reinhardt-middleware 0.1.0

// The `User` trait is deprecated in favour of the new `#[model]`-based user macro system.
// Downstream crates still reference it during the transition period.
#![allow(deprecated)]

#[cfg(feature = "sessions")]
use async_trait::async_trait;
#[cfg(feature = "sessions")]
use std::sync::Arc;

#[cfg(feature = "sessions")]
use reinhardt_http::{
	Handler, IsActive, IsAdmin, IsAuthenticated, Middleware, Request, Response, Result,
};

#[cfg(feature = "sessions")]
use reinhardt_auth::session::{SESSION_KEY_USER_ID, SessionStore};
#[cfg(feature = "sessions")]
use reinhardt_auth::{AnonymousUser, AuthenticationBackend, User};

/// Authentication middleware
/// Extracts user information from session and attaches it to request extensions
///
/// This middleware integrates with tower/hyper to provide Django-style authentication
/// for Reinhardt applications. It automatically:
/// - Extracts session ID from cookies
/// - Loads user information from the session store
/// - Attaches user authentication state to request extensions
/// - Supports any authentication backend implementing `AuthenticationBackend`
///
/// # Examples
///
/// Basic usage with in-memory session store:
///
/// ```rust,no_run
/// # #[tokio::main]
/// # async fn main() -> Result<(), Box<dyn std::error::Error>> {
/// use std::sync::Arc;
/// use reinhardt_middleware::AuthenticationMiddleware;
/// use reinhardt_auth::session::InMemorySessionStore;
/// use reinhardt_http::MiddlewareChain;
/// # use reinhardt_http::{Handler, {Request, Response, Result}};
/// # use reinhardt_auth::{AuthenticationBackend, AuthenticationError, User, SimpleUser};
/// # use async_trait::async_trait;
/// # use uuid::Uuid;
/// #
/// # struct MyHandler;
/// # #[async_trait]
/// # impl Handler for MyHandler {
/// #     async fn handle(&self, _request: Request) -> Result<Response> {
/// #         Ok(Response::ok())
/// #     }
/// # }
/// #
/// # // Simple test authentication backend
/// # struct TestAuthBackend;
/// # #[async_trait]
/// # impl AuthenticationBackend for TestAuthBackend {
/// #     async fn authenticate(&self, _request: &Request) -> std::result::Result<Option<Box<dyn User>>, AuthenticationError> {
/// #         Ok(Some(Box::new(SimpleUser {
/// #             id: Uuid::now_v7(),
/// #             username: "testuser".to_string(),
/// #             email: "test@example.com".to_string(),
/// #             is_active: true,
/// #             is_admin: false,
/// #             is_staff: false,
/// #             is_superuser: false,
/// #         })))
/// #     }
/// #     async fn get_user(&self, _user_id: &str) -> std::result::Result<Option<Box<dyn User>>, AuthenticationError> {
/// #         Ok(None)
/// #     }
/// # }
///
/// // Create session store and authentication backend
/// let session_store = Arc::new(InMemorySessionStore::new());
/// let auth_backend = Arc::new(TestAuthBackend);
///
/// // Create authentication middleware
/// let auth_middleware = AuthenticationMiddleware::new(session_store, auth_backend);
///
/// // Wrap your handler with the middleware using MiddlewareChain
/// # let handler = Arc::new(MyHandler);
/// let app = MiddlewareChain::new(handler)
///     .with_middleware(Arc::new(auth_middleware));
/// # Ok(())
/// # }
/// ```
///
/// Accessing authentication state in handlers:
///
/// ```
/// # use reinhardt_http::{Handler, {Request, Response, Result}};
/// # use async_trait::async_trait;
/// struct ProtectedHandler;
///
/// #[async_trait]
/// impl Handler for ProtectedHandler {
///     async fn handle(&self, request: Request) -> Result<Response> {
///         // Extract authentication state from request extensions
///         let is_authenticated: Option<bool> = request.extensions.get();
///         let user_id: Option<String> = request.extensions.get();
///         let is_admin: Option<bool> = request.extensions.get();
///
///         if !is_authenticated.unwrap_or(false) {
///             return Ok(Response::new(hyper::StatusCode::UNAUTHORIZED));
///         }
///
///         Ok(Response::ok().with_body(format!("Welcome user: {:?}", user_id)))
///     }
/// }
/// ```
#[cfg(feature = "sessions")]
pub struct AuthenticationMiddleware<S: SessionStore, A: AuthenticationBackend> {
	session_store: Arc<S>,
	auth_backend: Arc<A>,
}

#[cfg(feature = "sessions")]
impl<S: SessionStore, A: AuthenticationBackend> AuthenticationMiddleware<S, A> {
	/// Create a new authentication middleware
	///
	/// # Arguments
	///
	/// * `session_store` - Session storage backend
	/// * `auth_backend` - Authentication backend for user lookup
	///
	/// # Examples
	///
	/// ```no_run
	/// use std::sync::Arc;
	/// use reinhardt_middleware::AuthenticationMiddleware;
	/// use reinhardt_auth::session::InMemorySessionStore;
	/// # use reinhardt_http::Request;
	/// # use reinhardt_auth::{AuthenticationBackend, AuthenticationError, User, SimpleUser};
	/// # use uuid::Uuid;
	/// #
	/// # // Simple test authentication backend
	/// # struct TestAuthBackend;
	/// # #[async_trait::async_trait]
	/// # impl AuthenticationBackend for TestAuthBackend {
	/// #     async fn authenticate(&self, _request: &Request) -> std::result::Result<Option<Box<dyn User>>, AuthenticationError> {
	/// #         Ok(Some(Box::new(SimpleUser {
	/// #             id: Uuid::now_v7(),
	/// #             username: "testuser".to_string(),
	/// #             email: "test@example.com".to_string(),
	/// #             is_active: true,
	/// #             is_admin: false,
	/// #             is_staff: false,
	/// #             is_superuser: false,
	/// #         })))
	/// #     }
	/// #     async fn get_user(&self, _user_id: &str) -> std::result::Result<Option<Box<dyn User>>, AuthenticationError> {
	/// #         Ok(None)
	/// #     }
	/// # }
	///
	/// let session_store = Arc::new(InMemorySessionStore::new());
	/// let auth_backend = Arc::new(TestAuthBackend);
	/// let middleware = AuthenticationMiddleware::new(session_store, auth_backend);
	/// ```
	pub fn new(session_store: Arc<S>, auth_backend: Arc<A>) -> Self {
		Self {
			session_store,
			auth_backend,
		}
	}

	/// Extract session ID from cookies.
	///
	/// Validates that the session ID is non-empty and well-formed
	/// (UUID format) before returning it.
	fn extract_session_id(&self, request: &Request) -> Option<String> {
		const SESSION_COOKIE_NAME: &str = "sessionid";
		request
			.headers
			.get("cookie")
			.and_then(|v| v.to_str().ok())
			.and_then(|cookies| {
				cookies.split(';').find_map(|cookie| {
					let mut parts = cookie.trim().split('=');
					if parts.next()? == SESSION_COOKIE_NAME {
						Some(parts.next()?.to_string())
					} else {
						None
					}
				})
			})
			.filter(|id| Self::is_valid_session_id(id))
	}

	/// Validate that a session ID is non-empty and well-formed.
	///
	/// Session IDs are expected to be UUIDs (32 hex chars + 4 hyphens = 36 chars).
	/// This prevents accepting arbitrary strings as session identifiers.
	fn is_valid_session_id(id: &str) -> bool {
		if id.is_empty() || id.len() > 128 {
			return false;
		}
		// Validate UUID format (xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx)
		uuid::Uuid::parse_str(id).is_ok()
	}

	/// Get user from session
	async fn get_user_from_session(&self, session_id: &String) -> Option<Box<dyn User>> {
		if let Some(session) = self.session_store.load(session_id).await
			&& let Some(user_id_value) = session.get(SESSION_KEY_USER_ID)
			&& let Some(user_id) = user_id_value.as_str()
			&& let Ok(Some(user)) = self.auth_backend.get_user(user_id).await
		{
			return Some(user);
		}
		None
	}
}

#[cfg(feature = "sessions")]
#[async_trait]
impl<S: SessionStore + 'static, A: AuthenticationBackend + 'static> Middleware
	for AuthenticationMiddleware<S, A>
{
	async fn process(&self, request: Request, next: Arc<dyn Handler>) -> Result<Response> {
		let user: Box<dyn User> = if let Some(ref session_id) = self.extract_session_id(&request) {
			self.get_user_from_session(session_id)
				.await
				.unwrap_or_else(|| Box::new(AnonymousUser))
		} else {
			Box::new(AnonymousUser)
		};

		let is_authenticated = user.is_authenticated();
		let is_admin = user.is_admin();
		let is_active = user.is_active();
		let user_id = user.id();

		// Insert individual values for backward compatibility
		request.extensions.insert(user_id.clone());
		request.extensions.insert(IsAuthenticated(is_authenticated));
		request.extensions.insert(IsAdmin(is_admin));
		request.extensions.insert(IsActive(is_active));

		// Insert AuthState object for CurrentUser and new code
		let auth_state = if is_authenticated {
			AuthState::authenticated(user_id, is_admin, is_active)
		} else {
			AuthState::anonymous()
		};
		request.extensions.insert(auth_state);

		next.handle(request).await
	}
}

// Re-export AuthState from reinhardt-http for backward compatibility.
// AuthState is the canonical type for storing authentication state in extensions.
pub use reinhardt_http::AuthState;

#[cfg(all(test, feature = "sessions"))]
mod tests {
	use super::*;
	use bytes::Bytes;
	use hyper::{HeaderMap, Method, Version};
	use reinhardt_auth::AuthenticationError;
	use reinhardt_auth::SimpleUser;
	use reinhardt_auth::session::{InMemorySessionStore, Session};
	use uuid::Uuid;

	struct TestHandler;

	#[async_trait]
	impl Handler for TestHandler {
		async fn handle(&self, request: Request) -> Result<Response> {
			let user_id: Option<String> = request.extensions.get();
			let is_authenticated = request
				.extensions
				.get::<IsAuthenticated>()
				.map(|v| v.0)
				.unwrap_or(false);

			Ok(Response::ok().with_json(&serde_json::json!({
				"user_id": user_id.unwrap_or_default(),
				"is_authenticated": is_authenticated
			}))?)
		}
	}

	struct TestAuthBackend {
		user: Option<SimpleUser>,
	}

	#[async_trait::async_trait]
	impl AuthenticationBackend for TestAuthBackend {
		async fn authenticate(
			&self,
			_request: &Request,
		) -> std::result::Result<Option<Box<dyn User>>, AuthenticationError> {
			Ok(self
				.user
				.as_ref()
				.map(|u| Box::new(u.clone()) as Box<dyn User>))
		}

		async fn get_user(
			&self,
			_user_id: &str,
		) -> std::result::Result<Option<Box<dyn User>>, AuthenticationError> {
			Ok(self
				.user
				.as_ref()
				.map(|u| Box::new(u.clone()) as Box<dyn User>))
		}
	}

	#[tokio::test]
	async fn test_auth_middleware_with_valid_session() {
		let session_store = Arc::new(InMemorySessionStore::new());
		let user = SimpleUser {
			id: Uuid::now_v7(),
			username: "testuser".to_string(),
			email: "test@example.com".to_string(),
			is_active: true,
			is_admin: false,
			is_staff: false,
			is_superuser: false,
		};
		let auth_backend = Arc::new(TestAuthBackend { user: Some(user) });

		let session_id = session_store.create_session_id();
		let mut session = Session::new();
		session.set(SESSION_KEY_USER_ID, serde_json::json!("user123"));
		session_store.save(&session_id, &session).await;

		let middleware = AuthenticationMiddleware::new(session_store, auth_backend);
		let handler = Arc::new(TestHandler);

		let mut headers = HeaderMap::new();
		headers.insert(
			"cookie",
			format!("sessionid={}", session_id).parse().unwrap(),
		);

		let request = Request::builder()
			.method(Method::GET)
			.uri("/test")
			.version(Version::HTTP_11)
			.headers(headers)
			.body(Bytes::new())
			.build()
			.unwrap();

		let response = middleware.process(request, handler).await.unwrap();
		assert_eq!(response.status, reinhardt_http::Response::ok().status);
	}

	#[tokio::test]
	async fn test_auth_middleware_without_session() {
		let session_store = Arc::new(InMemorySessionStore::new());
		let auth_backend = Arc::new(TestAuthBackend { user: None });

		let middleware = AuthenticationMiddleware::new(session_store, auth_backend);
		let handler = Arc::new(TestHandler);

		let request = Request::builder()
			.method(Method::GET)
			.uri("/test")
			.version(Version::HTTP_11)
			.headers(HeaderMap::new())
			.body(Bytes::new())
			.build()
			.unwrap();

		let response = middleware.process(request, handler).await.unwrap();
		assert_eq!(response.status, reinhardt_http::Response::ok().status);

		let body_str = String::from_utf8(response.body.to_vec()).unwrap();
		assert!(body_str.contains("\"is_authenticated\":false"));
	}

	#[test]
	fn test_auth_state_from_extensions() {
		let extensions = reinhardt_http::Extensions::new();
		extensions.insert("user123".to_string());
		extensions.insert(IsAuthenticated(true));

		let auth_state = AuthState::from_extensions(&extensions);
		assert!(auth_state.is_some());
		assert!(!auth_state.unwrap().is_anonymous());
	}

	#[test]
	fn test_auth_state_is_anonymous() {
		let anon_state = AuthState::anonymous();

		assert!(anon_state.is_anonymous());

		let auth_state = AuthState::authenticated("user123", false, true);

		assert!(!auth_state.is_anonymous());
	}
}