<?php
ini_set('session.use_strict_mode', 1);
ini_set('session.cookie_lifetime', 0);
ini_set('session.cookie_secure', 1); // Should be 1 in production
ini_set('session.cookie_httponly', 1);
ini_set('session.cookie_samesite', 'Lax');
session_start();

require_once __DIR__ . '/db/config.php';

function is_logged_in() {
    return isset($_SESSION['user_id']);
}

function require_login() {
    if (!is_logged_in()) {
        header('Location: login.php');
        exit;
    }
}

// Handle login
if ($_SERVER['REQUEST_METHOD'] === 'POST' && isset($_POST['email'], $_POST['password'])) {
    $email = $_POST['email'];
    $password = $_POST['password'];

    try {
        $pdo = db();
        $stmt = $pdo->prepare("SELECT * FROM users WHERE email = ?");
        $stmt->execute([$email]);
        $user = $stmt->fetch();

        if ($user && password_verify($password, $user['password'])) {
            session_regenerate_id(true);
            $_SESSION['user_id'] = $user['id'];
            $_SESSION['user_name'] = $user['name'];
            $_SESSION['user_role'] = $user['role'];
            header('Location: index.php');
            exit;
        } else {
            $_SESSION['login_error'] = 'Invalid email or password.';
            header('Location: login.php');
            exit;
        }
    } catch (PDOException $e) {
        // In a real app, log this error.
        $_SESSION['login_error'] = 'An error occurred. Please try again later.';
        header('Location: login.php');
        exit;
    }
}