CaffGeek/MBACNationals

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Web.Admin/2014/wordpress/wp-content/plugins/akismet/class.akismet.php

Summary

Maintainability
F
5 days
Test Coverage
<?php

class Akismet {
    const API_HOST = 'rest.akismet.com';
    const API_PORT = 80;
    const MAX_DELAY_BEFORE_MODERATION_EMAIL = 86400; // One day in seconds

    private static $last_comment = '';
    private static $initiated = false;
    private static $prevent_moderation_email_for_these_comments = array();
    private static $last_comment_result = null;
    
    public static function init() {
        if ( ! self::$initiated ) {
            self::init_hooks();
        }
    }

    /**
     * Initializes WordPress hooks
     */
    private static function init_hooks() {
        self::$initiated = true;

        add_action( 'wp_insert_comment', array( 'Akismet', 'auto_check_update_meta' ), 10, 2 );
        add_action( 'preprocess_comment', array( 'Akismet', 'auto_check_comment' ), 1 );
        add_action( 'akismet_scheduled_delete', array( 'Akismet', 'delete_old_comments' ) );
        add_action( 'akismet_scheduled_delete', array( 'Akismet', 'delete_old_comments_meta' ) );
        add_action( 'akismet_schedule_cron_recheck', array( 'Akismet', 'cron_recheck' ) );

        $akismet_comment_nonce_option = apply_filters( 'akismet_comment_nonce', get_option( 'akismet_comment_nonce' ) );

        if ( $akismet_comment_nonce_option == 'true' || $akismet_comment_nonce_option == '' )
            add_action( 'comment_form',  array( 'Akismet',  'add_comment_nonce' ), 1 );

        add_action( 'admin_footer-edit-comments.php', array( 'Akismet', 'load_form_js' ) );
        add_action( 'comment_form', array( 'Akismet', 'load_form_js' ) );
        add_action( 'comment_form', array( 'Akismet', 'inject_ak_js' ) );

        add_filter( 'comment_moderation_recipients', array( 'Akismet', 'disable_moderation_emails_if_unreachable' ), 1000, 2 );
        add_filter( 'pre_comment_approved', array( 'Akismet', 'last_comment_status' ), 10, 2 );

        if ( '3.0.5' == $GLOBALS['wp_version'] ) {
            remove_filter( 'comment_text', 'wp_kses_data' );
            if ( is_admin() )
                add_filter( 'comment_text', 'wp_kses_post' );
        }
    }

    public static function get_api_key() {
        return defined('WPCOM_API_KEY') ? constant('WPCOM_API_KEY') : get_option('wordpress_api_key');
    }

    public static function check_key_status( $key, $ip = null ) {
        return self::http_post( http_build_query( array( 'key' => $key, 'blog' => get_option('home') ) ), 'verify-key', $ip );
    }

    public static function verify_key( $key, $ip = null ) {
        $response = self::check_key_status( $key, $ip );

        if ( $response[1] != 'valid' && $response[1] != 'invalid' )
            return 'failed';

        self::update_alert( $response );

        return $response[1];
    }

    public static function auto_check_comment( $commentdata ) {
        self::$last_comment_result = null;

        $comment = $commentdata;

        $comment['user_ip']      = self::get_ip_address();
        $comment['user_agent']   = self::get_user_agent();
        $comment['referrer']     = self::get_referer();
        $comment['blog']         = get_option('home');
        $comment['blog_lang']    = get_locale();
        $comment['blog_charset'] = get_option('blog_charset');
        $comment['permalink']    = get_permalink( $comment['comment_post_ID'] );

        if ( !empty( $comment['user_ID'] ) )
            $comment['user_role'] = Akismet::get_user_roles( $comment['user_ID'] );

        $akismet_nonce_option = apply_filters( 'akismet_comment_nonce', get_option( 'akismet_comment_nonce' ) );
        $comment['akismet_comment_nonce'] = 'inactive';
        if ( $akismet_nonce_option == 'true' || $akismet_nonce_option == '' ) {
            $comment['akismet_comment_nonce'] = 'failed';
            if ( isset( $_POST['akismet_comment_nonce'] ) && wp_verify_nonce( $_POST['akismet_comment_nonce'], 'akismet_comment_nonce_' . $comment['comment_post_ID'] ) )
                $comment['akismet_comment_nonce'] = 'passed';

            // comment reply in wp-admin
            if ( isset( $_POST['_ajax_nonce-replyto-comment'] ) && check_ajax_referer( 'replyto-comment', '_ajax_nonce-replyto-comment' ) )
                $comment['akismet_comment_nonce'] = 'passed';

        }

        if ( self::is_test_mode() )
            $comment['is_test'] = 'true';

        foreach( $_POST as $key => $value ) {
            if ( is_string( $value ) )
                $comment["POST_{$key}"] = $value;
        }

        $ignore = array( 'HTTP_COOKIE', 'HTTP_COOKIE2', 'PHP_AUTH_PW' );

        foreach ( $_SERVER as $key => $value ) {
            if ( !in_array( $key, $ignore ) && is_string($value) )
                $comment["$key"] = $value;
            else
                $comment["$key"] = '';
        }

        $post = get_post( $comment['comment_post_ID'] );
        $comment[ 'comment_post_modified_gmt' ] = $post->post_modified_gmt;

        $response = self::http_post( http_build_query( $comment ), 'comment-check' );

        do_action( 'akismet_comment_check_response', $response );

        self::update_alert( $response );

        $commentdata['comment_as_submitted'] = $comment;
        $commentdata['akismet_result']       = $response[1];

        if ( isset( $response[0]['x-akismet-pro-tip'] ) )
            $commentdata['akismet_pro_tip'] = $response[0]['x-akismet-pro-tip'];

        if ( 'true' == $response[1] ) {
            // akismet_spam_count will be incremented later by comment_is_spam()
            self::$last_comment_result = 'spam';

            $discard = ( isset( $commentdata['akismet_pro_tip'] ) && $commentdata['akismet_pro_tip'] === 'discard' && self::allow_discard() );

            do_action( 'akismet_spam_caught', $discard );

            if ( $discard ) {
                // akismet_result_spam() won't be called so bump the counter here
                if ( $incr = apply_filters('akismet_spam_count_incr', 1) )
                    update_option( 'akismet_spam_count', get_option('akismet_spam_count') + $incr );
                $redirect_to = isset( $_SERVER['HTTP_REFERER'] ) ? $_SERVER['HTTP_REFERER'] : get_permalink( $post );
                wp_safe_redirect( esc_url_raw( $redirect_to ) );
                die();
            }
        }
        
        // if the response is neither true nor false, hold the comment for moderation and schedule a recheck
        if ( 'true' != $response[1] && 'false' != $response[1] ) {
            if ( !current_user_can('moderate_comments') ) {
                // Comment status should be moderated
                self::$last_comment_result = '0';
            }
            if ( function_exists('wp_next_scheduled') && function_exists('wp_schedule_single_event') ) {
                if ( !wp_next_scheduled( 'akismet_schedule_cron_recheck' ) ) {
                    wp_schedule_single_event( time() + 1200, 'akismet_schedule_cron_recheck' );
                }
            }

            self::$prevent_moderation_email_for_these_comments[] = $commentdata;
        }

        if ( function_exists('wp_next_scheduled') && function_exists('wp_schedule_event') ) {
            // WP 2.1+: delete old comments daily
            if ( !wp_next_scheduled( 'akismet_scheduled_delete' ) )
                wp_schedule_event( time(), 'daily', 'akismet_scheduled_delete' );
        }
        elseif ( (mt_rand(1, 10) == 3) ) {
            // WP 2.0: run this one time in ten
            self::delete_old_comments();
        }
        
        self::set_last_comment( $commentdata );
        self::fix_scheduled_recheck();

        return self::$last_comment;
    }
    
    public static function get_last_comment() {
        return self::$last_comment;
    }
    
    public static function set_last_comment( $comment ) {
        if ( is_null( $comment ) ) {
            self::$last_comment = null;
        }
        else {
            // We filter it here so that it matches the filtered comment data that we'll have to compare against later.
            // wp_filter_comment expects comment_author_IP
            self::$last_comment = wp_filter_comment(
                array_merge(
                    array( 'comment_author_IP' => self::get_ip_address() ),
                    $comment
                )
            );
        }
    }

    // this fires on wp_insert_comment.  we can't update comment_meta when auto_check_comment() runs
    // because we don't know the comment ID at that point.
    public static function auto_check_update_meta( $id, $comment ) {

        // failsafe for old WP versions
        if ( !function_exists('add_comment_meta') )
            return false;

        if ( !isset( self::$last_comment['comment_author_email'] ) )
            self::$last_comment['comment_author_email'] = '';

        // wp_insert_comment() might be called in other contexts, so make sure this is the same comment
        // as was checked by auto_check_comment
        if ( is_object( $comment ) && !empty( self::$last_comment ) && is_array( self::$last_comment ) ) {
            if ( self::matches_last_comment( $comment ) ) {
                    
                    load_plugin_textdomain( 'akismet' );
                    
                    // normal result: true or false
                    if ( self::$last_comment['akismet_result'] == 'true' ) {
                        update_comment_meta( $comment->comment_ID, 'akismet_result', 'true' );
                        self::update_comment_history( $comment->comment_ID, __('Akismet caught this comment as spam', 'akismet'), 'check-spam' );
                        if ( $comment->comment_approved != 'spam' )
                            self::update_comment_history( $comment->comment_ID, sprintf( __('Comment status was changed to %s', 'akismet'), $comment->comment_approved), 'status-changed'.$comment->comment_approved );
                    }
                    elseif ( self::$last_comment['akismet_result'] == 'false' ) {
                        update_comment_meta( $comment->comment_ID, 'akismet_result', 'false' );
                        self::update_comment_history( $comment->comment_ID, __('Akismet cleared this comment', 'akismet'), 'check-ham' );
                        if ( $comment->comment_approved == 'spam' ) {
                            if ( wp_blacklist_check($comment->comment_author, $comment->comment_author_email, $comment->comment_author_url, $comment->comment_content, $comment->comment_author_IP, $comment->comment_agent) )
                                self::update_comment_history( $comment->comment_ID, __('Comment was caught by wp_blacklist_check', 'akismet'), 'wp-blacklisted' );
                            else
                                self::update_comment_history( $comment->comment_ID, sprintf( __('Comment status was changed to %s', 'akismet'), $comment->comment_approved), 'status-changed-'.$comment->comment_approved );
                        }
                    } // abnormal result: error
                    else {
                        update_comment_meta( $comment->comment_ID, 'akismet_error', time() );
                        self::update_comment_history( $comment->comment_ID, sprintf( __('Akismet was unable to check this comment (response: %s), will automatically retry again later.', 'akismet'), substr(self::$last_comment['akismet_result'], 0, 50)), 'check-error' );
                    }

                    // record the complete original data as submitted for checking
                    if ( isset( self::$last_comment['comment_as_submitted'] ) )
                        update_comment_meta( $comment->comment_ID, 'akismet_as_submitted', self::$last_comment['comment_as_submitted'] );

                    if ( isset( self::$last_comment['akismet_pro_tip'] ) )
                        update_comment_meta( $comment->comment_ID, 'akismet_pro_tip', self::$last_comment['akismet_pro_tip'] );
            }
        }
    }

    public static function delete_old_comments() {
        global $wpdb;

        while( $comment_ids = $wpdb->get_col( $wpdb->prepare( "SELECT comment_id FROM {$wpdb->comments} WHERE DATE_SUB(NOW(), INTERVAL 15 DAY) > comment_date_gmt AND comment_approved = 'spam' LIMIT %d", defined( 'AKISMET_DELETE_LIMIT' ) ? AKISMET_DELETE_LIMIT : 10000 ) ) ) {
            if ( empty( $comment_ids ) )
                return;

            $wpdb->queries = array();

            do_action( 'delete_comment', $comment_ids );

            $comma_comment_ids = implode( ', ', array_map('intval', $comment_ids) );

            $wpdb->query("DELETE FROM {$wpdb->comments} WHERE comment_id IN ( $comma_comment_ids )");
            $wpdb->query("DELETE FROM {$wpdb->commentmeta} WHERE comment_id IN ( $comma_comment_ids )");

            clean_comment_cache( $comment_ids );
        }

        if ( apply_filters( 'akismet_optimize_table', ( mt_rand(1, 5000) == 11), $wpdb->comments ) ) // lucky number
            $wpdb->query("OPTIMIZE TABLE {$wpdb->comments}");
    }

    public static function delete_old_comments_meta() {
        global $wpdb;

        $interval = apply_filters( 'akismet_delete_commentmeta_interval', 15 );

        # enfore a minimum of 1 day
        $interval = absint( $interval );
        if ( $interval < 1 )
            $interval = 1;

        // akismet_as_submitted meta values are large, so expire them
        // after $interval days regardless of the comment status
        while ( $comment_ids = $wpdb->get_col( $wpdb->prepare( "SELECT m.comment_id FROM {$wpdb->commentmeta} as m INNER JOIN {$wpdb->comments} as c USING(comment_id) WHERE m.meta_key = 'akismet_as_submitted' AND DATE_SUB(NOW(), INTERVAL %d DAY) > c.comment_date_gmt LIMIT 10000", $interval ) ) ) {
            if ( empty( $comment_ids ) )
                return;

            $wpdb->queries = array();

            foreach ( $comment_ids as $comment_id ) {
                delete_comment_meta( $comment_id, 'akismet_as_submitted' );
            }
        }

        if ( apply_filters( 'akismet_optimize_table', ( mt_rand(1, 5000) == 11), $wpdb->commentmeta ) ) // lucky number
            $wpdb->query("OPTIMIZE TABLE {$wpdb->commentmeta}");
    }

    // how many approved comments does this author have?
    public static function get_user_comments_approved( $user_id, $comment_author_email, $comment_author, $comment_author_url ) {
        global $wpdb;

        if ( !empty( $user_id ) )
            return (int) $wpdb->get_var( $wpdb->prepare( "SELECT COUNT(*) FROM {$wpdb->comments} WHERE user_id = %d AND comment_approved = 1", $user_id ) );

        if ( !empty( $comment_author_email ) )
            return (int) $wpdb->get_var( $wpdb->prepare( "SELECT COUNT(*) FROM {$wpdb->comments} WHERE comment_author_email = %s AND comment_author = %s AND comment_author_url = %s AND comment_approved = 1", $comment_author_email, $comment_author, $comment_author_url ) );

        return 0;
    }

    // get the full comment history for a given comment, as an array in reverse chronological order
    public static function get_comment_history( $comment_id ) {

        // failsafe for old WP versions
        if ( !function_exists('add_comment_meta') )
            return false;

        $history = get_comment_meta( $comment_id, 'akismet_history', false );
        usort( $history, array( 'Akismet', '_cmp_time' ) );
        return $history;
    }

    // log an event for a given comment, storing it in comment_meta
    public static function update_comment_history( $comment_id, $message, $event=null ) {
        global $current_user;

        // failsafe for old WP versions
        if ( !function_exists('add_comment_meta') )
            return false;

        $user = '';
        if ( is_object( $current_user ) && isset( $current_user->user_login ) )
            $user = $current_user->user_login;

        $event = array(
            'time'    => self::_get_microtime(),
            'message' => $message,
            'event'   => $event,
            'user'    => $user,
        );

        // $unique = false so as to allow multiple values per comment
        $r = add_comment_meta( $comment_id, 'akismet_history', $event, false );
    }

    public static function check_db_comment( $id, $recheck_reason = 'recheck_queue' ) {
        global $wpdb;

        $c = $wpdb->get_row( $wpdb->prepare( "SELECT * FROM {$wpdb->comments} WHERE comment_ID = %d", $id ), ARRAY_A );
        if ( !$c )
            return;

        $c['user_ip']        = $c['comment_author_IP'];
        $c['user_agent']     = $c['comment_agent'];
        $c['referrer']       = '';
        $c['blog']           = get_option('home');
        $c['blog_lang']      = get_locale();
        $c['blog_charset']   = get_option('blog_charset');
        $c['permalink']      = get_permalink($c['comment_post_ID']);
        $c['recheck_reason'] = $recheck_reason;

        if ( self::is_test_mode() )
            $c['is_test'] = 'true';

        $response = self::http_post( http_build_query( $c ), 'comment-check' );

        return ( is_array( $response ) && ! empty( $response[1] ) ) ? $response[1] : false;
    }

    public static function cron_recheck() {
        global $wpdb;

        $api_key = self::get_api_key();

        $status = self::verify_key( $api_key );
        if ( get_option( 'akismet_alert_code' ) || $status == 'invalid' ) {
            // since there is currently a problem with the key, reschedule a check for 6 hours hence
            wp_schedule_single_event( time() + 21600, 'akismet_schedule_cron_recheck' );
            return false;
        }

        delete_option('akismet_available_servers');

        $comment_errors = $wpdb->get_col( "SELECT comment_id FROM {$wpdb->commentmeta} WHERE meta_key = 'akismet_error'    LIMIT 100" );
        
        load_plugin_textdomain( 'akismet' );

        foreach ( (array) $comment_errors as $comment_id ) {
            // if the comment no longer exists, or is too old, remove the meta entry from the queue to avoid getting stuck
            $comment = get_comment( $comment_id );
            if ( !$comment || strtotime( $comment->comment_date_gmt ) < strtotime( "-15 days" ) ) {
                delete_comment_meta( $comment_id, 'akismet_error' );
                delete_comment_meta( $comment_id, 'akismet_delayed_moderation_email' );
                continue;
            }

            add_comment_meta( $comment_id, 'akismet_rechecking', true );
            $status = self::check_db_comment( $comment_id, 'retry' );

            $msg = '';
            if ( $status == 'true' ) {
                $msg = __( 'Akismet caught this comment as spam during an automatic retry.' , 'akismet');
            } elseif ( $status == 'false' ) {
                $msg = __( 'Akismet cleared this comment during an automatic retry.' , 'akismet');
            }

            // If we got back a legit response then update the comment history
            // other wise just bail now and try again later.  No point in
            // re-trying all the comments once we hit one failure.
            if ( !empty( $msg ) ) {
                delete_comment_meta( $comment_id, 'akismet_error' );
                self::update_comment_history( $comment_id, $msg, 'cron-retry' );
                update_comment_meta( $comment_id, 'akismet_result', $status );
                // make sure the comment status is still pending.  if it isn't, that means the user has already moved it elsewhere.
                $comment = get_comment( $comment_id );
                if ( $comment && 'unapproved' == wp_get_comment_status( $comment_id ) ) {
                    if ( $status == 'true' ) {
                        wp_spam_comment( $comment_id );
                    } elseif ( $status == 'false' ) {
                        // comment is good, but it's still in the pending queue.  depending on the moderation settings
                        // we may need to change it to approved.
                        if ( check_comment($comment->comment_author, $comment->comment_author_email, $comment->comment_author_url, $comment->comment_content, $comment->comment_author_IP, $comment->comment_agent, $comment->comment_type) )
                            wp_set_comment_status( $comment_id, 1 );
                        else if ( get_comment_meta( $comment_id, 'akismet_delayed_moderation_email', true ) )
                            wp_notify_moderator( $comment_id );
                    }
                }
                
                delete_comment_meta( $comment_id, 'akismet_delayed_moderation_email' );
            } else {
                // If this comment has been pending moderation for longer than MAX_DELAY_BEFORE_MODERATION_EMAIL,
                // send a moderation email now.
                if ( ( intval( gmdate( 'U' ) ) - strtotime( $comment->comment_date_gmt ) ) < self::MAX_DELAY_BEFORE_MODERATION_EMAIL ) {
                    delete_comment_meta( $comment_id, 'akismet_delayed_moderation_email' );
                    wp_notify_moderator( $comment_id );
                }

                delete_comment_meta( $comment_id, 'akismet_rechecking' );
                wp_schedule_single_event( time() + 1200, 'akismet_schedule_cron_recheck' );
                return;
            }
            delete_comment_meta( $comment_id, 'akismet_rechecking' );
        }

        $remaining = $wpdb->get_var( "SELECT COUNT(*) FROM {$wpdb->commentmeta} WHERE meta_key = 'akismet_error'" );
        if ( $remaining && !wp_next_scheduled('akismet_schedule_cron_recheck') ) {
            wp_schedule_single_event( time() + 1200, 'akismet_schedule_cron_recheck' );
        }
    }

    public static function fix_scheduled_recheck() {
        $future_check = wp_next_scheduled( 'akismet_schedule_cron_recheck' );
        if ( !$future_check ) {
            return;
        }

        if ( get_option( 'akismet_alert_code' ) > 0 ) {
            return;
        }

        $check_range = time() + 1200;
        if ( $future_check > $check_range ) {
            wp_clear_scheduled_hook( 'akismet_schedule_cron_recheck' );
            wp_schedule_single_event( time() + 300, 'akismet_schedule_cron_recheck' );
        }
    }

    public static function add_comment_nonce( $post_id ) {
        echo '<p style="display: none;">';
        wp_nonce_field( 'akismet_comment_nonce_' . $post_id, 'akismet_comment_nonce', FALSE );
        echo '</p>';
    }

    public static function is_test_mode() {
        return defined('AKISMET_TEST_MODE') && AKISMET_TEST_MODE;
    }
    
    public static function allow_discard() {
        if ( defined( 'DOING_AJAX' ) && DOING_AJAX )
            return false;
        if ( is_user_logged_in() )
            return false;
    
        return ( get_option( 'akismet_strictness' ) === '1'  );
    }

    public static function get_ip_address() {
        return isset( $_SERVER['REMOTE_ADDR'] ) ? $_SERVER['REMOTE_ADDR'] : null;
    }
    
    /**
     * Do these two comments, without checking the comment_ID, "match"?
     *
     * @param mixed $comment1 A comment object or array.
     * @param mixed $comment2 A comment object or array.
     * @return bool Whether the two comments should be treated as the same comment.
     */
    private static function comments_match( $comment1, $comment2 ) {
        $comment1 = (array) $comment1;
        $comment2 = (array) $comment2;
        
        return (
               isset( $comment1['comment_post_ID'], $comment2['comment_post_ID'] )
            && intval( $comment1['comment_post_ID'] ) == intval( $comment2['comment_post_ID'] )
            && $comment1['comment_author'] == $comment2['comment_author']
            && $comment1['comment_author_email'] == $comment2['comment_author_email']
        );
    }
    
    // Does the supplied comment match the details of the one most recently stored in self::$last_comment?
    public static function matches_last_comment( $comment ) {
        if ( is_object( $comment ) )
            $comment = (array) $comment;

        return self::comments_match( self::$last_comment, $comment );
    }

    private static function get_user_agent() {
        return isset( $_SERVER['HTTP_USER_AGENT'] ) ? $_SERVER['HTTP_USER_AGENT'] : null;
    }

    private static function get_referer() {
        return isset( $_SERVER['HTTP_REFERER'] ) ? $_SERVER['HTTP_REFERER'] : null;
    }

    // return a comma-separated list of role names for the given user
    public static function get_user_roles( $user_id ) {
        $roles = false;

        if ( !class_exists('WP_User') )
            return false;

        if ( $user_id > 0 ) {
            $comment_user = new WP_User( $user_id );
            if ( isset( $comment_user->roles ) )
                $roles = join( ',', $comment_user->roles );
        }

        if ( is_multisite() && is_super_admin( $user_id ) ) {
            if ( empty( $roles ) ) {
                $roles = 'super_admin';
            } else {
                $comment_user->roles[] = 'super_admin';
                $roles = join( ',', $comment_user->roles );
            }
        }

        return $roles;
    }

    // filter handler used to return a spam result to pre_comment_approved
    public static function last_comment_status( $approved, $comment ) {
        // Only do this if it's the correct comment
        if ( is_null(self::$last_comment_result) || ! self::matches_last_comment( $comment ) ) {
            self::log( "comment_is_spam mismatched comment, returning unaltered $approved" );
            return $approved;
        }

        // bump the counter here instead of when the filter is added to reduce the possibility of overcounting
        if ( $incr = apply_filters('akismet_spam_count_incr', 1) )
            update_option( 'akismet_spam_count', get_option('akismet_spam_count') + $incr );

        return self::$last_comment_result;
    }
    
    /**
     * If Akismet is temporarily unreachable, we don't want to "spam" the blogger with
     * moderation emails for comments that will be automatically cleared or spammed on
     * the next retry.
     *
     * For comments that will be rechecked later, empty the list of email addresses that
     * the moderation email would be sent to.
     *
     * @param array $emails An array of email addresses that the moderation email will be sent to.
     * @param int $comment_id The ID of the relevant comment.
     * @return array An array of email addresses that the moderation email will be sent to.
     */
    public static function disable_moderation_emails_if_unreachable( $emails, $comment_id ) {
        if ( ! empty( self::$prevent_moderation_email_for_these_comments ) && ! empty( $emails ) ) {
            $comment = get_comment( $comment_id );

            foreach ( self::$prevent_moderation_email_for_these_comments as $possible_match ) {
                if ( self::comments_match( $possible_match, $comment ) ) {
                    update_comment_meta( $comment_id, 'akismet_delayed_moderation_email', true );
                    return array();
                }
            }
        }

        return $emails;
    }

    public static function _cmp_time( $a, $b ) {
        return $a['time'] > $b['time'] ? -1 : 1;
    }

    public static function _get_microtime() {
        $mtime = explode( ' ', microtime() );
        return $mtime[1] + $mtime[0];
    }

    /**
     * Make a POST request to the Akismet API.
     *
     * @param string $request The body of the request.
     * @param string $path The path for the request.
     * @param string $ip The specific IP address to hit.
     * @return array A two-member array consisting of the headers and the response body, both empty in the case of a failure.
     */
    public static function http_post( $request, $path, $ip=null ) {

        $akismet_ua = sprintf( 'WordPress/%s | Akismet/%s', $GLOBALS['wp_version'], constant( 'AKISMET_VERSION' ) );
        $akismet_ua = apply_filters( 'akismet_ua', $akismet_ua );

        $content_length = strlen( $request );

        $api_key   = self::get_api_key();
        $host      = self::API_HOST;

        if ( !empty( $api_key ) )
            $host = $api_key.'.'.$host;

        $http_host = $host;
        // use a specific IP if provided
        // needed by Akismet_Admin::check_server_connectivity()
        if ( $ip && long2ip( ip2long( $ip ) ) ) {
            $http_host = $ip;
        }

        $http_args = array(
            'body' => $request,
            'headers' => array(
                'Content-Type' => 'application/x-www-form-urlencoded; charset=' . get_option( 'blog_charset' ),
                'Host' => $host,
                'User-Agent' => $akismet_ua,
            ),
            'httpversion' => '1.0',
            'timeout' => 15
        );

        $akismet_url = "http://{$http_host}/1.1/{$path}";
        $response = wp_remote_post( $akismet_url, $http_args );
        Akismet::log( compact( 'akismet_url', 'http_args', 'response' ) );
        if ( is_wp_error( $response ) )
            return array( '', '' );

        return array( $response['headers'], $response['body'] );
    }

    // given a response from an API call like check_key_status(), update the alert code options if an alert is present.
    private static function update_alert( $response ) {
        $code = $msg = null;
        if ( isset( $response[0]['x-akismet-alert-code'] ) ) {
            $code = $response[0]['x-akismet-alert-code'];
            $msg  = $response[0]['x-akismet-alert-msg'];
        }

        // only call update_option() if the value has changed
        if ( $code != get_option( 'akismet_alert_code' ) ) {
            if ( ! $code ) {
                delete_option( 'akismet_alert_code' );
                delete_option( 'akismet_alert_msg' );
            }
            else {
                update_option( 'akismet_alert_code', $code );
                update_option( 'akismet_alert_msg', $msg );
            }
        }
    }

    public static function load_form_js() {
        wp_enqueue_script( 'akismet-form', AKISMET__PLUGIN_URL . '_inc/form.js', array( 'jquery' ), AKISMET_VERSION );
        wp_print_scripts( 'akismet-form' );
    }

    public static function inject_ak_js( $fields ) {
        echo '<p style="display: none;">';
        echo '<input type="hidden" id="ak_js" name="ak_js" value="' . mt_rand( 0, 250 ) . '"/>';
        echo '</p>';
    }

    private static function bail_on_activation( $message, $deactivate = true ) {
?>
<!doctype html>
<html>
<head>
<meta charset="<?php bloginfo( 'charset' ); ?>">
<style>
* {
    text-align: center;
    margin: 0;
    padding: 0;
    font-family: "Lucida Grande",Verdana,Arial,"Bitstream Vera Sans",sans-serif;
}
p {
    margin-top: 1em;
    font-size: 18px;
}
</style>
<body>
<p><?php echo esc_html( $message ); ?></p>
</body>
</html>
<?php
        if ( $deactivate ) {
            $plugins = get_option( 'active_plugins' );
            $akismet = plugin_basename( AKISMET__PLUGIN_DIR . 'akismet.php' );
            $update  = false;
            foreach ( $plugins as $i => $plugin ) {
                if ( $plugin === $akismet ) {
                    $plugins[$i] = false;
                    $update = true;
                }
            }

            if ( $update ) {
                update_option( 'active_plugins', array_filter( $plugins ) );
            }
        }
        exit;
    }

    public static function view( $name, array $args = array() ) {
        $args = apply_filters( 'akismet_view_arguments', $args, $name );
        
        foreach ( $args AS $key => $val ) {
            $$key = $val;
        }
        
        load_plugin_textdomain( 'akismet' );

        $file = AKISMET__PLUGIN_DIR . 'views/'. $name . '.php';

        include( $file );
    }

    /**
     * Attached to activate_{ plugin_basename( __FILES__ ) } by register_activation_hook()
     * @static
     */
    public static function plugin_activation() {
        if ( version_compare( $GLOBALS['wp_version'], AKISMET__MINIMUM_WP_VERSION, '<' ) ) {
            load_plugin_textdomain( 'akismet' );
            
            $message = '<strong>'.sprintf(esc_html__( 'Akismet %s requires WordPress %s or higher.' , 'akismet'), AKISMET_VERSION, AKISMET__MINIMUM_WP_VERSION ).'</strong> '.sprintf(__('Please <a href="%1$s">upgrade WordPress</a> to a current version, or <a href="%2$s">downgrade to version 2.4 of the Akismet plugin</a>.', 'akismet'), 'https://codex.wordpress.org/Upgrading_WordPress', 'http://wordpress.org/extend/plugins/akismet/download/');

            Akismet::bail_on_activation( $message );
        }
    }

    /**
     * Removes all connection options
     * @static
     */
    public static function plugin_deactivation( ) {
        //tidy up
    }

    public static function log( $akismet_debug ) {
        if ( defined( 'WP_DEBUG_LOG' ) && WP_DEBUG_LOG )
            error_log( print_r( compact( 'akismet_debug' ), 1 ) ); //send message to debug.log when in debug mode
    }
}