Terminal.Gui/UnitTests/Views/DatePickerTests.cs

using System;
using System.Globalization;
using Xunit;

namespace Terminal.Gui.ViewsTests;

public class DatePickerTests {

	[Fact]
	public void DatePicker_ChangingCultureChangesFormat ()
	{
		var date = new DateTime (2000, 7, 23);
		var datePicker = new DatePicker (date);

		datePicker.Culture = CultureInfo.GetCultureInfo ("en-GB");
		Assert.Equal ("23/07/2000", datePicker.Text);

		datePicker.Culture = CultureInfo.GetCultureInfo ("pl-PL");
		Assert.Equal ("23.07.2000", datePicker.Text);

		// Deafult date format for en-US is M/d/yyyy but we are using StandardizeDateFormat method
		// to convert it to the format that has 2 digits for month and day.
		datePicker.Culture = CultureInfo.GetCultureInfo ("en-US");
		Assert.Equal ("07/23/2000", datePicker.Text);
	}

	[Fact]
	public void DatePicker_Initialize_ShouldSetCurrentDate ()
	{
		var datePicker = new DatePicker ();
		Assert.Equal (DateTime.Now.Date.Day, datePicker.Date.Day);
		Assert.Equal (DateTime.Now.Date.Month, datePicker.Date.Month);
		Assert.Equal (DateTime.Now.Date.Year, datePicker.Date.Year);
	}

	[Fact]
	public void DatePicker_SetDate_ShouldChangeText ()
	{
		var datePicker = new DatePicker () {
			Culture = CultureInfo.GetCultureInfo ("en-GB")
		};
		var newDate = new DateTime (2024, 1, 15);
		var format = CultureInfo.CurrentCulture.DateTimeFormat.ShortDatePattern;

		datePicker.Date = newDate;
		Assert.Equal (newDate.ToString (format), datePicker.Text);
	}

	[Fact]
	[AutoInitShutdown]
	public void DatePicker_ShouldNot_SetDateOutOfRange_UsingPreviousMonthButton ()
	{
		var date = new DateTime (1, 2, 15);
		var datePicker = new DatePicker (date);

		// Move focus to previous month button
		Application.Top.Add (datePicker);
		Application.Begin (Application.Top);

		// set focus to the previous month button
		datePicker.FocusNext ();
		datePicker.FocusNext ();

		// Change month to January 
		Assert.True (datePicker.NewKeyDownEvent (new (KeyCode.Enter)));
		Assert.Equal (1, datePicker.Date.Month);

		// Date should not change as previous month button is disabled
		Assert.False (datePicker.NewKeyDownEvent (new (KeyCode.Enter)));
		Assert.Equal (1, datePicker.Date.Month);
	}

	[Fact]
	[AutoInitShutdown]
	public void DatePicker_ShouldNot_SetDateOutOfRange_UsingNextMonthButton ()
	{
		var date = new DateTime (9999, 11, 15);
		var datePicker = new DatePicker (date);

		Application.Top.Add (datePicker);
		Application.Begin (Application.Top);

		// Set focus to next month button
		datePicker.FocusNext ();
		datePicker.FocusNext ();
		datePicker.FocusNext ();

		// Change month to December
		Assert.True (datePicker.NewKeyDownEvent (new (KeyCode.Enter)));
		Assert.Equal (12, datePicker.Date.Month);

		// Date should not change as next month button is disabled
		Assert.False (datePicker.NewKeyDownEvent (new (KeyCode.Enter)));
		Assert.Equal (12, datePicker.Date.Month);
	}
}