bottega/simple-membership/classes/class.swpm-ajax.php

<?php
/**
 * Handles various AJAX calls
 */

class SwpmAjax {

    public static function validate_email_ajax() {
        global $wpdb;
        $field_value = filter_input(INPUT_GET, 'fieldValue');
        $field_id = filter_input(INPUT_GET, 'fieldId');
        $member_id = filter_input(INPUT_GET, 'member_id');
        if (!check_ajax_referer( 'swpm-rego-form-ajax-nonce', 'nonce', false )) {
            echo '[ "' . $field_id .  '",false, "'.SwpmUtils::_('Nonce check failed. Please reload page.').'" ]' ;
            exit;
        }
        if (!is_email($field_value)){
            echo '[ "' . $field_id .  '",false, "'.SwpmUtils::_('Invalid Email Address').'" ]' ;
            exit;
        }
        $table = $wpdb->prefix . "swpm_members_tbl";
        $query = $wpdb->prepare("SELECT member_id FROM $table WHERE email = %s AND user_name != ''", $field_value);
        $db_id = $wpdb->get_var($query) ;
        $exists = ($db_id > 0) && $db_id != $member_id;
        echo '[ "' . $field_id . (($exists) ? '",false, "&chi;&nbsp;'.SwpmUtils::_('Already taken').'"]' : '",true, "&radic;&nbsp;'.SwpmUtils::_('Available'). '"]');
        exit;
    }

    public static function validate_user_name_ajax() {
        global $wpdb;
        $field_value = filter_input(INPUT_GET, 'fieldValue');
        $field_id = filter_input(INPUT_GET, 'fieldId');
        if (!check_ajax_referer( 'swpm-rego-form-ajax-nonce', 'nonce', false )) {
            echo '[ "' . $field_id .  '",false, "'.SwpmUtils::_('Nonce check failed. Please reload page.').'" ]' ;
            exit;
        }
        if (!SwpmMemberUtils::is_valid_user_name($field_value)){
            echo '[ "' . $field_id . '",false,"&chi;&nbsp;'. SwpmUtils::_('Name contains invalid character'). '"]';
            exit;
        }
        $table = $wpdb->prefix . "swpm_members_tbl";
        $query = $wpdb->prepare("SELECT COUNT(*) FROM $table WHERE user_name = %s", $field_value);
        $exists = $wpdb->get_var($query) > 0;
        echo '[ "' . $field_id . (($exists) ? '",false,"&chi;&nbsp;'. SwpmUtils::_('Already taken'). '"]' :
            '",true,"&radic;&nbsp;'.SwpmUtils::_('Available'). '"]');
        exit;
    }

}