<?php
$error = false;
$message = $errorUsername = $errorEmail = $errorPassword = "";

if (isset($_POST['submit'])) {

    // Check username criteria
    if (empty($_POST['username'])) {
        $errorUsername .= "No username written! ";
        $error = true;

    } else {
        if (!preg_match('/^[A-Za-z][A-Za-z0-9]*(?:_[A-Za-z0-9]+)*$/', $_POST['username'])) {
            $errorUsername .= "Not a valid username! ";
            $error = true;
        } else {
            $username = htmlentities($_POST['username']);

            // Checks if username is atleast 3 characters
            if (strlen($username) < 3) {
                $errorUsername .= "The username is too short. Minimum 3 characters! ";
                $error = true;

                // Checks if username is too long
            } else if (strlen($username) > 32) {
                $errorUsername .= "The username is too long. Maximum 32 characters! ";
                $error = true;

            } else {
                try {
                    $stmt = $db->prepare("SELECT username FROM users WHERE username=:username");
                    $stmt->bindParam(":username", $username, PDO::PARAM_STR);
                    $stmt->execute();

                    // Checks if username exists in the database
                    if ($stmt->rowCount() > 0) {
                        $errorUsername .= "That username is already taken! ";
                        $error = true;
                    }
                } catch (PDOException $e) {
                    echo $e->getMessage() . PHP_EOL;
                    $error = true;
                }
            }
        }
    }

    // Checks if email is typed
    if (empty($_POST['email'])) {
        $errorEmail .= "No email written! ";
        $error = true;

    } else {
        $email = htmlentities($_POST['email']);

        // Checks if email is a valid email
        if (!(filter_var($email, FILTER_VALIDATE_EMAIL) && preg_match('/@.+\./', $email))) {
            $errorEmail .= "Not a valid email address! ";
            $error = true;

        } else {
            try {
                $stmt = $db->prepare("SELECT email FROM users WHERE email=:email");
                $stmt->bindParam(":email", $email, PDO::PARAM_STR);
                $stmt->execute();

                // Checks if email exists in database
                if ($stmt->rowCount() > 0) {
                    $errorEmail .= "That email address is already in use! ";
                    $error = true;
                }
            } catch (PDOException $e) {
                echo $e->getMessage();
                $error = true;
            }
        }
    }

    // Checks if password is typed
    if (empty($_POST['password'])) {
        $errorPassword .= "No password written! ";
        $error = true;

    } else {
        // Checks if second password is typed
        if (empty($_POST['passwordConfirm'])) {
            $errorPassword .= "No confirmed password written! ";
            $error = true;
        }

        // Checks if passwords match
        if ($_POST['password'] != $_POST['passwordConfirm']) {
            $errorPassword .= "Passwords does not match! ";
            $error = true;

        // Checks if password is atleast 8 characters
        } else if (strlen($_POST['password']) <= 8) {
            $errorPassword .= "Password is too short. Minimum 8 characters! ";
            $error = true;
        }

    }


    // Now we can create user and do the query!
    if (!$error) {
        // Hashes the password
        $password = password_hash($_POST['password'], PASSWORD_DEFAULT);
        // Create date (1992-05-14)
        $date = date("Y-m-d");

        echo $username . "<br />";
        echo $email . "<br />";
        echo $password . "<br />";
        echo $date . "<br />";

        try {
            $stmt = $db->prepare("INSERT INTO users (username, email, password, created) VALUES (:username, :email, :password, :created)");
            $stmt->bindParam(":username", $username, PDO::PARAM_STR);
            $stmt->bindParam(":email", $email, PDO::PARAM_STR);
            $stmt->bindParam(":password", $password, PDO::PARAM_STR);
            $stmt->bindParam(":created", $date, PDO::PARAM_STR);
            $stmt->execute();

            $message .= "User is made!";
        } catch (PDOException $e) {
            echo $e->getMessage() . PHP_EOL;
        }
    }

}



?>

<ul>
    <?php if (!$_SESSION['user']) { ?>
        <li><a href="index.php">Home</a></li>
        <li><a href="login.php">Login</a></li>
    <?php } else { ?>
        <li><a href="index.php">Home</a></li>
        <li><a href="logout.php">Logout</a></li>
    <?php } ?>
</ul>

<form action="register.php" method="post" name="register">

    <table>
        <tr>
            <td>Username</td>
            <td>
                <input type="text" name="username" value="<?php if (isset($_POST['username'])) echo htmlentities($_POST['username']); ?>">
            </td>
            <td style="color:red;">
                <?php if (!empty($errorUsername)) { echo $errorUsername; } ?>
            </td>
        </tr>
        <tr>
            <td>Email</td>
            <td>
                <input type="email" name="email" value="<?php if (isset($_POST['email'])) echo htmlentities($_POST['email']); ?>">
            </td>
            <td style="color:red;">
                <?php if (!empty($errorEmail)) { echo $errorEmail; } ?>
            </td>
        </tr>
        <tr>
            <td>Password</td>
            <td>
                <input type="password" name="password">
            </td>
            <td style="color:red;">
                <?php if (!empty($errorPassword)) { echo $errorPassword; } ?>
            </td>
        </tr><tr>
            <td>Confirm Password</td>
            <td>
                <input type="password" name="passwordConfirm">
            </td>
            <td>

            </td>
        </tr>
        <tr>
            <td colspan="2" style="text-align:right;">
                <input type="submit" name="submit" value="Register">
            </td>
            <td style="color:green;">
                <?php if (!empty($message)) { echo $message; } ?>
            </td>
        </tr>
    </table>

</form>