watchparty/server/test/playstateService.test.ts

// PlaystateService.updatePosition/markPlayed - mocks EmbyClient.fetch
// (not the global fetch it wraps), same isolation style as
// catalogService.test.ts, since this is about what PlaystateService
// itself sends/merges, not EmbyClient's own plumbing (see
// embyClient.test.ts for that).
import { describe, it } from 'node:test';
import assert from 'node:assert/strict';
import { PlaystateService } from '../src/services/PlaystateService';
import { EmbyClient } from '../src/emby/EmbyClient';

/** What a real `GET /Users/{userId}/Items/{itemId}` comes back with -
 *  confirmed directly against a real server that the requesting user's
 *  own UserData is always embedded right on the item like this. */
function itemResponse(userData: Record<string, unknown> | undefined): Response {
  return new Response(JSON.stringify({ Id: 'item1', UserData: userData }), { status: 200 });
}

describe('PlaystateService.updatePosition', () => {
  it('GETs the item, then POSTs UserData with only PlaybackPositionTicks changed - everything else survives untouched', async (t) => {
    const capturedCalls: { path: string; token: string; options: unknown }[] = [];
    t.mock.method(EmbyClient, 'fetch', async (path: string, token: string, options: unknown) => {
      capturedCalls.push({ path, token, options });
      if (capturedCalls.length === 1) {
        return itemResponse({ PlaybackPositionTicks: 0, Played: false, IsFavorite: true, Rating: 9.5, PlayCount: 3 });
      }
      return new Response('{}', { status: 200 });
    });

    await PlaystateService.updatePosition('tok-alice', 'u-alice', 'item1', 12_345_678);

    assert.equal(capturedCalls.length, 2);
    assert.equal(capturedCalls[0]!.path, '/Users/u-alice/Items/item1');
    assert.equal(capturedCalls[0]!.token, 'tok-alice');
    assert.equal(capturedCalls[0]!.options, undefined, 'the GET is a plain fetch, no method/body');

    assert.equal(capturedCalls[1]!.path, '/Users/u-alice/Items/item1/UserData');
    assert.equal(capturedCalls[1]!.token, 'tok-alice');
    const posted = capturedCalls[1]!.options as { method: string; body: Record<string, unknown> };
    assert.equal(posted.method, 'POST');
    // The whole point of fetch-merge-write: a favorite/rating/play count
    // this app never asked to change must come back out exactly as read -
    // guessing wrong here risks actually erasing real user data, not just
    // silently no-op'ing the way the old Progress-endpoint bugs did.
    assert.equal(posted.body.IsFavorite, true);
    assert.equal(posted.body.Rating, 9.5);
    assert.equal(posted.body.PlayCount, 3);
    assert.equal(posted.body.Played, false, 'Played is preserved, not touched by a position-only update');
    assert.equal(posted.body.PlaybackPositionTicks, 12345678, 'only this field actually changes');
  });

  it('rounds a fractional positionTicks (Emby expects an integer)', async (t) => {
    let posted: Record<string, unknown> | undefined;
    t.mock.method(EmbyClient, 'fetch', async (path: string, _token: string, options?: { body?: Record<string, unknown> }) => {
      if (path.endsWith('/UserData')) { posted = options?.body; return new Response('{}', { status: 200 }); }
      return itemResponse({});
    });

    await PlaystateService.updatePosition('tok', 'u1', 'item1', 100.7);

    assert.equal(posted?.PlaybackPositionTicks, 101);
  });

  it('has no existing UserData at all (a never-touched item) - still works, starting from an empty object', async (t) => {
    let posted: Record<string, unknown> | undefined;
    t.mock.method(EmbyClient, 'fetch', async (path: string, _token: string, options?: { body?: Record<string, unknown> }) => {
      if (path.endsWith('/UserData')) { posted = options?.body; return new Response('{}', { status: 200 }); }
      return itemResponse(undefined);
    });

    await assert.doesNotReject(() => PlaystateService.updatePosition('tok', 'u1', 'item1', 5000));
    assert.equal(posted?.PlaybackPositionTicks, 5000);
  });

  it('skips the write entirely if the GET fails - never posts with missing/corrupt data', async (t) => {
    let postCalled = false;
    t.mock.method(EmbyClient, 'fetch', async (path: string) => {
      if (path.endsWith('/UserData')) postCalled = true;
      return new Response('nope', { status: 404 });
    });

    await assert.doesNotReject(() => PlaystateService.updatePosition('tok', 'u1', 'item1', 0));
    assert.equal(postCalled, false, 'a failed read must not be followed by a write built on nothing');
  });

  it('swallows a thrown error instead of rejecting - this runs on a timer with nothing to catch it', async (t) => {
    t.mock.method(EmbyClient, 'fetch', async () => { throw new Error('Emby unreachable'); });

    await assert.doesNotReject(() => PlaystateService.updatePosition('tok', 'u1', 'item1', 0));
  });
});

describe('PlaystateService.markPlayed', () => {
  it('POSTs Played: true and resets PlaybackPositionTicks to 0, preserving other fields', async (t) => {
    let posted: Record<string, unknown> | undefined;
    t.mock.method(EmbyClient, 'fetch', async (path: string, _token: string, options?: { body?: Record<string, unknown> }) => {
      if (path.endsWith('/UserData')) { posted = options?.body; return new Response('{}', { status: 200 }); }
      return itemResponse({ PlaybackPositionTicks: 3_000_000, Played: false, IsFavorite: true });
    });

    await PlaystateService.markPlayed('tok', 'u1', 'item1');

    assert.equal(posted?.Played, true);
    assert.equal(posted?.PlaybackPositionTicks, 0);
    assert.equal(posted?.IsFavorite, true, 'a favorite must survive being marked played');
  });

  it('swallows a thrown error instead of rejecting - this runs from an item-advance path that must never stall on it', async (t) => {
    t.mock.method(EmbyClient, 'fetch', async () => { throw new Error('Emby unreachable'); });

    await assert.doesNotReject(() => PlaystateService.markPlayed('tok', 'u1', 'item1'));
  });
});

describe('PlaystateService logging', () => {
  it('logs both outgoing requests and the final outcome, never the token itself', async (t) => {
    const logged: string[] = [];
    t.mock.method(console, 'log', (line: string) => { logged.push(line); });
    t.mock.method(EmbyClient, 'fetch', async (path: string) => {
      if (path.endsWith('/UserData')) return new Response('{}', { status: 200 });
      return itemResponse({});
    });

    await PlaystateService.updatePosition('super-secret-token', 'u-alice', 'item1', 5_000_000);

    const lines = logged.filter((l) => l.includes('[watchparty:playstate]'));
    assert.ok(lines.some((l) => l.includes('GET') && l.includes('/Users/u-alice/Items/item1')), 'the read must be logged');
    assert.ok(lines.some((l) => l.includes('POST') && l.includes('/Users/u-alice/Items/item1/UserData')), 'the write must be logged');
    assert.ok(lines.some((l) => l.includes('200') && l.includes('ok')), 'the outcome must be logged');
    assert.ok(!lines.some((l) => l.includes('super-secret-token')), 'the token travels as a header, never logged');
  });

  it('logs a non-ok write as FAILED, with its real HTTP status', async (t) => {
    const logged: string[] = [];
    t.mock.method(console, 'log', (line: string) => { logged.push(line); });
    t.mock.method(EmbyClient, 'fetch', async (path: string) => {
      if (path.endsWith('/UserData')) return new Response('bad request', { status: 400 });
      return itemResponse({});
    });

    await PlaystateService.updatePosition('tok', 'u1', 'item1', 0);

    const outcomeLine = logged.find((l) => l.includes('[watchparty:playstate]') && l.includes('400'));
    assert.ok(outcomeLine);
    assert.ok(outcomeLine!.includes('FAILED'));
  });

  it('logs a failed read distinctly, without ever attempting/logging the write', async (t) => {
    const logged: string[] = [];
    t.mock.method(console, 'log', (line: string) => { logged.push(line); });
    t.mock.method(EmbyClient, 'fetch', async () => new Response('not found', { status: 404 }));

    await PlaystateService.updatePosition('tok', 'u1', 'item1', 0);

    const lines = logged.filter((l) => l.includes('[watchparty:playstate]'));
    assert.ok(lines.some((l) => l.includes('404') && l.includes('FAILED')));
    assert.ok(!lines.some((l) => l.includes('POST')), 'no write should even be attempted, let alone logged, once the read failed');
  });
});