function getDaysBetweenTwoDates(firstDateInISO, secondDateInISO) {
  const startDate = new Date(firstDateInISO);
  const endDate = new Date(secondDateInISO);

  const firstDate = Date.UTC(
    startDate.getFullYear(),
    startDate.getMonth(),
    startDate.getDate()
  );
  const secondDate = Date.UTC(
    endDate.getFullYear(),
    endDate.getMonth(),
    endDate.getDate()
  );

  return Math.abs(
    (firstDate.valueOf() - secondDate.valueOf()) / (24 * 60 * 60 * 1000)
  );
}

// Assertion below
describe("getDaysBetweenTwoDates", function () {
  it("should calculate days between date from the past to the future", () => {
    expect(
      getDaysBetweenTwoDates(
        "2024-01-04T00:00:00+02:00",
        "2024-07-04T00:00:00+02:00"
      )
    ).toEqual(183);
  });
  
    it("should calculate days between date from the future to the past", () => {
    expect(
      getDaysBetweenTwoDates(
        "2024-07-04T00:00:00+02:00",
        "2024-01-04T00:00:00+02:00"
      )
    ).toEqual(183);
  });
});