%k25u25%fgd5n!
<?php
/**
* The Placeholder class.
*
* Handles responsive placeholders (LQIP), admin column rendering,
* queueing, and generation logic (local and cloud).
*
* @since 3.0
* @package LiteSpeed
*/
namespace LiteSpeed;
defined( 'WPINC' ) || exit();
/**
* Class Placeholder
*/
class Placeholder extends Base {
/**
* Action type: generate.
*
* @var string
*/
const TYPE_GENERATE = 'generate';
/**
* Action type: clear queue.
*
* @var string
*/
const TYPE_CLEAR_Q = 'clear_q';
/**
* Whether responsive placeholders are enabled.
*
* @var bool
*/
private $_conf_placeholder_resp;
/**
* SVG template for responsive placeholders.
*
* @var string
*/
private $_conf_placeholder_resp_svg;
/**
* Whether LQIP generation via cloud is enabled.
*
* @var bool
*/
private $_conf_lqip;
/**
* LQIP JPEG quality.
*
* @var int
*/
private $_conf_lqip_qual;
/**
* Minimum width for LQIP generation.
*
* @var int
*/
private $_conf_lqip_min_w;
/**
* Minimum height for LQIP generation.
*
* @var int
*/
private $_conf_lqip_min_h;
/**
* Background color for SVG placeholders.
*
* @var string
*/
private $_conf_placeholder_resp_color;
/**
* Whether LQIP generation is async (queued).
*
* @var bool
*/
private $_conf_placeholder_resp_async;
/**
* Default placeholder data (fallback).
*
* @var string
*/
private $_conf_ph_default;
/**
* In-memory map of generated placeholders for current request.
*
* @var array<string,string>
*/
private $_placeholder_resp_dict = [];
/**
* Keys currently queued within this request.
*
* @var array<int,string>
*/
private $_ph_queue = [];
/**
* Stats & request summary for throttling.
*
* @var array<string,mixed>
*/
protected $_summary;
/**
* Init
*
* @since 3.0
*/
public function __construct() {
$this->_conf_placeholder_resp = defined( 'LITESPEED_GUEST_OPTM' ) || $this->conf( self::O_MEDIA_PLACEHOLDER_RESP );
$this->_conf_placeholder_resp_svg = $this->conf( self::O_MEDIA_PLACEHOLDER_RESP_SVG );
$this->_conf_lqip = ! defined( 'LITESPEED_GUEST_OPTM' ) && $this->conf( self::O_MEDIA_LQIP );
$this->_conf_lqip_qual = $this->conf( self::O_MEDIA_LQIP_QUAL );
$this->_conf_lqip_min_w = $this->conf( self::O_MEDIA_LQIP_MIN_W );
$this->_conf_lqip_min_h = $this->conf( self::O_MEDIA_LQIP_MIN_H );
$this->_conf_placeholder_resp_async = $this->conf( self::O_MEDIA_PLACEHOLDER_RESP_ASYNC );
$this->_conf_placeholder_resp_color = $this->conf( self::O_MEDIA_PLACEHOLDER_RESP_COLOR );
$this->_conf_ph_default = $this->conf(self::O_MEDIA_LAZY_PLACEHOLDER) ? $this->conf(self::O_MEDIA_LAZY_PLACEHOLDER) : LITESPEED_PLACEHOLDER;
$this->_summary = self::get_summary();
}
/**
* Init Placeholder.
*/
public function init() {
Debug2::debug2( '[LQIP] init' );
add_action( 'litespeed_after_admin_init', [ $this, 'after_admin_init' ] );
}
/**
* Display column in Media.
*
* @since 3.0
* @access public
*/
public function after_admin_init() {
if ( $this->_conf_lqip ) {
add_filter( 'manage_media_columns', [ $this, 'media_row_title' ] );
add_filter( 'manage_media_custom_column', [ $this, 'media_row_actions' ], 10, 2 );
add_action( 'litespeed_media_row_lqip', [ $this, 'media_row_con' ] );
}
}
/**
* Media Admin Menu -> LQIP column header.
*
* @since 3.0
* @param array<string,string> $posts_columns Columns.
* @return array<string,string>
*/
public function media_row_title( $posts_columns ) {
$posts_columns['lqip'] = __( 'LQIP', 'litespeed-cache' );
return $posts_columns;
}
/**
* Media Admin Menu -> LQIP Column renderer trigger.
*
* @since 3.0
* @param string $column_name Column name.
* @param int $post_id Attachment ID.
* @return void
*/
public function media_row_actions( $column_name, $post_id ) {
if ( 'lqip' !== $column_name ) {
return;
}
do_action( 'litespeed_media_row_lqip', $post_id );
}
/**
* Display LQIP column.
*
* @since 3.0
* @param int $post_id Attachment ID.
* @return void
*/
public function media_row_con( $post_id ) {
$meta_value = wp_get_attachment_metadata( $post_id );
if ( empty( $meta_value['file'] ) ) {
return;
}
$total_files = 0;
// List all sizes.
$all_sizes = [ $meta_value['file'] ];
$size_path = pathinfo( $meta_value['file'], PATHINFO_DIRNAME ) . '/';
if ( ! empty( $meta_value['sizes'] ) && is_array( $meta_value['sizes'] ) ) {
foreach ( $meta_value['sizes'] as $v ) {
if ( ! empty( $v['file'] ) ) {
$all_sizes[] = $size_path . $v['file'];
}
}
}
foreach ( $all_sizes as $short_path ) {
$lqip_folder = LITESPEED_STATIC_DIR . '/lqip/' . $short_path;
if ( is_dir( $lqip_folder ) ) {
Debug2::debug( '[LQIP] Found folder: ' . $short_path );
// List all files.
foreach ( scandir( $lqip_folder ) as $v ) {
if ( '.' === $v || '..' === $v ) {
continue;
}
if ( 0 === $total_files ) {
echo '<div class="litespeed-media-lqip"><img src="' .
esc_url( Str::trim_quotes( File::read( $lqip_folder . '/' . $v ) ) ) .
'" alt="' .
esc_attr( sprintf( __( 'LQIP image preview for size %s', 'litespeed-cache' ), $v ) ) .
'"></div>';
}
echo '<div class="litespeed-media-size"><a href="' . esc_url( Str::trim_quotes( File::read( $lqip_folder . '/' . $v ) ) ) . '" target="_blank">' . esc_html( $v ) . '</a></div>';
++$total_files;
}
}
}
if ( 0 === $total_files ) {
echo '—';
}
}
/**
* Replace image HTML with placeholder-based lazy version.
*
* @since 3.0
* @param string $html Original <img> HTML.
* @param string $src Image source URL.
* @param string $size Requested size (e.g. "300x200").
* @return string Modified HTML.
*/
public function replace( $html, $src, $size ) {
// Check if need to enable responsive placeholder or not.
$ph_candidate = $this->_placeholder( $src, $size );
$this_placeholder = $ph_candidate ? $ph_candidate : $this->_conf_ph_default;
$additional_attr = '';
if ( $this->_conf_lqip && $this_placeholder !== $this->_conf_ph_default ) {
Debug2::debug2( '[LQIP] Use resp LQIP [size] ' . $size );
$additional_attr = ' data-placeholder-resp="' . esc_attr( Str::trim_quotes( $size ) ) . '"';
}
$snippet = ( defined( 'LITESPEED_GUEST_OPTM' ) || $this->conf( self::O_OPTM_NOSCRIPT_RM ) ) ? '' : '<noscript>' . $html . '</noscript>';
$html = preg_replace(
[
'/\s+src=/i',
'/\s+srcset=/i',
'/\s+sizes=/i',
],
[
' data-src=',
' data-srcset=',
' data-sizes=',
],
$html
);
$html = preg_replace(
'/<img\s+/i',
'<img data-lazyloaded="1"' . $additional_attr . ' src="' . Str::trim_quotes($this_placeholder) . '" ',
$html
);
// $html = str_replace( array( ' src=', ' srcset=', ' sizes=' ), array( ' data-src=', ' data-srcset=', ' data-sizes=' ), $html );
// $html = str_replace( '<img ', '<img data-lazyloaded="1"' . $additional_attr . ' src="' . esc_url( Str::trim_quotes( $this_placeholder ) ) . '" ', $html );
$snippet = $html . $snippet;
return $snippet;
}
/**
* Generate responsive placeholder (or schedule generation).
*
* @since 2.5.1
* @access private
* @param string $src Image source URL.
* @param string $size Size string "WIDTHxHEIGHT".
* @return string|false Data URL placeholder or false.
*/
private function _placeholder( $src, $size ) {
// Low Quality Image Placeholders.
if ( ! $size ) {
Debug2::debug2( '[LQIP] no size ' . $src );
return false;
}
if ( ! $this->_conf_placeholder_resp ) {
return false;
}
// If use local generator.
if ( ! $this->_conf_lqip || ! $this->_lqip_size_check( $size ) ) {
return $this->_generate_placeholder_locally( $size );
}
Debug2::debug2( '[LQIP] Resp LQIP process [src] ' . $src . ' [size] ' . $size );
$arr_key = $size . ' ' . $src;
// Check if its already in dict or not.
if ( ! empty( $this->_placeholder_resp_dict[ $arr_key ] ) ) {
Debug2::debug2( '[LQIP] already in dict' );
return $this->_placeholder_resp_dict[ $arr_key ];
}
// Need to generate the responsive placeholder.
$placeholder_realpath = $this->_placeholder_realpath( $src, $size ); // todo: give offload API.
if ( file_exists( $placeholder_realpath ) ) {
Debug2::debug2( '[LQIP] file exists' );
$this->_placeholder_resp_dict[ $arr_key ] = File::read( $placeholder_realpath );
return $this->_placeholder_resp_dict[ $arr_key ];
}
// Prevent repeated requests in same request.
if ( in_array( $arr_key, $this->_ph_queue, true ) ) {
Debug2::debug2( '[LQIP] file bypass generating due to in queue' );
return $this->_generate_placeholder_locally( $size );
}
$hit = Utility::str_hit_array( $src, $this->conf( self::O_MEDIA_LQIP_EXC ) );
if ( $hit ) {
Debug2::debug2( '[LQIP] file bypass generating due to exclude setting [hit] ' . $hit );
return $this->_generate_placeholder_locally( $size );
}
$this->_ph_queue[] = $arr_key;
// Send request to generate placeholder.
if ( ! $this->_conf_placeholder_resp_async ) {
// If requested recently, bypass.
if ( $this->_summary && ! empty( $this->_summary['curr_request'] ) && ( time() - (int) $this->_summary['curr_request'] ) < 300 ) {
Debug2::debug2( '[LQIP] file bypass generating due to interval limit' );
return false;
}
// Generate immediately.
$this->_placeholder_resp_dict[ $arr_key ] = $this->_generate_placeholder( $arr_key );
return $this->_placeholder_resp_dict[ $arr_key ];
}
// Prepare default svg placeholder as tmp placeholder.
$tmp_placeholder = $this->_generate_placeholder_locally( $size );
// Store it to prepare for cron.
$queue = $this->load_queue( 'lqip' );
if ( in_array( $arr_key, $queue, true ) ) {
Debug2::debug2( '[LQIP] already in queue' );
return $tmp_placeholder;
}
if ( count( $queue ) > 500 ) {
Debug2::debug2( '[LQIP] queue is full' );
return $tmp_placeholder;
}
$queue[] = $arr_key;
$this->save_queue( 'lqip', $queue );
Debug2::debug( '[LQIP] Added placeholder queue' );
return $tmp_placeholder;
}
/**
* Generate realpath of placeholder file.
*
* @since 2.5.1
* @access private
* @param string $src Image source URL.
* @param string $size Size string "WIDTHxHEIGHT".
* @return string Absolute file path.
*/
private function _placeholder_realpath( $src, $size ) {
// Use LQIP Cloud generator, each image placeholder will be separately stored.
// Compatibility with WebP and AVIF.
$src = Utility::drop_webp( $src );
$filepath_prefix = $this->_build_filepath_prefix( 'lqip' );
// External images will use cache folder directly.
$domain = wp_parse_url( $src, PHP_URL_HOST );
if ( $domain && ! Utility::internal( $domain ) ) {
// todo: need to improve `util:internal()` to include `CDN::internal()`
$md5 = md5($src);
return LITESPEED_STATIC_DIR . $filepath_prefix . 'remote/' . substr( $md5, 0, 1 ) . '/' . substr( $md5, 1, 1 ) . '/' . $md5 . '.' . $size;
}
// Drop domain.
$short_path = Utility::att_short_path( $src );
return LITESPEED_STATIC_DIR . $filepath_prefix . $short_path . '/' . $size;
}
/**
* Cron placeholder generation.
*
* @since 2.5.1
* @param bool $do_continue If true, process full queue in one run.
* @return void
*/
public static function cron( $do_continue = false ) {
$_instance = self::cls();
$queue = $_instance->load_queue( 'lqip' );
if ( empty( $queue ) ) {
return;
}
// For cron, need to check request interval too.
if ( ! $do_continue ) {
if ( ! empty( $_instance->_summary['curr_request'] ) && ( time() - (int) $_instance->_summary['curr_request'] ) < 300 ) {
Debug2::debug( '[LQIP] Last request not done' );
return;
}
}
foreach ( $queue as $v ) {
Debug2::debug( '[LQIP] cron job [size] ' . $v );
$res = $_instance->_generate_placeholder( $v, true );
// Exit queue if out of quota.
if ( 'out_of_quota' === $res ) {
return;
}
// Only request first one unless continuing.
if ( ! $do_continue ) {
return;
}
}
}
/**
* Generate placeholder locally (SVG).
*
* @since 3.0
* @access private
* @param string $size Size string "WIDTHxHEIGHT".
* @return string Data URL for SVG placeholder.
*/
private function _generate_placeholder_locally( $size ) {
Debug2::debug2( '[LQIP] _generate_placeholder local [size] ' . $size );
$size = explode( 'x', $size );
$svg = str_replace(
[ '{width}', '{height}', '{color}' ],
[ (int) $size[0], (int) $size[1], $this->_conf_placeholder_resp_color ],
$this->_conf_placeholder_resp_svg
);
// phpcs:ignore WordPress.PHP.DiscouragedPHPFunctions.obfuscation_base64_encode
return 'data:image/svg+xml;base64,' . base64_encode( $svg );
}
/**
* Send to LiteSpeed API to generate placeholder (and persist).
*
* @since 2.5.1
* @access private
* @param string $raw_size_and_src Concatenated "SIZE SRC".
* @param bool $from_cron If true, called from cron context.
* @return string Data URL placeholder.
*/
private function _generate_placeholder( $raw_size_and_src, $from_cron = false ) {
// Parse containing size and src info.
$size_and_src = explode( ' ', $raw_size_and_src, 2 );
$size = $size_and_src[0];
if ( empty( $size_and_src[1] ) ) {
$this->_popup_and_save( $raw_size_and_src );
Debug2::debug( '[LQIP] ❌ No src [raw] ' . $raw_size_and_src );
return $this->_generate_placeholder_locally( $size );
}
$src = $size_and_src[1];
$file = $this->_placeholder_realpath( $src, $size );
// Local generate SVG to serve (repeated here to clear queue if settings changed).
if ( ! $this->_conf_lqip || ! $this->_lqip_size_check( $size ) ) {
$data = $this->_generate_placeholder_locally( $size );
} else {
$err = false;
$allowance = Cloud::cls()->allowance( Cloud::SVC_LQIP, $err );
if ( ! $allowance ) {
Debug2::debug( '[LQIP] ❌ No credit: ' . $err );
$err && Admin_Display::error( Error::msg( $err ) );
if ( $from_cron ) {
return 'out_of_quota';
}
return $this->_generate_placeholder_locally( $size );
}
// Generate LQIP.
list( $width, $height ) = explode( 'x', $size );
$req_data = [
'width' => (int) $width,
'height' => (int) $height,
'url' => Utility::drop_webp( $src ),
'quality' => (int) $this->_conf_lqip_qual,
];
// Check if the image is 404 first.
if ( File::is_404( $req_data['url'] ) ) {
$this->_popup_and_save( $raw_size_and_src, true );
$this->_append_exc( $src );
Debug2::debug( '[LQIP] 404 before request [src] ' . $req_data['url'] );
return $this->_generate_placeholder_locally( $size );
}
// Update request status.
$this->_summary['curr_request'] = time();
self::save_summary();
$json = Cloud::post( Cloud::SVC_LQIP, $req_data, 120 );
if ( ! is_array( $json ) ) {
return $this->_generate_placeholder_locally( $size );
}
if ( empty( $json['lqip'] ) || 0 !== strpos( $json['lqip'], 'data:image/svg+xml' ) ) {
// Image error, pop up the current queue.
$this->_popup_and_save( $raw_size_and_src, true );
$this->_append_exc( $src );
Debug2::debug( '[LQIP] wrong response format', $json );
return $this->_generate_placeholder_locally( $size );
}
$data = $json['lqip'];
Debug2::debug( '[LQIP] _generate_placeholder LQIP' );
}
// Write to file.
File::save( $file, $data, true );
// Save summary data.
$this->_summary['last_spent'] = time() - (int) $this->_summary['curr_request'];
$this->_summary['last_request'] = $this->_summary['curr_request'];
$this->_summary['curr_request'] = 0;
self::save_summary();
$this->_popup_and_save( $raw_size_and_src );
Debug2::debug( '[LQIP] saved LQIP ' . $file );
return $data;
}
/**
* Check if the size is valid to send LQIP request or not.
*
* @since 3.0
* @param string $size Size string "WIDTHxHEIGHT".
* @return bool True if meets minimums.
*/
private function _lqip_size_check( $size ) {
$size = explode( 'x', $size );
if ( ( (int) $size[0] >= (int) $this->_conf_lqip_min_w ) || ( (int) $size[1] >= (int) $this->_conf_lqip_min_h ) ) {
return true;
}
Debug2::debug2( '[LQIP] Size too small' );
return false;
}
/**
* Add to LQIP exclude list.
*
* @since 3.4
* @param string $src Image URL.
* @return void
*/
private function _append_exc( $src ) {
$val = $this->conf( self::O_MEDIA_LQIP_EXC );
$val[] = $src;
$this->cls( 'Conf' )->update( self::O_MEDIA_LQIP_EXC, $val );
Debug2::debug( '[LQIP] Appended to LQIP Excludes [URL] ' . $src );
}
/**
* Pop up the current request from queue and save.
*
* @since 3.0
* @param string $raw_size_and_src Concatenated "SIZE SRC".
* @param bool $append_to_exc If true, also add to exclusion list.
* @return void
*/
private function _popup_and_save( $raw_size_and_src, $append_to_exc = false ) {
$queue = $this->load_queue( 'lqip' );
if ( ! empty( $queue ) && in_array( $raw_size_and_src, $queue, true ) ) {
$idx = array_search( $raw_size_and_src, $queue, true );
if ( false !== $idx ) {
unset( $queue[ $idx ] );
}
}
if ( $append_to_exc ) {
$size_and_src = explode( ' ', $raw_size_and_src, 2 );
if (isset( $size_and_src[1] ) && $size_and_src[1]) {
$this_src = $size_and_src[1];
// Append to lqip exc setting first.
$this->_append_exc( $this_src );
// Check if other queues contain this src or not.
if ( $queue ) {
foreach ( $queue as $k => $raw_item ) {
$parsed = explode( ' ', $raw_item, 2 );
if ( empty( $parsed[1] ) ) {
continue;
}
if ( $parsed[1] === $this_src ) {
unset( $queue[ $k ] );
}
}
}
}
}
$this->save_queue( 'lqip', $queue );
}
/**
* Handle all request actions from main cls.
*
* @since 2.5.1
* @access public
* @return void
*/
public function handler() {
$type = Router::verify_type();
switch ( $type ) {
case self::TYPE_GENERATE:
self::cron( true );
break;
case self::TYPE_CLEAR_Q:
$this->clear_q( 'lqip' );
break;
default:
break;
}
Admin::redirect();
}
}