<?php
require_once 'db/config.php';

header('Content-Type: application/json');

$response = ['success' => false, 'message' => 'An error occurred.'];

if ($_SERVER['REQUEST_METHOD'] === 'POST') {
    $username = $_POST['username'] ?? '';
    $password = $_POST['password'] ?? '';

    if (empty($username) || empty($password)) {
        $response['message'] = 'Username and password are required.';
        echo json_encode($response);
        exit;
    }

    try {
        $pdo = db();

        // Check if username already exists
        $stmt = $pdo->prepare("SELECT id FROM users WHERE username = ?");
        $stmt->execute([$username]);
        if ($stmt->fetch()) {
            $response['message'] = 'Username already taken.';
            echo json_encode($response);
            exit;
        }

        // Hash the password
        $password_hash = password_hash($password, PASSWORD_DEFAULT);

        // Insert the new user
        $stmt = $pdo->prepare("INSERT INTO users (username, password) VALUES (?, ?)");
        if ($stmt->execute([$username, $password_hash])) {
            $response['success'] = true;
            $response['message'] = 'Registration successful. You can now log in.';
        } else {
            $response['message'] = 'Failed to register user.';
        }
    } catch (PDOException $e) {
        // In a real application, you would log this error.
        $response['message'] = 'Database error: ' . $e->getMessage();
    }

    echo json_encode($response);
}
?>