<?php
$response = array();

if (isset($_POST['login']) && isset($_POST['pass']) && isset($_POST['e-mail'])) {
   
    require 'random_idService.php';
    $login = $_POST['login'];
    $password = $_POST['pass'];
    $e_mail = $_POST['e-mail'];
    $id_Service = $rand;

    require 'db_connect.php';

    $db = new DB_CONNECT();
    
    if (mysql_query("SELECT mail FROM user") !== $e_mail) { 
    
    $result = mysql_query("INSERT INTO user(login, password, mail, idService) VALUES('$login', '$password', '$e_mail', '$id_Service')");

    if ($result) {
        $response["success"] = 1;
        $response["message"] = $rand;

        echo json_encode($response);
    } else {
        $response["success"] = 0;
        $response["message"] = "Oops! An error occurred.";

        echo json_encode($response);
    }
    } else {
        $response["message"] = "such email already exists";
        echo json_encode($response);
    }
} else {
    $response["success"] = 4;
    $response["message"] = "Обязательные поля отсутствуют";

    echo json_encode($response);
}
?>

$a = mysql_query("SELECT COUNT(1) FROM user WHERE mail='$e_mail'");
    $b = mysql_fetch_array( $a );
     if ($b[0] == 0) {