<?php

namespace Web;

require_once __DIR__ . '/Auth.php';

/**
 * AuthMiddleware provides authentication checks for routes
 */
class AuthMiddleware
{
	private Auth $auth;

	public function __construct(Auth $auth)
	{
		$this->auth = $auth;
	}

	/**
	 * Require authentication
	 */
	public function requireAuth(): callable
	{
		return function(Context $context, callable $next) {
			if ($this->auth->guest()) {
				// Check if request expects JSON
				if ($context->request->expectsJson()) {
					$context->json(['error' => 'Unauthenticated'], 401);
					return;
				}

				// Redirect to login page
				$context->redirect('/login');
				return;
			}

			// Add user to context
			$context->set('user', $this->auth->user());
			$next();
		};
	}

	/**
	 * Require guest (not authenticated)
	 */
	public function requireGuest(): callable
	{
		return function(Context $context, callable $next) {
			if ($this->auth->check()) {
				// Check if request expects JSON
				if ($context->request->expectsJson()) {
					$context->json(['error' => 'Already authenticated'], 403);
					return;
				}

				// Redirect to home or dashboard
				$context->redirect('/');
				return;
			}

			$next();
		};
	}

	/**
	 * Optional authentication (sets user if authenticated)
	 */
	public function optional(): callable
	{
		return function(Context $context, callable $next) {
			if ($this->auth->check()) $context->set('user', $this->auth->user());
			$next();
		};
	}

	/**
	 * Check if user has specific role
	 */
	public function requireRole(string|array $roles): callable
	{
		$roles = is_array($roles) ? $roles : [$roles];

		return function(Context $context, callable $next) use ($roles) {
			if ($this->auth->guest()) {
				if ($context->request->expectsJson()) {
					$context->json(['error' => 'Unauthenticated'], 401);
					return;
				}
				$context->redirect('/login');
				return;
			}

			$user = $this->auth->user();
			$userRole = $user->role;

			if (!in_array($userRole, $roles)) {
				if ($context->request->expectsJson()) {
					$context->json(['error' => 'Insufficient permissions'], 403);
					return;
				}
				$context->error(403, 'Forbidden');
				return;
			}

			$context->set('user', $user);
			$next();
		};
	}

	/**
	 * Rate limiting per user
	 */
	public function rateLimit(int $maxAttempts = 60, int $decayMinutes = 1): callable
	{
		return function(Context $context, callable $next) use ($maxAttempts, $decayMinutes) {
			if ($this->auth->guest()) {
				$identifier = $context->request->ip();
			} else {
				$identifier = 'user:' . $this->auth->id();
			}

			$key = 'rate_limit:' . $identifier . ':' . $context->request->path;
			$attempts = $context->session->get($key, 0);
			$resetTime = $context->session->get($key . ':reset', 0);

			// Reset counter if decay time has passed
			if (time() > $resetTime) {
				$attempts = 0;
				$context->session->set($key . ':reset', time() + ($decayMinutes * 60));
			}

			if ($attempts >= $maxAttempts) {
				$retryAfter = $resetTime - time();
				$context->response->header('X-RateLimit-Limit', (string)$maxAttempts);
				$context->response->header('X-RateLimit-Remaining', '0');
				$context->response->header('Retry-After', (string)$retryAfter);

				if ($context->request->expectsJson()) {
					$context->json([
						'error' => 'Too many requests',
						'retry_after' => $retryAfter
					], 429);
					return;
				}

				$context->error(429, 'Too Many Requests');
				return;
			}

			// Increment attempts
			$context->session->set($key, $attempts + 1);

			// Add rate limit headers
			$context->response->header('X-RateLimit-Limit', (string)$maxAttempts);
			$context->response->header('X-RateLimit-Remaining', (string)($maxAttempts - $attempts - 1));

			$next();
		};
	}

	/**
	 * CSRF protection
	 */
	public function verifyCsrf(): callable
	{
		return function(Context $context, callable $next) {
			// Skip CSRF for safe methods
			if (in_array($context->request->method, ['GET', 'HEAD', 'OPTIONS'])) {
				$next();
				return;
			}

			$token = $context->request->input('_token')
				?? $context->request->header('X-CSRF-TOKEN')
				?? $context->request->header('X-XSRF-TOKEN');

			if (!$context->session->validateCsrf($token)) {
				if ($context->request->expectsJson()) {
					$context->json(['error' => 'CSRF token mismatch'], 419);
					return;
				}
				$context->error(419, 'CSRF token mismatch');
				return;
			}

			$next();
		};
	}

	/**
	 * Remember user from cookie
	 */
	public function remember(): callable
	{
		return function(Context $context, callable $next) {
			// Auth class already handles remember cookies in constructor
			// This middleware can be used to refresh the remember token if needed

			if ($this->auth->check()) {
				$context->set('user', $this->auth->user());
			}

			$next();
		};
	}
}