import { useCallback, useState } from "react";
import { WEBSOCKET_URL } from "../background/constants";

function useWebSocketConnection() {

  const createWebSocketConnection = () => {
    const webSocket = new WebSocket(WEBSOCKET_URL);
    return webSocket
  }

  const [webSocketConnection] = useState<WebSocket>(createWebSocketConnection())

  const sendMessage = useCallback((message: string) => {
    //if the socket's open, send a message:
    if (webSocketConnection.readyState === WebSocket.OPEN) {
      webSocketConnection.send(message);
    }
  },
    [webSocketConnection]
  )

  const onMessage = useCallback(
    (messageHandler: (messageHandler: string) => void) => {
      const wsMessageHandler = (ev: MessageEvent<any>) => { messageHandler(ev.data) }
      webSocketConnection.addEventListener('message', wsMessageHandler)
    },
    [webSocketConnection]
  )

  return { onMessage, sendMessage }
}

export default useWebSocketConnection;