/**
 * @module types/nip46
 * @description Type definitions for NIP-46 (Nostr Connect / Remote Signing)
 * @see https://github.com/nostr-protocol/nips/blob/master/46.md
 */

/**
 * NIP-46 remote signing methods
 */
export enum Nip46Method {
  CONNECT = 'connect',
  PING = 'ping',
  GET_PUBLIC_KEY = 'get_public_key',
  SIGN_EVENT = 'sign_event',
  NIP04_ENCRYPT = 'nip04_encrypt',
  NIP04_DECRYPT = 'nip04_decrypt',
  NIP44_ENCRYPT = 'nip44_encrypt',
  NIP44_DECRYPT = 'nip44_decrypt',
  GET_RELAYS = 'get_relays',
}

/**
 * Parsed bunker:// URI
 */
export interface BunkerURI {
  /** Remote signer's public key (hex) */
  remotePubkey: string;
  /** Relay URLs for communication */
  relays: string[];
  /** Optional secret for initial connection */
  secret?: string;
}

/**
 * NIP-46 JSON-RPC request (client -> signer)
 */
export interface Nip46Request {
  id: string;
  method: Nip46Method | string;
  params: string[];
}

/**
 * NIP-46 JSON-RPC response (signer -> client)
 */
export interface Nip46Response {
  id: string;
  result?: string;
  error?: string;
}

/**
 * A NIP-46 session containing the ephemeral keypair and conversation key
 */
export interface Nip46Session {
  /** Client's ephemeral private key (hex) */
  clientSecretKey: string;
  /** Client's ephemeral public key (hex) */
  clientPubkey: string;
  /** Remote signer's public key (hex) */
  remotePubkey: string;
  /** NIP-44 conversation key (derived from ECDH) */
  conversationKey: Uint8Array;
}

/**
 * Public session info (safe to expose; excludes private key and conversation key)
 */
export interface Nip46SessionInfo {
  clientPubkey: string;
  remotePubkey: string;
}

/**
 * Result of validating a bunker:// URI
 */
export interface BunkerValidationResult {
  isValid: boolean;
  error?: string;
  uri?: BunkerURI;
}

// ─── Signer / Server Types ──────────────────────────────────────────────────

/**
 * Callback handlers the consumer provides to the signer.
 * The signer dispatches incoming NIP-46 requests to these handlers.
 * NIP-04 handlers are optional (legacy support).
 */
export interface Nip46SignerHandlers {
  /** Return the signer's public key (hex) */
  getPublicKey: () => string | Promise<string>;
  /** Sign a stringified unsigned event, return the stringified signed event */
  signEvent: (eventJson: string) => string | Promise<string>;
  /** NIP-04 encrypt (legacy, optional) */
  nip04Encrypt?: (pubkey: string, plaintext: string) => string | Promise<string>;
  /** NIP-04 decrypt (legacy, optional) */
  nip04Decrypt?: (pubkey: string, ciphertext: string) => string | Promise<string>;
  /** NIP-44 encrypt */
  nip44Encrypt?: (pubkey: string, plaintext: string) => string | Promise<string>;
  /** NIP-44 decrypt */
  nip44Decrypt?: (pubkey: string, ciphertext: string) => string | Promise<string>;
  /** Return relay map as JSON string */
  getRelays?: () => string | Promise<string>;
}

/**
 * Options for handleSignerRequest
 */
export interface Nip46HandleOptions {
  /** Expected connection secret (from bunker:// URI) */
  secret?: string;
  /** Set of authenticated client pubkeys. Not mutated — check newlyAuthenticated on result. */
  authenticatedClients?: Set<string>;
}

/**
 * Result of handleSignerRequest()
 */
export interface Nip46HandleResult {
  /** The response to send back to the client */
  response: Nip46Response;
  /** If the connect handshake succeeded, this is the client pubkey to add to authenticated set */
  newlyAuthenticated?: string;
}

/**
 * Result of unwrapRequest()
 */
export interface Nip46UnwrapResult {
  /** The decrypted request */
  request: Nip46Request;
  /** The client's pubkey (from event.pubkey) */
  clientPubkey: string;
  /** NIP-44 conversation key (reuse for wrapResponse) */
  conversationKey: Uint8Array;
}