export const YONEXUS_PROTOCOL_VERSION = "1" as const;

export const builtinMessageTypes = [
  "hello",
  "hello_ack",
  "pair_request",
  "pair_confirm",
  "pair_success",
  "pair_failed",
  "auth_request",
  "auth_success",
  "auth_failed",
  "re_pair_required",
  "heartbeat",
  "heartbeat_ack",
  "status_update",
  "disconnect_notice",
  "error"
] as const;

export type BuiltinMessageType = (typeof builtinMessageTypes)[number];

export interface BuiltinEnvelope<
  TType extends BuiltinMessageType = BuiltinMessageType,
  TPayload extends Record<string, unknown> = Record<string, unknown>
> {
  type: TType;
  requestId?: string;
  timestamp?: number;
  payload?: TPayload;
}

export interface HelloPayload {
  identifier: string;
  hasSecret: boolean;
  hasKeyPair: boolean;
  publicKey?: string;
  protocolVersion: string;
}

export type HelloAckNextAction =
  | "pair_required"
  | "auth_required"
  | "rejected"
  | "waiting_pair_confirm";

export interface HelloAckPayload {
  identifier: string;
  nextAction: HelloAckNextAction;
}

export type AdminNotificationStatus = "sent" | "failed";

export interface PairRequestPayload {
  identifier: string;
  expiresAt: number;
  ttlSeconds: number;
  adminNotification: AdminNotificationStatus;
  codeDelivery: "out_of_band";
}

export interface PairConfirmPayload {
  identifier: string;
  pairingCode: string;
}

export interface PairSuccessPayload {
  identifier: string;
  secret: string;
  pairedAt: number;
}

export type PairFailedReason =
  | "expired"
  | "invalid_code"
  | "identifier_not_allowed"
  | "admin_notification_failed"
  | "internal_error";

export interface PairFailedPayload {
  identifier: string;
  reason: PairFailedReason;
}

export interface AuthRequestPayload {
  identifier: string;
  nonce: string;
  proofTimestamp: number;
  signature: string;
  publicKey?: string;
}

export interface AuthSuccessPayload {
  identifier: string;
  authenticatedAt: number;
  status: "online";
}

export type AuthFailedReason =
  | "unknown_identifier"
  | "not_paired"
  | "invalid_signature"
  | "invalid_secret"
  | "stale_timestamp"
  | "future_timestamp"
  | "nonce_collision"
  | "rate_limited"
  | "re_pair_required";

export interface AuthFailedPayload {
  identifier: string;
  reason: AuthFailedReason;
}

export interface RePairRequiredPayload {
  identifier: string;
  reason: "nonce_collision" | "rate_limited" | "trust_revoked";
}

export interface HeartbeatPayload {
  identifier: string;
  status: "alive";
}

export interface HeartbeatAckPayload {
  identifier: string;
  status: "online" | "unstable" | "offline";
}

export interface StatusUpdatePayload {
  identifier: string;
  status: "online" | "unstable" | "offline";
  reason: string;
}

export interface DisconnectNoticePayload {
  identifier: string;
  reason: string;
}

export type ProtocolErrorCode =
  | "MALFORMED_MESSAGE"
  | "UNSUPPORTED_PROTOCOL_VERSION"
  | "IDENTIFIER_NOT_ALLOWED"
  | "PAIRING_REQUIRED"
  | "PAIRING_EXPIRED"
  | "ADMIN_NOTIFICATION_FAILED"
  | "AUTH_FAILED"
  | "NONCE_COLLISION"
  | "RATE_LIMITED"
  | "RE_PAIR_REQUIRED"
  | "CLIENT_OFFLINE"
  | "INTERNAL_ERROR";

export interface ErrorPayload {
  code: ProtocolErrorCode;
  message?: string;
  details?: Record<string, unknown>;
}

export type BuiltinPayloadMap = {
  hello: HelloPayload;
  hello_ack: HelloAckPayload;
  pair_request: PairRequestPayload;
  pair_confirm: PairConfirmPayload;
  pair_success: PairSuccessPayload;
  pair_failed: PairFailedPayload;
  auth_request: AuthRequestPayload;
  auth_success: AuthSuccessPayload;
  auth_failed: AuthFailedPayload;
  re_pair_required: RePairRequiredPayload;
  heartbeat: HeartbeatPayload;
  heartbeat_ack: HeartbeatAckPayload;
  status_update: StatusUpdatePayload;
  disconnect_notice: DisconnectNoticePayload;
  error: ErrorPayload;
};

export type TypedBuiltinEnvelope<TType extends keyof BuiltinPayloadMap> = BuiltinEnvelope<
  TType,
  BuiltinPayloadMap[TType]
>;