import type { Envelope } from '../protocol';

export interface RoomMetadata {
  maxClients?: number | undefined;
  [key: string]: unknown;
}

export type SignalEnvelope =
  | {
      readonly kind: 'host-register';
      readonly roomName: string;
      readonly metadata?: RoomMetadata | undefined;
      readonly from?: string | undefined;
      readonly ipHash?: string | undefined;
      readonly accessToken?: string | undefined;
    }
  | { readonly kind: 'host-registered'; readonly roomId: string; readonly hostSignalId: string }
  | {
      readonly kind: 'join-request';
      readonly roomName: string;
      readonly roomId?: string | undefined;
      readonly options?: unknown;
      readonly from?: string | undefined;
      readonly ipHash?: string | undefined;
      readonly accessToken?: string | undefined;
    }
  | {
      readonly kind: 'join-routed';
      readonly roomId: string;
      readonly hostSignalId: string;
      readonly clientSignalId: string;
    }
  | {
      readonly kind: 'rtc-offer';
      readonly roomId: string;
      readonly target: string;
      readonly from?: string | undefined;
      readonly ipHash?: string | undefined;
      readonly sdp: RTCSessionDescriptionInit;
    }
  | {
      readonly kind: 'rtc-answer';
      readonly roomId: string;
      readonly target: string;
      readonly from?: string | undefined;
      readonly ipHash?: string | undefined;
      readonly sdp: RTCSessionDescriptionInit;
    }
  | {
      readonly kind: 'rtc-ice';
      readonly roomId: string;
      readonly target: string;
      readonly from?: string | undefined;
      readonly ipHash?: string | undefined;
      readonly candidate: RTCIceCandidateInit;
    }
  | {
      readonly kind: 'relay-open';
      readonly roomId: string;
      readonly target: string;
      readonly from?: string | undefined;
      readonly ipHash?: string | undefined;
    }
  | {
      readonly kind: 'relay-data';
      readonly roomId: string;
      readonly target: string;
      readonly from?: string | undefined;
      readonly ipHash?: string | undefined;
      // The session's managed access token, attached by the forced-relay client
      // transports (`HttpRelayPacketChannel`/`HostRelayPacketChannel`). It is the
      // ONLY trustworthy sender identity a POST relay-data frame carries, so
      // under account enforcement the relay meters bytes against its verified
      // `userId` — never the spoofable `from`. Absent for self-host / BYOK.
      readonly accessToken?: string | undefined;
      readonly envelope: Envelope;
    }
  | { readonly kind: 'relay-drain'; readonly peerId: string }
  | { readonly kind: 'relay-drained'; readonly messages: readonly SignalEnvelope[] }
  | { readonly kind: 'heartbeat'; readonly roomId: string; readonly from?: string | undefined }
  | { readonly kind: 'error'; readonly message: string };