wet run allowance
	 *
	 * @since 3.0
	 */
	public function wet_limit()
	{
		$wet_limit = 1;
		if ( ! empty( $this->_summary[ 'img_taken' ] ) ) {
			$wet_limit = pow( $this->_summary[ 'img_taken' ], 2 );
		}

		if ( $wet_limit == 1 && ! empty( $this->_summary[ 'img_status.' . self::STATUS_ERR_OPTM ] ) ) {
			$wet_limit = pow( $this->_summary[ 'img_status.' . self::STATUS_ERR_OPTM ], 2 );
		}

		if ( $wet_limit < Cloud::IMG_OPTM_DEFAULT_GROUP ) {
			return $wet_limit;
		}

		// No limit
		return false;
	}

	/**
	 * Check if need to gather at this moment
	 *
	 * @since  3.0
	 */
	public function need_gather()
	{
		global $wpdb;

		if ( ! Data::cls()->tb_exist( 'img_optm' ) || ! Data::cls()->tb_exist( 'img_optming' ) ) {
			Debug2::debug( '[Img_Optm] need gather due to no db tables' );
			return true;
		}

		$q = "SELECT * FROM `$this->_table_img_optm` WHERE optm_status = %d LIMIT 1";
		$q = $wpdb->prepare( $q, self::STATUS_RAW );

		if ( ! $wpdb->get_row( $q ) ) {
			Debug2::debug( '[Img_Optm] need gather due to no new raw image found' );
			return true;
		}

		return false;
	}

	/**
	 * Push raw img to image optm server
	 *
	 * @since 1.6
	 * @access public
	 */
	public function new_req()
	{
		global $wpdb;

		// Check if has credit to push
		$allowance = Cloud::cls()->allowance( Cloud::SVC_IMG_OPTM );

		$wet_limit = $this->wet_limit();

		Debug2::debug( "[Img_Optm] allowance_max $allowance wet_limit $wet_limit" );
		if ( $wet_limit && $wet_limit < $allowance ) {
			$allowance = $wet_limit;
		}

		if ( ! $allowance ) {
			Debug2::debug( '[Img_Optm] ❌ No credit' );
			Admin_Display::error( Error::msg( 'out_of_quota' ) );
			return;
		}

		Debug2::debug( '[Img_Optm] preparing images to push' );

		if ( $this->need_gather() ) {
			$this->_gather_images();
			return;
		}

		$q = "SELECT * FROM `$this->_table_img_optm` WHERE optm_status = %d ORDER BY id LIMIT %d";
		$q = $wpdb->prepare( $q, array( self::STATUS_RAW, $allowance ) );

		$this->_img_in_queue = $wpdb->get_results( $q, ARRAY_A );

		// Limit maximum number of items waiting (status requested) to the allowance
		$q = "SELECT COUNT(1) FROM `$this->_table_img_optming` WHERE optm_status = %d";
		$q = $wpdb->prepare( $q, array( self::STATUS_REQUESTED) );
		$total_requested = $wpdb->get_var( $q );
		$max_requested = $allowance * 1;

		if ( $total_requested > $max_requested ) {
			Debug2::debug( '[Img_Optm] ❌ Too many queued images ('.$total_requested.' > '.$max_requested.')' );
			Admin_Display::error( Error::msg( 'too_many_requested' ) );
			return;
		}

		// Limit maximum number of items waiting to be pulled
		$q = "SELECT COUNT(1) FROM `$this->_table_img_optming` WHERE optm_status = %d";
		$q = $wpdb->prepare( $q, array( self::STATUS_NOTIFIED) );
		$total_notified = $wpdb->get_var( $q );
		$max_notified = $allowance * 5;

		if ( $total_notified > $max_notified ) {
			Debug2::debug( '[Img_Optm] ❌ Too many notified images ('.$total_notified.' > '.$max_notified.')' );
			Admin_Display::error( Error::msg( 'too_many_notified' ) );
			return;
		}

		$num_a = count( $this->_img_in_queue );
		Debug2::debug( '[Img_Optm] Images found: ' . $num_a );
		$this->_filter_duplicated_src();
		$this->_filter_invalid_src();
		$num_b = count( $this->_img_in_queue );
		if ( $num_b != $num_a ) {
			Debug2::debug( '[Img_Optm] Images after filtered duplicated/invalid src: ' . $num_b );
		}

		if ( ! $num_b ) {
			Debug2::debug( '[Img_Optm] No image in queue' );
			return;
		}

		// Push to Cloud server
		$accepted_imgs = $this->_send_request();

		if ( ! $accepted_imgs ) {
			return;
		}

		$placeholder1 = Admin_Display::print_plural( $num_b, 'image' );
		$placeholder2 = Admin_Display::print_plural( $accepted_imgs, 'image' );
		$msg = sprintf( __( 'Pushed %1$s to Cloud server, accepted %2$s.', 'litespeed-cache' ), $placeholder1, $placeholder2 );
		Admin_Display::succeed( $msg );
	}

	/**
	 * Filter duplicated src in work table and $this->_img_in_queue, then mark them as duplicated
	 *
	 * @since 2.0
	 * @access private
	 */
	private function _filter_duplicated_src()
	{
		global $wpdb;

		$srcpath_list = array();

		$list = $wpdb->get_results( "SELECT src FROM $this->_table_img_optming" );
		foreach ( $list as $v ) {
			$srcpath_list[] = $v->src;
		}

		$img_in_queue_duplicated = array();
		foreach ( $this->_img_in_queue as $k => $v ) {
			if ( in_array( $v[ 'src' ], $srcpath_list ) ) {
				$img_in_queue_duplicated[] = $v[ 'id' ];
				unset( $this->_img_in_queue[ $k ] );
				continue;
			}

			$srcpath_list[] = $v[ 'src' ];
		}

		if ( ! $img_in_queue_duplicated ) {
			return;
		}

		$count = count( $img_in_queue_duplicated );
		$msg = sprintf( __( 'Bypassed %1$s duplicated images.', 'litespeed-cache' ), $count );
		Admin_Display::succeed( $msg );

		Debug2::debug( '[Img_Optm] Found duplicated src [total_img_duplicated] ' . $count );

		// Update img table
		$ids = implode( ',', $img_in_queue_duplicated );
		$q = "UPDATE `$this->_table_img_optm` SET optm_status = '" . self::STATUS_DUPLICATED . "' WHERE id IN ( $ids )";
		$wpdb->query( $q );
	}

	/**
	 * Filter the invalid src before sending
	 *
	 * @since 3.0.8.3
	 * @access private
	 */
	private function _filter_invalid_src()
	{
		global $wpdb;

		$img_in_queue_invalid = array();
		foreach ( $this->_img_in_queue as $k => $v ) {
			if ( $v[ 'src' ] ) {
				$extension = pathinfo( $v[ 'src' ], PATHINFO_EXTENSION );
			}
			if ( ! $v[ 'src' ] || empty( $extension ) || ! in_array( $extension, array( 'jpg', 'jpeg', 'png', 'gif' ) ) ) {
				$img_in_queue_invalid[] = $v[ 'id' ];
				unset( $this->_img_in_queue[ $k ] );
				continue;
			}
		}

		if ( ! $img_in_queue_invalid ) {
			return;
		}

		$count = count( $img_in_queue_invalid );
		$msg = sprintf( __( 'Cleared %1$s invalid images.', 'litespeed-cache' ), $count );
		Admin_Display::succeed( $msg );

		Debug2::debug( '[Img_Optm] Found invalid src [total] ' . $count );

		// Update img table
		$ids = implode( ',', $img_in_queue_invalid );
		$q = "DELETE FROM `$this->_table_img_optm` WHERE id IN ( $ids )";
		$wpdb->query( $q );
	}

	/**
	 * Push img request to Cloud server
	 *
	 * @since 1.6.7
	 * @access private
	 */
	private function _send_request()
	{
		global $wpdb;

		$list = array();
		foreach ( $this->_img_in_queue as $v ) {
			$_img_info = $this->__media->info( $v[ 'src' ], $v[ 'post_id' ] );

			if ( empty( $_img_info[ 'url' ] ) || empty( $_img_info[ 'md5' ] ) ) {
				// attachment doesn't exist, delete the record
				$q = "DELETE FROM `$this->_table_img_optm` WHERE post_id = %d";
				$wpdb->query( $wpdb->prepare( $q, $v[ 'post_id' ] ) );
				continue;
			}

			/**
			 * Filter `litespeed_img_optm_options_per_image`
			 * @since 2.4.2
			 */
			/**
			 * To use the filter `litespeed_img_optm_options_per_image` to manipulate `optm_options`, do below:
			 *
			 * 		add_filter( 'litespeed_img_optm_options_per_image', function( $optm_options, $file ){
			 * 			// To add optimize original image
			 * 			if ( Your conditions ) {
			 * 				$optm_options |= API::IMG_OPTM_BM_ORI;
			 * 			}
			 *
			 * 			// To add optimize webp image
			 * 			if ( Your conditions ) {
			 * 				$optm_options |= API::IMG_OPTM_BM_WEBP;
			 * 			}
			 *
			 * 			// To turn on lossless optimize for this image e.g. if filename contains `magzine`
			 * 			if ( strpos( $file, 'magzine' ) !== false ) {
			 * 				$optm_options |= API::IMG_OPTM_BM_LOSSLESS;
			 * 			}
			 *
			 * 			// To set keep exif info for this image
			 * 			if ( Your conditions ) {
			 * 				$optm_options |= API::IMG_OPTM_BM_EXIF;
			 * 			}
			 *
			 *			return $optm_options;
			 *   	} );
			 *
			 */
			$optm_options = apply_filters( 'litespeed_img_optm_options_per_image', 0, $v[ 'src' ] );

			$img = array(
				'id'	=> $v[ 'id' ],
				'url'	=> $_img_info[ 'url' ],
				'md5'	=> $_img_info[ 'md5' ],
			);
			if ( $optm_options ) {
				$img[ 'optm_options' ] = $optm_options;
			}

			$list[] = $img;
		}

		if ( ! $list ) {
			$msg = __( 'No valid image found in the current request.', 'litespeed-cache' );
			Admin_Display::error( $msg );
			return;
		}

		$data = array(
			'action'		=> self::CLOUD_ACTION_NEW_REQ,
			'list' 			=> json_encode( $list ),
			'optm_ori'		=> $this->conf( self::O_IMG_OPTM_ORI ) ? 1 : 0,
			'optm_webp'		=> $this->conf( self::O_IMG_OPTM_WEBP ) ? 1 : 0,
			'optm_lossless'	=> $this->conf( self::O_IMG_OPTM_LOSSLESS ) ? 1 : 0,
			'keep_exif'		=> $this->conf( self::O_IMG_OPTM_EXIF ) ? 1 : 0,
		);

		// Push to Cloud server
		$json = Cloud::post( Cloud::SVC_IMG_OPTM, $data );
		if ( ! $json ) {
			return;
		}

		// Check data format
		if ( empty( $json[ 'ids' ] ) ) {
			Debug2::debug( '[Img_Optm] Failed to parse response data from Cloud server ', $json );
			$msg = __( 'No valid image found by Cloud server in the current request.', 'litespeed-cache' );
			Admin_Display::error( $msg );
			return;
		}

		Debug2::debug( '[Img_Optm] Returned data from Cloud server count: ' . count( $json[ 'ids' ] ) );

		$ids = implode( ',', array_map( 'intval', $json[ 'ids' ] ) );
		// Update img table
		$q = "UPDATE `$this->_table_img_optm` SET optm_status = '" . self::STATUS_REQUESTED . "' WHERE id IN ( $ids )";
		$wpdb->query( $q );

		// Save to work table
		$q = "INSERT INTO `$this->_table_img_optming` ( id, post_id, optm_status, src ) SELECT id, post_id, optm_status, src FROM $this->_table_img_optm WHERE id IN ( $ids )";
		$wpdb->query( $q );

		$this->_summary[ 'last_requested' ] = time();
		self::save_summary();

		return count( $json[ 'ids' ] );
	}

	/**
	 * Cloud server notify Client img status changed
	 *
	 * @since  1.6
	 * @since  1.6.5 Added err/request status free switch
	 * @access public
	 */
	public function notify_img()
	{
		// Interval validation to avoid hacking domain_key
		if ( ! empty( $this->_summary[ 'notify_ts_err' ] ) && time() - $this->_summary[ 'notify_ts_err' ] < 3 ) {
			return Cloud::err( 'too_often' );
		}

		$post_data = json_decode(file_get_contents('php://input'), true);
		if( is_null( $post_data ) ) {
			$post_data = $_POST;
		}

		// Validate key
		if ( empty( $post_data[ 'domain_key' ] ) || $post_data[ 'domain_key' ] !== md5( $this->conf( self::O_API_KEY ) ) ) {
			$this->_summary[ 'notify_ts_err' ] = time();
			self::save_summary();
			return Cloud::err( 'wrong_key' );
		}

		global $wpdb;

		$notified_data = $post_data[ 'data' ];
		if ( empty( $notified_data ) || ! is_array( $notified_data ) ) {
			Debug2::debug( '[Img_Optm] ❌ notify exit: no notified data' );
			return Cloud::err( 'no notified data' );
		}

		if ( empty( $post_data[ 'server' ] ) || substr( $post_data[ 'server' ], -11 ) !== '.quic.cloud' ) {
			Debug2::debug( '[Img_Optm] notify exit: no/wrong server' );
			return Cloud::err( 'no/wrong server' );
		}

		$_allowed_status = array(
			self::STATUS_NOTIFIED, 		// 6 -> 'notified';
			self::STATUS_ERR_FETCH, 	// -5 -> 'err_fetch';
			self::STATUS_ERR_404, 		// -6 -> 'err_404';
			self::STATUS_ERR_OPTM, 		// -7 -> 'err_optm';
			self::STATUS_ERR, 			// -9 -> 'err';
		);

		if ( empty( $post_data[ 'status' ] ) || ! in_array( $post_data[ 'status' ], $_allowed_status ) ) {
			Debug2::debug( '[Img_Optm] notify exit: no/wrong status', $post_data );
			return Cloud::err( 'no/wrong status' );
		}

		$status = $post_data[ 'status' ];

		$last_log_pid = 0;

		if ( empty( $this->_summary[ 'reduced' ] ) ) {
			$this->_summary[ 'reduced' ] = 0;
		}

		if ( $status == self::STATUS_NOTIFIED ) {
			// Notified data format: [ img_optm_id => [ id=>, src_size=>, ori=>, ori_md5=>, ori_reduced=>, webp=>, webp_md5=>, webp_reduced=> ] ]
			$q = "SELECT a.*, b.meta_id as b_meta_id, b.meta_value AS b_optm_info
					FROM `$this->_table_img_optming` a
					LEFT JOIN `$wpdb->postmeta` b ON b.post_id = a.post_id AND b.meta_key = %s
					WHERE a.id IN ( " . implode( ',', array_fill( 0, count( $notified_data ), '%d' ) ) . " )";
			$list = $wpdb->get_results( $wpdb->prepare( $q, array_merge( array( self::DB_SIZE ), array_keys( $notified_data ) ) ) );
			$ls_optm_size_row_exists_postids = array();
			foreach ( $list as $v ) {
				$json = $notified_data[ $v->id ];

				$server = ! empty( $json['server'] ) ? $json['server'] : $post_data['server'];

				$server_info = array(
					'server'	=> $server,
				);

				// Save server side ID to send taken notification after pulled
				$server_info[ 'id' ] = $json[ 'id' ];
				if ( !empty( $json['file_id'] ) ) {
					$server_info['file_id'] = $json['file_id'];
				}

				// Optm info array
				$postmeta_info =  array(
					'ori_total' => 0,
					'ori_saved' => 0,
					'webp_total' => 0,
					'webp_saved' => 0,
				);
				// Init postmeta_info for the first one
				if ( ! empty( $v->b_meta_id ) ) {
					foreach ( maybe_unserialize( $v->b_optm_info ) as $k2 => $v2 ) {
						$postmeta_info[ $k2 ] += $v2;
					}
				}

				if ( ! empty( $json[ 'ori' ] ) ) {
					$server_info[ 'ori_md5' ] = $json[ 'ori_md5' ];
					$server_info[ 'ori' ] = $json[ 'ori' ];

					// Append meta info
					$postmeta_info[ 'ori_total' ] += $json[ 'src_size' ];
					$postmeta_info[ 'ori_saved' ] += $json[ 'ori_reduced' ]; // optimized image size info in img_optm tb will be updated when pull

					$this->_summary[ 'reduced' ] += $json[ 'ori_reduced' ];
				}

				if ( ! empty( $json[ 'webp' ] ) ) {
					$server_info[ 'webp_md5' ] = $json[ 'webp_md5' ];
					$server_info[ 'webp' ] = $json[ 'webp' ];

					// Append meta info
					$postmeta_info[ 'webp_total' ] += $json[ 'src_size' ];
					$postmeta_info[ 'webp_saved' ] += $json[ 'webp_reduced' ];

					$this->_summary[ 'reduced' ] += $json[ 'webp_reduced' ];
				}

				// Update status and data in working table
				$q = "UPDATE `$this->_table_img_optming` SET optm_status = %d, server_info = %s WHERE id = %d ";
				$wpdb->query( $wpdb->prepare( $q, array( $status, json_encode( $server_info ), $v->id ) ) );

				// Update postmeta for optm summary
				$postmeta_info = serialize( $postmeta_info );
				if ( empty( $v->b_meta_id ) && ! in_array( $v->post_id, $ls_optm_size_row_exists_postids ) ) {
					Debug2::debug( '[Img_Optm] New size info [pid] ' . $v->post_id );
					$q = "INSERT INTO `$wpdb->postmeta` ( post_id, meta_key, meta_value ) VALUES ( %d, %s, %s )";
					$wpdb->query( $wpdb->prepare( $q, array( $v->post_id, self::DB_SIZE, $postmeta_info ) ) );
					$ls_optm_size_row_exists_postids[] = $v->post_id;
				}
				else {
					$q = "UPDATE `$wpdb->postmeta` SET meta_value = %s WHERE meta_id = %d ";
					$wpdb->query( $wpdb->prepare( $q, array( $postmeta_info, $v->b_meta_id ) ) );
				}


				// write log
				$pid_log = $last_log_pid == $v->post_id ? '.' : $v->post_id;
				Debug2::debug( '[Img_Optm] notify_img [status] ' . $status . " \t\t[pid] " . $pid_log . " \t\t[id] " . $v->id );
				$last_log_pid = $v->post_id;
			}

			self::save_summary();

			// Mark need_pull tag for cron
			self::update_option( self::DB_NEED_PULL, self::STATUS_NOTIFIED );
		}
		elseif ( $status == self::STATUS_ERR_FETCH ) {
			// Only update working table
			$q = "UPDATE `$this->_table_img_optming` SET optm_status = %d WHERE id IN ( " . implode( ',', array_fill( 0, count( $notified_data ), '%d' ) ) . " ) ";
			$wpdb->query( $wpdb->prepare( $q, array_merge( array( $status ), $notified_data ) ) );
		}
		else { // Other errors will directly update img_optm table and remove the working records

			// Delete from working table
			$q = "DELETE FROM `$this->_table_img_optming` WHERE id IN ( " . implode( ',', array_fill( 0, count( $notified_data ), '%d' ) ) . " ) ";
			$wpdb->query( $wpdb->prepare( $q, $notified_data ) );

			// Update img_optm
			$q = "UPDATE `$this->_table_img_optm` SET optm_status = %d WHERE id IN ( " . implode( ',', array_fill( 0, count( $notified_data ), '%d' ) ) . " ) ";
			$wpdb->query( $wpdb->prepare( $q, array_merge( array( $status ), $notified_data ) ) );

			// Log the failed optm to summary, to be counted in wet_limit
			if ( $status == self::STATUS_ERR_OPTM ) {
				if ( empty( $this->_summary[ 'img_status.' . $status ] ) ) {
					$this->_summary[ 'img_status.' . $status ] = 0;
				}
				$this->_summary[ 'img_status.' . $status ] += count( $notified_data );
				self::save_summary();
			}
		}

		// redo count err

		return Cloud::ok( array( 'count' => count( $notified_data ) ) );
	}

	/**
	 * Cron pull optimized img
	 *
	 * @since  1.6
	 * @access public
	 */
	public static function cron_pull()
	{
		if ( ! defined( 'DOING_CRON' ) ) {
			return;
		}

		Debug2::debug( '[Img_Optm] cron_pull running' );

		$tag = self::get_option( self::DB_NEED_PULL );

		if ( ! $tag || $tag != self::STATUS_NOTIFIED ) {
			Debug2::debug( '[Img_Optm] ❌ no need pull [tag] ' . $tag );
			return;
		}

		self::cls()->pull();
	}

	/**
	 * Pull optimized img
	 *
	 * @since  1.6
	 * @access public
	 */
	public function pull( $manual = false )
	{
		global $wpdb;

		Debug2::debug( '[Img_Optm] ' . ( $manual ? 'Manually' : 'Cron' ) . ' pull started' );

		if ( $this->cron_running() ) {
			Debug2::debug( '[Img_Optm] Pull cron is running' );

			$msg = __( 'Pull Cron is running', 'litespeed-cache' );
			Admin_Display::error( $msg );
			return;
		}

		$q = "SELECT * FROM `$this->_table_img_optming` WHERE optm_status = %d ORDER BY id LIMIT 1";
		$_q = $wpdb->prepare( $q, self::STATUS_NOTIFIED );

		$optm_ori = $this->conf( self::O_IMG_OPTM_ORI );
		$rm_ori_bkup = $this->conf( self::O_IMG_OPTM_RM_BKUP );
		$optm_webp = $this->conf( self::O_IMG_OPTM_WEBP );

		// pull 1 min images each time
		$end_time = time() + 60;

		$total_pulled_ori = 0;
		$total_pulled_webp = 0;
		$beginning = time();

		$server_list = array();

		while ( time() < $end_time ) {
			set_time_limit( 80 );

			$row_img = $wpdb->get_row( $_q );
			if ( ! $row_img ) {
				// No image
				break;
			}

			/**
			 * Update cron timestamp to avoid duplicated running
			 * @since  1.6.2
			 */
			$this->_update_cron_running();

			$local_file = $this->wp_upload_dir[ 'basedir' ] . '/' . $row_img->src;

			// Save ori optm image
			$target_size = 0;

			$server_info = json_decode( $row_img->server_info, true );
			if ( ! empty( $server_info[ 'ori' ] ) ) {
				/**
				 * Use wp orignal get func to avoid allow_url_open off issue
				 * @since  1.6.5
				 */
				$image_url = $server_info[ 'server' ] . '/' . $server_info[ 'ori' ];
				Debug2::debug( '[Img_Optm] Pulling image: ' . $image_url );
				$response = wp_remote_get( $image_url, array( 'timeout' => 60 ) );
				if ( is_wp_error( $response ) ) {
					$error_message = $response->get_error_message();
					Debug2::debug( '[Img_Optm] ❌ failed to pull image: ' . $error_message );
					return;
				}

				if ( $response[ 'response' ][ 'code' ] == 404 ) {
					$this->_step_back_image( $row_img->id );

					$msg = __( 'Some optimized image file(s) has expired and was cleared.', 'litespeed-cache' );
					Admin_Display::error( $msg );
					continue;
				}

				file_put_contents( $local_file . '.tmp', $response[ 'body' ] );

				if ( ! file_exists( $local_file . '.tmp' ) || ! filesize( $local_file . '.tmp' ) || md5_file( $local_file . '.tmp' ) !== $server_info[ 'ori_md5' ] ) {
					Debug2::debug( '[Img_Optm] ❌ Failed to pull optimized img: file md5 mismatch [url] ' . $server_info[ 'server' ] . '/' . $server_info[ 'ori' ] . ' [server_md5] ' . $server_info[ 'ori_md5' ] );

					// Update status to failed
					$q = "UPDATE `$this->_table_img_optm` SET optm_status = %d WHERE id = %d ";
					$wpdb->query( $wpdb->prepare( $q, array( self::STATUS_FAILED, $row_img->id ) ) );
					// Delete working table
					$q = "DELETE FROM `$this->_table_img_optming` WHERE id = %d ";
					$wpdb->query( $wpdb->prepare( $q, $row_img->id ) );

					$msg = __( 'One or more pulled images does not match with the notified image md5', 'litespeed-cache' );
					Admin_Display::error( $msg );
					continue;
				}

				// Backup ori img
				if ( ! $rm_ori_bkup ) {
					$extension = pathinfo( $local_file, PATHINFO_EXTENSION );
					$bk_file = substr( $local_file, 0, -strlen( $extension ) ) . 'bk.' . $extension;
					file_exists( $local_file ) && rename( $local_file, $bk_file );
				}

				// Replace ori img
				rename( $local_file . '.tmp', $local_file );

				Debug2::debug( '[Img_Optm] Pulled optimized img: ' . $local_file );

				$target_size = filesize( $local_file );

				/**
				 * API Hook
				 * @since  2.9.5
				 * @since  3.0 $row_img has less elements now. Most useful ones are `post_id`/`src`
				 */
				do_action( 'litespeed_img_pull_ori', $row_img, $local_file );

				$total_pulled_ori ++;
			}

			// Save webp image
			$webp_size = 0;

			if ( ! empty( $server_info[ 'webp' ] ) ) {
				// Fetch
				$response = wp_remote_get( $server_info[ 'server' ] . '/' . $server_info[ 'webp' ], array( 'timeout' => 60 ) );
				if ( is_wp_error( $response ) ) {
					$error_message = $response->get_error_message();
					Debug2::debug( '[Img_Optm] failed to pull webp image: ' . $error_message );
					return;
				}

				if ( $response[ 'response' ][ 'code' ] == 404 ) {
					$this->_step_back_image( $row_img->id );

					$msg = __( 'Optimized WebP file expired and was cleared.', 'litespeed-cache' );
					Admin_Display::error( $msg );
					return;
				}

				file_put_contents( $local_file . '.webp', $response[ 'body' ] );

				if ( ! file_exists( $local_file . '.webp' ) || ! filesize( $local_file . '.webp' ) || md5_file( $local_file . '.webp' ) !== $server_info[ 'webp_md5' ] ) {
					Debug2::debug( '[Img_Optm] ❌ Failed to pull optimized webp img: file md5 mismatch, server md5: ' . $server_info[ 'webp_md5' ] );

					// update status to failed
					$q = "UPDATE `$this->_table_img_optm` SET optm_status = %d WHERE id = %d ";
					$wpdb->query( $wpdb->prepare( $q, array( self::STATUS_FAILED, $row_img->id ) ) );
					// Delete working table
					$q = "DELETE FROM `$this->_table_img_optming` WHERE id = %d ";
					$wpdb->query( $wpdb->prepare( $q, $row_img->id ) );

					$msg = __( 'Pulled WebP image md5 does not match the notified WebP image md5.', 'litespeed-cache' );
					Admin_Display::error( $msg );
					return;
				}

				Debug2::debug( '[Img_Optm] Pulled optimized img WebP: ' . $local_file . '.webp' );

				$webp_size = filesize( $local_file . '.webp' );

				/**
				 * API for WebP
				 * @since 2.9.5
				 * @since  3.0 $row_img less elements (see above one)
				 * @see #751737  - API docs for WEBP generation
				 */
				do_action( 'litespeed_img_pull_webp', $row_img, $local_file . '.webp' );

				$total_pulled_webp ++;
			}

			Debug2::debug2( '[Img_Optm] Update _table_img_optm record [id] ' . $row_img->id );

			// Update pulled status
			$q = "UPDATE `$this->_table_img_optm` SET optm_status = %d, target_filesize = %d, webp_filesize = %d WHERE id = %d ";
			$wpdb->query( $wpdb->prepare( $q, array( self::STATUS_PULLED, $target_size, $webp_size, $row_img->id ) ) );
			// Delete working table
			$q = "DELETE FROM `$this->_table_img_optming` WHERE id = %d ";
			$wpdb->query( $wpdb->prepare( $q, $row_img->id ) );

			// Save server_list to notify taken
			if ( empty( $server_list[ $server_info[ 'server' ] ] ) ) {
				$server_list[ $server_info[ 'server' ] ] = array();
			}

			$server_info_id = ! empty( $server_info['file_id'] ) ? $server_info['file_id'] : $server_info['id'];
			$server_list[ $server_info[ 'server' ] ][] = $server_info_id;
		}

		// Notify IAPI images taken
		foreach ( $server_list as $server => $img_list ) {
			$data = array(
				'action'	=> self::CLOUD_ACTION_TAKEN,
				'list' 		=> $img_list,
				'server'	=> $server,
			);
			// TODO: improve this so we do not call once per server, but just once and then filter on the server side
			Cloud::post( Cloud::SVC_IMG_OPTM, $data );
		}

		if ( empty( $this->_summary[ 'img_taken' ] ) ) {
			$this->_summary[ 'img_taken' ] = 0;
		}
		$this->_summary[ 'img_taken' ] += $total_pulled_ori + $total_pulled_webp;
		self::save_summary();

		// Manually running needs to roll back timestamp for next running
		if ( $manual ) {
			$this->_update_cron_running( true ) ;
		}

		$msg = sprintf( __( 'Pulled %d image(s)', 'litespeed-cache' ), $total_pulled_ori + $total_pulled_webp );
		Admin_Display::succeed( $msg );

		// Check if there is still task in queue
		$q = "SELECT * FROM `$this->_table_img_optming` WHERE optm_status = %d LIMIT 1";
		$to_be_continued = $wpdb->get_row( $wpdb->prepare( $q, self::STATUS_NOTIFIED ) );
		if ( $to_be_continued ) {
			Debug2::debug( '[Img_Optm] Task in queue, to be continued...' );
			return Router::self_redirect( Router::ACTION_IMG_OPTM, self::TYPE_PULL );
		}

		// If all pulled, update tag to done
		Debug2::debug( '[Img_Optm] Marked pull status to all pulled' );
		self::update_option( self::DB_NEED_PULL, self::STATUS_PULLED );
	}

	/**
	 * Push image back to previous status
	 *
	 * @since  3.0
	 * @access private
	 */
	private function _step_back_image( $id )
	{
		global $wpdb;

		// Reset the image to gathered status
		$q = "UPDATE `$this->_table_img_optm` SET optm_status = %d WHERE id = %d ";
		$wpdb->query( $wpdb->prepare( $q, array( self::STATUS_RAW, $id ) ) );
		// Delete working table
		$q = "DELETE FROM `$this->_table_img_optming` WHERE id = %d ";
		$wpdb->query( $wpdb->prepare( $q, $id ) );
	}

	/**
	 * Parse wp's meta value
	 *
	 * @since 1.6.7
	 * @access private
	 */
	private function _parse_wp_meta_value( $v )
	{
		if ( ! $v->meta_value ) {
			Debug2::debug( '[Img_Optm] bypassed parsing meta due to no meta_value: pid ' . $v->post_id ) ;
			return false ;
		}

		$meta_value = @maybe_unserialize( $v->meta_value ) ;
		if ( ! is_array( $meta_value ) ) {
			Debug2::debug( '[Img_Optm] bypassed parsing meta due to meta_value not json: pid ' . $v->post_id ) ;
			return false ;
		}

		if ( empty( $meta_value[ 'file' ] ) ) {
			Debug2::debug( '[Img_Optm] bypassed parsing meta due to no ori file: pid ' . $v->post_id ) ;
			return false ;
		}

		return $meta_value ;
	}

	/**
	 * Clean up all unfinished queue locally and to Cloud server
	 *
	 * @since 2.1.2
	 * @access public
	 */
	public function clean()
	{
		global $wpdb ;

		if ( ! Data::cls()->tb_exist( 'img_optm' ) ) {
			return;
		}

		// Clear local working table queue
		if ( Data::cls()->tb_exist( 'img_optming' ) ) {
			$q = "TRUNCATE `$this->_table_img_optming`";
			$wpdb->query( $q );
		}

		// Reset img_optm table's queue
		if ( Data::cls()->tb_exist( 'img_optm' ) ) {
			$q = "UPDATE `$this->_table_img_optm` SET optm_status = %d WHERE optm_status = %d" ;
			$wpdb->query( $wpdb->prepare( $q, self::STATUS_RAW, self::STATUS_REQUESTED ) ) ;
		}

		$msg = __( 'Cleaned up unfinished data successfully.', 'litespeed-cache' ) ;
		Admin_Display::succeed( $msg ) ;
	}

	/**
	 * Destroy all optimized images
	 *
	 * @since 3.0
	 * @access private
	 */
	private function _destroy()
	{
		global $wpdb ;

		if ( ! Data::cls()->tb_exist( 'img_optm' ) ) {
			Debug2::debug( '[Img_Optm] DESTROY bypassed due to table not exist' ) ;
			return;
		}

		Debug2::debug( '[Img_Optm] excuting DESTROY process' ) ;

		/**
		 * Limit images each time before redirection to fix Out of memory issue. #665465
		 * @since  2.9.8
		 */
		// Start deleting files
		$limit = apply_filters( 'litespeed_imgoptm_destroy_max_rows', 500 ) ;
		$q = "SELECT src,post_id FROM `$this->_table_img_optm` WHERE optm_status = %d ORDER BY id LIMIT %d" ;
		$list = $wpdb->get_results( $wpdb->prepare( $q, self::STATUS_PULLED, $limit ) ) ;
		foreach ( $list as $v ) {
			// del webp
			$this->__media->info( $v->src . '.webp', $v->post_id ) && $this->__media->del( $v->src . '.webp', $v->post_id ) ;
			$this->__media->info( $v->src . '.optm.webp', $v->post_id ) && $this->__media->del( $v->src . '.optm.webp', $v->post_id ) ;

			$extension = pathinfo( $v->src, PATHINFO_EXTENSION ) ;
			$local_filename = substr( $v->src, 0, - strlen( $extension ) - 1 ) ;
			$bk_file = $local_filename . '.bk.' . $extension ;
			$bk_optm_file = $local_filename . '.bk.optm.' . $extension ;

			// del optimized ori
			if ( $this->__media->info( $bk_file, $v->post_id ) ) {
				$this->__media->del( $v->src, $v->post_id ) ;
				$this->__media->rename( $bk_file, $v->src, $v->post_id ) ;
			}
			$this->__media->info( $bk_optm_file, $v->post_id ) && $this->__media->del( $bk_optm_file, $v->post_id ) ;
		}

		// Check if there are more images, then return `to_be_continued` code
		$q = "SELECT COUNT(*) FROM `$this->_table_img_optm` WHERE optm_status = %d" ;
		$total_img = $wpdb->get_var( $wpdb->prepare( $q, self::STATUS_PULLED ) ) ;
		if ( $total_img > $limit ) {
			$q = "DELETE FROM `$this->_table_img_optm` WHERE optm_status = %d ORDER BY id LIMIT %d" ;
			$wpdb->query( $wpdb->prepare( $q, self::STATUS_PULLED, $limit ) ) ;

			Debug2::debug( '[Img_Optm] To be continued 🚦' ) ;

			return Router::self_redirect( Router::ACTION_IMG_OPTM, self::TYPE_DESTROY );
		}

		// Delete postmeta info
		$q = "DELETE FROM `$wpdb->postmeta` WHERE meta_key = %s" ;
		$wpdb->query( $wpdb->prepare( $q, self::DB_SIZE ) ) ;

		// Delete img_optm table
		Data::cls()->tb_del( 'img_optm' ) ;
		Data::cls()->tb_del( 'img_optming' ) ;

		// Clear options table summary info
		self::delete_option( '_summary' ) ;
		self::delete_option( self::DB_NEED_PULL ) ;

		$msg = __( 'Destroy all optimization data successfully.', 'litespeed-cache' ) ;
		Admin_Display::succeed( $msg ) ;
	}

	/**
	 * Rescan to find new generated images
	 *
	 * @since 1.6.7
	 * @access private
	 */
	private function _rescan() {
		global $wpdb;

		$offset = ! empty( $_GET[ 'litespeed_i' ] ) ? $_GET[ 'litespeed_i' ] : 0;
		$limit = 500;

		Debug2::debug( '[Img_Optm] rescan images' );

		// Get images
		$q = "SELECT b.post_id, b.meta_value
			FROM `$wpdb->posts` a, `$wpdb->postmeta` b
			WHERE a.post_type = 'attachment'
				AND a.post_status = 'inherit'
				AND a.post_mime_type IN ('image/jpeg', 'image/png', 'image/gif')
				AND a.ID = b.post_id
				AND b.meta_key = '_wp_attachment_metadata'
			ORDER BY a.ID
			LIMIT %d, %d
			";
		$list = $wpdb->get_results( $wpdb->prepare( $q, $offset * $limit, $limit + 1 ) ); // last one is the seed for next batch

		if ( ! $list ) {
			$msg = __( 'Rescanned successfully.', 'litespeed-cache' );
			Admin_Display::succeed( $msg );

			Debug2::debug( '[Img_Optm] rescan bypass: no gathered image found' );
			return;
		}

		if ( count( $list ) == $limit + 1 ) {
			$to_be_continued = true;
			array_pop( $list ); // last one is the seed for next round, discard here.
		} else {
			$to_be_continued = false;
		}

		// Prepare post_ids to inquery gathered images
		$pid_set = array();
		$scanned_list = array();
		foreach ( $list as $v ) {
			$meta_value = $this->_parse_wp_meta_value( $v );
			if ( ! $meta_value ) {
				continue;
			}

			$scanned_list[] = array(
				'pid' => $v->post_id,
				'meta' => $meta_value,
			);

			$pid_set[] = $v->post_id;
		}

		// Build gathered images
		$q = "SELECT src, post_id FROM `$this->_table_img_optm` WHERE post_id IN (" . implode( ',', array_fill( 0, count( $pid_set ), '%d' ) ) . ")";
		$list = $wpdb->get_results( $wpdb->prepare( $q, $pid_set ) );
		foreach ( $list as $v ) {
			$this->_existed_src_list[] = $v->post_id . '.' . $v->src;
		}

		// Find new images
		foreach ( $scanned_list as $v ) {
			$meta_value = $v[ 'meta' ];
			// Parse all child src and put them into $this->_img_in_queue, missing ones to $this->_img_in_queue_missed
			$this->tmp_pid = $v[ 'pid' ];
			$this->tmp_path = pathinfo( $meta_value[ 'file' ], PATHINFO_DIRNAME ) . '/';
			$this->_append_img_queue( $meta_value, true );
			if ( ! empty( $meta_value[ 'sizes' ] ) ) {
				array_map( array( $this, '_append_img_queue' ), $meta_value[ 'sizes' ] );
			}
		}

		Debug2::debug( '[Img_Optm] rescaned [img_missed] ' . count( $this->_img_in_queue_missed ) . ' [img] ' . count( $this->_img_in_queue ) );

		// Save missed images into img_optm
		$this->_save_err_missed();

		$count = count( $this->_img_in_queue );
		if ( $count > 0 ) {
			// Save to DB
			$this->_save_raw();
		}

		if ( $to_be_continued ) {
			return Router::self_redirect( Router::ACTION_IMG_OPTM, self::TYPE_RESCAN );
		}

		$msg = $count ? sprintf( __( 'Rescanned %d images successfully.', 'litespeed-cache' ), $count ) : __( 'Rescanned successfully.', 'litespeed-cache' );
		Admin_Display::succeed( $msg );
	}

	/**
	 * Calculate bkup original images storage
	 *
	 * @since 2.2.6
	 * @access private
	 */
	private function _calc_bkup()
	{
		global $wpdb;

		if ( ! Data::cls()->tb_exist( 'img_optm' ) ) {
			return;
		}

		$offset = ! empty( $_GET[ 'litespeed_i' ] ) ? $_GET[ 'litespeed_i' ] : 0;
		$limit = 500;

		if ( ! $offset ) {
			$this->_summary[ 'bk_summary' ] = array(
				'date' => time(),
				'count' => 0,
				'sum' => 0,
			);
		}

		$q = "SELECT src,post_id FROM `$this->_table_img_optm` WHERE optm_status = %d ORDER BY id LIMIT %d, %d";
		$list = $wpdb->get_results( $wpdb->prepare( $q, array( self::STATUS_PULLED, $offset * $limit, $limit ) ) );

		foreach ( $list as $v ) {
			$extension = pathinfo( $v->src, PATHINFO_EXTENSION );
			$local_filename = substr( $v->src, 0, - strlen( $extension ) - 1 );
			$bk_file = $local_filename . '.bk.' . $extension;

			$img_info = $this->__media->info( $bk_file, $v->post_id );
			if ( ! $img_info ) {
				continue;
			}

			$this->_summary[ 'bk_summary' ][ 'count' ] ++;
			$this->_summary[ 'bk_summary' ][ 'sum' ] += $img_info[ 'size' ];
		}

		$this->_summary[ 'bk_summary' ][ 'date' ] = time();
		self::save_summary();

		Debug2::debug( '[Img_Optm] _calc_bkup total: ' . $this->_summary[ 'bk_summary' ][ 'count' ] . ' [size] ' . $this->_summary[ 'bk_summary' ][ 'sum' ] );

		$offset ++;
		$q = "SELECT src,post_id FROM `$this->_table_img_optm` WHERE optm_status = %d ORDER BY id LIMIT %d, %d";
		$to_be_continued = $wpdb->get_row( $wpdb->prepare( $q, array( self::STATUS_PULLED, $offset * $limit, 1 ) ) );

		if ( $to_be_continued ) {
			return Router::self_redirect( Router::ACTION_IMG_OPTM, self::TYPE_CALC_BKUP );
		}

		$msg = __( 'Calculated backups successfully.', 'litespeed-cache' );
		Admin_Display::succeed( $msg );
	}

	/**
	 * Delete bkup original images storage
	 *
	 * @since  2.5
	 * @access public
	 */
	public function rm_bkup()
	{
		global $wpdb;

		if ( ! Data::cls()->tb_exist( 'img_optm' ) ) {
			return;
		}

		$offset = ! empty( $_GET[ 'litespeed_i' ] ) ? $_GET[ 'litespeed_i' ] : 0;
		$limit = 500;

		if ( empty( $this->_summary[ 'rmbk_summary' ] ) ) {
			$this->_summary[ 'rmbk_summary' ] = array(
				'date' => time(),
				'count' => 0,
				'sum' => 0,
			);
		}

		$q = "SELECT src,post_id FROM `$this->_table_img_optm` WHERE optm_status = %d ORDER BY id LIMIT %d, %d";
		$list = $wpdb->get_results( $wpdb->prepare( $q, array( self::STATUS_PULLED, $offset * $limit, $limit ) ) );

		foreach ( $list as $v ) {
			$extension = pathinfo( $v->src, PATHINFO_EXTENSION );
			$local_filename = substr( $v->src, 0, - strlen( $extension ) - 1 );
			$bk_file = $local_filename . '.bk.' . $extension;

			// Del ori file
			$img_info = $this->__media->info( $bk_file, $v->post_id );
			if ( ! $img_info ) {
				continue;
			}

			$this->_summary[ 'rmbk_summary' ][ 'count' ] ++;
			$this->_summary[ 'rmbk_summary' ][ 'sum' ] += $img_info[ 'size' ];

			$this->__media->del( $bk_file, $v->post_id );
		}

		$this->_summary[ 'rmbk_summary' ][ 'date' ] = time();
		self::save_summary();

		Debug2::debug( '[Img_Optm] rm_bkup total: ' . $this->_summary[ 'rmbk_summary' ][ 'count' ] . ' [size] ' . $this->_summary[ 'rmbk_summary' ][ 'sum' ] );

		$offset ++;
		$q = "SELECT src,post_id FROM `$this->_table_img_optm` WHERE optm_status = %d ORDER BY id LIMIT %d, %d";
		$to_be_continued = $wpdb->get_row( $wpdb->prepare( $q, array( self::STATUS_PULLED, $offset * $limit, 1 ) ) );

		if ( $to_be_continued ) {
			return Router::self_redirect( Router::ACTION_IMG_OPTM, self::TYPE_RM_BKUP );
		}

		$msg = __( 'Removed backups successfully.', 'litespeed-cache' );
		Admin_Display::succeed( $msg );
	}

	/**
	 * Count images
	 *
	 * @since 1.6
	 * @access public
	 */
	public function img_count()
	{
		global $wpdb;

		$tb_existed = Data::cls()->tb_exist( 'img_optm' );
		$tb_existed2 = Data::cls()->tb_exist( 'img_optming' );

		$q = "SELECT COUNT(*)
			FROM `$wpdb->posts` a
			LEFT JOIN `$wpdb->postmeta` b ON b.post_id = a.ID AND b.meta_key = '_wp_attachment_metadata'
			WHERE a.post_type = 'attachment'
				AND a.post_status = 'inherit'
				AND a.post_mime_type IN ('image/jpeg', 'image/png', 'image/gif')
			";
		// $q = "SELECT count(*) FROM $wpdb->posts WHERE post_type = 'attachment' AND post_status = 'inherit' AND post_mime_type IN ('image/jpeg', 'image/png', 'image/gif') ";
		$groups_not_gathered = $groups_raw = $groups_all = $wpdb->get_var( $q );
		$imgs_raw = 0;
		$imgs_gathered = 0;

		if ( $tb_existed ) {
			$q = "SELECT COUNT(*)
				FROM `$wpdb->posts` a
				LEFT JOIN `$wpdb->postmeta` b ON b.post_id = a.ID AND b.meta_key = '_wp_attachment_metadata'
				LEFT JOIN `$this->_table_img_optm` c ON c.post_id = a.ID
				WHERE a.post_type = 'attachment'
					AND a.post_status = 'inherit'
					AND a.post_mime_type IN ('image/jpeg', 'image/png', 'image/gif')
					AND c.id IS NULL
				";
			$groups_not_gathered = $wpdb->get_var( $q );

			$q = $wpdb->prepare( "SELECT COUNT(DISTINCT post_id),COUNT(*) FROM `$this->_table_img_optm` WHERE optm_status = %d", self::STATUS_RAW );
			list( $groups_raw, $imgs_raw ) = $wpdb->get_row( $q, ARRAY_N );
			$imgs_gathered = $wpdb->get_var( "SELECT COUNT(*) FROM `$this->_table_img_optm`" );
		}

		$count_list = array(
			'groups_all'	=> $groups_all,
			'groups_not_gathered'	=> $groups_not_gathered,
			'group.' . self::STATUS_RAW	=> $groups_raw,
			'img.' . self::STATUS_RAW	=> $imgs_raw,
			'imgs_gathered'	=> $imgs_gathered,
		);

		// images count from work table
		if ( $tb_existed2 ) {
			$q = "SELECT COUNT(DISTINCT post_id),COUNT(*) FROM `$this->_table_img_optming` WHERE optm_status = %d";
			$groups_to_check = array(
				self::STATUS_REQUESTED,
				self::STATUS_NOTIFIED,
				self::STATUS_ERR_FETCH,
			);
			foreach ( $groups_to_check as $v ) {
				$count_list[ 'img.' . $v ] = $count_list[ 'group.' . $v ] = 0;
				if ( $tb_existed ) {
					list( $count_list[ 'group.' . $v ], $count_list[ 'img.' . $v ] ) = $wpdb->get_row( $wpdb->prepare( $q, $v ), ARRAY_N );
				}
			}
		}

		// images count from image table
		if ( $tb_existed ) {
			$q = "SELECT COUNT(DISTINCT post_id),COUNT(*) FROM `$this->_table_img_optm` WHERE optm_status = %d";
			$groups_to_check = array(
				self::STATUS_DUPLICATED,
				self::STATUS_PULLED,
				self::STATUS_FAILED,
				self::STATUS_MISS,
				self::STATUS_ERR_OPTM,
				self::STATUS_XMETA,
				self::STATUS_ERR,
			);
			foreach ( $groups_to_check as $v ) {
				$count_list[ 'img.' . $v ] = $count_list[ 'group.' . $v ] = 0;
				if ( $tb_existed ) {
					list( $count_list[ 'group.' . $v ], $count_list[ 'img.' . $v ] ) = $wpdb->get_row( $wpdb->prepare( $q, $v ), ARRAY_N );
				}
			}
		}

		return $count_list;
	}

	/**
	 * Check if fetch cron is running
	 *
	 * @since  1.6.2
	 * @access public
	 */
	public function cron_running( $bool_res = true )
	{
		$last_run = ! empty( $this->_summary[ 'last_pull' ] ) ? $this->_summary[ 'last_pull' ] : 0;

		$is_running = $last_run && time() - $last_run < 120;

		if ( $bool_res ) {
			return $is_running ;
		}

		return array( $last_run, $is_running ) ;
	}

	/**
	 * Update fetch cron timestamp tag
	 *
	 * @since  1.6.2
	 * @access private
	 */
	private function _update_cron_running( $done = false )
	{
		$this->_summary[ 'last_pull' ] = time();

		if ( $done ) {
			// Only update cron tag when its from the active running cron
			if ( $this->_cron_ran ) {
				// Rollback for next running
				$this->_summary[ 'last_pull' ] -= 120;
			}
			else {
				return;
			}
		}

		self::save_summary();

		$this->_cron_ran = true;
	}

	/**
	 * Batch switch images to ori/optm version
	 *
	 * @since  1.6.2
	 * @access private
	 */
	private function _batch_switch( $type )
	{
		global $wpdb;

		$offset = ! empty( $_GET[ 'litespeed_i' ] ) ? $_GET[ 'litespeed_i' ] : 0;
		$limit = 500;

		$q = "SELECT src,post_id FROM `$this->_table_img_optm` WHERE optm_status = %d ORDER BY id LIMIT %d, %d";
		$list = $wpdb->get_results( $wpdb->prepare( $q, array( self::STATUS_PULLED, $offset * $limit, $limit ) ) );

		$i = 0;
		foreach ( $list as $v ) {
			$extension = pathinfo( $v->src, PATHINFO_EXTENSION );
			$local_filename = substr( $v->src, 0, - strlen( $extension ) - 1 );
			$bk_file = $local_filename . '.bk.' . $extension;
			$bk_optm_file = $local_filename . '.bk.optm.' . $extension;

			// switch to ori
			if ( $type === self::TYPE_BATCH_SWITCH_ORI ) {
				if ( ! $this->__media->info( $bk_file, $v->post_id ) ) {
					continue;
				}

				$i ++;

				$this->__media->rename( $v->src, $bk_optm_file, $v->post_id );
				$this->__media->rename( $bk_file, $v->src, $v->post_id );
			}
			// switch to optm
			elseif ( $type === self::TYPE_BATCH_SWITCH_OPTM ) {
				if ( ! $this->__media->info( $bk_optm_file, $v->post_id ) ) {
					continue;
				}

				$i ++;

				$this->__media->rename( $v->src, $bk_file, $v->post_id );
				$this->__media->rename( $bk_optm_file, $v->src, $v->post_id );
			}
		}

		Debug2::debug( '[Img_Optm] batch switched images total: ' . $i );

		$offset ++;
		$q = "SELECT src,post_id FROM `$this->_table_img_optm` WHERE optm_status = %d ORDER BY id LIMIT %d, %d";
		$to_be_continued = $wpdb->get_row( $wpdb->prepare( $q, array( self::STATUS_PULLED, $offset * $limit, 1 ) ) );

		if ( $to_be_continued ) {
			return Router::self_redirect( Router::ACTION_IMG_OPTM, $type );
		}

		$msg = __( 'Switched images successfully.', 'litespeed-cache' );
		Admin_Display::succeed( $msg );
	}

	/**
	 * Switch image between original one and optimized one
	 *
	 * @since 1.6.2
	 * @access private
	 */
	private function _switch_optm_file( $type ) {
		global $wpdb;

		$pid = substr( $type, 4 );
		$switch_type = substr( $type, 0, 4 );

		$q = "SELECT src,post_id FROM `$this->_table_img_optm` WHERE post_id = %d AND optm_status = %d";
		$list = $wpdb->get_results( $wpdb->prepare( $q, array( $pid, self::STATUS_PULLED ) ) );

		$msg = 'Unknown Msg';

		foreach ( $list as $v ) {
			// to switch webp file
			if ( $switch_type === 'webp' ) {
				if ( $this->__media->info( $v->src . '.webp', $v->post_id ) ) {
					$this->__media->rename( $v->src . '.webp', $v->src . '.optm.webp', $v->post_id );
					Debug2::debug( '[Img_Optm] Disabled WebP: ' . $v->src );

					$msg = __( 'Disabled WebP file successfully.', 'litespeed-cache' );
				}
				elseif ( $this->__media->info( $v->src . '.optm.webp', $v->post_id ) ) {
					$this->__media->rename( $v->src . '.optm.webp', $v->src . '.webp', $v->post_id );
					Debug2::debug( '[Img_Optm] Enable WebP: ' . $v->src );

					$msg = __( 'Enabled WebP file successfully.', 'litespeed-cache' );
				}
			}
			// to switch original file
			else {
				$extension = pathinfo( $v->src, PATHINFO_EXTENSION );
				$local_filename = substr( $v->src, 0, - strlen( $extension ) - 1 );
				$bk_file = $local_filename . '.bk.' . $extension;
				$bk_optm_file = $local_filename . '.bk.optm.' . $extension;

				// revert ori back
				if ( $this->__media->info( $bk_file, $v->post_id ) ) {
					$this->__media->rename( $v->src, $bk_optm_file, $v->post_id );
					$this->__media->rename( $bk_file, $v->src, $v->post_id );
					Debug2::debug( '[Img_Optm] Restore original img: ' . $bk_file );

					$msg = __( 'Restored original file successfully.', 'litespeed-cache' );
				}
				elseif ( $this->__media->info( $bk_optm_file, $v->post_id ) ) {
					$this->__media->rename( $v->src, $bk_file, $v->post_id );
					$this->__media->rename( $bk_optm_file, $v->src, $v->post_id );
					Debug2::debug( '[Img_Optm] Switch to optm img: ' . $v->src );

					$msg = __( 'Switched to optimized file successfully.', 'litespeed-cache' );
				}

			}
		}

		Admin_Display::succeed( $msg );
	}

	/**
	 * Delete one optm data and recover original file
	 *
	 * @since 2.4.2
	 * @access public
	 */
	public function reset_row( $post_id )
	{
		global $wpdb;

		if ( ! $post_id ) {
			return;
		}

		// Gathered image don't have DB_SIZE info yet
		// $size_meta = get_post_meta( $post_id, self::DB_SIZE, true );

		// if ( ! $size_meta ) {
		// 	return;
		// }

		Debug2::debug( '[Img_Optm] _reset_row [pid] ' . $post_id );

		$q = "SELECT src,post_id FROM `$this->_table_img_optm` WHERE post_id = %d";
		$list = $wpdb->get_results( $wpdb->prepare( $q, $post_id ) );
		if ( ! $list ) {
			return;
		}

		foreach ( $list as $v ) {
			$this->__media->info( $v->src . '.webp', $v->post_id ) && $this->__media->del( $v->src . '.webp', $v->post_id );
			$this->__media->info( $v->src . '.optm.webp', $v->post_id ) && $this->__media->del( $v->src . '.optm.webp', $v->post_id );

			$extension = pathinfo( $v->src, PATHINFO_EXTENSION );
			$local_filename = substr( $v->src, 0, - strlen( $extension ) - 1 );
			$bk_file = $local_filename . '.bk.' . $extension;
			$bk_optm_file = $local_filename . '.bk.optm.' . $extension;

			if ( $this->__media->info( $bk_file, $v->post_id ) ) {
				Debug2::debug( '[Img_Optm] _reset_row Revert ori file' . $bk_file );
				$this->__media->del( $v->src, $v->post_id );
				$this->__media->rename( $bk_file, $v->src, $v->post_id );
			}
			elseif ( $this->__media->info( $bk_optm_file, $v->post_id ) ) {
				Debug2::debug( '[Img_Optm] _reset_row Del ori bk file' . $bk_optm_file );
				$this->__media->del( $bk_optm_file, $v->post_id );
			}
		}

		$q = "DELETE FROM `$this->_table_img_optm` WHERE post_id = %d";
		$wpdb->query( $wpdb->prepare( $q, $post_id ) );

		delete_post_meta( $post_id, self::DB_SIZE );

		$msg = __( 'Reset the optimized data successfully.', 'litespeed-cache' );
		Admin_Display::succeed( $msg );
	}

	/**
	 * Show an image's optm status
	 *
	 * @since  1.6.5
	 * @access public
	 */
	public function check_img() {
		global $wpdb;

		$pid = $_POST[ 'data' ] ;

		Debug2::debug( '[Img_Optm] Check image [ID] ' . $pid ) ;

		$data = array() ;

		$data[ 'img_count' ] = $this->img_count() ;
		$data[ 'optm_summary' ] = self::get_summary() ;

		$data[ '_wp_attached_file' ] = get_post_meta( $pid, '_wp_attached_file', true ) ;
		$data[ '_wp_attachment_metadata' ] = get_post_meta( $pid, '_wp_attachment_metadata', true ) ;

		// Get img_optm data
		$q = "SELECT * FROM `$this->_table_img_optm` WHERE post_id = %d" ;
		$list = $wpdb->get_results( $wpdb->prepare( $q, $pid ) ) ;
		$img_data = array() ;
		if ( $list ) {
			foreach ( $list as $v ) {
				$img_data[] = array(
					'id'	=> $v->id,
					'optm_status'	=> $v->optm_status,
					'src'	=> $v->src,
					'srcpath_md5'	=> $v->srcpath_md5,
					'src_md5'	=> $v->src_md5,
					'server_info'	=> $v->server_info,
				) ;
			}
		}
		$data[ 'img_data' ] = $img_data ;

		return array( '_res' => 'ok', 'data' => $data ) ;
	}

	/**
	 * Handle all request actions from main cls
	 *
	 * @since  2.0
	 * @access public
	 */
	public function handler() {
		$type = Router::verify_type();

		switch ( $type ) {
			case self::TYPE_RESET_ROW:
				$this->reset_row( ! empty( $_GET[ 'id' ] ) ? $_GET[ 'id' ] : false );
				break;

			case self::TYPE_CALC_BKUP:
				$this->_calc_bkup();
				break;

			case self::TYPE_RM_BKUP :
				$this->rm_bkup();
				break;

			case self::TYPE_NEW_REQ:
				$this->new_req();
				break;

			case self::TYPE_RESCAN:
				$this->_rescan();
				break;

			case self::TYPE_DESTROY:
				$this->_destroy();
				break;

			case self::TYPE_CLEAN:
				$this->clean();
				break;

			case self::TYPE_PULL:
				$this->pull();
				break;

			/**
			 * Batch switch
			 * @since 1.6.3
			 */
			case self::TYPE_BATCH_SWITCH_ORI:
			case self::TYPE_BATCH_SWITCH_OPTM:
				$this->_batch_switch( $type );
				break;

			case substr( $type, 0, 4 ) === 'webp':
			case substr( $type, 0, 4 ) === 'orig':
				$this->_switch_optm_file( $type );
				break;

			default:
				break;
		}

		Admin::redirect();
	}

}
