import { Message } from '../Message.js';
import { ClientId, createClientId } from './ClientId.js';
import { SessionConnection } from './SessionConnection.js';

export class SessionClients<
  ServerMessage extends Message<any, any>,
  ClientMessage extends Message<any, any>
> {
  private readonly clients = new Map<
    ClientId,
    SessionConnection<ServerMessage, ClientMessage>
  >();

  get(id: ClientId) {
    return this.clients.get(id) || null;
  }

  /**
   * Ids are issued here and nowhere else. `add` used to accept one, which is how
   * a client could pick its own session id: `SessionServer` passed straight
   * through whatever arrived on the wire.
   */
  add() {
    const client = new SessionConnection<ServerMessage, ClientMessage>(
      createClientId(),
    );

    this.clients.set(client.id, client);
    return client;
  }

  remove(id: ClientId) {
    if (!this.clients.has(id)) {
      return false;
    }

    const client = this.clients.get(id)!;
    this.clients.delete(id);
    client.destroy();
    return true;
  }
}