app.component.ts

import { Component, OnInit } from '@angular/core';
import { AppService } from './app.service';

@Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.scss'],
})
export class AppComponent implements OnInit {
  currency = '';
  currencies;
  tickCount = 0;
  pipDiff = 0;
  buyOrSell = '';
  ticker = 0;
  movavg = 0;
  webSocket;
  averages;

  constructor(private appService: AppService) {}

  ngOnInit(): void {
    this.appService.getCcyPair().subscribe((data: Array<any>) => {
      this.currencies = data.map((d) => d['currency_name']);
      this.currency = this.currencies[0];
    });
  }
  
    handleSubmit() {
    this.wsSend({
      currencyPair: this.currency,
    });
  }

  wsSend(message) {
    if (this.webSocket) {
      this.webSocket.close();
    }
    this.averages = [];
    const messageValue = JSON.stringify(message);
    this.webSocket = this.initializeWS(messageValue);
  }
      
      initializeWS(message) {
    const webSocket = new WebSocket('wss://stocksimulator.coderiq.io');

    webSocket.onopen = (evt) => {
      console.log('Connected to WebSocket...');
      webSocket.send(message);
      console.log('SENT: ' + message);
    };

    webSocket.onclose = (evt) => {
      console.log('Disconnected from WebSocket...');
    };

    webSocket.onerror = (evt) => {
      console.log('Error in WebSocket: ');
    };

    function getAvg(arr): number {
      let sum = 0;
      for (var i = 0; i < arr.length; i++) {
        sum += parseFloat(arr[i]); //don't forget to add the base
      }

      const avg = Number(sum / arr.length);
      return Math.round(avg * 10000) / 10000;
    }

    webSocket.onmessage = (evt) => {
      console.log('message');

      const pipDiff = this.pipDiff;
      const tickCount = this.tickCount - 1;
      const averages = this.averages.slice(-1 * tickCount);
      averages.push(evt.data);

      if (averages.length >= tickCount) {
        const avg = getAvg(averages);
        const price = Math.round(evt.data * 10000) / 10000;
        const diff = (avg - price) * 10000;
        let buyOrSell = '';

        if (Math.abs(diff) > pipDiff) {
          if (price > avg) {
            buyOrSell = 'SELL';
          } else {
            buyOrSell = 'BUY';
          }
        } else {
          buyOrSell = '';
        }

        this.movavg = avg;
        this.ticker = price;
        this.buyOrSell = buyOrSell;
        console.log(this.movavg, this.ticker, this.buyOrSell);
      }

      this.averages = averages;
    };
    return webSocket;
  }
}