import { expect } from '../framework/expect';
import { describe, test } from '../framework/registry';
import { waitFor } from './wait';

// Events.
// Listeners are registered with `on`, triggered by mutating state, and removed
// with `off`. Callbacks are debounced (~10ms), so the tests wait before asserting.

function sleep(ms: number): Promise<void> {
  return new Promise((resolve) => setTimeout(resolve, ms));
}

describe('Events', () => {
  test('selectionchange fires with the selected ids', async (ctx) => {
    const rect = ctx.penpot.createRectangle();
    ctx.board.appendChild(rect);

    let received: string[] | null = null;
    const listenerId = ctx.penpot.on('selectionchange', (ids) => {
      received = ids;
    });

    ctx.penpot.selection = [rect];
    await waitFor(() => received !== null);
    ctx.penpot.off(listenerId);

    expect(received).not.toBeNull();
    if (received) {
      expect((received as string[]).includes(rect.id)).toBe(true);
    }
  });

  test('shapechange fires when the observed shape changes', async (ctx) => {
    const rect = ctx.penpot.createRectangle();
    ctx.board.appendChild(rect);

    let fired = false;
    const listenerId = ctx.penpot.on(
      'shapechange',
      () => {
        fired = true;
      },
      { shapeId: rect.id },
    );

    rect.name = 'changed-name';
    await waitFor(() => fired);
    ctx.penpot.off(listenerId);

    expect(fired).toBe(true);
  });

  test('off stops further notifications', async (ctx) => {
    const rect = ctx.penpot.createRectangle();
    ctx.board.appendChild(rect);

    let count = 0;
    const listenerId = ctx.penpot.on('selectionchange', () => {
      count += 1;
    });
    ctx.penpot.off(listenerId);

    ctx.penpot.selection = [rect];
    // Asserting a non-event: there is no positive condition to poll for, so
    // give the debounce a fixed window to (not) fire.
    await sleep(150);

    expect(count).toBe(0);
  });

  test('a blank shapeId leaves the other listeners working', async (ctx) => {
    const rect = ctx.penpot.createRectangle();
    ctx.board.appendChild(rect);

    // Listeners are store watches notified by a plain iteration, so one that
    // raises aborts the loop and the listeners after it miss the change.
    const blankListenerId = ctx.penpot.on('shapechange', () => {}, {
      shapeId: '',
    });

    let received: string[] | null = null;
    const listenerId = ctx.penpot.on('selectionchange', (ids) => {
      received = ids;
    });

    ctx.penpot.selection = [rect];
    await waitFor(() => received !== null);
    ctx.penpot.off(listenerId);
    ctx.penpot.off(blankListenerId);

    expect(received).not.toBeNull();
  });

  test('a malformed shapeId is rejected when the listener is registered', (ctx) => {
    expect(() =>
      ctx.penpot.on('shapechange', () => {}, { shapeId: 'not-a-uuid' }),
    ).toThrow();
  });
});