using System;
using System.Globalization;
using System.Threading;
using Xunit;
using Xunit.Abstractions;

// Alias Console to MockConsole so we don't accidentally use Console
using Console = Terminal.Gui.FakeConsole;

namespace Terminal.Gui.ViewTests;

public class DimAutoTests {
	readonly ITestOutputHelper _output;

	public DimAutoTests (ITestOutputHelper output)
	{
		_output = output;
		Console.OutputEncoding = System.Text.Encoding.Default;
		// Change current culture
		var culture = CultureInfo.CreateSpecificCulture ("en-US");
		Thread.CurrentThread.CurrentCulture = culture;
		Thread.CurrentThread.CurrentUICulture = culture;
	}

	[Fact]
	public void NoSubViews_Does_Nothing ()
	{
		var superView = new View () {
			X = 0,
			Y = 0,
			Width = Dim.Auto (),
			Height = Dim.Auto (),
			ValidatePosDim = true,
		};

		superView.BeginInit ();
		superView.EndInit ();
		superView.SetRelativeLayout (new Rect (0, 0, 0, 0));
		Assert.Equal (new Rect (0, 0, 0, 0), superView.Frame);

		superView.SetRelativeLayout (new Rect (0, 0, 10, 10));
		Assert.Equal (new Rect (0, 0, 0, 0), superView.Frame);

		superView.SetRelativeLayout (new Rect (10, 10, 10, 10));
		Assert.Equal (new Rect (0, 0, 0, 0), superView.Frame);
	}
	
	[Theory]
	[InlineData (0, 0, 0, 0, 0, 0)]
	[InlineData (0, 0, 5, 0, 5, 0)]
	[InlineData (0, 0, 0, 5, 0, 5)]
	[InlineData (0, 0, 5, 5, 5, 5)]

	[InlineData (1, 0, 5, 0, 6, 0)]
	[InlineData (1, 0, 0, 5, 1, 5)]
	[InlineData (1, 0, 5, 5, 6, 5)]
	[InlineData (1, 1, 5, 5, 6, 6)]

	[InlineData (-1, 0, 5, 0, 4, 0)]
	[InlineData (-1, 0, 0, 5, 0, 5)]
	[InlineData (-1, 0, 5, 5, 4, 5)]
	[InlineData (-1, -1, 5, 5, 4, 4)]
	public void SubView_ChangesSuperViewSize (int subX, int subY, int subWidth, int subHeight, int expectedWidth, int expectedHeight)
	{
		var superView = new View () {
			X = 0,
			Y = 0,
			Width = Dim.Auto (),
			Height = Dim.Auto (),
			ValidatePosDim = true,
		};

		var subView = new View () {
			X = subX,
			Y = subY,
			Width = subWidth,
			Height = subHeight,
			ValidatePosDim = true,
		};

		superView.Add (subView);

		superView.BeginInit ();
		superView.EndInit ();
		superView.SetRelativeLayout (new Rect (0, 0, 0, 0));
		Assert.Equal (new Rect (0, 0, expectedWidth, expectedHeight), superView.Frame);
	}

	[Theory]
	[InlineData (0, 0, 0, 0, 0)]
	[InlineData (0, 0, 5, 0, 5)]
	[InlineData (0, 0, 0, 5, 0)]
	[InlineData (0, 0, 5, 5, 5)]

	[InlineData (1, 0, 5, 0, 6)]
	[InlineData (1, 0, 0, 5, 1)]
	[InlineData (1, 0, 5, 5, 6)]
	[InlineData (1, 1, 5, 5, 6)]

	[InlineData (-1, 0, 5, 0, 4)]
	[InlineData (-1, 0, 0, 5, 0)]
	[InlineData (-1, 0, 5, 5, 4)]
	[InlineData (-1, -1, 5, 5, 4)]
	public void Width_Auto_Height_NotChanged (int subX, int subY, int subWidth, int subHeight, int expectedWidth)
	{
		var superView = new View () {
			X = 0,
			Y = 0,
			Width = Dim.Auto (),
			Height = 10,
			ValidatePosDim = true,
		};

		var subView = new View () {
			X = subX,
			Y = subY,
			Width = subWidth,
			Height = subHeight,
			ValidatePosDim = true,
		};

		superView.Add (subView);

		superView.BeginInit ();
		superView.EndInit ();
		superView.SetRelativeLayout (new Rect (0, 0, 0, 0));
		Assert.Equal (new Rect (0, 0, expectedWidth, 10), superView.Frame);
	}

	[Theory]
	[InlineData (0, 0, 0, 0, 0)]
	[InlineData (0, 0, 5, 0, 0)]
	[InlineData (0, 0, 0, 5, 5)]
	[InlineData (0, 0, 5, 5, 5)]

	[InlineData (1, 0, 5, 0, 0)]
	[InlineData (1, 0, 0, 5, 5)]
	[InlineData (1, 0, 5, 5, 5)]
	[InlineData (1, 1, 5, 5, 6)]

	[InlineData (-1, 0, 5, 0, 0)]
	[InlineData (-1, 0, 0, 5, 5)]
	[InlineData (-1, 0, 5, 5, 5)]
	[InlineData (-1, -1, 5, 5, 4)]
	public void Height_Auto_Width_NotChanged (int subX, int subY, int subWidth, int subHeight, int expectedHeight)
	{
		var superView = new View () {
			X = 0,
			Y = 0,
			Width = 10,
			Height = Dim.Auto (),
			ValidatePosDim = true,
		};

		var subView = new View () {
			X = subX,
			Y = subY,
			Width = subWidth,
			Height = subHeight,
			ValidatePosDim = true,
		};

		superView.Add (subView);

		superView.BeginInit ();
		superView.EndInit ();
		superView.SetRelativeLayout (new Rect (0, 0, 0, 0));
		Assert.Equal (new Rect (0, 0, 10, expectedHeight), superView.Frame);
	}

	// Test validation
	[Fact]
	public void ValidatePosDim_True_Throws_When_SubView_Uses_SuperView_Dims ()
	{
		var superView = new View () {
			X = 0,
			Y = 0,
			Width = Dim.Auto (),
			Height = Dim.Auto (),
			ValidatePosDim = true,
		};

		var subView = new View () {
			X = 0,
			Y = 0,
			Width = Dim.Fill (),
			Height = 10
		};

		superView.BeginInit ();
		superView.EndInit ();

		Assert.Throws<InvalidOperationException> (() => superView.Add (subView));

		subView.Width = 10;
		superView.Add (subView);
		superView.BeginInit ();
		superView.EndInit ();
		superView.SetRelativeLayout (new Rect (0, 0, 0, 0));
		superView.LayoutSubviews (); // no throw

		Assert.Throws<InvalidOperationException> (() => subView.Width = Dim.Fill ());
		subView.Width = 10;

		Assert.Throws<InvalidOperationException> (() => subView.Height = Dim.Fill ());
		subView.Height = 10;

		Assert.Throws<InvalidOperationException> (() => subView.Height = Dim.Percent (50));
		subView.Height = 10;
		
		Assert.Throws<InvalidOperationException> (() => subView.X = Pos.Center ());
		subView.X = 0;
		
		Assert.Throws<InvalidOperationException> (() => subView.Y = Pos.Center ());
		subView.Y = 0;

		subView.Width = 10;
		subView.Height = 10;
		subView.X = 0;
		subView.Y = 0;
		superView.SetRelativeLayout (new Rect (0, 0, 0, 0));
		superView.LayoutSubviews ();
	}

	// Test validation
	[Fact]
	public void ValidatePosDim_True_Throws_When_SubView_Uses_SuperView_Dims_Combine ()
	{
		var superView = new View () {
			X = 0,
			Y = 0,
			Width = Dim.Auto (),
			Height = Dim.Auto (),
			ValidatePosDim = true,
		};

		var subView = new View () {
			X = 0,
			Y = 0,
			Width = 10,
			Height = 10
		};


		var subView2 = new View () {
			X = 0,
			Y = 0,
			Width = 10,
			Height = 10
		};

		superView.Add (subView, subView2);
		superView.BeginInit ();
		superView.EndInit ();
		superView.SetRelativeLayout (new Rect (0, 0, 0, 0));
		superView.LayoutSubviews (); // no throw

		Assert.Throws<InvalidOperationException> (() => subView.Height = Dim.Fill () + 3);
		subView.Height = 0;

		Assert.Throws<InvalidOperationException> (() => subView.Height = 3 + Dim.Fill ());
		subView.Height = 0;

		Assert.Throws<InvalidOperationException> (() => subView.Height = 3 + 5 + Dim.Fill ());
		subView.Height = 0;

		
		Assert.Throws<InvalidOperationException> (() => subView.Height = 3 + 5 + Dim.Percent (10));
		subView.Height = 0;

		// Tests nested Combine
		Assert.Throws<InvalidOperationException> (() => subView.Height = 5 + new Dim.DimCombine (true, 3, new Dim.DimCombine (true, Dim.Percent (10), 9)));
	}

	[Fact]
	public void ValidatePosDim_True_Throws_When_SubView_Uses_SuperView_Pos_Combine ()
	{
		var superView = new View () {
			X = 0,
			Y = 0,
			Width = Dim.Auto (),
			Height = Dim.Auto (),
			ValidatePosDim = true,
		};

		var subView = new View () {
			X = 0,
			Y = 0,
			Width = 10,
			Height = 10
		};

		var subView2 = new View () {
			X = 0,
			Y = 0,
			Width = 10,
			Height = 10
		};

		superView.Add (subView, subView2);
		superView.BeginInit ();
		superView.EndInit ();
		superView.SetRelativeLayout (new Rect (0, 0, 0, 0));
		superView.LayoutSubviews (); // no throw

		subView.X = Pos.Right (subView2);
		superView.SetRelativeLayout (new Rect (0, 0, 0, 0));
		superView.LayoutSubviews (); // no throw

		subView.X = Pos.Right (subView2) + 3;
		superView.SetRelativeLayout (new Rect (0, 0, 0, 0)); // no throw
		superView.LayoutSubviews (); // no throw

		subView.X = new Pos.PosCombine (true, Pos.Right (subView2), new Pos.PosCombine (true, 7, 9));
		superView.SetRelativeLayout (new Rect (0, 0, 0, 0)); // no throw

		Assert.Throws<InvalidOperationException> (() => subView.X = Pos.Center () + 3);
		subView.X = 0;
		
		Assert.Throws<InvalidOperationException> (() => subView.X = 3 + Pos.Center ());
		subView.X = 0;

		Assert.Throws<InvalidOperationException> (() => subView.X = 3 + 5 + Pos.Center ());
		subView.X = 0;

		Assert.Throws<InvalidOperationException> (() => subView.X = 3 + 5 + Pos.Percent (10));
		subView.X = 0;

		Assert.Throws<InvalidOperationException> (() => subView.X = Pos.Percent (10) + Pos.Center ());
		subView.X = 0;

		// Tests nested Combine
		Assert.Throws<InvalidOperationException> (() => subView.X = 5 + new Pos.PosCombine (true, Pos.Right (subView2), new Pos.PosCombine (true, Pos.Center (), 9)));
		subView.X = 0;
	}

	// Test min - ensure that if min is specified in the DimAuto constructor it is honored
	[Fact]
	public void DimAuto_Min ()
	{
		var superView = new View () {
			X = 0,
			Y = 0,
			Width = Dim.Auto (min: 10),
			Height = Dim.Auto (min: 10),
			ValidatePosDim = true,
		};

		var subView = new View () {
			X = 0,
			Y = 0,
			Width = 5,
			Height = 5
		};

		superView.Add (subView);
		superView.BeginInit ();
		superView.EndInit ();

		superView.SetRelativeLayout (new Rect (0, 0, 0, 0));
		superView.LayoutSubviews (); // no throw

		Assert.Equal (10, superView.Frame.Width);
		Assert.Equal (10, superView.Frame.Height);
	}

	[Fact]
	public void DimAuto_Min_Resets_If_Subview_Shrinks ()
	{
		var superView = new View () {
			X = 0,
			Y = 0,
			Width = Dim.Auto (min: 10),
			Height = Dim.Auto (min: 10),
			ValidatePosDim = true,
		};

		var subView = new View () {
			X = 0,
			Y = 0,
			Width = 5,
			Height = 5
		};

		superView.Add (subView);
		superView.BeginInit ();
		superView.EndInit ();

		superView.SetRelativeLayout (new Rect (0, 0, 0, 0));
		superView.LayoutSubviews (); // no throw

		Assert.Equal (10, superView.Frame.Width);
		Assert.Equal (10, superView.Frame.Height);

		subView.Width = 3;
		subView.Height = 3;
		superView.SetRelativeLayout (new Rect (0, 0, 0, 0));
		superView.LayoutSubviews (); // no throw

		Assert.Equal (3, subView.Frame.Width);
		Assert.Equal (3, subView.Frame.Height);

		Assert.Equal (10, superView.Frame.Width);
		Assert.Equal (10, superView.Frame.Height);
	}

	// what happens if DimAuto (min: 10) and the subview moves to a negative coord?
	[Fact]
	public void DimAuto_Min_Resets_If_Subview_Moves_Negative ()
	{
		var superView = new View () {
			X = 0,
			Y = 0,
			Width = Dim.Auto (min: 10),
			Height = Dim.Auto (min: 10),
			ValidatePosDim = true,
		};

		var subView = new View () {
			X = 0,
			Y = 0,
			Width = 5,
			Height = 5
		};

		superView.Add (subView);
		superView.BeginInit ();
		superView.EndInit ();

		superView.SetRelativeLayout (new Rect (0, 0, 0, 0));
		superView.LayoutSubviews (); // no throw

		Assert.Equal (10, superView.Frame.Width);
		Assert.Equal (10, superView.Frame.Height);

		subView.X = -1;
		subView.Y = -1;
		superView.SetRelativeLayout (new Rect (0, 0, 0, 0));
		superView.LayoutSubviews (); // no throw

		Assert.Equal (5, subView.Frame.Width);
		Assert.Equal (5, subView.Frame.Height);

		Assert.Equal (10, superView.Frame.Width);
		Assert.Equal (10, superView.Frame.Height);
	}

	// Test variations of Frame

}