import { Injectable } from '@angular/core';
import { Subject, Observable, Observer } from 'rxjs';

@Injectable()
export class WebsockService {

  constructor() {}
  private ws: WebSocket;

  private subject: Subject<MessageEvent>;

  public connect(url): Observable<MessageEvent>
  {
    if (this.subject)
    {
      this.ws.close();
    }
    this.subject = this.create(url);
    console.log('Successfully connected to: ' + url);
    return this.subject.asObservable()
  }

  public create(url): Subject<MessageEvent>
  {
    this.ws = new WebSocket(url);

    let observable = Observable.create(
      (obs: Observer<MessageEvent>) => {
        this.ws.onmessage = obs.next.bind(obs);
        this.ws.onerror = obs.error.bind(obs);
        this.ws.onclose = obs.complete.bind(obs);

        return this.ws.close.bind(this.ws);
      }
    );

    let observer = {
      next: (data: Object) => {
        if (this.ws.readyState === WebSocket.OPEN)
        {
          this.ws.send(JSON.stringify(data));
        }
      }
    };
    return Subject.create(observer, observable);
  }
}

@Injectable()
export class DashSocketService {

  constructor( private wsService: WebsockService, private globals: Globals)
  {

  }

  public getDashInfoBySocket(filter_hash: string): Observable<Dash>
  {
    return this.wsService.connect(`${this.globals.WS_URL}/ws/channel/${filter_hash}`).pipe(
      map(
        res => {
          return new Dash().deserialize(JSON.parse(res.data));
        }
      )
    )
  }
}