import { planDmMessageSend } from './dm-message-send.rules';

function makeFile(name: string): File {
  return new File(['x'], name, { type: 'image/png' });
}

describe('planDmMessageSend', () => {
  it('binds attachments to the same pre-allocated message id', () => {
    const generateId = () => 'dm-msg-1';
    const plan = planDmMessageSend({
      generateId,
      content: 'hello',
      pendingFiles: [makeFile('a.png'), makeFile('b.png')]
    });

    expect(plan.action.id).toBe('dm-msg-1');
    expect(plan.attachmentBinding?.messageId).toBe('dm-msg-1');
    expect(plan.attachmentBinding?.files).toHaveLength(2);
  });

  it('returns no attachment binding when there are no pending files', () => {
    const plan = planDmMessageSend({
      generateId: () => 'dm-msg-2',
      content: 'text only',
      pendingFiles: []
    });

    expect(plan.attachmentBinding).toBeNull();
  });
});