<!--Includes HTML, Head, Scripts, CSS, Body and begin of Content div-->
<?php include realpath(__DIR__)."/layout/header.php"; ?>
<?php
    function Validate() {
        if ($_SERVER['REQUEST_METHOD'] === 'POST') {
            return IsValid("username") && IsValid("password") && IsValid("usermail");
        } else {
            return true;
        }
    }
    function IsValid($name) {
        if ($_SERVER['REQUEST_METHOD'] === 'POST') {
            switch($name){
                case 'username':
                    return !isset($_POST["username"]) || strlen($_POST["username"]) > 0;
                    break;
                case 'password':
                    return !isset($_POST["password"]) || strlen($_POST["password"]) > 0;
                    break;
                case 'usermail':
                    return strlen($_POST["usermail"]) > 0 && filter_var($_POST["usermail"], FILTER_VALIDATE_EMAIL);
                    break;
            }
        } else {
            return true;
        }
    }
    function GetErrorMessage($name) {
        if ($_SERVER['REQUEST_METHOD'] === 'POST') {
            switch($name){
                case 'username':
                    return !isset($_POST["username"]) || strlen($_POST["username"]) == 0 ? 'Username is required' : '';
                    break;
                case 'password':
                    return !isset($_POST["username"]) || strlen($_POST["password"]) == 0 ? 'Password is required' : '';
                    break;
                case 'usermail':
                    $message = '';
                    if (strlen($_POST["usermail"]) == 0) {
                        $message = $message.'E-mail is required';
                    }
                    if(strlen($_POST["usermail"]) != 0 && !filter_var($_POST["usermail"], FILTER_VALIDATE_EMAIL)) {
                        if(strlen($message) > 0) {
                            $message = $message.'<br />';
                        }
                        $message = $message.'"'.$_POST["usermail"].'" is not a valid e-mail address';
                    }
                    return $message;
                    break;
            }
        } else {
            return '';
        }
    }
?>
<div class="row">
    <div class="col-md-4">
        <form action="./userform.php" method="POST" role="form">
            <div class="form-group <?php echo IsValid('username') ? '' : 'has-error' ?>">
                <label for="username">Username</label>
                <input type="text" id="username" name="username" class="form-control" value="<?php echo Validate() ? '' : $_POST["username"] ?>" />
                <span class="help-block"><?php echo GetErrorMessage('username') ?></span>
            </div>
            <div class="form-group <?php echo IsValid('password') ? '' : 'has-error' ?>">
                <label for="password">Password</label>
                <input type="password" id="password" name="password" class="form-control" value="<?php echo Validate() ? '' : $_POST["password"] ?>" />
                <span class="help-block"><?php echo GetErrorMessage('password') ?></span>
            </div>
            <div class="form-group <?php echo IsValid('usermail') ? '' : 'has-error' ?>">
                <label for="usermail">E-Mail</label>
                <input type="text" id="usermail" name="usermail" class="form-control" value="<?php echo Validate() ? '' : $_POST["usermail"] ?>" />
                <span class="help-block"><?php echo GetErrorMessage('usermail') ?></span>
            </div>
            <div class="form-group">
                <button type="submit" class="btn btn-default">Submit</button>
            </div>
        </form>
    </div>
    <?php
        if ($_SERVER['REQUEST_METHOD'] === 'POST' && Validate()) {
            echo '<div class="col-md-4"><h4>Data from POST</h4><p>Username: '.$_POST["username"].'</p><p>Password: '.$_POST["password"].'</p><p>E-Mail: '.$_POST["usermail"].'</p></div>';
        } else if($_SERVER['REQUEST_METHOD'] === 'POST' && !Validate()) {
            echo '<div class="col-md-4"><h4>Data from POST is not valid</h4></div>';
        }
    ?>
</div>
<!--Includes End of Content div, Body and HTML-->
<?php include realpath(__DIR__)."/layout/footer.php"; ?>