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<?php
/**
 * Core Comment API
 *
 * @package WordPress
 * @subpackage Comment
 */

/**
 * Checks whether a comment passes internal checks to be allowed to add.
 *
 * If manual comment moderation is set in the administration, then all checks,
 * regardless of their type and substance, will fail and the function will
 * return false.
 *
 * If the number of links exceeds the amount in the administration, then the
 * check fails. If any of the parameter contents contain any disallowed words,
 * then the check fails.
 *
 * If the comment author was approved before, then the comment is automatically
 * approved.
 *
 * If all checks pass, the function will return true.
 *
 * @since 1.2.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param string $author       Comment author name.
 * @param string $email        Comment author email.
 * @param string $url          Comment author URL.
 * @param string $comment      Content of the comment.
 * @param string $user_ip      Comment author IP address.
 * @param string $user_agent   Comment author User-Agent.
 * @param string $comment_type Comment type, either user-submitted comment,
 *                             trackback, or pingback.
 * @return bool If all checks pass, true, otherwise false.
 */
function check_comment( $author, $email, $url, $comment, $user_ip, $user_agent, $comment_type ) {
	global $wpdb;

// If manual moderation is enabled, skip all checks and return false.
	if ( 1 == get_option( 'comment_moderation' ) ) {
		return false;
	}

/** This filter is documented in wp-includes/comment-template.php */
	$comment = apply_filters( 'comment_text', $comment, null, array() );

// Check for the number of external links if a max allowed number is set.
	$max_links = get_option( 'comment_max_links' );
	if ( $max_links ) {
		$num_links = preg_match_all( '/<a [^>]*href/i', $comment, $out );

/**
		 * Filters the number of links found in a comment.
		 *
		 * @since 3.0.0
		 * @since 4.7.0 Added the `$comment` parameter.
		 *
		 * @param int    $num_links The number of links found.
		 * @param string $url       Comment author's URL. Included in allowed links total.
		 * @param string $comment   Content of the comment.
		 */
		$num_links = apply_filters( 'comment_max_links_url', $num_links, $url, $comment );

/*
		 * If the number of links in the comment exceeds the allowed amount,
		 * fail the check by returning false.
		 */
		if ( $num_links >= $max_links ) {
			return false;
		}
	}

$mod_keys = trim( get_option( 'moderation_keys' ) );

// If moderation 'keys' (keywords) are set, process them.
	if ( ! empty( $mod_keys ) ) {
		$words = explode( "\n", $mod_keys );

foreach ( (array) $words as $word ) {
			$word = trim( $word );

// Skip empty lines.
			if ( empty( $word ) ) {
				continue;
			}

/*
			 * Do some escaping magic so that '#' (number of) characters in the spam
			 * words don't break things:
			 */
			$word = preg_quote( $word, '#' );

/*
			 * Check the comment fields for moderation keywords. If any are found,
			 * fail the check for the given field by returning false.
			 */
			$pattern = "#$word#iu";
			if ( preg_match( $pattern, $author ) ) {
				return false;
			}
			if ( preg_match( $pattern, $email ) ) {
				return false;
			}
			if ( preg_match( $pattern, $url ) ) {
				return false;
			}
			if ( preg_match( $pattern, $comment ) ) {
				return false;
			}
			if ( preg_match( $pattern, $user_ip ) ) {
				return false;
			}
			if ( preg_match( $pattern, $user_agent ) ) {
				return false;
			}
		}
	}

/*
	 * Check if the option to approve comments by previously-approved authors is enabled.
	 *
	 * If it is enabled, check whether the comment author has a previously-approved comment,
	 * as well as whether there are any moderation keywords (if set) present in the author
	 * email address. If both checks pass, return true. Otherwise, return false.
	 */
	if ( 1 == get_option( 'comment_previously_approved' ) ) {
		if ( 'trackback' !== $comment_type && 'pingback' !== $comment_type && '' !== $author && '' !== $email ) {
			$comment_user = get_user_by( 'email', wp_unslash( $email ) );
			if ( ! empty( $comment_user->ID ) ) {
				$ok_to_comment = $wpdb->get_var( $wpdb->prepare( "SELECT comment_approved FROM $wpdb->comments WHERE user_id = %d AND comment_approved = '1' LIMIT 1", $comment_user->ID ) );
			} else {
				// expected_slashed ($author, $email)
				$ok_to_comment = $wpdb->get_var( $wpdb->prepare( "SELECT comment_approved FROM $wpdb->comments WHERE comment_author = %s AND comment_author_email = %s and comment_approved = '1' LIMIT 1", $author, $email ) );
			}
			if ( ( 1 == $ok_to_comment ) &&
				( empty( $mod_keys ) || ! str_contains( $email, $mod_keys ) ) ) {
					return true;
			} else {
				return false;
			}
		} else {
			return false;
		}
	}
	return true;
}

/**
 * Retrieves the approved comments for a post.
 *
 * @since 2.0.0
 * @since 4.1.0 Refactored to leverage WP_Comment_Query over a direct query.
 *
 * @param int   $post_id The ID of the post.
 * @param array $args    {
 *     Optional. See WP_Comment_Query::__construct() for information on accepted arguments.
 *
 *     @type int    $status  Comment status to limit results by. Defaults to approved comments.
 *     @type int    $post_id Limit results to those affiliated with a given post ID.
 *     @type string $order   How to order retrieved comments. Default 'ASC'.
 * }
 * @return WP_Comment[]|int[]|int The approved comments, or number of comments if `$count`
 *                                argument is true.
 */
function get_approved_comments( $post_id, $args = array() ) {
	if ( ! $post_id ) {
		return array();
	}

$defaults    = array(
		'status'  => 1,
		'post_id' => $post_id,
		'order'   => 'ASC',
	);
	$parsed_args = wp_parse_args( $args, $defaults );

$query = new WP_Comment_Query();
	return $query->query( $parsed_args );
}

/**
 * Retrieves comment data given a comment ID or comment object.
 *
 * If an object is passed then the comment data will be cached and then returned
 * after being passed through a filter. If the comment is empty, then the global
 * comment variable will be used, if it is set.
 *
 * @since 2.0.0
 *
 * @global WP_Comment $comment Global comment object.
 *
 * @param WP_Comment|string|int $comment Comment to retrieve.
 * @param string                $output  Optional. The required return type. One of OBJECT, ARRAY_A, or ARRAY_N, which
 *                                       correspond to a WP_Comment object, an associative array, or a numeric array,
 *                                       respectively. Default OBJECT.
 * @return WP_Comment|array|null Depends on $output value.
 */
function get_comment( $comment = null, $output = OBJECT ) {
	if ( empty( $comment ) && isset( $GLOBALS['comment'] ) ) {
		$comment = $GLOBALS['comment'];
	}

if ( $comment instanceof WP_Comment ) {
		$_comment = $comment;
	} elseif ( is_object( $comment ) ) {
		$_comment = new WP_Comment( $comment );
	} else {
		$_comment = WP_Comment::get_instance( $comment );
	}

if ( ! $_comment ) {
		return null;
	}

/**
	 * Fires after a comment is retrieved.
	 *
	 * @since 2.3.0
	 *
	 * @param WP_Comment $_comment Comment data.
	 */
	$_comment = apply_filters( 'get_comment', $_comment );

if ( OBJECT === $output ) {
		return $_comment;
	} elseif ( ARRAY_A === $output ) {
		return $_comment->to_array();
	} elseif ( ARRAY_N === $output ) {
		return array_values( $_comment->to_array() );
	}
	return $_comment;
}

/**
 * Retrieves a list of comments.
 *
 * The comment list can be for the blog as a whole or for an individual post.
 *
 * @since 2.7.0
 *
 * @param string|array $args Optional. Array or string of arguments. See WP_Comment_Query::__construct()
 *                           for information on accepted arguments. Default empty string.
 * @return WP_Comment[]|int[]|int List of comments or number of found comments if `$count` argument is true.
 */
function get_comments( $args = '' ) {
	$query = new WP_Comment_Query();
	return $query->query( $args );
}

/**
 * Retrieves all of the WordPress supported comment statuses.
 *
 * Comments have a limited set of valid status values, this provides the comment
 * status values and descriptions.
 *
 * @since 2.7.0
 *
 * @return string[] List of comment status labels keyed by status.
 */
function get_comment_statuses() {
	$status = array(
		'hold'    => __( 'Unapproved' ),
		'approve' => _x( 'Approved', 'comment status' ),
		'spam'    => _x( 'Spam', 'comment status' ),
		'trash'   => _x( 'Trash', 'comment status' ),
	);

return $status;
}

/**
 * Gets the default comment status for a post type.
 *
 * @since 4.3.0
 *
 * @param string $post_type    Optional. Post type. Default 'post'.
 * @param string $comment_type Optional. Comment type. Default 'comment'.
 * @return string Either 'open' or 'closed'.
 */
function get_default_comment_status( $post_type = 'post', $comment_type = 'comment' ) {
	switch ( $comment_type ) {
		case 'pingback':
		case 'trackback':
			$supports = 'trackbacks';
			$option   = 'ping';
			break;
		default:
			$supports = 'comments';
			$option   = 'comment';
			break;
	}

// Set the status.
	if ( 'page' === $post_type ) {
		$status = 'closed';
	} elseif ( post_type_supports( $post_type, $supports ) ) {
		$status = get_option( "default_{$option}_status" );
	} else {
		$status = 'closed';
	}

/**
	 * Filters the default comment status for the given post type.
	 *
	 * @since 4.3.0
	 *
	 * @param string $status       Default status for the given post type,
	 *                             either 'open' or 'closed'.
	 * @param string $post_type    Post type. Default is `post`.
	 * @param string $comment_type Type of comment. Default is `comment`.
	 */
	return apply_filters( 'get_default_comment_status', $status, $post_type, $comment_type );
}

/**
 * Retrieves the date the last comment was modified.
 *
 * @since 1.5.0
 * @since 4.7.0 Replaced caching the modified date in a local static variable
 *              with the Object Cache API.
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param string $timezone Which timezone to use in reference to 'gmt', 'blog', or 'server' locations.
 * @return string|false Last comment modified date on success, false on failure.
 */
function get_lastcommentmodified( $timezone = 'server' ) {
	global $wpdb;

$timezone = strtolower( $timezone );
	$key      = "lastcommentmodified:$timezone";

$comment_modified_date = wp_cache_get( $key, 'timeinfo' );
	if ( false !== $comment_modified_date ) {
		return $comment_modified_date;
	}

switch ( $timezone ) {
		case 'gmt':
			$comment_modified_date = $wpdb->get_var( "SELECT comment_date_gmt FROM $wpdb->comments WHERE comment_approved = '1' ORDER BY comment_date_gmt DESC LIMIT 1" );
			break;
		case 'blog':
			$comment_modified_date = $wpdb->get_var( "SELECT comment_date FROM $wpdb->comments WHERE comment_approved = '1' ORDER BY comment_date_gmt DESC LIMIT 1" );
			break;
		case 'server':
			$add_seconds_server = gmdate( 'Z' );

$comment_modified_date = $wpdb->get_var( $wpdb->prepare( "SELECT DATE_ADD(comment_date_gmt, INTERVAL %s SECOND) FROM $wpdb->comments WHERE comment_approved = '1' ORDER BY comment_date_gmt DESC LIMIT 1", $add_seconds_server ) );
			break;
	}

if ( $comment_modified_date ) {
		wp_cache_set( $key, $comment_modified_date, 'timeinfo' );

return $comment_modified_date;
	}

return false;
}

/**
 * Retrieves the total comment counts for the whole site or a single post.
 *
 * @since 2.0.0
 *
 * @param int $post_id Optional. Restrict the comment counts to the given post. Default 0, which indicates that
 *                     comment counts for the whole site will be retrieved.
 * @return int[] {
 *     The number of comments keyed by their status.
 *
 *     @type int $approved            The number of approved comments.
 *     @type int $awaiting_moderation The number of comments awaiting moderation (a.k.a. pending).
 *     @type int $spam                The number of spam comments.
 *     @type int $trash               The number of trashed comments.
 *     @type int $post-trashed        The number of comments for posts that are in the trash.
 *     @type int $total_comments      The total number of non-trashed comments, including spam.
 *     @type int $all                 The total number of pending or approved comments.
 * }
 */
function get_comment_count( $post_id = 0 ) {
	$post_id = (int) $post_id;

$comment_count = array(
		'approved'            => 0,
		'awaiting_moderation' => 0,
		'spam'                => 0,
		'trash'               => 0,
		'post-trashed'        => 0,
		'total_comments'      => 0,
		'all'                 => 0,
	);

$args = array(
		'count'                     => true,
		'update_comment_meta_cache' => false,
		'orderby'                   => 'none',
	);
	if ( $post_id > 0 ) {
		$args['post_id'] = $post_id;
	}
	$mapping       = array(
		'approved'            => 'approve',
		'awaiting_moderation' => 'hold',
		'spam'                => 'spam',
		'trash'               => 'trash',
		'post-trashed'        => 'post-trashed',
	);
	$comment_count = array();
	foreach ( $mapping as $key => $value ) {
		$comment_count[ $key ] = get_comments( array_merge( $args, array( 'status' => $value ) ) );
	}

$comment_count['all']            = $comment_count['approved'] + $comment_count['awaiting_moderation'];
	$comment_count['total_comments'] = $comment_count['all'] + $comment_count['spam'];

return array_map( 'intval', $comment_count );
}

//
// Comment meta functions.
//

/**
 * Adds meta data field to a comment.
 *
 * @since 2.9.0
 *
 * @link https://developer.wordpress.org/reference/functions/add_comment_meta/
 *
 * @param int    $comment_id Comment ID.
 * @param string $meta_key   Metadata name.
 * @param mixed  $meta_value Metadata value. Must be serializable if non-scalar.
 * @param bool   $unique     Optional. Whether the same key should not be added.
 *                           Default false.
 * @return int|false Meta ID on success, false on failure.
 */
function add_comment_meta( $comment_id, $meta_key, $meta_value, $unique = false ) {
	return add_metadata( 'comment', $comment_id, $meta_key, $meta_value, $unique );
}

/**
 * Removes metadata matching criteria from a comment.
 *
 * You can match based on the key, or key and value. Removing based on key and
 * value, will keep from removing duplicate metadata with the same key. It also
 * allows removing all metadata matching key, if needed.
 *
 * @since 2.9.0
 *
 * @link https://developer.wordpress.org/reference/functions/delete_comment_meta/
 *
 * @param int    $comment_id Comment ID.
 * @param string $meta_key   Metadata name.
 * @param mixed  $meta_value Optional. Metadata value. If provided,
 *                           rows will only be removed that match the value.
 *                           Must be serializable if non-scalar. Default empty string.
 * @return bool True on success, false on failure.
 */
function delete_comment_meta( $comment_id, $meta_key, $meta_value = '' ) {
	return delete_metadata( 'comment', $comment_id, $meta_key, $meta_value );
}

/**
 * Retrieves comment meta field for a comment.
 *
 * @since 2.9.0
 *
 * @link https://developer.wordpress.org/reference/functions/get_comment_meta/
 *
 * @param int    $comment_id Comment ID.
 * @param string $key        Optional. The meta key to retrieve. By default,
 *                           returns data for all keys. Default empty string.
 * @param bool   $single     Optional. Whether to return a single value.
 *                           This parameter has no effect if `$key` is not specified.
 *                           Default false.
 * @return mixed An array of values if `$single` is false.
 *               The value of meta data field if `$single` is true.
 *               False for an invalid `$comment_id` (non-numeric, zero, or negative value).
 *               An empty string if a valid but non-existing comment ID is passed.
 */
function get_comment_meta( $comment_id, $key = '', $single = false ) {
	return get_metadata( 'comment', $comment_id, $key, $single );
}

/**
 * Queue comment meta for lazy-loading.
 *
 * @since 6.3.0
 *
 * @param array $comment_ids List of comment IDs.
 */
function wp_lazyload_comment_meta( array $comment_ids ) {
	if ( empty( $comment_ids ) ) {
		return;
	}
	$lazyloader = wp_metadata_lazyloader();
	$lazyloader->queue_objects( 'comment', $comment_ids );
}

/**
 * Updates comment meta field based on comment ID.
 *
 * Use the $prev_value parameter to differentiate between meta fields with the
 * same key and comment ID.
 *
 * If the meta field for the comment does not exist, it will be added.
 *
 * @since 2.9.0
 *
 * @link https://developer.wordpress.org/reference/functions/update_comment_meta/
 *
 * @param int    $comment_id Comment ID.
 * @param string $meta_key   Metadata key.
 * @param mixed  $meta_value Metadata value. Must be serializable if non-scalar.
 * @param mixed  $prev_value Optional. Previous value to check before updating.
 *                           If specified, only update existing metadata entries with
 *                           this value. Otherwise, update all entries. Default empty string.
 * @return int|bool Meta ID if the key didn't exist, true on successful update,
 *                  false on failure or if the value passed to the function
 *                  is the same as the one that is already in the database.
 */
function update_comment_meta( $comment_id, $meta_key, $meta_value, $prev_value = '' ) {
	return update_metadata( 'comment', $comment_id, $meta_key, $meta_value, $prev_value );
}

/**
 * Sets the cookies used to store an unauthenticated commentator's identity. Typically used
 * to recall previous comments by this commentator that are still held in moderation.
 *
 * @since 3.4.0
 * @since 4.9.6 The `$cookies_consent` parameter was added.
 *
 * @param WP_Comment $comment         Comment object.
 * @param WP_User    $user            Comment author's user object. The user may not exist.
 * @param bool       $cookies_consent Optional. Comment author's consent to store cookies. Default true.
 */
function wp_set_comment_cookies( $comment, $user, $cookies_consent = true ) {
	// If the user already exists, or the user opted out of cookies, don't set cookies.
	if ( $user->exists() ) {
		return;
	}

if ( false === $cookies_consent ) {
		// Remove any existing cookies.
		$past = time() - YEAR_IN_SECONDS;
		setcookie( 'comment_author_' . COOKIEHASH, ' ', $past, COOKIEPATH, COOKIE_DOMAIN );
		setcookie( 'comment_author_email_' . COOKIEHASH, ' ', $past, COOKIEPATH, COOKIE_DOMAIN );
		setcookie( 'comment_author_url_' . COOKIEHASH, ' ', $past, COOKIEPATH, COOKIE_DOMAIN );

return;
	}

/**
	 * Filters the lifetime of the comment cookie in seconds.
	 *
	 * @since 2.8.0
	 *
	 * @param int $seconds Comment cookie lifetime. Default 30000000.
	 */
	$comment_cookie_lifetime = time() + apply_filters( 'comment_cookie_lifetime', 30000000 );

$secure = ( 'https' === parse_url( home_url(), PHP_URL_SCHEME ) );

setcookie( 'comment_author_' . COOKIEHASH, $comment->comment_author, $comment_cookie_lifetime, COOKIEPATH, COOKIE_DOMAIN, $secure );
	setcookie( 'comment_author_email_' . COOKIEHASH, $comment->comment_author_email, $comment_cookie_lifetime, COOKIEPATH, COOKIE_DOMAIN, $secure );
	setcookie( 'comment_author_url_' . COOKIEHASH, esc_url( $comment->comment_author_url ), $comment_cookie_lifetime, COOKIEPATH, COOKIE_DOMAIN, $secure );
}

/**
 * Sanitizes the cookies sent to the user already.
 *
 * Will only do anything if the cookies have already been created for the user.
 * Mostly used after cookies had been sent to use elsewhere.
 *
 * @since 2.0.4
 */
function sanitize_comment_cookies() {
	if ( isset( $_COOKIE[ 'comment_author_' . COOKIEHASH ] ) ) {
		/**
		 * Filters the comment author's name cookie before it is set.
		 *
		 * When this filter hook is evaluated in wp_filter_comment(),
		 * the comment author's name string is passed.
		 *
		 * @since 1.5.0
		 *
		 * @param string $author_cookie The comment author name cookie.
		 */
		$comment_author = apply_filters( 'pre_comment_author_name', $_COOKIE[ 'comment_author_' . COOKIEHASH ] );
		$comment_author = wp_unslash( $comment_author );
		$comment_author = esc_attr( $comment_author );

$_COOKIE[ 'comment_author_' . COOKIEHASH ] = $comment_author;
	}

if ( isset( $_COOKIE[ 'comment_author_email_' . COOKIEHASH ] ) ) {
		/**
		 * Filters the comment author's email cookie before it is set.
		 *
		 * When this filter hook is evaluated in wp_filter_comment(),
		 * the comment author's email string is passed.
		 *
		 * @since 1.5.0
		 *
		 * @param string $author_email_cookie The comment author email cookie.
		 */
		$comment_author_email = apply_filters( 'pre_comment_author_email', $_COOKIE[ 'comment_author_email_' . COOKIEHASH ] );
		$comment_author_email = wp_unslash( $comment_author_email );
		$comment_author_email = esc_attr( $comment_author_email );

$_COOKIE[ 'comment_author_email_' . COOKIEHASH ] = $comment_author_email;
	}

if ( isset( $_COOKIE[ 'comment_author_url_' . COOKIEHASH ] ) ) {
		/**
		 * Filters the comment author's URL cookie before it is set.
		 *
		 * When this filter hook is evaluated in wp_filter_comment(),
		 * the comment author's URL string is passed.
		 *
		 * @since 1.5.0
		 *
		 * @param string $author_url_cookie The comment author URL cookie.
		 */
		$comment_author_url = apply_filters( 'pre_comment_author_url', $_COOKIE[ 'comment_author_url_' . COOKIEHASH ] );
		$comment_author_url = wp_unslash( $comment_author_url );

$_COOKIE[ 'comment_author_url_' . COOKIEHASH ] = $comment_author_url;
	}
}

/**
 * Validates whether this comment is allowed to be made.
 *
 * @since 2.0.0
 * @since 4.7.0 The `$avoid_die` parameter was added, allowing the function
 *              to return a WP_Error object instead of dying.
 * @since 5.5.0 The `$avoid_die` parameter was renamed to `$wp_error`.
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param array $commentdata Contains information on the comment.
 * @param bool  $wp_error    When true, a disallowed comment will result in the function
 *                           returning a WP_Error object, rather than executing wp_die().
 *                           Default false.
 * @return int|string|WP_Error Allowed comments return the approval status (0|1|'spam'|'trash').
 *                             If `$wp_error` is true, disallowed comments return a WP_Error.
 */
function wp_allow_comment( $commentdata, $wp_error = false ) {
	global $wpdb;

/*
	 * Simple duplicate check.
	 * expected_slashed ($comment_post_ID, $comment_author, $comment_author_email, $comment_content)
	 */
	$dupe = $wpdb->prepare(
		"SELECT comment_ID FROM $wpdb->comments WHERE comment_post_ID = %d AND comment_parent = %s AND comment_approved != 'trash' AND ( comment_author = %s ",
		wp_unslash( $commentdata['comment_post_ID'] ),
		wp_unslash( $commentdata['comment_parent'] ),
		wp_unslash( $commentdata['comment_author'] )
	);
	if ( $commentdata['comment_author_email'] ) {
		$dupe .= $wpdb->prepare(
			'AND comment_author_email = %s ',
			wp_unslash( $commentdata['comment_author_email'] )
		);
	}
	$dupe .= $wpdb->prepare(
		') AND comment_content = %s LIMIT 1',
		wp_unslash( $commentdata['comment_content'] )
	);

$dupe_id = $wpdb->get_var( $dupe );

/**
	 * Filters the ID, if any, of the duplicate comment found when creating a new comment.
	 *
	 * Return an empty value from this filter to allow what WP considers a duplicate comment.
	 *
	 * @since 4.4.0
	 *
	 * @param int   $dupe_id     ID of the comment identified as a duplicate.
	 * @param array $commentdata Data for the comment being created.
	 */
	$dupe_id = apply_filters( 'duplicate_comment_id', $dupe_id, $commentdata );

if ( $dupe_id ) {
		/**
		 * Fires immediately after a duplicate comment is detected.
		 *
		 * @since 3.0.0
		 *
		 * @param array $commentdata Comment data.
		 */
		do_action( 'comment_duplicate_trigger', $commentdata );

/**
		 * Filters duplicate comment error message.
		 *
		 * @since 5.2.0
		 *
		 * @param string $comment_duplicate_message Duplicate comment error message.
		 */
		$comment_duplicate_message = apply_filters( 'comment_duplicate_message', __( 'Duplicate comment detected; it looks as though you&#8217;ve already said that!' ) );

if ( $wp_error ) {
			return new WP_Error( 'comment_duplicate', $comment_duplicate_message, 409 );
		} else {
			if ( wp_doing_ajax() ) {
				die( $comment_dupl