include_once("shared/Database.php");
include_once("shared/SRPConstants.php");
include_once("shared/SRP.php");

define(SRP_PRIME_SIZE, "8192");

$dbh = new Database();

$username = $_REQUEST["username"];
$password = $_REQUEST["password"];
$email = $_REQUEST["email"];

$escapedUsername = mysql_real_escape_string($username);

$result = $dbh->query('SELECT * FROM users WHERE username= ' . $escapedUsername);

if (!$result)
{
  print ("<h1>Database Error</h1><p>Could not retrieve data.</p>");
}
else
{
  $rows = mysql_num_rows($result);
  if ($rows > 0)
  {
    print ("<h1>Username in Use</h1><p>Could not create the account because the username is already in use.</p>");
  }
  else
  {
    $salt = SRP_Gen_Salt();
    $g = SRP_Get_Default_g(SRP_PRIME_SIZE);
    $N = SRP_Get_Default_N(SRP_PRIME_SIZE);
    $x = SRP_Calc_x($salt, $username, $password);
    $v = SRP_Calc_v($x, $g, $N);

    $binS = hex2bytes(gmp_strval($salt, 16));
    $binV = hex2bytes(gmp_strval($v   , 16));

    $escapedSalt     = mysql_real_escape_string($binS);
    $escapedVerifier = mysql_real_escape_string($binV);
    $escapedEmail    = mysql_real_escape_string($email);

    $dbh->query("INSERT INTO users VALUES (NULL".
                                         ",\"".$escapedUsername."\"".
                                         ",\"".$escapedSalt."\"".
                                         ",\"".$escapedVerifier."\")");
    print ("<h1>Congratulations</h1><p>Your account has been created.</p>");
  }
}