<?php
session_start();

// Redirect if already logged in
if (isset($_SESSION['user_id']) && $_SESSION['role'] === 'instructor') {
    header("Location: dashboard.php");
    exit;
}

// Include database configuration
require_once '../admin/database/db_config.php';

// Initialize variables
$email = '';
$errors = [];
$success = false;

// Handle form submission
if ($_SERVER['REQUEST_METHOD'] === 'POST') {
    // Get form data
    $email = trim($_POST['email']);
    $password = $_POST['password'];
    
    // Validate form data
    if (empty($email)) {
        $errors[] = "Email is required";
    }
    
    if (empty($password)) {
        $errors[] = "Password is required";
    }
    
    // Authenticate user
    if (empty($errors)) {
        $query = "SELECT id, username, email, password, first_name, last_name, role, status, profile_image FROM users WHERE email = ? AND role = 'instructor'";
        $stmt = $conn->prepare($query);
        $stmt->bind_param("s", $email);
        $stmt->execute();
        $result = $stmt->get_result();
        
        if ($result->num_rows === 1) {
            $user = $result->fetch_assoc();
            
            // Verify password
            if (password_verify($password, $user['password'])) {
                // Check if account is active
                if ($user['status'] === 'active') {
                    // Set session variables
                    $_SESSION['user_id'] = $user['id'];
                    $_SESSION['username'] = $user['username'];
                    $_SESSION['email'] = $user['email'];
                    $_SESSION['first_name'] = $user['first_name'];
                    $_SESSION['last_name'] = $user['last_name'];
                    $_SESSION['role'] = $user['role'];
                    $_SESSION['profile_image'] = $user['profile_image'];
                    
                    // Redirect to dashboard
                    header("Location: dashboard.php");
                    exit;
                } elseif ($user['status'] === 'pending') {
                    $errors[] = "Your account is pending approval. Please wait for admin approval.";
                } else {
                    $errors[] = "Your account has been suspended. Please contact the administrator.";
                }
            } else {
                $errors[] = "Invalid email or password";
            }
        } else {
            $errors[] = "Invalid email or password";
        }
    }
}

// Check for success message
if (isset($_SESSION['register_success'])) {
    $success = $_SESSION['register_success'];
    unset($_SESSION['register_success']);
}

// Include header
include '../includes/header.php';
?>

<div class="container py-5">
    <div class="row justify-content-center">
        <div class="col-md-6">
            <div class="card shadow-sm">
                <div class="card-header bg-primary text-white">
                    <h4 class="mb-0">Instructor Login</h4>
                </div>
                <div class="card-body">
                    <?php if ($success): ?>
                        <div class="alert alert-success">
                            <?php echo $success; ?>
                        </div>
                    <?php endif; ?>
                    
                    <?php if (!empty($errors)): ?>
                        <div class="alert alert-danger">
                            <ul class="mb-0">
                                <?php foreach ($errors as $error): ?>
                                    <li><?php echo $error; ?></li>
                                <?php endforeach; ?>
                            </ul>
                        </div>
                    <?php endif; ?>
                    
                    <form method="post" action="">
                        <div class="mb-3">
                            <label for="email" class="form-label">Email</label>
                            <input type="email" class="form-control" id="email" name="email" value="<?php echo htmlspecialchars($email); ?>" required>
                        </div>
                        
                        <div class="mb-3">
                            <label for="password" class="form-label">Password</label>
                            <input type="password" class="form-control" id="password" name="password" required>
                        </div>
                        
                        <div class="mb-3 form-check">
                            <input type="checkbox" class="form-check-input" id="remember" name="remember">
                            <label class="form-check-label" for="remember">Remember me</label>
                        </div>
                        
                        <div class="d-grid gap-2">
                            <button type="submit" class="btn btn-primary">Login</button>
                        </div>
                    </form>
                    
                    <div class="mt-4 text-center">
                        <p>Don't have an account? <a href="register.php">Register as an Instructor</a></p>
                        <p><a href="forgot-password.php">Forgot your password?</a></p>
                    </div>
                </div>
            </div>
        </div>
    </div>
</div>

<?php include '../includes/footer.php'; ?>