<script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js"></script>
<script type="text/javascript">
   $(document).ready(function(){
      $("#phone").submit(function()
      {
          var phone_no = $('#phone_no').val();

          if(phone_no != '')
          {

              $.post("sendcode.php", { phone_no: phone_no },
                    function(data)
                    {
                       $(".result").html(data);
                    },
                    "html"
              );

          }

          return false;
      });
   });
</script>

<div class = "result"></div>
<p>Enter your phone number below, and we will send you a verification code to that phone number.</p>
<form id = "phone" method  = "POST" action = "">
<label for = "phone">Phone number</label>
<input name = "phone" type = "text" id = "phone_no" />
<input name = "submit" type = "submit" value = "Send Verification Code" />
</form>

<p>Enter Verification Code received to the phone number specified above in the form below.</p>

<form id = "verification" method  = "POST" action = "verify.php">
<label for = "code">Verification Code</label>
<input name = "code" type = "text" id = "code" />
<input name = "submit" type = "submit" value = "Verify" />
</form>

<?php
if(isset($_POST['code']))
{
    $verifyCode = $_POST['code'];

    /*** mysql hostname ***/
    $hostname = 'localhost';
    /*** database name ***/
    $dbname = 'sms';
    /*** mysql username ***/
    $username = 'root';
    /*** mysql password ***/
    $password = 'secret';

    try {

        $dbh = new PDO("mysql:host=$hostname;dbname=$dbname", $username, $password);

        // USER_ID is the login ID of the user
        $sql = "SELECT code FROM user WHERE id = {$user_id}";
        $sth = $dbh->query($sql);

        $code = $sth->fetchColumn();

        if($code == $verifyCode)
        {
            echo "Your account has been validated.";

            // verify user in db
            $todo = "UPDATE user SET status = 1 WHERE user_id = {$user_id}";
            $dbh->execute($todo);

        }
        else
        {
            echo "Your account has not been validated.";
        }

        $dbh = null;
    }
    catch(PDOException $e)
    {
        echo $e->getMessage();
    }
}
?>

<?php
// configuration
use TwilioRestClient;

/*** mysql hostname ***/
$hostname = 'localhost';
// database name
$dbname = 'sms';
/*** mysql username ***/
$username = 'root';
/*** mysql password ***/
$password = 'secret';
// enter SID here
$twilioSid = 'ACxxx';
// enter twilio token here
$twilioToken = 'TKxxx';
if(isset($_POST['phone_no']))
{
    try
    {
        $verifyCode = rand(1000, 9999);

        $phone = $_POST['phone_no'];

        $dbh = new PDO("mysql:host=$hostname;dbname=$dbname", $username, $password);

        /*** add verification code and phone number to db **/
        $sth = "INSERT INTO user (phone, code) VALUES(:phone, :code)";
        $command = $dbh->prepare($sth);
        $command->bindParam(':phone', $phone, PDO::PARAM_STR);
        $command->bindParam(':code', $verifyCode, PDO::PARAM_INT);
        $command->execute();

        // Require the bundled autoload file - the path may need to change
        // based on where you downloaded and unzipped the SDK
        require __DIR__ . '/Twilio/autoload.php';

            // Use the REST API Client to make requests to the Twilio REST API

            $client = new Client($twilioSid, $twilioToken);

            // Use the client to do fun stuff like send text messages!
            $client->messages->create(
                // the number you'd like to send the message to
                '+16476476476',
                array(
                    // A Twilio phone number you purchased at twilio.com/console
                    'from' => '+16746746746',
                    // the body of the text message you'd like to send
                    'body' => "Welcome to Bit, your temporary PIN code is: $verifyCode"
                )
            );

        echo '<p>A verification code was sent to your phone number. Please enter it below.</p>';

        /*** close the database connection ***/
        $dbh = null;
    }
    catch(PDOException $e)
    {
        echo $e->getMessage();
    }
}
?>