<?php
    //Start session
    session_start();

    //Include database connection details
    require_once('config.php');

    //Array to store validation errors
    $errmsg_arr = array();

    //Validation error flag
    $errflag = false;

    //Connect to mysql server
    $link = mysql_connect(DB_HOST, DB_USER, DB_PASSWORD);
    if(!$link) {
        die('Failed to connect to server: ' . mysql_error());
    }

    //Select database
    $db = mysql_select_db(DB_DATABASE);
    if(!$db) {
        die("Unable to select database");
    }

    //Function to sanitize values received from the form. Prevents SQL injection
    function clean($str) {
        $str = @trim($str);
        if(get_magic_quotes_gpc()) {
            $str = stripslashes($str);
        }
        return mysql_real_escape_string($str);
    }

    //Sanitize the POST values
    $username = clean($_POST['username']);
    $password = clean($_POST['password']);
    $cpassword = clean($_POST['cpassword']);
    $email = clean($_POST['email']);
    $pin = clean($_POST['pin']);
    $key = clean($_POST['key']);

    //Input Validations
    if($username == '') {
        $errmsg_arr[] = 'Username Missing';
        $errflag = true;
    }
    if($password == '') {
        $errmsg_arr[] = 'Password Missing';
        $errflag = true;
    }
    if($cpassword == '') {
        $errmsg_arr[] = 'Confirm Password Missing';
        $errflag = true;
    }
    if($email == '') {
        $errmsg_arr[] = 'Email Address Missing';
        $errflag = true;
    }
    if($pin == '') {
        $errmsg_arr[] = 'Your 4 Digit Pin is Missing';
        $errflag = true;
    }
    if($key == '') {
        $errmsg_arr[] = 'Your 25 Digit Beta Key is Missing';
        $errflag = true;
    }
    if( strcmp($password, $cpassword) != 0 ) {
        $errmsg_arr[] = 'Your passwords do not match!';
        $errflag = true;
    }

    //Check for duplicate Usernames
    if($username != '') {
        $qry = "SELECT * FROM users WHERE username='$username'";
        $result = mysql_query($qry);
        if($result) {
            if(mysql_num_rows($result) > 0) {
                $errmsg_arr[] = 'Username already in use';
                $errflag = true;
            }
            @mysql_free_result($result);
        }
        else {
            die("Query failed");
        }
    }

    //Check for duplicate Beta Keys
    if($key != '') {
        $qry = "SELECT * FROM beta_keys WHERE keys_used='$key'";
        $result = mysql_query($qry);
        if($result) {
            if(mysql_num_rows($result) > 0) {
                $errmsg_arr[] = 'This Beta Key has already been used';
                $errflag = true;
            }
            @mysql_free_result($result);
        }
        else {
            die("Query failed");
        }
    }

    //Check for duplicate Emails
    if($email != '') {
        $qry = "SELECT * FROM users WHERE email='$email'";
        $result = mysql_query($qry);
        if($result) {
            if(mysql_num_rows($result) > 0) {
                $errmsg_arr[] = 'Email already in use';
                $errflag = true;
            }
            @mysql_free_result($result);
        }
        else {
            die("Query failed");
        }
    }

    //If there are input validations, redirect back to the registration form
    if($errflag) {
        $_SESSION['ERRMSG_ARR'] = $errmsg_arr;
        session_write_close();
        header("location: register.php");
        exit();
    }

    //Create INSERT query
    $qry = "INSERT INTO users(username, password, email, pin, key) VALUES('$username','$password','$email','$pin','$key')";
    $qry = "INSERT INTO beta_keys(keys_used) VALUES('$key')";
    $result = @mysql_query($qry);

    //Create DELETE query
    $qry = ("DELETE FROM beta_keys WHERE keys_new='$key'");
    $result = @mysql_query($qry);

    //Check whether the query was successful or not
    if($result) {
        header("location: register-success.php");
        exit();
    }else {
        die("Query failed");
    }
?>