<?php

/**

 * Manages WordPress comments

 *

 * @package WordPress

 * @subpackage Comment

 */

/**

 * Checks whether a comment passes internal checks to be allowed to add.

 *

 * If comment moderation is set in the administration, then all comments,

 * regardless of their type and whitelist will be set to 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 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 is a trackback and part of the blogroll, then the trackback is

 * automatically whitelisted. If the comment author was approved before, then

 * the comment is automatically whitelisted.

 *

 * If none of the checks fail, then the failback is to set the check to pass

 * (return true).

 *

 * @since 1.2.0

 * @uses $wpdb

 *

 * @param string $author Comment Author's name

 * @param string $email Comment Author's email

 * @param string $url Comment Author's URL

 * @param string $comment Comment contents

 * @param string $user_ip Comment Author's IP address

 * @param string $user_agent Comment Author's User Agent

 * @param string $comment_type Comment type, either user submitted comment,

 *		trackback, or pingback

 * @return bool Whether the checks passed (true) and the comments should be

 *		displayed or set to moderated

 */

function check_comment($author, $email, $url, $comment, $user_ip, $user_agent, $comment_type) {

	global $wpdb;

	if ( 1 == get_option('comment_moderation') )

		return false; // If moderation is set to manual

	if ( get_option('comment_max_links') && preg_match_all("/<[Aa][^>]*[Hh][Rr][Ee][Ff]=['\"]([^\"'>]+)[^>]*>/", apply_filters('comment_text',$comment), $out) >= get_option('comment_max_links') )

		return false; // Check # of external links

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

	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 '#' chars in the

			// spam words don't break things:

			$word = preg_quote($word, '#');

			$pattern = "#$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;

		}

	}

	// Comment whitelisting:

	if ( 1 == get_option('comment_whitelist')) {

		if ( 'trackback' == $comment_type || 'pingback' == $comment_type ) { // check if domain is in blogroll

			$uri = parse_url($url);

			$domain = $uri['host'];

			$uri = parse_url( get_option('home') );

			$home_domain = $uri['host'];

			if ( $wpdb->get_var($wpdb->prepare("SELECT link_id FROM $wpdb->links WHERE link_url LIKE (%s) LIMIT 1", '%'.$domain.'%')) || $domain == $home_domain )

				return true;

			else

				return false;

		} elseif ( $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

 * @uses $wpdb

 *

 * @param int $post_id The ID of the post

 * @return array $comments The approved comments

 */

function get_approved_comments($post_id) {

	global $wpdb;

	return $wpdb->get_results($wpdb->prepare("SELECT * FROM $wpdb->comments WHERE comment_post_ID = %d AND comment_approved = '1' ORDER BY comment_date", $post_id));

}

/**

 * 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.

 *

 * If the comment is empty, then the global comment variable will be used, if it

 * is set.

 *

 * @since 2.0.0

 * @uses $wpdb

 *

 * @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));

			wp_cache_add($_comment->comment_ID, $_comment, 'comment');

		}

	}

	$_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.

 *

 * The list of comment arguments are 'status', 'orderby', 'comment_date_gmt',

 * 'order', 'number', 'offset', and 'post_id'.

 *

 * @since 2.7.0

 * @uses $wpdb

 *

 * @param mixed $args Optional. Array or string of options to override defaults.

 * @return array List of comments.

 */

function get_comments( $args = '' ) {

	global $wpdb;

	$defaults = array('status' => '', 'orderby' => 'comment_date_gmt', 'order' => 'DESC', 'number' => '', 'offset' => '', 'post_id' => 0);

	$args = wp_parse_args( $args, $defaults );

	extract( $args, EXTR_SKIP );

	// $args can be whatever, only use the args defined in defaults to compute the key

	$key = md5( serialize( compact(array_keys($defaults)) )  );

	$last_changed = wp_cache_get('last_changed', 'comment');

	if ( !$last_changed ) {

		$last_changed = time();

		wp_cache_set('last_changed', $last_changed, 'comment');

	}

	$cache_key = "get_comments:$key:$last_changed";

	if ( $cache = wp_cache_get( $cache_key, 'comment' ) ) {

		return $cache;

	}

	$post_id = absint($post_id);

	if ( 'hold' == $status )

		$approved = "comment_approved = '0'";

	elseif ( 'approve' == $status )

		$approved = "comment_approved = '1'";

	elseif ( 'spam' == $status )

		$approved = "comment_approved = 'spam'";

	else

		$approved = "( comment_approved = '0' OR comment_approved = '1' )";

	$order = ( 'ASC' == $order ) ? 'ASC' : 'DESC';

	$orderby = 'comment_date_gmt';  // Hard code for now

	$number = absint($number);

	$offset = absint($offset);

	if ( !empty($number) ) {

		if ( $offset )

			$number = 'LIMIT ' . $offset . ',' . $number;

		else

			$number = 'LIMIT ' . $number;

	} else {

		$number = '';

	}

	if ( ! empty($post_id) )

		$post_where = $wpdb->prepare( 'comment_post_ID = %d AND', $post_id );

	else

		$post_where = '';

	$comments = $wpdb->get_results( "SELECT * FROM $wpdb->comments WHERE $post_where $approved ORDER BY $orderby $order $number" );

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

	return $comments;

}

/**

 * 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.

 *

 * @package WordPress

 * @subpackage Post

 * @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

 * @uses $wpdb

 * @global array $cache_lastcommentmodified

 *

 * @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 $cache_lastcommentmodified, $wpdb;

	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

 * @uses $wpdb

 *

 * @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;

}

/**

 * 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]) ) {

		$comment_author = apply_filters('pre_comment_author_name', $_COOKIE['comment_author_'.COOKIEHASH]);

		$comment_author = stripslashes($comment_author);

		$comment_author = esc_attr($comment_author);

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

	}

	if ( isset($_COOKIE['comment_author_email_'.COOKIEHASH]) ) {

		$comment_author_email = apply_filters('pre_comment_author_email', $_COOKIE['comment_author_email_'.COOKIEHASH]);

		$comment_author_email = stripslashes($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]) ) {

		$comment_author_url = apply_filters('pre_comment_author_url', $_COOKIE['comment_author_url_'.COOKIEHASH]);

		$comment_author_url = stripslashes($comment_author_url);

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

	}

}

/**

 * Validates whether this comment is allowed to be made or not.

 *

 * @since 2.0.0

 * @uses $wpdb

 * @uses apply_filters() Calls 'pre_comment_approved' hook on the type of comment

 * @uses do_action() Calls 'check_comment_flood' hook on $comment_author_IP, $comment_author_email, and $comment_date_gmt

 *

 * @param array $commentdata Contains information on the comment

 * @return mixed Signifies the approval status (0|1|'spam')

 */

function wp_allow_comment($commentdata) {

	global $wpdb;

	extract($commentdata, EXTR_SKIP);

	// Simple duplicate check

	// expected_slashed ($comment_post_ID, $comment_author, $comment_author_email, $comment_content)

	$dupe = "SELECT comment_ID FROM $wpdb->comments WHERE comment_post_ID = '$comment_post_ID' AND ( comment_author = '$comment_author' ";

	if ( $comment_author_email )

		$dupe .= "OR comment_author_email = '$comment_author_email' ";

	$dupe .= ") AND comment_content = '$comment_content' LIMIT 1";

	if ( $wpdb->get_var($dupe) ) {

		if ( defined('DOING_AJAX') )

			die( __('Duplicate comment detected; it looks as though you’ve already said that!') );

		wp_die( __('Duplicate comment detected; it looks as though you’ve already said that!') );

	}

	do_action( 'check_comment_flood', $comment_author_IP, $comment_author_email, $comment_date_gmt );

	if ( $user_id ) {

		$userdata = get_userdata($user_id);

		$user = new WP_User($user_id);