/wp-includes/comment.php

<?php
/**
 * Manages WordPress comments
 *
 * @package WordPress
 * @subpackage Comment
 */

/**
 * Check 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 whitelist, 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 match the blacklist of words,
 * then the check fails.
 *
 * If the comment author was approved before, then the comment is automatically
 * whitelisted.
 *
 * 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 );

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

		/**
		 * Filter the maximum number of links allowed in a comment.
		 *
		 * @since 3.0.0
		 *
		 * @param int    $num_links The number of links allowed.
		 * @param string $url       Comment author's URL. Included in allowed links total.
		 */
		$num_links = apply_filters( 'comment_max_links_url', $num_links, $url );

		/*
		 * 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#i";
			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_whitelist')) {
		if ( 'trackback' != $comment_type && 'pingback' != $comment_type && $author != '' && $email != '' ) {
			// expected_slashed ($author, $email)
			$ok_to_comment = $wpdb->get_var("SELECT comment_approved FROM $wpdb->comments WHERE comment_author = '$author' AND comment_author_email = '$email' and comment_approved = '1' LIMIT 1");
			if ( ( 1 == $ok_to_comment ) &&
				( empty($mod_keys) || false === strpos( $email, $mod_keys) ) )
					return true;
			else
				return false;
		} else {
			return false;
		}
	}
	return true;
}

/**
 * Retrieve the approved comments for post $post_id.
 *
 * @since 2.0.0
 * @since 4.1.0 Refactored to leverage {@see WP_Comment_Query} over a direct query.
 *
 * @param  int   $post_id The ID of the post.
 * @param  array $args    Optional. See {@see WP_Comment_Query::query()} for information
 *                        on accepted arguments.
 * @return int|array $comments The approved comments, or number of comments if `$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',
	);
	$r = wp_parse_args( $args, $defaults );

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

/**
 * 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 wpdb $wpdb WordPress database abstraction object.
 *
 * @param object|string|int $comment Comment to retrieve.
 * @param string $output Optional. OBJECT or ARRAY_A or ARRAY_N constants.
 * @return object|array|null Depends on $output value.
 */
function get_comment(&$comment, $output = OBJECT) {
	global $wpdb;

	if ( empty($comment) ) {
		if ( isset($GLOBALS['comment']) )
			$_comment = & $GLOBALS['comment'];
		else
			$_comment = null;
	} elseif ( is_object($comment) ) {
		wp_cache_add($comment->comment_ID, $comment, 'comment');
		$_comment = $comment;
	} else {
		if ( isset($GLOBALS['comment']) && ($GLOBALS['comment']->comment_ID == $comment) ) {
			$_comment = & $GLOBALS['comment'];
		} elseif ( ! $_comment = wp_cache_get($comment, 'comment') ) {
			$_comment = $wpdb->get_row($wpdb->prepare("SELECT * FROM $wpdb->comments WHERE comment_ID = %d LIMIT 1", $comment));
			if ( ! $_comment )
				return null;
			wp_cache_add($_comment->comment_ID, $_comment, 'comment');
		}
	}

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

	if ( $output == OBJECT ) {
		return $_comment;
	} elseif ( $output == ARRAY_A ) {
		$__comment = get_object_vars($_comment);
		return $__comment;
	} elseif ( $output == ARRAY_N ) {
		$__comment = array_values(get_object_vars($_comment));
		return $__comment;
	} else {
		return $_comment;
	}
}

/**
 * Retrieve 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 $args Optional. Array or string of arguments. See {@see WP_Comment_Query::parse_query()}
 *                           for information on accepted arguments. Default empty.
 * @return int|array List of comments or number of found comments if `$count` argument is true.
 */
function get_comments( $args = '' ) {
	$query = new WP_Comment_Query;
	return $query->query( $args );
}

/**
 * WordPress Comment Query class.
 *
 * See WP_Comment_Query::__construct() for accepted arguments.
 *
 * @since 3.1.0
 */
class WP_Comment_Query {
	/**
	 * SQL for database query.
	 *
	 * @since 4.0.1
	 * @access public
	 * @var string
	 */
	public $request;

	/**
	 * Metadata query container
	 *
	 * @since 3.5.0
	 * @access public
	 * @var object WP_Meta_Query
	 */
	public $meta_query = false;

	/**
	 * Date query container
	 *
	 * @since 3.7.0
	 * @access public
	 * @var object WP_Date_Query
	 */
	public $date_query = false;

	/**
	 * Query vars set by the user.
	 *
	 * @since 3.1.0
	 * @access public
	 * @var array
	 */
	public $query_vars;

	/**
	 * Default values for query vars.
	 *
	 * @since 4.2.0
	 * @access public
	 * @var array
	 */
	public $query_var_defaults;

	/**
	 * List of comments located by the query.
	 *
	 * @since 4.0.0
	 * @access public
	 * @var array
	 */
	public $comments;

	/**
	 * Make private/protected methods readable for backwards compatibility.
	 *
	 * @since 4.0.0
	 * @access public
	 *
	 * @param callable $name      Method to call.
	 * @param array    $arguments Arguments to pass when calling.
	 * @return mixed|bool Return value of the callback, false otherwise.
	 */
	public function __call( $name, $arguments ) {
		if ( 'get_search_sql' === $name ) {
			return call_user_func_array( array( $this, $name ), $arguments );
		}
		return false;
	}

	/**
	 * Constructor.
	 *
	 * Sets up the comment query, based on the query vars passed.
	 *
	 * @since  4.2.0
	 * @access public
	 *
	 * @param string|array $query {
	 *     Optional. Array or query string of comment query parameters. Default empty.
	 *
	 *     @type string       $author_email        Comment author email address. Default empty.
	 *     @type array        $author__in          Array of author IDs to include comments for. Default empty.
	 *     @type array        $author__not_in      Array of author IDs to exclude comments for. Default empty.
	 *     @type array        $comment__in         Array of comment IDs to include. Default empty.
	 *     @type array        $comment__not_in     Array of comment IDs to exclude. Default empty.
	 *     @type bool         $count               Whether to return a comment count (true) or array of comment
	 *                                             objects (false). Default false.
	 *     @type array        $date_query          Date query clauses to limit comments by. See WP_Date_Query.
	 *                                             Default null.
	 *     @type string       $fields              Comment fields to return. Accepts 'ids' for comment IDs only or
	 *                                             empty for all fields. Default empty.
	 *     @type int          $ID                  Currently unused.
	 *     @type array        $include_unapproved  Array of IDs or email addresses of users whose unapproved comments
	 *                                             will be returned by the query regardless of `$status`. Default empty.
	 *     @type int          $karma               Karma score to retrieve matching comments for. Default empty.
	 *     @type string       $meta_key            Include comments with a matching comment meta key. Default empty.
	 *     @type string       $meta_value          Include comments with a matching comment meta value. Requires
	 *                                             `$meta_key` to be set. Default empty.
	 *     @type array        $meta_query          Meta query clauses to limit retrieved comments by.
	 *                                             See WP_Meta_Query. Default empty.
	 *     @type int          $number              Maximum number of comments to retrieve. Default null (no limit).
	 *     @type int          $offset              Number of comments to offset the query. Used to build LIMIT clause.
	 *                                             Default 0.
	 *     @type string|array $orderby             Comment status or array of statuses. To use 'meta_value' or
	 *                                             'meta_value_num', `$meta_key` must also be defined. To sort by
	 *                                             a specific `$meta_query` clause, use that clause's array key.
	 *                                             Accepts 'comment_agent', 'comment_approved', 'comment_author',
	 *                                             'comment_author_email', 'comment_author_IP',
	 *                                             'comment_author_url', 'comment_content', 'comment_date',
	 *                                             'comment_date_gmt', 'comment_ID', 'comment_karma',
	 *                                             'comment_parent', 'comment_post_ID', 'comment_type', 'user_id',
	 *                                             'meta_value', 'meta_value_num', the value of $meta_key, and the
	 *                                             array keys of `$meta_query`. Also accepts false, an empty array,
	 *                                             or 'none' to disable `ORDER BY` clause.
	 *                                             Default: 'comment_date_gmt'.
	 *     @type string       $order               How to order retrieved comments. Accepts 'ASC', 'DESC'.
	 *                                             Default: 'DESC'.
	 *     @type int          $parent              Parent ID of comment to retrieve children of. Default empty.
	 *     @type array        $post_author__in     Array of author IDs to retrieve comments for. Default empty.
	 *     @type array        $post_author__not_in Array of author IDs *not* to retrieve comments for. Default empty.
	 *     @type int          $post_ID             Currently unused.
	 *     @type int          $post_id             Limit results to those affiliated with a given post ID. Default 0.
	 *     @type array        $post__in            Array of post IDs to include affiliated comments for. Default empty.
	 *     @type array        $post__not_in        Array of post IDs to exclude affiliated comments for. Default empty.
	 *     @type int          $post_author         Comment author ID to limit results by. Default empty.
	 *     @type string       $post_status         Post status to retrieve affiliated comments for. Default empty.
	 *     @type string       $post_type           Post type to retrieve affiliated comments for. Default empty.
	 *     @type string       $post_name           Post name to retrieve affiliated comments for. Default empty.
	 *     @type int          $post_parent         Post parent ID to retrieve affiliated comments for. Default empty.
	 *     @type string       $search              Search term(s) to retrieve matching comments for. Default empty.
	 *     @type string       $status              Comment status to limit results by. Accepts 'hold'
	 *                                             (`comment_status=0`), 'approve' (`comment_status=1`), 'all', or a
	 *                                             custom comment status. Default 'all'.
	 *     @type string|array $type                Include comments of a given type, or array of types. Accepts
	 *                                             'comment', 'pings' (includes 'pingback' and 'trackback'), or any
	 *                                             custom type string. Default empty.
	 *     @type array        $type__in            Include comments from a given array of comment types. Default empty.
	 *     @type array        $type__not_in        Exclude comments from a given array of comment types. Default empty.
	 *     @type int          $user_id             Include comments for a specific user ID. Default empty.
	 * }
	 * @return WP_Comment_Query WP_Comment_Query instance.
	 */
	public function __construct( $query = '' ) {
		$this->query_var_defaults = array(
			'author_email' => '',
			'author__in' => '',
			'author__not_in' => '',
			'include_unapproved' => '',
			'fields' => '',
			'ID' => '',
			'comment__in' => '',
			'comment__not_in' => '',
			'karma' => '',
			'number' => '',
			'offset' => '',
			'orderby' => '',
			'order' => 'DESC',
			'parent' => '',
			'post_author__in' => '',
			'post_author__not_in' => '',
			'post_ID' => '',
			'post_id' => 0,
			'post__in' => '',
			'post__not_in' => '',
			'post_author' => '',
			'post_name' => '',
			'post_parent' => '',
			'post_status' => '',
			'post_type' => '',
			'status' => 'all',
			'type' => '',
			'type__in' => '',
			'type__not_in' => '',
			'user_id' => '',
			'search' => '',
			'count' => false,
			'meta_key' => '',
			'meta_value' => '',
			'meta_query' => '',
			'date_query' => null, // See WP_Date_Query
		);

		if ( ! empty( $query ) ) {
			$this->query( $query );
		}
	}

	/**
	 * Parse arguments passed to the comment query with default query parameters.
	 *
	 * @since  4.2.0 Extracted from WP_Comment_Query::query().
	 *
	 * @access public
	 *
	 * @param string|array $query WP_Comment_Query arguments. See WP_Comment_Query::__construct()
	 */
	public function parse_query( $query = '' ) {
		if ( empty( $query ) ) {
			$query = $this->query_vars;
		}

		$this->query_vars = wp_parse_args( $query, $this->query_var_defaults );
		do_action_ref_array( 'parse_comment_query', array( &$this ) );
	}

	/**
	 * Sets up the WordPress query for retrieving comments.
	 *
	 * @since 3.1.0
	 * @since 4.1.0 Introduced 'comment__in', 'comment__not_in', 'post_author__in',
	 *              'post_author__not_in', 'author__in', 'author__not_in', 'post__in',
	 *              'post__not_in', 'include_unapproved', 'type__in', and 'type__not_in'
	 *              arguments to $query_vars.
	 * @since 4.2.0 Moved parsing to WP_Comment_Query::parse_query().
	 * @access public
	 *
	 * @param string|array $query Array or URL query string of parameters.
	 * @return array List of comments.
	 */
	public function query( $query ) {
		$this->query_vars = wp_parse_args( $query );
		return $this->get_comments();
	}

	/**
	 * Get a list of comments matching the query vars.
	 *
	 * @since 4.2.0
	 * @access public
	 *
	 * @global wpdb $wpdb WordPress database abstraction object.
	 *
	 * @return array The list of comments.
	 */
	public function get_comments() {
		global $wpdb;

		$groupby = '';

		$this->parse_query();

		// Parse meta query
		$this->meta_query = new WP_Meta_Query();
		$this->meta_query->parse_query_vars( $this->query_vars );

		if ( ! empty( $this->meta_query->queries ) ) {
			$meta_query_clauses = $this->meta_query->get_sql( 'comment', $wpdb->comments, 'comment_ID', $this );
		}

		/**
		 * Fires before comments are retrieved.
		 *
		 * @since 3.1.0
		 *
		 * @param WP_Comment_Query &$this Current instance of WP_Comment_Query, passed by reference.
		 */
		do_action_ref_array( 'pre_get_comments', array( &$this ) );

		// $args can include anything. Only use the args defined in the query_var_defaults to compute the key.
		$key = md5( serialize( wp_array_slice_assoc( $this->query_vars, array_keys( $this->query_var_defaults ) ) ) );
		$last_changed = wp_cache_get( 'last_changed', 'comment' );
		if ( ! $last_changed ) {
			$last_changed = microtime();
			wp_cache_set( 'last_changed', $last_changed, 'comment' );
		}
		$cache_key = "get_comments:$key:$last_changed";

		if ( $cache = wp_cache_get( $cache_key, 'comment' ) ) {
			$this->comments = $cache;
			return $this->comments;
		}

		$where = array();

		// Assemble clauses related to 'comment_approved'.
		$approved_clauses = array();

		// 'status' accepts an array or a comma-separated string.
		$status_clauses = array();
		$statuses = $this->query_vars['status'];
		if ( ! is_array( $statuses ) ) {
			$statuses = preg_split( '/[\s,]+/', $statuses );
		}

		// 'any' overrides other statuses.
		if ( ! in_array( 'any', $statuses ) ) {
			foreach ( $statuses as $status ) {
				switch ( $status ) {
					case 'hold' :
						$status_clauses[] = "comment_approved = '0'";
						break;

					case 'approve' :
						$status_clauses[] = "comment_approved = '1'";
						break;

					case 'all' :
					case '' :
						$status_clauses[] = "( comment_approved = '0' OR comment_approved = '1' )";
						break;

					default :
						$status_clauses[] = $wpdb->prepare( "comment_approved = %s", $status );
						break;
				}
			}

			if ( ! empty( $status_clauses ) ) {
				$approved_clauses[] = '( ' . implode( ' OR ', $status_clauses ) . ' )';
			}
		}

		// User IDs or emails whose unapproved comments are included, regardless of $status.
		if ( ! empty( $this->query_vars['include_unapproved'] ) ) {
			$include_unapproved = $this->query_vars['include_unapproved'];

			// Accepts arrays or comma-separated strings.
			if ( ! is_array( $include_unapproved ) ) {
				$include_unapproved = preg_split( '/[\s,]+/', $include_unapproved );
			}

			$unapproved_ids = $unapproved_emails = array();
			foreach ( $include_unapproved as $unapproved_identifier ) {
				// Numeric values are assumed to be user ids.
				if ( is_numeric( $unapproved_identifier ) ) {
					$approved_clauses[] = $wpdb->prepare( "( user_id = %d AND comment_approved = '0' )", $unapproved_identifier );

				// Otherwise we match against email addresses.
				} else {
					$approved_clauses[] = $wpdb->prepare( "( comment_author_email = %s AND comment_approved = '0' )", $unapproved_identifier );
				}
			}
		}

		// Collapse comment_approved clauses into a single OR-separated clause.
		if ( ! empty( $approved_clauses ) ) {
			if ( 1 === count( $approved_clauses ) ) {
				$where[] = $approved_clauses[0];
			} else {
				$where[] = '( ' . implode( ' OR ', $approved_clauses ) . ' )';
			}
		}

		$order = ( 'ASC' == strtoupper( $this->query_vars['order'] ) ) ? 'ASC' : 'DESC';

		// Disable ORDER BY with 'none', an empty array, or boolean false.
		if ( in_array( $this->query_vars['orderby'], array( 'none', array(), false ), true ) ) {
			$orderby = '';
		} elseif ( ! empty( $this->query_vars['orderby'] ) ) {
			$ordersby = is_array( $this->query_vars['orderby'] ) ?
				$this->query_vars['orderby'] :
				preg_split( '/[,\s]/', $this->query_vars['orderby'] );

			$orderby_array = array();
			$found_orderby_comment_ID = false;
			foreach ( $ordersby as $_key => $_value ) {
				if ( ! $_value ) {
					continue;
				}

				if ( is_int( $_key ) ) {
					$_orderby = $_value;
					$_order = $order;
				} else {
					$_orderby = $_key;
					$_order = $_value;
				}

				if ( ! $found_orderby_comment_ID && 'comment_ID' === $_orderby ) {
					$found_orderby_comment_ID = true;
				}

				$parsed = $this->parse_orderby( $_orderby );

				if ( ! $parsed ) {
					continue;
				}

				$orderby_array[] = $parsed . ' ' . $this->parse_order( $_order );
			}

			// If no valid clauses were found, order by comment_date_gmt.
			if ( empty( $orderby_array ) ) {
				$orderby_array[] = "$wpdb->comments.comment_date_gmt $order";
			}

			// To ensure determinate sorting, always include a comment_ID clause.
			if ( ! $found_orderby_comment_ID ) {
				$comment_ID_order = '';

				// Inherit order from comment_date or comment_date_gmt, if available.
				foreach ( $orderby_array as $orderby_clause ) {
					if ( preg_match( '/comment_date(?:_gmt)*\ (ASC|DESC)/', $orderby_clause, $match ) ) {
						$comment_ID_order = $match[1];
						break;
					}
				}

				// If no date-related order is available, use the date from the first available clause.
				if ( ! $comment_ID_order ) {
					foreach ( $orderby_array as $orderby_clause ) {
						if ( false !== strpos( 'ASC', $orderby_clause ) ) {
							$comment_ID_order = 'ASC';
						} else {
							$comment_ID_order = 'DESC';
						}

						break;
					}
				}

				// Default to DESC.
				if ( ! $comment_ID_order ) {
					$comment_ID_order = 'DESC';
				}

				$orderby_array[] = "$wpdb->comments.comment_ID $comment_ID_order";
			}

			$orderby = implode( ', ', $orderby_array );
		} else {
			$orderby = "$wpdb->comments.comment_date_gmt $order";
		}

		$number = absint( $this->query_vars['number'] );
		$offset = absint( $this->query_vars['offset'] );

		if ( ! empty( $number ) ) {
			if ( $offset ) {
				$limits = 'LIMIT ' . $offset . ',' . $number;
			} else {
				$limits = 'LIMIT ' . $number;
			}
		} else {
			$limits = '';
		}

		if ( $this->query_vars['count'] ) {
			$fields = 'COUNT(*)';
		} else {
			switch ( strtolower( $this->query_vars['fields'] ) ) {
				case 'ids':
					$fields = "$wpdb->comments.comment_ID";
					break;
				default:
					$fields = "*";
					break;
			}
		}

		$join = '';

		$post_id = absint( $this->query_vars['post_id'] );
		if ( ! empty( $post_id ) ) {
			$where[] = $wpdb->prepare( 'comment_post_ID = %d', $post_id );
		}

		// Parse comment IDs for an IN clause.
		if ( ! empty( $this->query_vars['comment__in'] ) ) {
			$where[] = 'comment_ID IN ( ' . implode( ',', wp_parse_id_list( $this->query_vars['comment__in'] ) ) . ' )';
		}

		// Parse comment IDs for a NOT IN clause.
		if ( ! empty( $this->query_vars['comment__not_in'] ) ) {
			$where[] = 'comment_ID NOT IN ( ' . implode( ',', wp_parse_id_list( $this->query_vars['comment__not_in'] ) ) . ' )';
		}

		// Parse comment post IDs for an IN clause.
		if ( ! empty( $this->query_vars['post__in'] ) ) {
			$where[] = 'comment_post_ID IN ( ' . implode( ',', wp_parse_id_list( $this->query_vars['post__in'] ) ) . ' )';
		}

		// Parse comment post IDs for a NOT IN clause.
		if ( ! empty( $this->query_vars['post__not_in'] ) ) {
			$where[] = 'comment_post_ID NOT IN ( ' . implode( ',', wp_parse_id_list( $this->query_vars['post__not_in'] ) ) . ' )';
		}

		if ( '' !== $this->query_vars['author_email'] ) {
			$where[] = $wpdb->prepare( 'comment_author_email = %s', $this->query_vars['author_email'] );
		}

		if ( '' !== $this->query_vars['karma'] ) {
			$where[] = $wpdb->prepare( 'comment_karma = %d', $this->query_vars['karma'] );
		}

		// Filtering by comment_type: 'type', 'type__in', 'type__not_in'.
		$raw_types = array(
			'IN' => array_merge( (array) $this->query_vars['type'], (array) $this->query_vars['type__in'] ),
			'NOT IN' => (array) $this->query_vars['type__not_in'],
		);

		$comment_types = array();
		foreach ( $raw_types as $operator => $_raw_types ) {
			$_raw_types = array_unique( $_raw_types );

			foreach ( $_raw_types as $type ) {
				switch ( $type ) {
					// An empty translates to 'all', for backward compatibility
					case '':
					case 'all' :
						break;

					case 'comment':
					case 'comments':
						$comment_types[ $operator ][] = "''";
						break;

					case 'pings':
						$comment_types[ $operator ][] = "'pingback'";
						$comment_types[ $operator ][] = "'trackback'";
						break;

					default:
						$comment_types[ $operator ][] = $wpdb->prepare( '%s', $type );
						break;
				}
			}

			if ( ! empty( $comment_types[ $operator ] ) ) {
				$types_sql = implode( ', ', $comment_types[ $operator ] );
				$where[] = "comment_type $operator ($types_sql)";
			}
		}

		if ( '' !== $this->query_vars['parent'] ) {
			$where[] = $wpdb->prepare( 'comment_parent = %d', $this->query_vars['parent'] );
		}

		if ( is_array( $this->query_vars['user_id'] ) ) {
			$where[] = 'user_id IN (' . implode( ',', array_map( 'absint', $this->query_vars['user_id'] ) ) . ')';
		} elseif ( '' !== $this->query_vars['user_id'] ) {
			$where[] = $wpdb->prepare( 'user_id = %d', $this->query_vars['user_id'] );
		}

		if ( '' !== $this->query_vars['search'] ) {
			$search_sql = $this->get_search_sql(
				$this->query_vars['search'],
				array( 'comment_author', 'comment_author_email', 'comment_author_url', 'comment_author_IP', 'comment_content' )
			);

			// Strip leading 'AND'.
			$where[] = preg_replace( '/^\s*AND\s*/', '', $search_sql );
		}

		// If any post-related query vars are passed, join the posts table.
		$join_posts_table = false;
		$plucked = wp_array_slice_assoc( $this->query_vars, array( 'post_author', 'post_name', 'post_parent', 'post_status', 'post_type' ) );
		$post_fields = array_filter( $plucked );

		if ( ! empty( $post_fields ) ) {
			$join_posts_table = true;
			foreach ( $post_fields as $field_name => $field_value ) {
				// $field_value may be an array.
				$esses = array_fill( 0, count( (array) $field_value ), '%s' );
				$where[] = $wpdb->prepare( " {$wpdb->posts}.{$field_name} IN (" . implode( ',', $esses ) . ')', $field_value );
			}
		}

		// Comment author IDs for an IN clause.
		if ( ! empty( $this->query_vars['author__in'] ) ) {
			$where[] = 'user_id IN ( ' . implode( ',', wp_parse_id_list( $this->query_vars['author__in'] ) ) . ' )';
		}

		// Comment author IDs for a NOT IN clause.
		if ( ! empty( $this->query_vars['author__not_in'] ) ) {
			$where[] = 'user_id NOT IN ( ' . implode( ',', wp_parse_id_list( $this->query_vars['author__not_in'] ) ) . ' )';
		}

		// Post author IDs for an IN clause.
		if ( ! empty( $this->query_vars['post_author__in'] ) ) {
			$join_posts_table = true;
			$where[] = 'post_author IN ( ' . implode( ',', wp_parse_id_list( $this->query_vars['post_author__in'] ) ) . ' )';
		}

		// Post author IDs for a NOT IN clause.
		if ( ! empty( $this->query_vars['post_author__not_in'] ) ) {
			$join_posts_table = true;
			$where[] = 'post_author NOT IN ( ' . implode( ',', wp_parse_id_list( $this->query_vars['post_author__not_in'] ) ) . ' )';
		}

		if ( $join_posts_table ) {
			$join = "JOIN $wpdb->posts ON $wpdb->posts.ID = $wpdb->comments.comment_post_ID";
		}

		if ( ! empty( $meta_query_clauses ) ) {
			$join .= $meta_query_clauses['join'];

			// Strip leading 'AND'.
			$where[] = preg_replace( '/^\s*AND\s*/', '', $meta_query_clauses['where'] );

			if ( ! $this->query_vars['count'] ) {
				$groupby = "{$wpdb->comments}.comment_ID";
			}
		}

		$date_query = $this->query_vars['date_query'];
		if ( ! empty( $date_query ) && is_array( $date_query ) ) {
			$date_query_object = new WP_Date_Query( $date_query, 'comment_date' );
			$where[] = preg_replace( '/^\s*AND\s*/', '', $date_query_object->get_sql() );
		}

		$where = implode( ' AND ', $where );

		$pieces = array( 'fields', 'join', 'where', 'orderby', 'limits', 'groupby' );
		/**
		 * Filter the comment query clauses.
		 *
		 * @since 3.1.0
		 *
		 * @param array            $pieces A compacted array of comment query clauses.
		 * @param WP_Comment_Query &$this  Current instance of WP_Comment_Query, passed by reference.
		 */
		$clauses = apply_filters_ref_array( 'comments_clauses', array( compact( $pieces ), &$this ) );

		$fields = isset( $clauses[ 'fields' ] ) ? $clauses[ 'fields' ] : '';
		$join = isset( $clauses[ 'join' ] ) ? $clauses[ 'join' ] : '';
		$where = isset( $clauses[ 'where' ] ) ? $clauses[ 'where' ] : '';
		$orderby = isset( $clauses[ 'orderby' ] ) ? $clauses[ 'orderby' ] : '';
		$limits = isset( $clauses[ 'limits' ] ) ? $clauses[ 'limits' ] : '';
		$groupby = isset( $clauses[ 'groupby' ] ) ? $clauses[ 'groupby' ] : '';

		if ( $where ) {
			$where = 'WHERE ' . $where;
		}

		if ( $groupby ) {
			$groupby = 'GROUP BY ' . $groupby;
		}

		if ( $orderby ) {
			$orderby = "ORDER BY $orderby";
		}

		$this->request = "SELECT $fields FROM $wpdb->comments $join $where $groupby $orderby $limits";

		if ( $this->query_vars['count'] ) {
			return $wpdb->get_var( $this->request );
		}

		if ( 'ids' == $this->query_vars['fields'] ) {
			$this->comments = $wpdb->get_col( $this->request );
			return array_map( 'intval', $this->comments );
		}

		$results = $wpdb->get_results( $this->request );
		/**
		 * Filter the comment query results.
		 *
		 * @since 3.1.0
		 *
		 * @param array            $results  An array of comments.
		 * @param WP_Comment_Query &$this    Current instance of WP_Comment_Query, passed by reference.
		 */
		$comments = apply_filters_ref_array( 'the_comments', array( $results, &$this ) );

		wp_cache_add( $cache_key, $comments, 'comment' );

		$this->comments = $comments;
		return $this->comments;
	}

	/**
	 * Used internally to generate an SQL string for searching across multiple columns
	 *
	 * @access protected
	 * @since 3.1.0
	 *
	 * @param string $string
	 * @param array $cols
	 * @return string
	 */
	protected function get_search_sql( $string, $cols ) {
		global $wpdb;

		$like = '%' . $wpdb->esc_like( $string ) . '%';

		$searches = array();
		foreach ( $cols as $col ) {
			$searches[] = $wpdb->prepare( "$col LIKE %s", $like );
		}

		return ' AND (' . implode(' OR ', $searches) . ')';
	}

	/**
	 * Parse and sanitize 'orderby' keys passed to the comment query.
	 *
	 * @since 4.2.0
	 * @access protected
	 *
	 * @global wpdb $wpdb WordPress database abstraction object.
	 *
	 * @param string $orderby Alias for the field to order by.
	 * @return string|bool Value to used in the ORDER clause. False otherwise.
	 */
	protected function parse_orderby( $orderby ) {
		global $wpdb;

		$allowed_keys = array(
			'comment_agent',
			'comment_approved',
			'comment_author',
			'comment_author_email',
			'comment_author_IP',
			'comment_author_url',
			'comment_content',
			'comment_date',
			'comment_date_gmt',
			'comment_ID',
			'comment_karma',
			'comment_parent',
			'comment_post_ID',
			'comment_type',
			'user_id',
		);

		if ( ! empty( $this->query_vars['meta_key'] ) ) {
			$allowed_keys[] = $this->query_vars['meta_key'];
			$allowed_keys[] = 'meta_value';
			$allowed_keys[] = 'meta_value_num';
		}

		$meta_query_clauses = $this->meta_query->get_clauses();
		if ( $meta_query_clauses ) {
			$allowed_keys = array_merge( $allowed_keys, array_keys( $meta_query_clauses ) );
		}

		$parsed = false;
		if ( $orderby == $this->query_vars['meta_key'] || $orderby == 'meta_value' ) {
			$parsed = "$wpdb->commentmeta.meta_value";
		} else if ( $orderby == 'meta_value_num' ) {
			$parsed = "$wpdb->commentmeta.meta_value+0";
		} else if ( in_array( $orderby, $allowed_keys ) ) {

			if ( isset( $meta_query_clauses[ $orderby ] ) ) {
				$meta_clause = $meta_query_clauses[ $orderby ];
				$parsed = sprintf( "CAST(%s.meta_value AS %s)", esc_sql( $meta_clause['alias'] ), esc_sql( $meta_clause['cast'] ) );
			} else {
				$parsed = "$wpdb->comments.$orderby";
			}
		}

		return $parsed;
	}

	/**
	 * Parse an 'order' query variable and cast it to ASC or DESC as necessary.
	 *
	 * @since 4.2.0
	 * @access protected
	 *
	 * @param string $order The 'order' query variable.
	 * @return string The sanitized 'order' query variable.
	 */
	protected function parse_order( $order ) {
		if ( ! is_string( $order ) || empty( $order ) ) {
			return 'DESC';
		}

		if ( 'ASC' === strtoupper( $order ) ) {
			return 'ASC';
		} else {
			return 'DESC';
		}
	}
}

/**
 * Retrieve 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 array List of comment statuses.
 */
function get_comment_statuses() {
	$status = array(
		'hold'		=> __('Unapproved'),
		/* translators: comment status  */
		'approve'	=> _x('Approved', 'adjective'),
		/* translators: comment status */
		'spam'		=> _x('Spam', 'adjective'),
	);

	return $status;
}

/**
 * The date the last comment was modified.
 *
 * @since 1.5.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param string $timezone Which timezone to use in reference to 'gmt', 'blog',
 *		or 'server' locations.
 * @return string Last comment modified date.
 */
function get_lastcommentmodified($timezone = 'server') {
	global $wpdb;
	static $cache_lastcommentmodified = array();

	if ( isset($cache_lastcommentmodified[$timezone]) )
		return $cache_lastcommentmodified[$timezone];

	$add_seconds_server = date('Z');

	switch ( strtolower($timezone)) {
		case 'gmt':
			$lastcommentmodified = $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':
			$lastcommentmodified = $wpdb->get_var("SELECT comment_date FROM $wpdb->comments WHERE comment_approved = '1' ORDER BY comment_date_gmt DESC LIMIT 1");
			break;
		case 'server':
			$lastcommentmodified = $wpdb->get_var($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;
	}

	$cache_lastcommentmodified[$timezone] = $lastcommentmodified;

	return $lastcommentmodified;
}

/**
 * The amount of comments in a post or total comments.
 *
 * A lot like {@link wp_count_comments()}, in that they both return comment
 * stats (albeit with different types). The {@link wp_count_comments()} actual
 * caches, but this function does not.
 *
 * @since 2.0.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param int $post_id Optional. Comment amount in post if > 0, else total comments blog wide.
 * @return array The amount of spam, approved, awaiting moderation, and total comments.
 */
function get_comment_count( $post_id = 0 ) {
	global $wpdb;

	$post_id = (int) $post_id;

	$where = '';
	if ( $post_id > 0 ) {
		$where = $wpdb->prepare("WHERE comment_post_ID = %d", $post_id);
	}

	$totals = (array) $wpdb->get_results("
		SELECT comment_approved, COUNT( * ) AS total
		FROM {$wpdb->comments}
		{$where}
		GROUP BY comment_approved
	", ARRAY_A);

	$comment_count = array(
		"approved"              => 0,
		"awaiting_moderation"   => 0,
		"spam"                  => 0,
		"total_comments"        => 0
	);

	foreach ( $totals as $row ) {
		switch ( $row['comment_approved'] ) {
			case 'spam':
				$comment_count['spam'] = $row['total'];
				$comment_count["total_comments"] += $row['total'];
				break;
			case 1:
				$comment_count['approved'] = $row['total'];
				$comment_count['total_comments'] += $row['total'];
				break;
			case 0:
				$comment_count['awaiting_moderation'] = $row['total'];
				$comment_count['total_comments'] += $row['total'];
				break;
			default:
				break;
		}
	}

	return $comment_count;
}

//
// Comment meta functions
//

/**
 * Add meta data field to a comment.
 *
 * @since 2.9.0
 * @link https://codex.wordpress.org/Function_Reference/add_comment_meta
 *
 * @param int $comment_id Comment ID.
 * @param string $meta_key Metadata name.
 * @param mixed $meta_value Metadata value.
 * @param bool $unique Optional, default is false. Whether the same key should not be added.
 * @return int|bool Meta ID on success, false on failure.
 */
function add_comment_meta($comment_id, $meta_key, $meta_value, $unique = false) {
	return add_metadata('comment', $comment_id, $meta_key, $meta_value, $unique);
}

/**
 * Remove 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://codex.wordpress.org/Function_Reference/delete_comment_meta
 *
 * @param int $comment_id comment ID
 * @param string $meta_key Metadata name.
 * @param mixed $meta_value Optional. Metadata value.
 * @return bool True on success, false on failure.
 */
function delete_comment_meta($comment_id, $meta_key, $meta_value = '') {
	return delete_metadata('comment', $comment_id, $meta_key, $meta_value);
}

/**
 * Retrieve comment meta field for a comment.
 *
 * @since 2.9.0
 * @link https://codex.wordpress.org/Function_Reference/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.
 * @param bool $single Whether to return a single value.
 * @return mixed Will be an array if $single is false. Will be value of meta data field if $single
 *  is true.
 */
function get_comment_meta($comment_id, $key = '', $single = false) {
	return get_metadata('comment', $comment_id, $key, $single);
}

/**
 * Update 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://codex.wordpress.org/Function_Reference/update_comment_meta
 *
 * @param int $comment_id Comment ID.
 * @param string $meta_key Metadata key.
 * @param mixed $meta_value Metadata value.
 * @param mixed $prev_value Optional. Previous value to check before removing.
 * @return int|bool Meta ID if the key didn't exist, true on successful update, false on failure.
 */
function update_comment_meta($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.
 *
 * @param object $comment Comment object.
 * @param object $user Comment author's object.
 *
 * @since 3.4.0
 */
function wp_set_comment_cookies($comment, $user) {
	if ( $user->exists() )
		return;

	/**
	 * Filter the lifetime of the comment cookie in seconds.
	 *
	 * @since 2.8.0
	 *
	 * @param int $seconds Comment cookie lifetime. Default 30000000.
	 */
	$comment_cookie_lifetime = apply_filters( 'comment_cookie_lifetime', 30000000 );
	$secure = ( 'https' === parse_url( home_url(), PHP_URL_SCHEME ) );
	setcookie( 'comment_author_' . COOKIEHASH, $comment->comment_author, time() + $comment_cookie_lifetime, COOKIEPATH, COOKIE_DOMAIN, $secure );
	setcookie( 'comment_author_email_' . COOKIEHASH, $comment->comment_author_email, time() + $comment_cookie_lifetime, COOKIEPATH, COOKIE_DOMAIN, $secure );
	setcookie( 'comment_author_url_' . COOKIEHASH, esc_url($comment->comment_author_url), time() + $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] ) ) {
		/**
		 * Filter 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] ) ) {
		/**
		 * Filter 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] ) ) {
		/**
		 * Filter 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
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param array $commentdata Contains information on the comment
 * @return mixed Signifies the approval status (0|1|'spam')
 */
function wp_allow_comment( $commentdata ) {
	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(
			"OR comment_author_email = %s ",
			wp_unslash( $commentdata['comment_author_email'] )
		);
	}
	$dupe .= $wpdb->prepare(
		") AND comment_content = %s LIMIT 1",
		wp_unslash( $commentdata['comment_content'] )
	);
	if ( $wpdb->get_var( $dupe ) ) {
		/**
		 * Fires immediately after a duplicate comment is detected.
		 *
		 * @since 3.0.0
		 *
		 * @param array $commentdata Comment data.
		 */
		do_action( 'comment_duplicate_trigger', $commentdata );
		if ( defined( 'DOING_AJAX' ) ) {
			die( __('Duplicate comment detected; it looks as though you&#8217;ve already said that!') );
		}
		wp_die( __( 'Duplicate comment detected; it looks as though you&#8217;ve already said that!' ), 409 );
	}

	/**
	 * Fires immediately before a comment is marked approved.
	 *
	 * Allows checking for comment flooding.
	 *
	 * @since 2.3.0
	 *
	 * @param string $comment_author_IP    Comment author's IP address.
	 * @param string $comment_author_email Comment author's email.
	 * @param string $comment_date_gmt     GMT date the comment was posted.
	 */
	do_action(
		'check_comment_flood',
		$commentdata['comment_author_IP'],
		$commentdata['comment_author_email'],
		$commentdata['comment_date_gmt']
	);

	if ( ! empty( $commentdata['user_id'] ) ) {
		$user = get_userdata( $commentdata['user_id'] );
		$post_author = $wpdb->get_var( $wpdb->prepare(
			"SELECT post_author FROM $wpdb->posts WHERE ID = %d LIMIT 1",
			$commentdata['comment_post_ID']
		) );
	}

	if ( isset( $user ) && ( $commentdata['user_id'] == $post_author || $user->has_cap( 'moderate_comments' ) ) ) {
		// The author and the admins get respect.
		$approved = 1;
	} else {
		// Everyone else's comments will be checked.
		if ( check_comment(
			$commentdata['comment_author'],
			$commentdata['comment_author_email'],
			$commentdata['comment_author_url'],
			$commentdata['comment_content'],
			$commentdata['comment_author_IP'],
			$commentdata['comment_agent'],
			$commentdata['comment_type']
		) ) {
			$approved = 1;
		} else {
			$approved = 0;
		}

		if ( wp_blacklist_check(
			$commentdata['comment_author'],
			$commentdata['comment_author_email'],
			$commentdata['comment_author_url'],
			$commentdata['comment_content'],
			$commentdata['comment_author_IP'],
			$commentdata['comment_agent']
		) ) {
			$approved = 'spam';
		}
	}

	/**
	 * Filter a comment's approval status before it is set.
	 *
	 * @since 2.1.0
	 *
	 * @param bool|string $approved    The approval status. Accepts 1, 0, or 'spam'.
	 * @param array       $commentdata Comment data.
	 */
	$approved = apply_filters( 'pre_comment_approved', $approved, $commentdata );
	return $approved;
}

/**
 * Check whether comment flooding is occurring.
 *
 * Won't run, if current user can manage options, so to not block
 * administrators.
 *
 * @since 2.3.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param string $ip Comment IP.
 * @param string $email Comment author email address.
 * @param string $date MySQL time string.
 */
function check_comment_flood_db( $ip, $email, $date ) {
	global $wpdb;
	if ( current_user_can( 'manage_options' ) )
		return; // don't throttle admins
	$hour_ago = gmdate( 'Y-m-d H:i:s', time() - HOUR_IN_SECONDS );
	if ( $lasttime = $wpdb->get_var( $wpdb->prepare( "SELECT `comment_date_gmt` FROM `$wpdb->comments` WHERE `comment_date_gmt` >= %s AND ( `comment_author_IP` = %s OR `comment_author_email` = %s ) ORDER BY `comment_date_gmt` DESC LIMIT 1", $hour_ago, $ip, $email ) ) ) {
		$time_lastcomment = mysql2date('U', $lasttime, false);
		$time_newcomment  = mysql2date('U', $date, false);
		/**
		 * Filter the comment flood status.
		 *
		 * @since 2.1.0
		 *
		 * @param bool $bool             Whether a comment flood is occurring. Default false.
		 * @param int  $time_lastcomment Timestamp of when the last comment was posted.
		 * @param int  $time_newcomment  Timestamp of when the new comment was posted.
		 */
		$flood_die = apply_filters( 'comment_flood_filter', false, $time_lastcomment, $time_newcomment );
		if ( $flood_die ) {
			/**
			 * Fires before the comment flood message is triggered.
			 *
			 * @since 1.5.0
			 *
			 * @param int $time_lastcomment Timestamp of when the last comment was posted.
			 * @param int $time_newcomment  Timestamp of when the new comment was posted.
			 */
			do_action( 'comment_flood_trigger', $time_lastcomment, $time_newcomment );

			if ( defined('DOING_AJAX') )
				die( __('You are posting comments too quickly. Slow down.') );

			wp_die( __( 'You are posting comments too quickly. Slow down.' ), 429 );
		}
	}
}

/**
 * Separates an array of comments into an array keyed by comment_type.
 *
 * @since 2.7.0
 *
 * @param array $comments Array of comments
 * @return array Array of comments keyed by comment_type.
 */
function separate_comments(&$comments) {
	$comments_by_type = array('comment' => array(), 'trackback' => array(), 'pingback' => array(), 'pings' => array());
	$count = count($comments);
	for ( $i = 0; $i < $count; $i++ ) {
		$type = $comments[$i]->comment_type;
		if ( empty($type) )
			$type = 'comment';
		$comments_by_type[$type][] = &$comments[$i];
		if ( 'trackback' == $type || 'pingback' == $type )
			$comments_by_type['pings'][] = &$comments[$i];
	}

	return $comments_by_type;
}

/**
 * Calculate the total number of comment pages.
 *
 * @since 2.7.0
 *
 * @uses Walker_Comment
 *
 * @param array $comments Optional array of comment objects. Defaults to $wp_query->comments
 * @param int $per_page Optional comments per page.
 * @param boolean $threaded Optional control over flat or threaded comments.
 * @return int Number of comment pages.
 */
function get_comment_pages_count( $comments = null, $per_page = null, $threaded = null ) {
	global $wp_query;

	if ( null === $comments && null === $per_page && null === $threaded && !empty($wp_query->max_num_comment_pages) )
		return $wp_query->max_num_comment_pages;

	if ( ( ! $comm