summaryrefslogtreecommitdiffstats
path: root/testing/web-platform/tests/tools/third_party/websockets/example/tutorial/step1/main.js
blob: dd28f9a6a8bb682356d53f4c3f1d5ef4d1d56ba2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
import { createBoard, playMove } from "./connect4.js";

function showMessage(message) {
  window.setTimeout(() => window.alert(message), 50);
}

function receiveMoves(board, websocket) {
  websocket.addEventListener("message", ({ data }) => {
    const event = JSON.parse(data);
    switch (event.type) {
      case "play":
        // Update the UI with the move.
        playMove(board, event.player, event.column, event.row);
        break;
      case "win":
        showMessage(`Player ${event.player} wins!`);
        // No further messages are expected; close the WebSocket connection.
        websocket.close(1000);
        break;
      case "error":
        showMessage(event.message);
        break;
      default:
        throw new Error(`Unsupported event type: ${event.type}.`);
    }
  });
}

function sendMoves(board, websocket) {
  // When clicking a column, send a "play" event for a move in that column.
  board.addEventListener("click", ({ target }) => {
    const column = target.dataset.column;
    // Ignore clicks outside a column.
    if (column === undefined) {
      return;
    }
    const event = {
      type: "play",
      column: parseInt(column, 10),
    };
    websocket.send(JSON.stringify(event));
  });
}

window.addEventListener("DOMContentLoaded", () => {
  // Initialize the UI.
  const board = document.querySelector(".board");
  createBoard(board);
  // Open the WebSocket connection and register event handlers.
  const websocket = new WebSocket("ws://localhost:8001/");
  receiveMoves(board, websocket);
  sendMoves(board, websocket);
});