const test = require('node:test');
const assert = require('node:assert/strict');
const { EventEmitter } = require('node:events');

// A stand-in for the MQTT client, so no network is involved.
const clients = [];
const live = require('../lib/printerLive');

live.setConnector((url, options) => {
  const c = new EventEmitter();
  Object.assign(c, {
    url, options, connected: false, reconnecting: false, published: [], ended: false,
    subscribe: (_topic, cb) => cb(null),
    publish: (topic, body) => c.published.push({ topic, body: JSON.parse(body) }),
    end: () => { c.ended = true; },
    reconnect: () => {},
  });
  clients.push(c);
  return c;
});

const report = (print) => Buffer.from(JSON.stringify({ print }));
const printerRow = { id: 1, host: '10.0.0.5', serial: 'SER1', access_code: 'code1' };
const tray = (id, type, colour) => ({ id: String(id), tray_type: type, tray_color: colour, tray_uuid: type ? `U${id}` : '0' });

test('live status merges partial reports, and a tray change syncs spools once', async (t) => {
  t.after(() => live.stopAll());
  const synced = [];
  live.setTraysHandler(async (id, trays) => { synced.push({ id, trays }); return { updated: trays.length }; });
  live.reconcile([printerRow, { id: 2, host: '', serial: 'X', access_code: 'y' }]);
  assert.equal(clients.length, 1, 'a printer missing its address isn’t connected');
  const c = clients[0];
  assert.equal(c.options.password, 'code1');

  c.connected = true;
  c.emit('connect');
  assert.equal(c.published[0].topic, 'device/SER1/request');
  assert.equal(c.published[0].body.pushing.command, 'pushall');

  c.emit('message', 'device/SER1/report', report({
    gcode_state: 'RUNNING', mc_percent: 10, nozzle_temper: 220,
    ams: { ams: [{ id: '0', tray: [tray(0, 'PLA', 'FF0000FF'), tray(1, '', '')] }] },
  }));
  c.emit('message', 'device/SER1/report', report({ mc_percent: 11 }));
  const snap = live.snapshot(1);
  assert.equal(snap.connected, true);
  assert.equal(snap.status.state, 'RUNNING');
  assert.equal(snap.status.progress, 11);
  assert.equal(snap.status.nozzle, 220, 'kept from the earlier report');
  assert.deepEqual(snap.loaded.map((l) => [l.slot, l.empty, l.colour, l.tagged]),
    [[0, false, '#FF0000', true], [1, true, null, false]]);
  assert.equal(JSON.stringify(snap).includes('code1'), false, 'no access code in a snapshot');

  // "Test & sync" asks again and syncs straight away.
  const pending = live.refresh(1, 3000);
  c.emit('message', 'device/SER1/report', report({ ams: { ams: [{ id: '0', tray: [tray(0, 'PLA', 'FF0000FF'), tray(1, '', '')] }] } }));
  const result = await pending;
  assert.equal(result.connected, true);
  assert.equal(result.sync.updated, 2);
  assert.equal(synced.length, 1);
  assert.equal(c.published.at(-1).body.pushing.command, 'pushall');
});

test('a busy printer’s steady reports don’t hold back a spool sync', async (t) => {
  t.mock.timers.enable({ apis: ['setTimeout'] });
  t.after(() => live.stopAll());
  clients.length = 0;
  const synced = [];
  live.setTraysHandler(async (id) => { synced.push(id); return {}; });
  live.reconcile([{ ...printerRow, id: 5, serial: 'SER5' }]);
  const c = clients[0];
  c.connected = true;
  c.emit('connect');
  c.emit('message', 't', report({ ams: { ams: [{ id: '0', tray: [tray(0, 'PLA', 'FF0000FF')] }] } }));
  for (let i = 0; i < 10; i += 1) {
    t.mock.timers.tick(1000);
    c.emit('message', 't', report({ mc_percent: i }));
  }
  assert.equal(synced.length, 1, 'synced once, five seconds after the change');
  // The same trays again change nothing.
  c.emit('message', 't', report({ ams: { ams: [{ id: '0', tray: [tray(0, 'PLA', 'FF0000FF')] }] } }));
  t.mock.timers.tick(6000);
  assert.equal(synced.length, 1);
});

test('the tray feeding the toolhead is worked out from tray_now', (t) => {
  t.after(() => live.stopAll());
  clients.length = 0;
  live.setTraysHandler(async () => ({}));
  live.reconcile([{ ...printerRow, id: 7, serial: 'SER7' }, { ...printerRow, id: 8, serial: 'SER8' }]);
  const [a, b] = clients;
  const units = (ids) => ({ ams: ids.map((id) => ({ id: String(id), tray: [tray(0, 'PLA', 'FF0000FF')] })) });
  // Two AMS units numbered 0 and 1: tray 6 is the second unit's third slot.
  a.emit('message', 't', report({ ams: { ...units([0, 1]), tray_now: '6' } }));
  assert.deepEqual(live.snapshot(7).status.active, { unit: 1, slot: 2 });
  // A later report changing only tray_now still counts.
  a.emit('message', 't', report({ ams: { tray_now: '254' } }));
  assert.deepEqual(live.snapshot(7).status.active, { external: true });
  a.emit('message', 't', report({ ams: { tray_now: '255' } }));
  assert.equal(live.snapshot(7).status.active, null);
  // An AMS lite numbered 16 (as on the A2L): tray 1 is its second slot.
  b.emit('message', 't', report({ ams: { ...units([16]), tray_now: '1' } }));
  assert.deepEqual(live.snapshot(8).status.active, { unit: 16, slot: 1 });
});

test('changing a printer’s code reopens its connection; removing it closes it', () => {
  clients.length = 0;
  live.reconcile([printerRow]);
  live.reconcile([printerRow]);
  assert.equal(clients.length, 1, 'no change, no new connection');
  live.reconcile([{ ...printerRow, access_code: 'code2' }]);
  assert.equal(clients.length, 2);
  assert.equal(clients[0].ended, true);
  live.reconcile([]);
  assert.equal(clients[1].ended, true);
  assert.deepEqual(live.snapshot(1), { live: false });
});