import { test } from 'node:test';
import assert from 'node:assert/strict';
import { NotificationCountType, ReceiptType } from 'matrix-js-sdk';
import { markAsRead } from './notifications';

// markAsRead sends an unthreaded read receipt at the latest main-timeline event,
// plus a THREADED receipt at each unread thread's latest loaded reply. The
// regression these tests guard against: a thread whose replies aren't loaded
// (lastReply() === null) must NOT produce a receipt for the thread root — that
// resolves to a MAIN receipt at an old event and permanently unreads the room.

type ReceiptCall = { eventId: string; receiptType: ReceiptType; unthreaded?: boolean };

const evt = (id: string, sending = false) => ({ getId: () => id, isSending: () => sending }) as any;

const thread = (id: string, lastReply: any) => ({ id, lastReply: () => lastReply }) as any;

type RoomOpts = {
  timeline?: any[];
  readUpTo?: string | null;
  threads?: any[];
  threadUnread?: Record<string, number>;
};

const setup = (opts: RoomOpts) => {
  const calls: ReceiptCall[] = [];
  const room = {
    getLiveTimeline: () => ({ getEvents: () => opts.timeline ?? [] }),
    getEventReadUpTo: () => opts.readUpTo ?? null,
    getThreads: () => opts.threads ?? [],
    getThreadUnreadNotificationCount: (threadId: string, _type: NotificationCountType) =>
      opts.threadUnread?.[threadId] ?? 0,
  };
  const mx = {
    getRoom: () => room,
    getUserId: () => '@me:server',
    sendReadReceipt: async (event: any, receiptType: ReceiptType, unthreaded?: boolean) => {
      calls.push({ eventId: event.getId(), receiptType, unthreaded });
      return {};
    },
  } as any;
  return { mx, calls };
};

test('main timeline: unthreaded receipt at the latest event', async () => {
  const { mx, calls } = setup({ timeline: [evt('a'), evt('b'), evt('c')], readUpTo: 'a' });
  await markAsRead(mx, '!r:server', false);
  assert.equal(calls.length, 1);
  assert.deepEqual(calls[0], { eventId: 'c', receiptType: ReceiptType.Read, unthreaded: true });
});

test('REGRESSION: an unread thread with unloaded replies (lastReply null) sends NO root receipt', async () => {
  const t = thread('$root', null); // replies not loaded
  const { mx, calls } = setup({
    timeline: [evt('a'), evt('b')],
    readUpTo: 'a',
    threads: [t],
    threadUnread: { $root: 3 },
  });
  await markAsRead(mx, '!r:server', false);
  // Only the main unthreaded receipt — never a receipt for the thread root.
  assert.equal(calls.length, 1);
  assert.equal(calls[0].eventId, 'b');
  assert.equal(calls[0].unthreaded, true);
  assert.ok(!calls.some((c) => c.eventId === '$root'));
});

test('unread thread with a loaded reply sends a threaded receipt at that reply', async () => {
  const t = thread('$root', evt('$reply'));
  const { mx, calls } = setup({
    timeline: [evt('a'), evt('b')],
    readUpTo: 'a',
    threads: [t],
    threadUnread: { $root: 1 },
  });
  await markAsRead(mx, '!r:server', false);
  const main = calls.find((c) => c.eventId === 'b');
  const threaded = calls.find((c) => c.eventId === '$reply');
  assert.ok(main && main.unthreaded === true);
  assert.ok(threaded && threaded.unthreaded === false);
  assert.equal(calls.length, 2);
});

test('main already read but a thread is unread: no main receipt, threaded receipt only', async () => {
  const t = thread('$root', evt('$reply'));
  const { mx, calls } = setup({
    timeline: [evt('a'), evt('b')],
    readUpTo: 'b', // latest main event already read → getLatestValidEvent() null
    threads: [t],
    threadUnread: { $root: 2 },
  });
  await markAsRead(mx, '!r:server', false);
  assert.equal(calls.length, 1);
  assert.equal(calls[0].eventId, '$reply');
  assert.equal(calls[0].unthreaded, false);
});

test('everything read: no receipts sent', async () => {
  const t = thread('$root', evt('$reply'));
  const { mx, calls } = setup({
    timeline: [evt('a'), evt('b')],
    readUpTo: 'b',
    threads: [t],
    threadUnread: { $root: 0 }, // thread read too
  });
  await markAsRead(mx, '!r:server', false);
  assert.equal(calls.length, 0);
});

test('sending thread reply is skipped', async () => {
  const t = thread('$root', evt('$reply', true)); // isSending → skip
  const { mx, calls } = setup({
    timeline: [evt('a'), evt('b')],
    readUpTo: 'b',
    threads: [t],
    threadUnread: { $root: 1 },
  });
  await markAsRead(mx, '!r:server', false);
  assert.equal(calls.length, 0);
});

test('private receipt flag uses ReadPrivate', async () => {
  const { mx, calls } = setup({ timeline: [evt('a'), evt('b')], readUpTo: 'a' });
  await markAsRead(mx, '!r:server', true);
  assert.equal(calls[0].receiptType, ReceiptType.ReadPrivate);
});