<?php
/**
* Lazy Load.
*
* @package Cloudinary
*/
namespace Cloudinary\Delivery;
use Cloudinary\Connect\Api;
use Cloudinary\Delivery_Feature;
use Cloudinary\Plugin;
use Cloudinary\String_Replace;
use Cloudinary\UI\Component\HTML;
use Cloudinary\Utils;
/**
* Class Responsive_Breakpoints
*
* @package Cloudinary
*/
class Lazy_Load extends Delivery_Feature {
/**
* Holds the settings slug.
*
* @var string
*/
protected $settings_slug = 'media_display';
/**
* Holds the enabler slug.
*
* @var string
*/
protected $enable_slug = 'use_lazy_load';
/**
* Lazy_Load constructor.
*
* @param \Cloudinary\Plugin $plugin The main instance of the plugin.
*/
public function __construct( Plugin $plugin ) {
parent::__construct( $plugin );
add_filter( 'cloudinary_image_tag-disabled', array( $this, 'js_noscript' ), 10, 2 );
}
/**
* Setup hooks.
*/
public function setup_hooks() {
add_action( 'wp', array( $this, 'init_lazy_script_maybe' ) );
add_filter( 'cloudinary_lazy_load_bypass', array( $this, 'bypass_lazy_load' ), 10, 2 );
}
/**
* Check if the page request is a dynamic lazy load request.
*/
public function init_lazy_script_maybe() {
$flag = Utils::get_sanitized_text( 'cloudinary_lazy_load_loader' );
if ( $flag ) {
$expires = HOUR_IN_SECONDS;
header( 'Cache-Control: max-age=' . $expires );
cache_javascript_headers();
echo $this->get_inline_script(); // phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped
exit;
}
}
/**
* Maybe bypass the lazy load.
*
* @param bool $bypass Whether to bypass lazy load.
* @param array $tag_element The TAG element.
*
* @return bool
*/
public function bypass_lazy_load( $bypass, $tag_element ) {
// Bypass if eager loading.
if ( ! empty( $tag_element['loading'] ) && 'eager' === $tag_element['loading'] ) {
$bypass = true;
}
/**
* Filter the classes that bypass lazy loading.
*
* @hook cloudinary_lazy_load_bypass_classes
* @since 3.0.9
*
* @param $classes {array} Classes that bypass the Lazy Load.
*
* @return {bool}
*
* @example
* <?php
*
* // Extend bypass lazy load classes to include `skip-lazy`.
* add_filter(
* 'cloudinary_lazy_load_bypass_classes',
* function( $classes ) {
* $classes[] = 'skip-lazy';
* return $classes;
* }
* );
*/
$bypass_classes = apply_filters( 'cloudinary_lazy_load_bypass_classes', array( 'cld-bypass-lazy' ) );
if ( ! $bypass && ! empty( array_intersect( $bypass_classes, $tag_element['atts']['class'] ) ) ) {
$bypass = true;
}
return $bypass;
}
/**
* Get the inline script for lazy load.
*
* @retrun string
*/
public function get_inline_script() {
$config = $this->get_config();
return 'var CLDLB = ' . wp_json_encode( $config ) . ';' . file_get_contents( $this->plugin->dir_path . 'js/inline-loader.js' );
}
/**
* Get the config for lazy load.
*
* @return array
*/
public function get_config() {
$config = $this->config; // Get top most config.
if ( 'off' !== $config['lazy_placeholder'] ) {
$config['placeholder'] = API::generate_transformation_string( $this->get_placeholder_transformations( $config['lazy_placeholder'] ) );
}
$config['base_url'] = $this->media->base_url;
return $config;
}
/**
* Wrap image tags in noscript to allow no-javascript browsers to get images.
*
* @param string $tag The original html tag.
* @param array $tag_element The original tag_element.
*
* @return string
*/
public function js_noscript( $tag, $tag_element ) {
$options = $tag_element['atts'];
$options['class'] = implode( ' ', $options['class'] );
unset(
$options['srcset'],
$options['sizes'],
$options['loading'],
$options['src'],
$options['class']
);
$atts = array(
'data-image' => wp_json_encode( $options ),
);
return HTML::build_tag( 'noscript', $atts ) . $tag . HTML::build_tag( 'noscript', null, 'close' );
}
/**
* Get the placeholder generation transformations.
*
* @param string $placeholder The placeholder to get.
*
* @return array
*/
public function get_placeholder_transformations( $placeholder ) {
$transformations = array(
'predominant' => array(
array(
'$currWidth' => 'w',
'$currHeight' => 'h',
),
array(
'width' => 'iw_div_2',
'aspect_ratio' => 1,
'crop' => 'pad',
'background' => 'auto',
),
array(
'crop' => 'crop',
'width' => 10,
'height' => 10,
'gravity' => 'north_east',
),
array(
'width' => '$currWidth',
'height' => '$currHeight',
'crop' => 'fill',
),
array(
'fetch_format' => 'auto',
'quality' => 'auto',
),
),
'vectorize' => array(
array(
'effect' => 'vectorize:3:0.1',
'fetch_format' => 'svg',
),
),
'blur' => array(
array(
'effect' => 'blur:2000',
'quality' => 1,
'fetch_format' => 'auto',
),
),
'pixelate' => array(
array(
'effect' => 'pixelate',
'quality' => 1,
'fetch_format' => 'auto',
),
),
);
return $transformations[ $placeholder ];
}
/**
* Add features to a tag element set.
*
* @param array $tag_element The tag element set.
*
* @return array
*/
public function add_features( $tag_element ) {
if ( Utils::is_amp() ) {
return $tag_element;
}
static $has_loader = false;
// Bypass file formats that shouldn't be lazy loaded.
if (
in_array(
$tag_element['format'],
/**
* Filter out file formats for Lazy Load.
*
* @hook cloudinary_lazy_load_bypass_formats
* @since 3.0.0
*
* @param $formats {array) The list of formats to exclude.
*
* @return {array}
*/
apply_filters( 'cloudinary_lazy_load_bypass_formats', array( 'svg' ) ),
true
)
) {
return $tag_element;
}
/**
* Short circuit the lazy load.
*
* @hook cloudinary_lazy_load_bypass
*
* @since 3.0.9
*
* @param $short_circuit {bool} The short circuit value.
* @param $tag_element {array} The tag element.
*
* @return {bool}
*
* @example
* <?php
*
* // Bypass lazy load for images with ID `feature-image`.
* add_filter(
* 'cloudinary_lazy_load_bypass',
* function( $bypass, $tag_element ) {
* if ( 'feature-image! === $tag_element['id'] ) {
* $bypass = true;
* }
* return $bypass;
* }
* );
*/
if ( apply_filters( 'cloudinary_lazy_load_bypass', false, $tag_element ) ) {
return $tag_element;
}
$sizes = array(
$tag_element['width'],
$tag_element['height'],
);
// Capture the original size.
$tag_element['atts']['data-size'] = array_filter( $sizes );
$colors = $this->config['lazy_custom_color'];
$animation = array(
$colors,
);
if ( 'on' === $this->config['lazy_animate'] ) {
preg_match_all( '/(\d\.*)+/', $colors, $matched );
$fade = $matched[0];
$fade[3] = 0.1;
$fade = 'rgba(' . implode( ',', $fade ) . ')';
$animation[] = $fade;
$animation[] = $colors;
}
$colors = implode( ';', $animation );
// Add svg placeholder.
$tag_element['atts']['src'] = Utils::svg_encoded( $tag_element['atts']['width'], $tag_element['atts']['height'], $colors );
if ( isset( $tag_element['atts']['srcset'] ) ) {
$tag_element['atts']['data-srcset'] = $tag_element['atts']['srcset'];
$tag_element['atts']['data-sizes'] = $tag_element['atts']['sizes'];
unset( $tag_element['atts']['srcset'], $tag_element['atts']['sizes'] );
}
if ( ! Utils::is_admin() ) {
$tag_element['atts']['data-delivery'] = $this->media->get_media_delivery( $tag_element['id'] );
if ( empty( $tag_element['atts']['onload'] ) ) {
$tag_element['atts']['onload'] = '';
}
$loader = 'null;';
if ( ! $has_loader && Utils::is_frontend_ajax() ) {
$has_loader = true;
$url = add_query_arg( 'cloudinary_lazy_load_loader', true, trailingslashit( home_url() ) );
$loader = 'document.body.appendChild(document.createElement(\'script\')).src=\'' . $url . '\';this.onload=null;';
}
// Since we're appending to the onload, check it isn't already in, as it may run twice i.e full page caching.
if ( false === strpos( $tag_element['atts']['onload'], 'CLDBind' ) ) {
$tag_element['atts']['data-cloudinary'] = 'lazy';
$tag_element['atts']['onload'] .= ';window.CLDBind?CLDBind(this):' . $loader;
}
}
return $tag_element;
}
/**
* Register front end hooks.
*/
public function register_assets() {
wp_register_script( 'cld-lazy-load', $this->plugin->dir_url . 'js/lazy-load.js', null, $this->plugin->version, false );
}
/**
* Apply front end filters on the enqueue_assets hook.
*/
public function enqueue_assets() {
if ( Utils::is_frontend_ajax() ) {
return;
}
ob_start();
Utils::print_inline_tag( $this->get_inline_script() );
$script = ob_get_clean();
$script_holder = '<meta name="cld-loader">';
$allow = array(
'meta' => array(
'name' => true,
),
);
echo wp_kses( $script_holder, $allow );
String_Replace::replace( $script_holder, $script );
}
/**
* Enqueue assets if not AMP.
*/
public function maybe_enqueue_assets() {
if ( ! Utils::is_amp() ) {
parent::maybe_enqueue_assets();
}
}
/**
* Check if component is active.
*
* @return bool
*/
public function is_active() {
return ( ! Utils::is_admin() && ! Utils::is_rest_api() ) || Utils::is_frontend_ajax();
}
/**
* Add the settings.
*
* @param array $pages The pages to add to.
*
* @return array
*/
public function register_settings( $pages ) {
$pages['lazy_loading'] = array(
'page_title' => __( 'Lazy loading', 'cloudinary' ),
'menu_title' => __( 'Lazy loading', 'cloudinary' ),
'priority' => 5,
'requires_connection' => true,
'sidebar' => true,
'settings' => array(
array(
'type' => 'panel',
'title' => __( 'Lazy Loading', 'cloudinary' ),
'priority' => 9,
'option_name' => 'media_display',
array(
'type' => 'tabs',
'tabs' => array(
'image_setting' => array(
'text' => __( 'Settings', 'cloudinary' ),
'id' => 'settings',
),
'image_preview' => array(
'text' => __( 'Preview', 'cloudinary' ),
'id' => 'preview',
),
),
),
array(
'type' => 'row',
array(
'type' => 'column',
'tab_id' => 'settings',
array(
'type' => 'on_off',
'description' => __( 'Enable lazy loading', 'cloudinary' ),
'tooltip_text' => __( 'Lazy loading delays the initialization of your web assets to improve page load times.', 'cloudinary' ),
'optimisation_title' => __( 'Lazy loading', 'cloudinary' ),
'slug' => 'use_lazy_load',
'default' => 'on',
),
array(
'type' => 'group',
'condition' => array(
'use_lazy_load' => true,
),
array(
'type' => 'text',
'title' => __( 'Lazy loading threshold', 'cloudinary' ),
'tooltip_text' => __( 'How far down the page to start lazy loading assets.', 'cloudinary' ),
'slug' => 'lazy_threshold',
'attributes' => array(
'style' => array(
'width:100px;display:block;',
),
'data-auto-suffix' => '*px;em;rem;vh',
),
'default' => '100px',
),
array(
'type' => 'tag',
'element' => 'hr',
),
array(
'type' => 'color',
'title' => __( 'Pre-loader color', 'cloudinary' ),
'description' => __(
'On page load, the pre-loader is used to fill the space while the image is downloaded, preventing content shift.',
'cloudinary'
),
'slug' => 'lazy_custom_color',
'default' => 'rgba(153,153,153,0.5)',
),
array(
'type' => 'on_off',
'description' => __( 'Pre-loader animation', 'cloudinary' ),
'slug' => 'lazy_animate',
'default' => 'on',
),
array(
'type' => 'tag',
'element' => 'hr',
),
array(
'type' => 'radio',
'title' => __( 'Placeholder generation type', 'cloudinary' ),
'description' => __(
"Placeholders are low-res representations of the image, that's loaded below the fold. They are then replaced with the actual image, just before it comes into view.",
'cloudinary'
),
'slug' => 'lazy_placeholder',
'default' => 'blur',
'condition' => array(
'use_lazy_load' => true,
),
'options' => array(
'blur' => __( 'Blur', 'cloudinary' ),
'pixelate' => __( 'Pixelate', 'cloudinary' ),
'vectorize' => __( 'Vectorize', 'cloudinary' ),
'predominant' => __( 'Dominant Color', 'cloudinary' ),
'off' => __( 'Off', 'cloudinary' ),
),
),
array(
'type' => 'tag',
'element' => 'hr',
),
array(
'type' => 'select',
'slug' => 'dpr',
'priority' => 8,
'title' => __( 'DPR settings', 'cloudinary' ),
'tooltip_text' => __( 'The device pixel ratio to use for your generated images.', 'cloudinary' ),
'default' => '2X',
'options' => array(
'off' => __( 'Off', 'cloudinary' ),
'2X' => __( 'Auto (2x)', 'cloudinary' ),
'max' => __( 'Max DPR', 'cloudinary' ),
),
),
),
),
array(
'type' => 'column',
'tab_id' => 'preview',
'class' => array(
'cld-ui-preview',
),
'condition' => array(
'use_lazy_load' => true,
),
array(
'type' => 'lazyload_preview',
'title' => __( 'Preview', 'cloudinary' ),
'slug' => 'lazyload_preview',
'default' => CLOUDINARY_ENDPOINTS_PREVIEW_IMAGE . 'w_600/sample.jpg',
),
),
),
array(
'type' => 'info_box',
'icon' => $this->plugin->dir_url . 'css/images/academy-icon.svg',
'title' => __( 'Need help?', 'cloudinary' ),
'text' => sprintf(
// Translators: The HTML for opening and closing link tags.
__(
'Watch free lessons on how to use the Lazy Load Settings in the %1$sCloudinary Academy%2$s.',
'cloudinary'
),
'<a href="https://training.cloudinary.com/learn/course/introduction-to-cloudinary-for-wordpress-administrators-70-minute-course-1h85/lessons/lazily-loading-and-delivering-responsive-images-1003?page=1" target="_blank" rel="noopener noreferrer">',
'</a>'
),
),
),
),
);
return $pages;
}
}