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import { Scheduler } from '../src/scheduler';
describe('scheduler', () => {  it('should process event only once', () => {    let calledCount = 0;    const scheduler = new Scheduler();    scheduler.initialize(); // TODO: refactor (use .start())    scheduler.schedule(() => {      calledCount++;    });
    const expectedCount = 1;    expect(calledCount).toEqual(expectedCount);  });
  it('should process more than one event', () => {    let calledCount = 0;    const scheduler = new Scheduler();    scheduler.initialize(); // TODO: refactor (use .start())    scheduler.schedule(() => {      calledCount++;      scheduler.schedule(() => {        calledCount++;      });    });
    const expectedCount = 2;    expect(calledCount).toEqual(expectedCount);  });
  it('should process events in the same order they were hit', () => {    const order: number[] = [];    const scheduler = new Scheduler();    scheduler.initialize(); // TODO: refactor (use .start())    scheduler.schedule(() => {      order.push(1);      scheduler.schedule(() => {        order.push(2);      });      scheduler.schedule(() => {        order.push(3);        scheduler.schedule(() => {          order.push(5);        });      });      scheduler.schedule(() => {        order.push(4);      });    });
    const expectedOrder = [1, 2, 3, 4, 5];    expect(order.length).toEqual(expectedOrder.length);    for (let i = 0; i < expectedOrder.length; i++) {      expect(order[i]).toEqual(expectedOrder[i]);    }  });
  it('should recover if error is thrown while processing event', () => {    let calledCount = 0;    const scheduler = new Scheduler();    scheduler.initialize(); // TODO: refactor (use .start())    expect(() =>      scheduler.schedule(() => {        calledCount++;        throw Error('Test');      })    ).toThrowErrorMatchingInlineSnapshot(`"Test"`);    scheduler.schedule(() => {      calledCount++;    });
    const expectedCount = 2;    expect(calledCount).toEqual(expectedCount);  });
  it('should recover if error is thrown while processing the queue', () => {    let calledCount = 0;    const scheduler = new Scheduler();    scheduler.initialize(); // TODO: refactor (use .start())    expect(() =>      scheduler.schedule(() => {        calledCount++;        scheduler.schedule(() => {          calledCount++;          throw Error('Test');        });      })    ).toThrowErrorMatchingInlineSnapshot(`"Test"`);    scheduler.schedule(() => {      calledCount++;    });
    const expectedCount = 3;    expect(calledCount).toEqual(expectedCount);  });
  it('should stop processing events if error condition is met', () => {    let calledCount = 0;    const scheduler = new Scheduler();    scheduler.initialize(); // TODO: refactor (use .start())    expect(() =>      scheduler.schedule(() => {        calledCount++;        scheduler.schedule(() => {          calledCount++;          throw Error('Test');        });        scheduler.schedule(() => {          calledCount++;        });      })    ).toThrowErrorMatchingInlineSnapshot(`"Test"`);
    const expectedCount = 2;    expect(calledCount).toEqual(expectedCount);  });
  it('should discard not processed events in the case of error condition', () => {    let calledCount = 0;    const scheduler = new Scheduler();    scheduler.initialize(); // TODO: refactor (use .start())    expect(() =>      scheduler.schedule(() => {        calledCount++;        scheduler.schedule(() => {          calledCount++;          throw Error('Test');        });        scheduler.schedule(() => {          calledCount++;        });      })    ).toThrowErrorMatchingInlineSnapshot(`"Test"`);    scheduler.schedule(() => {      calledCount++;    });
    const expectedCount = 3;    expect(calledCount).toEqual(expectedCount);  });
  describe('deferred events', () => {    it('should be able to defer events', () => {      let calledCount = 0;      const scheduler = new Scheduler({        deferEvents: true      });      scheduler.schedule(() => {        calledCount++;      });
      const expectedCount = 0;      expect(calledCount).toEqual(expectedCount);      scheduler.initialize(); // TODO: refactor (use .start())      const expectedFinalCount = 1;      expect(calledCount).toEqual(expectedFinalCount);    });
    it('should process initialization before other events', () => {      const callOrder: number[] = [];      const scheduler = new Scheduler({        deferEvents: true      });      scheduler.schedule(() => {        callOrder.push(2);      });      scheduler.schedule(() => {        callOrder.push(3);      });      scheduler.initialize(() => {        callOrder.push(1);      });
      const expectedOrder = [1, 2, 3];      expect(callOrder.length).toEqual(expectedOrder.length);      for (let i = 0; i < expectedOrder.length; i++) {        expect(callOrder[i]).toEqual(expectedOrder[i]);      }    });
    it('should not defer events after initialization', () => {      const scheduler = new Scheduler({        deferEvents: true      });      scheduler.initialize(); // TODO: refactor (use .start())      let calledCount = 0;      scheduler.schedule(() => {        calledCount++;      });
      const expectedCount = 1;      expect(calledCount).toEqual(expectedCount);    });  });});