1const { Buffer } = require('buffer');
 2
 3let buffer = Buffer.alloc(0);
 4process.stdin.resume();
 5process.stdin.on('data', (data) => {
 6    buffer = Buffer.concat([buffer, data]);
 7    handleData();
 8});
 9process.stdin.on('end', () => {
10    handleData();
11});
12
13function handleData() {
14    if (buffer.length < 4) {
15        return;
16    }
17
18    const length = buffer.readUInt32LE(0);
19    console.log(length);
20    console.log(buffer.toString());
21    if (buffer.length < 4 + length) {
22        return;
23    }
24
25    const bytes = buffer.subarray(4, 4 + length);
26    buffer = buffer.subarray(4 + length);
27
28    try {
29        const message = JSON.parse(bytes);
30        handleMessage(message);
31    } catch (_) {
32        sendResponse(makeError("Request JSON parse error"));
33        return;
34    }
35}
36
37// format
38// clear_cache
39// shutdown
40// error
41
42function handleMessage(message) {
43    console.log(message);
44    sendResponse({ method: "hi", result: null });
45}
46
47function makeError(message) {
48    return { method: "error", message };
49}
50
51function sendResponse(response) {
52    let message = Buffer.from(JSON.stringify(response));
53    let length = Buffer.alloc(4);
54    length.writeUInt32LE(message.length);
55    process.stdout.write(length);
56    process.stdout.write(message);
57}