/** Maps a backend error envelope's `error.code` to the client's AuthErrorCode screens. Only codes with a dedicated screen are mapped; anything else falls back to the HTTP-status-derived code via authErrorCodeFromStatus. */ const BACKEND_ERROR_CODE_MAP = { TOKEN_EXPIRED: 'session-expired', INVALID_SIGNATURE: 'invalid-signature', UNAUTHENTICATED: 'unauthorized', FORBIDDEN: 'forbidden', SERVICE_UNAVAILABLE: 'backend-unavailable', }; export function authErrorCodeFromBackendCode(code) { return typeof code === 'string' ? BACKEND_ERROR_CODE_MAP[code] : undefined; } /** Maps a backend HTTP status to the AuthErrorCode screen it should route to. */ export function authErrorCodeFromStatus(status) { switch (status) { case 401: return 'unauthorized'; case 403: return 'forbidden'; case 0: return 'backend-unavailable'; default: return status >= 500 ? 'backend-unavailable' : 'unauthorized'; } }