<?php
/**
 * Class Advanced
 *
 * Implements various advanced features of the plugin: removing query strings from static resources,
 * removing the emojis file from rendering on the pages, prefetching dns queries.
 *
 * @since 1.8
 * @package Hummingbird\Core\Modules
 */

namespace Hummingbird\Core\Modules;

use Hummingbird\Core\Module;
use Hummingbird\Core\Settings;
use Hummingbird\Core\Utils;
use Hummingbird\Core\Traits\Module as ModuleContract;
use stdClass;

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

/**
 * Class Advanced
 */
class Advanced extends Module {

	use ModuleContract;

	/**
	 * Font awesome domain.
	 *
	 * @since 3.8.0
	 * @var string $font_awesome_domain
	 */
	private $font_awesome_domain = 'use.fontawesome.com';

	/**
	 * Google font domain.
	 *
	 * @since 3.8.0
	 * @var string $google_font_domain
	 */
	private $google_font_domain = 'fonts.googleapis.com';

	/**
	 * Initializes the module. Always executed even if the module is deactivated.
	 *
	 * Do not use __construct in subclasses, use init() instead
	 */
	public function init() {
		$options = $this->get_options();

		// See if we need to fetch the network value for query strings option.
		if ( ( $options['query_strings_global'] || $options['emoji_global'] ) && is_multisite() ) {
			$network_options = get_blog_option( get_main_site_id(), 'wphb_settings' );

			if ( $options['query_strings_global'] && isset( $network_options['advanced'] ) && isset( $network_options['advanced']['query_string'] ) ) {
				$options['query_string'] = $network_options['advanced']['query_string'];
			}
			if ( $options['emoji_global'] && isset( $network_options['advanced'] ) && isset( $network_options['advanced']['emoji'] ) ) {
				$options['emoji'] = $network_options['advanced']['emoji'];
			}
		}

		// Remove emoji.
		if ( $options['emoji'] ) {
			// Remove styles/scripts.
			$this->remove_emoji();
			// Remove dns prefetch.
			add_filter( 'emoji_svg_url', '__return_false' );
			// Remove from TinyMCE.
			add_filter( 'tiny_mce_plugins', array( $this, 'remove_emoji_tinymce' ) );
		}

		// Process HB cleanup task.
		add_action( 'wphb_hummingbird_cleanup', array( $this, 'hb_cleanup_cron' ) );

		// Ajax handler to return the comment template.
		add_action( 'wp_ajax_get_comments_template', array( $this, 'comment_template' ) );
		add_action( 'wp_ajax_nopriv_get_comments_template', array( $this, 'comment_template' ) );

		if ( isset( $options['lazy_load'] ) && $options['lazy_load']['enabled'] ) {
			/* Divi Compatibility  */
			add_filter( 'et_builder_load_requests', array( $this, 'add_divi_support' ) );
			add_action( 'wp_enqueue_scripts', array( $this, 'enqueue_global' ) );
		}
		add_filter( 'paginate_links', array( $this, 'strip_params' ) );

		// Everything else is only for frontend.
		if ( is_admin() ) {
			return;
		}

		// Disable WooCommerce cart fragments.
		add_action( 'wp_enqueue_scripts', array( $this, 'remove_cart_fragments' ), 11 );

		// Remove query strings from static resources (only on front-end).
		if ( $options['query_string'] ) {
			add_filter( 'script_loader_src', array( $this, 'remove_query_strings' ), 15, 1 );
			add_filter( 'style_loader_src', array( $this, 'remove_query_strings' ), 15, 1 );
		}

		// DNS prefetch.
		add_filter( 'wp_resource_hints', array( $this, 'prefetch_dns' ), 9, 2 );

		// Preconnect.
		add_filter( 'wp_resource_hints', array( $this, 'add_preconnect_urls' ), 10, 2 );

		// Filter comment template if lazy load is enabled.
		if ( isset( $options['lazy_load'] ) && $options['lazy_load']['enabled'] ) {
			add_filter( 'comments_template', array( $this, 'filter_comments_template' ), 100 );
		}

		add_filter( 'wp_revisions_to_keep', array( $this, 'set_revisions_to_keep' ), 10, 2 );
		add_filter( 'wphb_buffer', array( $this, 'wphb_add_viewport_meta_tag' ) );
	}

	/**
	 * Add viewport meta tag to the HTML content.
	 *
	 * @param string $html HTML content.
	 *
	 * @return string
	 */
	public function wphb_add_viewport_meta_tag( $html ) {
		$options = Settings::get_settings( 'advanced' );
		if ( isset( $options['viewport_meta'] ) && $options['viewport_meta'] ) {
			// Define the regex pattern for the viewport meta tag.
			$pattern = '/<meta[^>]*name=["\']viewport["\'][^>]*>/i';
			// Search for the viewport meta tag in the HTML content.
			if ( ! preg_match( $pattern, $html ) ) {
				$html = preg_replace( '#<head>#iU', '<head> <meta name="viewport" content="width=device-width, initial-scale=1">', $html, 1 );
			}
		}

		return $html;
	}

	/**
	 * *************************
	 * Remove query strings from static assets.
	 ***************************/

	/**
	 * Parse the src of script/style tags to remove the version query string.
	 *
	 * @param string $src  Script loader source path.
	 *
	 * @return string
	 */
	public function remove_query_strings( $src ) {
		$parts = preg_split( '/\?ver|\?timestamp/', $src );
		return $parts[0];
	}

	/**
	 * *************************
	 * Remove Emoji.
	 ***************************/

	/**
	 * Remove Emoji scripts from WordPress.
	 */
	public function remove_emoji() {
		remove_action( 'wp_head', 'print_emoji_detection_script', 7 );
		remove_action( 'admin_print_scripts', 'print_emoji_detection_script' );
		remove_action( 'wp_print_styles', 'print_emoji_styles' );
		remove_action( 'admin_print_styles', 'print_emoji_styles' );
		remove_filter( 'the_content_feed', 'wp_staticize_emoji' );
		remove_filter( 'comment_text_rss', 'wp_staticize_emoji' );
		remove_filter( 'wp_mail', 'wp_staticize_emoji_for_email' );
	}

	/**
	 * Remove Emoji icons from TinyMCE.
	 *
	 * @param array $plugins  An array of default TinyMCE plugins.
	 *
	 * @return array
	 */
	public function remove_emoji_tinymce( $plugins ) {
		if ( is_array( $plugins ) ) {
			return array_diff( $plugins, array( 'wpemoji' ) );
		}

		return array();
	}

	/**
	 * *************************
	 * Prefetch DNS.
	 ***************************/

	/**
	 * Prefetch DNS. Minimum required WordPress version is 4.6.
	 *
	 * @param array  $hints          URLs to print for resource hints.
	 * @param string $relation_type  The relation type the URLs are printed for, e.g. 'preconnect' or 'prerender'.
	 *
	 * @see https://make.wordpress.org/core/2016/07/06/resource-hints-in-4-6/
	 *
	 * @return array
	 */
	public function prefetch_dns( $hints, $relation_type ) {
		if ( 'dns-prefetch' !== $relation_type ) {
			return $hints;
		}

		if ( ! in_array( $this->font_awesome_domain, $hints, true ) ) {
			$this->font_awesome_domain = false;
		}

		if ( ! in_array( $this->google_font_domain, $hints, true ) ) {
			$this->google_font_domain = false;
		}

		$urls = Settings::get_setting( 'prefetch', 'advanced' );

		// If not urls set, return default WP hints array.
		if ( ! is_array( $urls ) || empty( $urls ) ) {
			return $hints;
		}

		$urls = array_map( 'esc_url', $urls );

		foreach ( $urls as $url ) {
			$hints[] = $url;
		}

		return $hints;
	}

	/**
	 * Optimize WooCommerce cart fragments.
	 *
	 * @since 2.2.0
	 */
	public function remove_cart_fragments() {
		$options = $this->get_options();

		if ( ! isset( $options['cart_fragments'] ) || ! $options['cart_fragments'] ) {
			return;
		}

		if ( ! function_exists( 'is_woocommerce' ) ) {
			return;
		}

		if ( 'all' === $options['cart_fragments'] || ( ! is_woocommerce() && ! is_cart() && ! is_checkout() ) ) {
			wp_dequeue_script( 'wc-cart-fragments' );
			wp_deregister_script( 'wc-cart-fragments' );
		}
	}

	/**
	 * Add preconnect resource hints to URLs.
	 *
	 * @since 3.0.0
	 *
	 * @param array  $hints          URLs to print for resource hints.
	 * @param string $relation_type  The relation type the URLs are printed for, e.g. 'preconnect' or 'prerender'.
	 *
	 * @return array
	 */
	public function add_preconnect_urls( $hints, $relation_type ) {
		if ( 'preconnect' !== $relation_type ) {
			return $hints;
		}

		$urls = Settings::get_setting( 'preconnect', 'advanced' );
		if ( ! is_array( $urls ) ) {
			$url = array();
		}

		if ( Utils::get_module( 'minify' )->get_cdn_status() && ! in_array( '//hb.wpmucdn.com', $urls, true ) ) {
			$urls[] = '//hb.wpmucdn.com';
		}

		if ( $this->font_awesome_domain && ! in_array( '//' . $this->font_awesome_domain, $urls, true ) ) {
			$urls[] = $this->font_awesome_domain . ' crossorigin';
		}

		if ( $this->google_font_domain && ! in_array( '//' . $this->google_font_domain, $urls, true ) ) {
			$urls[] = $this->google_font_domain;

			if ( ! in_array( '//fonts.gstatic.com', $urls, true ) ) {
				$urls[] = '//fonts.gstatic.com crossorigin';
			}
		}

		// If not urls set, return default WP hints array.
		if ( ! is_array( $urls ) || empty( $urls ) ) {
			return $hints;
		}

		foreach ( $urls as $url ) {
			$attr = explode( ' ', $url );
			$hint = array(
				'href' => esc_url( $attr[0] ),
			);

			if ( isset( $attr[1] ) && 'crossorigin' === $attr[1] ) {
				$hint['crossorigin'] = '';
			}

			$hints[] = $hint;
		}

		return $hints;
	}

	/**
	 * *************************
	 * Database cleanup.
	 ***************************/

	/**
	 * Get default fields for database cleanup.
	 *
	 * @return array
	 */
	public static function get_db_fields() {
		return array(
			'revisions'          => array(
				'title'   => __( 'Post Revisions', 'wphb' ),
				'tooltip' => __( "Historic versions of your posts and pages. If you don't need to revert to older versions, delete these entries", 'wphb' ),
			),
			'drafts'             => array(
				'title'   => __( 'Draft Posts', 'wphb' ),
				'tooltip' => __( "Draft posts are auto-saved versions of your posts and pages. If you don't use drafts, you can clear those entries here and move them to trash. Trashed posts can be permanently deleted below.", 'wphb' ),
			),
			'trash'              => array(
				'title'   => __( 'Trashed Posts', 'wphb' ),
				'tooltip' => __( "Posts or pages you've marked as trash but haven't permanently deleted yet", 'wphb' ),
			),
			'spam'               => array(
				'title'   => __( 'Spam Comments', 'wphb' ),
				'tooltip' => __( "Comments marked as spam that haven't been deleted yet", 'wphb' ),
			),
			'trash_comment'      => array(
				'title'   => __( 'Trashed Comments', 'wphb' ),
				'tooltip' => __( "Comments you've marked as trash but haven't permanently deleted yet", 'wphb' ),
			),
			'expired_transients' => array(
				'title'   => __( 'Expired Transients', 'wphb' ),
				'tooltip' => __( 'Cached data that themes and plugins have stored, except these ones have expired and can be deleted', 'wphb' ),
			),
			'transients'         => array(
				'title'   => __( 'All Transients', 'wphb' ),
				'tooltip' => __( 'Cached data that themes and plugins have stored, but may still be in use. Note: the next page to load could take a bit longer due to WordPress regenerating transients.', 'wphb' ),
			),
		);
	}

	/**
	 * Get data from the database.
	 *
	 * @param string $type Accepts: 'revisions', 'drafts', 'trash', 'spam', 'trash_comment',
	 *                     'expired_transients', 'transients', 'all'.
	 *
	 * @return int|array|stdClass
	 */
	public static function get_db_count( $type = 'all' ) {
		global $wpdb;

		$count = wp_cache_get( "wphb_db_optimization:$type" );

		if ( false === $count ) {
			switch ( $type ) {
				case 'revisions':
					$count = $wpdb->get_var( "SELECT COUNT(*) FROM $wpdb->posts WHERE post_type = 'revision' AND post_status = 'inherit'" ); // Db call ok.
					break;
				case 'drafts':
					$count = $wpdb->get_var( "SELECT COUNT(*) FROM $wpdb->posts WHERE ( post_status = 'draft' OR post_status = 'auto-draft' ) AND ( post_type = 'page' OR post_type = 'post' )" ); // Db call ok.
					break;
				case 'trash':
					$count = $wpdb->get_var( "SELECT COUNT(*) FROM $wpdb->posts WHERE post_status = 'trash'" ); // Db call ok.
					break;
				case 'spam':
					$count = $wpdb->get_var( "SELECT COUNT(*) FROM $wpdb->comments WHERE comment_approved = 'spam'" ); // Db call ok.
					break;
				case 'trash_comment':
					$count = $wpdb->get_var( "SELECT COUNT(*) FROM $wpdb->comments WHERE comment_approved = 'trash'" ); // Db call ok.
					break;
				case 'expired_transients':
					$count = $wpdb->get_var( "SELECT COUNT(*) FROM $wpdb->options WHERE option_name LIKE '\_transient\_timeout\__%%' AND option_value < UNIX_TIMESTAMP()" ); // Db call ok.
					break;
				case 'transients':
					$count = $wpdb->get_var( "SELECT COUNT(*) FROM $wpdb->options WHERE option_name LIKE '%_transient_%'" ); // Db call ok.
					break;
				case 'all':
				default:
					$count = $wpdb->get_row(
						"
					SELECT revisions, drafts, trash, spam, trash_comment, expired_transients, transients,
					       sum(revisions+drafts+trash+spam+trash_comment+expired_transients+transients) AS total
					FROM (
					  (SELECT
					    COUNT(CASE WHEN post_type = 'revision' AND post_status = 'inherit' THEN 1 ELSE NULL END) AS revisions,
					    COUNT(CASE WHEN ( post_status = 'draft' OR post_status = 'auto-draft' ) AND ( post_type = 'page' OR post_type = 'post' ) THEN 1 ELSE NULL END) AS drafts,
					    COUNT(CASE WHEN post_status = 'trash' THEN 1 ELSE NULL END) AS trash
					  FROM $wpdb->posts) as posts,
					  (SELECT
					    COUNT(CASE WHEN comment_approved = 'spam' THEN 1 ELSE NULL END) AS spam,
					    COUNT(CASE WHEN comment_approved = 'trash' THEN 1 ELSE NULL END) AS trash_comment
					  FROM $wpdb->comments) as comments,
					  (SELECT
					    COUNT(CASE WHEN option_name LIKE '\_transient\_timeout\__%%' AND option_value < UNIX_TIMESTAMP() THEN 1 ELSE NULL END ) AS expired_transients,
					    COUNT(CASE WHEN option_name LIKE '%_transient_%' THEN 1 ELSE NULL END) AS transients
					  FROM $wpdb->options) as options
					)"
					); // Db call ok.
					break;
			}

			wp_cache_set( "wphb_db_optimization:$type", $count );
		}

		return $count;
	}

	/**
	 * Delete database rows.
	 *
	 * @since 1.8
	 *
	 * @param string $type Accepts: 'revisions', 'drafts', 'trash', 'spam', 'trash_comment',
	 *                     'expired_transients', 'transients', 'all'.
	 *
	 * @return array|bool
	 */
	public function delete_db_data( $type ) {
		global $wpdb;

		/**
		 * Make sure that drafts always go after trash, because on first iteration we move drafts to trash and allow
		 * user to restore.
		 */
		$sql = array(
			'revisions'          => "SELECT ID FROM $wpdb->posts WHERE post_type = 'revision' AND post_status = 'inherit'",
			'trash'              => "SELECT ID FROM $wpdb->posts WHERE post_status = 'trash'",
			'drafts'             => "SELECT ID FROM $wpdb->posts WHERE ( post_status = 'draft' OR post_status = 'auto-draft' ) AND ( post_type = 'page' OR post_type = 'post' )",
			'spam'               => "SELECT comment_ID FROM $wpdb->comments WHERE comment_approved = 'spam'",
			'trash_comment'      => "SELECT comment_ID FROM $wpdb->comments WHERE comment_approved = 'trash'",
			'expired_transients' => "SELECT option_name FROM $wpdb->options
											WHERE option_name LIKE '\_transient\_timeout\__%%' AND option_value < UNIX_TIMESTAMP()",
			'transients'         => "SELECT option_name FROM $wpdb->options WHERE option_name LIKE '%_transient_%'",
		);

		if ( ! isset( $sql[ $type ] ) && 'all' !== $type ) {
			return false;
		}

		if ( 'all' === $type ) {
			$items = 0;
			foreach ( $sql as $type => $query ) {
				$items = $items + $this->delete( $query, $type );
			}
		} else {
			$items = $this->delete( $sql[ $type ], $type );
		}

		wp_cache_delete( "wphb_db_optimization:$type" );

		/**
		 * Fires after the database cleanup task.
		 *
		 * @since 1.9.2
		 *
		 * @param string $type   Data type that was cleared from the database. Can return following values: all,
		 *                       revisions, drafts, trash, spam, trash_comment, expired_transients, transients.
		 * @param int    $items  Number of items that was cleared from the database for the selected data type.
		 */
		do_action( 'wphb_delete_db_data', $type, $items );

		return array(
			'items' => $items,
			'left'  => self::get_db_count(), // Check for any non-deleted items.
		);
	}

	/**
	 * Delete items from the database using a provided query and item type.
	 *
	 * @since 1.8
	 *
	 * @access private
	 * @param  string $sql   SQL-query to fetch items.
	 * @param  string $type  Type of item to fetch.
	 *
	 * @return int
	 */
	private function delete( $sql, $type ) {
		global $wpdb;

		wp_cache_flush();
		$entries = $wpdb->get_col( $sql ); // Db call ok; no-cache okay.

		if ( 'revisions' === $type || 'drafts' === $type || 'trash' === $type ) {
			$func = 'wp_delete_post';
		} elseif ( 'spam' === $type || 'trash_comment' === $type ) {
			$func = 'wp_delete_comment';
		} elseif ( 'expired_transients' === $type && function_exists( 'delete_expired_transients' ) ) {
			delete_expired_transients();
			return count( $entries );
		} else {
			$func = 'delete_option';
		}

		$items = 0;
		foreach ( $entries as $entry ) {
			if ( 'delete_option' === $func || 'drafts' === $type ) {
				// No option to force delete in delete_option function.
				$del = call_user_func( $func, $entry );
			} else {
				// Force delete entries (without moving to trash).
				$del = call_user_func( $func, $entry, true );
			}

			if ( null !== $del && ! is_wp_error( $del ) ) {
				$items++;
			}
		}

		return $items;
	}

	/**
	 * *************************
	 * HB cleanup.
	 ***************************/

	/**
	 * Cleanup cron task.
	 *
	 * @since 1.8.1
	 */
	public function hb_cleanup_cron() {
		global $wpdb;

		// Select 100 entries.
		$entries = $wpdb->get_col( "SELECT ID FROM $wpdb->posts WHERE post_type = 'wphb_minify_group' LIMIT 0, 100" ); // db call ok; no-cache ok.

		// Delete them properly.
		foreach ( $entries as $entry ) {
			if ( get_post( $entry ) && 'wphb_minify_group' === get_post_type( $entry ) ) {
				wp_delete_post( $entry, true );
			}
		}

		// Reschedule another batch if any entries left.
		$count = $wpdb->get_var( "SELECT COUNT(*) FROM $wpdb->posts WHERE post_type = 'wphb_minify_group'" ); // db call ok; no-cache ok.

		if ( 0 < (int) $count ) {
			wp_schedule_single_event( time(), 'wphb_hummingbird_cleanup' );
		} else {
			wp_clear_scheduled_hook( 'wphb_hummingbird_cleanup' );
		}

		return true;
	}

	/**
	 * *************************
	 * System Information.
	 ***************************/

	/**
	 * Get PHP information for System Information.
	 *
	 * @since 1.8.2
	 *
	 * @return array
	 */
	public static function get_php_info() {
		$php_info = array();
		$php_vars = array(
			'max_execution_time',
			'open_basedir',
			'memory_limit',
			'upload_max_filesize',
			'post_max_size',
			'display_errors',
			'log_errors',
			'track_errors',
			'session.auto_start',
			'session.cache_expire',
			'session.cache_limiter',
			'session.cookie_domain',
			'session.cookie_httponly',
			'session.cookie_lifetime',
			'session.cookie_path',
			'session.cookie_secure',
			'session.gc_divisor',
			'session.gc_maxlifetime',
			'session.gc_probability',
			'session.referer_check',
			'session.save_handler',
			'session.save_path',
			'session.serialize_handler',
			'session.use_cookies',
			'session.use_only_cookies',
		);

		$php_info[ __( 'Version', 'wphb' ) ] = phpversion();
		foreach ( $php_vars as $setting ) {
			$php_info[ $setting ] = ini_get( $setting );
		}
		$levels          = array();
		$error_reporting = error_reporting();

		$extension_constants = array(
			'E_ERROR',
			'E_WARNING',
			'E_PARSE',
			'E_NOTICE',
			'E_CORE_ERROR',
			'E_CORE_WARNING',
			'E_COMPILE_ERROR',
			'E_COMPILE_WARNING',
			'E_USER_ERROR',
			'E_USER_WARNING',
			'E_USER_NOTICE',
			'E_STRICT',
			'E_RECOVERABLE_ERROR',
			'E_DEPRECATED',
			'E_USER_DEPRECATED',
			'E_ALL',
		);

		foreach ( $extension_constants as $level ) {
			if ( defined( $level ) ) {
				$c = constant( $level );
				if ( $error_reporting & $c ) {
					$levels[ $c ] = $level;
				}
			}
		}
		$php_info[ __( 'Error Reporting', 'wphb' ) ] = implode( '<br>', $levels );
		$extensions                                  = get_loaded_extensions();
		natcasesort( $extensions );
		$php_info[ __( 'Extensions', 'wphb' ) ] = implode( '<br>', $extensions );

		return $php_info;
	}

	/**
	 * Get Database information for System Information.
	 *
	 * @since 1.8.2
	 *
	 * @return array
	 */
	public static function get_db_info() {
		global $wpdb;
		$dump_mysql = array();
		$mysql_vars = array(
			'key_buffer_size'    => true,   // Key cache size limit.
			'max_allowed_packet' => false,  // Individual query size limit.
			'max_connections'    => false,  // Max number of client connections.
			'query_cache_limit'  => true,   // Individual query cache size limit.
			'query_cache_size'   => true,   // Total cache size limit.
			'query_cache_type'   => 'ON',   // Query cache on or off.
		);
		$extra_info = array();
		$variables  = $wpdb->get_results( "SHOW VARIABLES WHERE Variable_name IN ( '" . implode( "', '", array_keys( $mysql_vars ) ) . "' )" ); // db call ok; no-cache ok.

		$dbh = $wpdb->dbh;
		if ( is_resource( $dbh ) ) {
			$driver  = 'mysql';
			$version = function_exists( 'mysqli_get_server_info' ) ? mysqli_get_server_info( $dbh ) : mysql_get_server_info( $dbh );
		} elseif ( is_object( $dbh ) ) {
			$driver = get_class( $dbh );
			if ( method_exists( $dbh, 'db_version' ) ) {
				$version = $dbh->db_version();
			} elseif ( isset( $dbh->server_info ) ) {
				$version = $dbh->server_info;
			} elseif ( isset( $dbh->server_version ) ) {
				$version = $dbh->server_version;
			} else {
				$version = __( 'Unknown', 'wphb' );
			}
			if ( isset( $dbh->client_info ) ) {
				$extra_info['Driver version'] = $dbh->client_info;
			}
			if ( isset( $dbh->host_info ) ) {
				$extra_info['Connection info'] = $dbh->host_info;
			}
		} else {
			$version = __( 'Unknown', 'wphb' );
			$driver  = __( 'Unknown', 'wphb' );
		}
		$extra_info['Database']     = $wpdb->dbname;
		$extra_info['Charset']      = $wpdb->charset;
		$extra_info['Collate']      = $wpdb->collate;
		$extra_info['Table Prefix'] = $wpdb->prefix;

		$dump_mysql['Server Version'] = $version;
		$dump_mysql['Driver']         = $driver;
		foreach ( $extra_info as $key => $val ) {
			$dump_mysql[ $key ] = $val;
		}
		foreach ( $mysql_vars as $key => $val ) {
			$dump_mysql[ $key ] = $val;
		}
		foreach ( $variables as $item ) {
			if ( is_numeric( $item->Value ) && ( $item->Value >= ( 1024 * 1024 ) ) ) {
				$val = size_format( $item->Value );
			}
			$dump_mysql[ $item->Variable_name ] = $val;
		}

		return $dump_mysql;
	}

	/**
	 * Get WordPress Installation information for System Information.
	 *
	 * @since 1.8.2
	 *
	 * @return array
	 */
	public static function get_wp_info() {
		global $wp_version;
		$dump_wp                      = array();
		$wp_consts                    = array(
			'ABSPATH',
			'WP_CONTENT_DIR',
			'WP_PLUGIN_DIR',
			'WPINC',
			'WP_LANG_DIR',
			'UPLOADBLOGSDIR',
			'UPLOADS',
			'WP_TEMP_DIR',
			'SUNRISE',
			'WP_ALLOW_MULTISITE',
			'MULTISITE',
			'SUBDOMAIN_INSTALL',
			'DOMAIN_CURRENT_SITE',
			'PATH_CURRENT_SITE',
			'SITE_ID_CURRENT_SITE',
			'BLOGID_CURRENT_SITE',
			'BLOG_ID_CURRENT_SITE',
			'COOKIE_DOMAIN',
			'COOKIEPATH',
			'SITECOOKIEPATH',
			'DISABLE_WP_CRON',
			'ALTERNATE_WP_CRON',
			'DISALLOW_FILE_MODS',
			'WP_HTTP_BLOCK_EXTERNAL',
			'WP_ACCESSIBLE_HOSTS',
			'WP_DEBUG',
			'WP_DEBUG_LOG',
			'WP_DEBUG_DISPLAY',
			'ERRORLOGFILE',
			'SCRIPT_DEBUG',
			'WP_LANG',
			'WP_MAX_MEMORY_LIMIT',
			'WP_MEMORY_LIMIT',
			'WPMU_ACCEL_REDIRECT',
			'WPMU_SENDFILE',
		);
		$dump_wp['WordPress Version'] = $wp_version;
		foreach ( $wp_consts as $const ) {
			$dump_wp[ $const ] = self::format_constant( $const );
		}

		return $dump_wp;
	}


	/**
	 * Get server information for System Information.
	 *
	 * @since 1.8.2
	 *
	 * @return array
	 */
	public static function get_server_info() {
		$dump_server = array();
		$server      = explode( ' ', wp_unslash( $_SERVER['SERVER_SOFTWARE'] ) ); // Input var ok.
		$server      = explode( '/', reset( $server ) );

		if ( isset( $server[1] ) ) {
			$server_version = $server[1];
		} else {
			$server_version = 'Unknown';
		}

		$dump_server[ __( 'Software Name', 'wphb' ) ]     = $server[0];
		$dump_server[ __( 'Software Version', 'wphb' ) ]  = $server_version;
		$dump_server[ __( 'Server IP', 'wphb' ) ]         = isset( $_SERVER['SERVER_ADDR'] ) ? wp_unslash( $_SERVER['SERVER_ADDR'] ) : __( 'undefined', 'wphb' );
		$dump_server[ __( 'Server Hostname', 'wphb' ) ]   = isset( $_SERVER['SERVER_NAME'] ) ? wp_unslash( $_SERVER['SERVER_NAME'] ) : __( 'undefined', 'wphb' );
		$dump_server[ __( 'Server Admin', 'wphb' ) ]      = isset( $_SERVER['SERVER_ADMIN'] ) ? wp_unslash( $_SERVER['SERVER_ADMIN'] ) : __( 'undefined', 'wphb' );
		$dump_server[ __( 'Server local time', 'wphb' ) ] = date( 'Y-m-d H:i:s (\U\T\C P)' );
		$dump_server[ __( 'Operating System', 'wphb' ) ]  = @php_uname( 's' );
		$dump_server[ __( 'OS Hostname', 'wphb' ) ]       = @php_uname( 'n' );
		$dump_server[ __( 'OS Version', 'wphb' ) ]        = @php_uname( 'v' );

		return $dump_server;
	}

	/**
	 * Helper function.
	 *
	 * @since 1.8.2
	 *
	 * @param string $constant  Name of a PHP const.
	 *
	 * @return string
	 */
	private static function format_constant( $constant ) {
		if ( ! defined( $constant ) ) {
			return '<em>' . __( 'undefined', 'wphb' ) . '</em>';
		}

		$val = constant( $constant );
		if ( ! is_bool( $val ) ) {
			return $val;
		} elseif ( ! $val ) {
			return __( 'FALSE', 'wphb' );
		} else {
			return __( 'TRUE', 'wphb' );
		}
	}


	/**
	 * Pluck all orphaned meta fields that belong to Hummingbird.
	 *
	 * Difference from above method, it will only include actual orphaned data, while with the method
	 * above, we need to subtract the number of valid assets.
	 *
	 * @since 2.7.0
	 *
	 * @return int.
	 */
	public function get_orphaned_ao_complex() {
		$count = wp_cache_get( 'wphb_ao_orphaned_data' );

		if ( false === $count ) {
			global $wpdb;

			$search_fields   = implode( "', '", Minify::get_postmeta_fields() );
			$database_prefix = $wpdb->get_blog_prefix( get_current_blog_id() );
			$posts_table     = $database_prefix . 'posts';
			$post_meta_table = $database_prefix . 'postmeta';

			$count = $wpdb->get_var(
				"SELECT COUNT( post_id ) FROM $post_meta_table A
                LEFT JOIN $posts_table B
				ON A.post_id = B.ID
				WHERE A.meta_key IN ('$search_fields')
				AND B.ID IS NULL"
			); // Db call ok.
		}

		wp_cache_set( 'wphb_ao_orphaned_data', $count );

		return $count;
	}

	/**
	 * Clear out a set number of orphaned asset optimization data.
	 *
	 * @since 2.7.0
	 *
	 * @param int $rows  Number of rows to clear.
	 */
	public function purge_orphaned_step( $rows ) {
		global $wpdb;

		$search_fields   = implode( "', '", Minify::get_postmeta_fields() );
		$database_prefix = $wpdb->get_blog_prefix( get_current_blog_id() );
		$posts_table     = $database_prefix . 'posts';
		$post_meta_table = $database_prefix . 'postmeta';

		$items = $wpdb->get_col(
			$wpdb->prepare(
				"SELECT meta_id FROM $post_meta_table A
                LEFT JOIN $posts_table B
				ON A.post_id = B.ID
				WHERE A.meta_key IN ('$search_fields')
				AND B.ID IS NULL LIMIT %d",
				$rows
			)
		); // Db call ok.

		if ( count( $items ) > 0 ) {
			$ids = implode( ',', array_map( 'intval', $items ) );
			$wpdb->query( "DELETE FROM $post_meta_table WHERE meta_id IN($ids)" );
		}

		// Remove count cache.
		wp_cache_delete( 'wphb_ao_orphaned_data' );

		/** This might be a better alternative - just try to force purge everything.
		$sql = "DELETE A FROM {$post_meta_table} AS A
				LEFT JOIN {$posts_table} AS B ON A.post_id = B.ID
				WHERE A.meta_key IN ('{$search_fields}')
				AND B.ID IS NULL;";
		*/
	}

	/**
	 * *************************
	 * Comment lazy loading.
	 ***************************/

	/**
	 * Enqueue lazy load scripts on single page/post.
	 *
	 * @since 2.5.0
	 */
	public function enqueue_global() {
		global $post;
		$lazy_load_comment_js = is_singular();
		$lazy_load_comment_js = apply_filters( 'wphb_lazy_load_comment_js', $lazy_load_comment_js );
		// Do not load sitewide.
		if ( ! $lazy_load_comment_js ) {
			return;
		}

		wp_enqueue_script(
			'wphb-lazy-load',
			WPHB_DIR_URL . 'admin/assets/js/wphb-lazy-load.min.js',
			array(),
			WPHB_VERSION,
			true
		);

		$separate_comments = get_transient( 'wphb-separate-comments' );
		$comment_form      = '';
		$preload_comment   = false;

		$preload = Settings::get_settings( 'advanced' );

		if ( isset( $preload['lazy_load']['preload'] ) && $preload['lazy_load']['preload'] ) {
			$cpage_num       = $this->wphb_get_cpage_num();
			$preload_comment = true;

			if ( class_exists( 'woocommerce' ) ) {
				global $product;
				$product = wc_get_product( $post->ID );
			}

			remove_filter( 'comments_template', array( $this, 'filter_comments_template' ), 100 );

			if ( ! empty( $cpage_num ) ) {
				set_query_var( 'cpage', $cpage_num );

				// Adding filters.
				add_filter( 'option_page_comments', array( $this, 'filter_option_page_comments' ), 100 );
				add_filter( 'comments_template', array( $this, 'reset_wp_query_max_num_comment_pages' ), 1 );
				add_filter( 'option_comment_order', array( $this, 'filter_option_comment_order' ), 100 );
			}

			ob_start();
			comments_template( '', $separate_comments );
			$comment_form = ob_get_contents();
			ob_end_clean();

			add_filter( 'comments_template', array( $this, 'filter_comments_template' ), 100 );
			remove_filter( 'comments_template', array( $this, 'reset_wp_query_max_num_comment_pages' ), 1 );
		}

		wp_localize_script(
			'wphb-lazy-load',
			'wphbGlobal',
			array(
				'ajaxurl'        => admin_url( 'admin-ajax.php' ),
				'commentForm'    => $comment_form,
				'preloadComment' => $preload_comment,
			)
		);
	}

	/**
	 * Returns total comment pages.
	 *
	 * @return int Total comment pages.
	 */
	public function wphb_get_cpage_num() {
		global $post;
		$cpage_num = get_query_var( 'cpage' );

		if ( ! $cpage_num ) {
			$cpage_num = 1;
		}

		remove_filter( 'option_page_comments', '__return_true', 100 );
		$page_comments = (int) get_option( 'page_comments' );

		if ( 0 === $page_comments ) {
			add_filter( 'option_page_comments', '__return_true', 10 );
		}

		$get_comments_object = get_approved_comments( $post->ID );
		$total_comment_pages = get_comment_pages_count( $get_comments_object );

		if ( 0 === $page_comments ) {
			remove_filter( 'option_page_comments', '__return_true', 10 );
		}

		$comments_page_order = get_option( 'default_comments_page' ); // Possible values : newest, oldest.

		if ( 'newest' === $comments_page_order && 1 === $cpage_num ) {
			$cpage_num = $total_comment_pages;
		}

		return $cpage_num;
	}

	/**
	 * Checks for the user agent to validate if the visitor is a bot
	 *
	 * @since 2.5.0
	 *
	 * @return bool
	 */
	public function visitor_is_a_bot() {
		/* No User agent, Or the useragent string matches the basic pattern */
		if ( ! isset( $_SERVER['HTTP_USER_AGENT'] ) || preg_match( '/bot|crawl|slurp|spider/i', sanitize_key( wp_unslash( $_SERVER['HTTP_USER_AGENT'] ) ) ) ) {
			return true;
		}

		return false;
	}

	/**
	 * Validates if we should be lazy loading comments or not
	 *
	 * @since 2.5.0
	 *
	 * @param array $options plugin settings.
	 *
	 * @return bool True|False
	 */
	public function should_lazy_load( $options ) {
		global $wp_query;

		$lazy_load = true;

		if ( $this->visitor_is_a_bot() ) {
			$lazy_load = false;
		}

		$comment_count = get_comments_number();

		if ( ! $comment_count ) {
			// If there are no comments.
			$lazy_load = false;
		} elseif ( (int) $options['lazy_load']['threshold'] > $comment_count ) {
			// if threshold is lower than total comment count.
			$lazy_load = false;
		} elseif ( ! empty( $wp_query->comment_count ) && (int) $options['lazy_load']['threshold'] > $wp_query->comment_count ) {
			// If there is a comment pagination, and the comment_count for the page < threshold.
			$lazy_load = false;
		}

		return $lazy_load;
	}

	/**
	 * Filters the default comment template to Lazy Load markup ( Button or a Scroll div )
	 *
	 * @since 2.5.0
	 *
	 * @param string $template Current comment template.
	 *
	 * @return string HTML markup for the button or a div used to load comments template on scroll
	 */
	public function filter_comments_template( $template ) {
		$options = $this->get_options();

		$should_lazy_load = $this->should_lazy_load( $options );

		/* Return the original template if we should not lazy load */
		if ( ! apply_filters( 'wphb_should_lazy_load_comment', $should_lazy_load ) ) {
			return $template;
		}

		/* Set "separate-comments" transient if not set already */
		if ( false === get_transient( 'wphb-separate-comments' ) ) {
			global $wp_query;

			// Check if separate comments is set.
			$separate_comments = ! empty( $wp_query ) && ! empty( $wp_query->comments_by_type ) ? 1 : 0;

			set_transient( 'wphb-separate-comments', $separate_comments, 60 );
		}

		set_query_var( 'lazy_load_settings', $options['lazy_load'] );

		return WPHB_DIR_PATH . 'core/views/comment-template.php';
	}

	/**
	 * Strip parameters.
	 *
	 * @since 2.5.0
	 *
	 * @param string $link  URL.
	 *
	 * @return bool|string
	 */
	public function strip_params( $link ) {
		if ( ! isset( $_GET['action'] ) || 'get_comments_template' !== sanitize_key( wp_unslash( $_GET['action'] ) ) ) {
			return $link;
		}

		return remove_query_arg( array( 'action', 'id', '_nonce' ), $link );
	}

	/**
	 * Ajax handler to load the actual comment template on front-end.
	 *
	 * @since 2.5.0
	 */
	public function comment_template() {
		if ( empty( $_GET['_nonce'] ) || ! wp_verify_nonce( wp_unslash( $_GET['_nonce'] ), 'comments_template' ) ) {
			$message = '<div class="wphb-lazy-load-error sui-error">' . esc_html__( 'We could not validate the request, try reloading the page.', 'wphb' ) . '</div>';
			wp_send_json_error( array( 'content' => $message ) );
		}

		/* Return an error if post id isn't set */
		if ( empty( $_GET['id'] ) ) {
			$message = '<div class="wphb-lazy-load-error sui-error">' . esc_html__( 'Something went wrong. Try reloading the page to see if the comments load for you.', 'wphb' ) . '</div>';
			wp_send_json_error( array( 'content' => $message ) );
		}

		$cpage_num = ! empty( $_GET['cpage_num'] ) ? absint( $_GET['cpage_num'] ) : '';

		$separate_comments = get_transient( 'wphb-separate-comments' );

		/* Remove our comment template filter to be able to get the original content */
		remove_filter( 'comments_template', array( $this, 'filter_comments_template' ), 100 );

		/**
		 * Allow plugin/themes to hook-in, to enable support for loading custom comments template over AJAX
		 */
		do_action( 'wphb_ajax_get_comments_template' );

		query_posts(
			array(
				'p'         => absint( $_GET['id'] ),
				'post_type' => 'any',
			)
		);

		/* Restore original Post Data */
		wp_reset_postdata();
		if ( have_posts() ) {
			the_post();

			// Workaround :( .
			$orig_uri               = $_SERVER['REQUEST_URI'];
			$_SERVER['REQUEST_URI'] = get_the_permalink( get_the_ID() );
			if ( ! empty( $cpage_num ) ) {
				set_query_var( 'cpage', $cpage_num );
				/**
				 * Override page_comments decision set from discussion settings page.
				 * By default, comment pagination is ignored when page_comments is false.
				 * See in function comments_template() in wp-includes/comment-template.php
				 * We need it always true to get comments for specific cpage.
				 */
				add_filter( 'option_page_comments', array( $this, 'filter_option_page_comments' ), 100 );

				/**
				 * As we override page_comments decision, function comments_template() calculate max_num_comment_pages and set to wp_query
				 * Theme comment template tries to generate comment pagination by
				 * using the_comments_pagination/get_the_comments_pagination function
				 * This function needs comment page count. If comment page count is more than 1 , it generates pagination
				 * get_comment_pages_count() function usages max_num_comment_pages
				 * We don't want to show pagination, We will reset max_num_comment_pages value to 1 so that get_comment_pages_count retuns 1
				 * comments_template function usages a filter for comments_template file.
				 * We will use this filter to reset wp_query->max_num_comment_pages.
				 */
				add_filter( 'comments_template', array( $this, 'reset_wp_query_max_num_comment_pages' ), 1 );

				/**
				 * Override comment_order decision set from discussion settings page.
				 * When default_comments_page value is 'newest' we want comment_order 'desc'.
				 * When default_comments_page value is 'oldest' we want comment_order 'asc'.
				 */
				add_filter( 'option_comment_order', array( $this, 'filter_option_comment_order' ), 100 );

			}
			ob_start();

			comments_template( '', $separate_comments );
			$content = ob_get_contents();

			ob_end_clean();
			$_SERVER['REQUEST_URI'] = $orig_uri;
		}

		if ( ! empty( $content ) ) {
			wp_send_json_success( array( 'content' => $content ) );
		}

		die();
	}

	/**
	 * Add Lazy load action to the list of supported ajax action in Divi theme comment template.
	 *
	 * @since 2.5.0
	 *
	 * @return array
	 */
	public function add_divi_support() {
		return array( 'action' => array( 'get_comments_template' ) );
	}

	/**
	 * Set page_comments option true.
	 *
	 * Return TRUE only one time when the filter option_page_comments called in
	 * function comments_template() in wp-includes/comment-template.php
	 *
	 * @since 2.5.0
	 *
	 * @param mixed $value  Value.
	 *
	 * @return bool|mixed
	 */
	public function filter_option_page_comments( $value ) {
		static $n;

		if ( ! empty( $n ) ) {
			return $value;
		}

		$n = 1;

		return true;
	}

	/**
	 * This is a fake callback function for comments_template filter
	 * We will not change $template value
	 * We will change max_num_comment_pages var from $wp_query object
	 *
	 * @since 2.5.0
	 *
	 * @param string $template The path to the theme template file.
	 *
	 * @return string
	 */
	public function reset_wp_query_max_num_comment_pages( $template ) {
		global $wp_query;
		$wp_query->max_num_comment_pages = 1;
		return $template;
	}

	/**
	 * Filter comment_order option value.
	 * When default_comments_page value is 'newest' we want comment_order 'desc'.
	 * When default_comments_page value is 'oldest' we want comment_order 'asc'.
	 *
	 * @since 2.5.0
	 *
	 * @param string $order  Order type.
	 *
	 * @return string
	 */
	public function filter_option_comment_order( $order ) {
		$dcp = get_option( 'default_comments_page' );
		return ( 'newest' === $dcp ) ? 'desc' : 'asc';
	}

	/**
	 * Set the post revisions.
	 *
	 * @param int     $num  Number of revisions to store.
	 * @param WP_Post $post Post object.
	 * @return int
	 **/
	public function set_revisions_to_keep( $num, $post ) {
		$options = Settings::get_settings( 'advanced' );
		if ( isset( $options['post_revisions'] ) && $options['post_revisions'] >= 0 ) {
			return (int) $options['post_revisions'];
		}

		return $num;
	}
}
