import {
  ConnectionLifecycle,
  ConnectionStatus,
  ConnectionStatusListener,
  OnConnectionStatusChangeResponse,
} from '@ably/chat';
import { ErrorInfo } from 'ably';
import { nanoid } from 'nanoid';

import { jsonRpcBlocking, registerCallback } from './jsonrpc';

export class RpcConnectionStatus implements ConnectionStatus {
  private readonly _instanceId: string;

  constructor(instanceId: string) {
    this._instanceId = instanceId;
  }

  get current(): ConnectionLifecycle {
    const { response } = jsonRpcBlocking.request('ConnectionStatus#current', { refId: this._instanceId });
    return response;
  }

  get error(): ErrorInfo | undefined {
    const { response } = jsonRpcBlocking.request('ConnectionStatus#error', { refId: this._instanceId });
    return response;
  }

  onChange(listener: ConnectionStatusListener): OnConnectionStatusChangeResponse {
    const callbackId = nanoid();

    registerCallback(callbackId, listener);
    const { refId } = jsonRpcBlocking.request('ConnectionStatus.onChange', {
      refId: this._instanceId,
      callbackId,
    });
    return new RpcOnConnectionStatusChangeResponse(refId);
  }

  offAll(): void {
    jsonRpcBlocking.request('ConnectionStatus.offAll', { refId: this._instanceId });
  }
}

export class RpcOnConnectionStatusChangeResponse implements OnConnectionStatusChangeResponse {
  private readonly _instanceId: string;

  constructor(instanceId: string) {
    this._instanceId = instanceId;

    // it is common to destructure this object when received from the subscription function,
    // so we need to bind its functions to preserve reference to this
    this.off = this.off.bind(this);
  }

  off(): void {
    jsonRpcBlocking.request('OnConnectionStatusChangeResponse.off', { refId: this._instanceId });
  }
}