using Xunit.Abstractions;
using static Terminal.Gui.Pos;

namespace Terminal.Gui.LayoutTests;

public class PosAnchorEndTests ()
{
    [Fact]
    public void PosAnchorEnd_Constructor ()
    {
        var posAnchorEnd = new PosAnchorEnd (10);
        Assert.NotNull (posAnchorEnd);
    }

    [Theory]
    [InlineData (0, 0, true)]
    [InlineData (10, 10, true)]
    [InlineData (0, 10, false)]
    [InlineData (10, 1, false)]
    public void PosAnchorEnd_Equals (int offset1, int offset2, bool expectedEquals)
    {
        var posAnchorEnd1 = new PosAnchorEnd (offset1);
        var posAnchorEnd2 = new PosAnchorEnd (offset2);

        Assert.Equal (expectedEquals, posAnchorEnd1.Equals (posAnchorEnd2));
        Assert.Equal (expectedEquals, posAnchorEnd2.Equals (posAnchorEnd1));
    }

    [Fact]
    public void PosAnchorEnd_ToString ()
    {
        var posAnchorEnd = new PosAnchorEnd (10);
        var expectedString = "AnchorEnd(10)";

        Assert.Equal (expectedString, posAnchorEnd.ToString ());
    }

    [Fact]
    public void PosAnchorEnd_GetAnchor ()
    {
        var posAnchorEnd = new PosAnchorEnd (10);
        var width = 50;
        var expectedAnchor = width - 10;

        Assert.Equal (expectedAnchor, posAnchorEnd.GetAnchor (width));
    }

    [Fact]
    public void PosAnchorEnd_CreatesCorrectInstance ()
    {
        var pos = Pos.AnchorEnd (10);
        Assert.IsType<PosAnchorEnd> (pos);
    }

    [Fact]
    public void PosAnchorEnd_Negative_Throws ()
    {
        Pos pos;
        int n = -1;
        Assert.Throws<ArgumentOutOfRangeException> (() => pos = Pos.AnchorEnd (n));
    }

    [Theory]
    [InlineData (0)]
    [InlineData (1)]
    public void PosAnchorEnd_SetsValue_GetAnchor_Is_Negative (int offset)
    {
        Pos pos = Pos.AnchorEnd (offset);
        Assert.Equal (offset, -pos.GetAnchor (0));
    }

    [Theory]
    [InlineData (0, 0, 25)]
    [InlineData (0, 10, 25)]
    [InlineData (1, 10, 24)]
    [InlineData (10, 10, 15)]
    [InlineData (20, 10, 5)]
    [InlineData (25, 10, 0)]
    [InlineData (26, 10, -1)]
    public void PosAnchorEnd_With_Offset_PositionsViewOffsetFromRight (int offset, int width, int expectedXPosition)
    {
        // Arrange
        var superView = new View { Width = 25, Height = 25 };
        var view = new View
        {
            X = Pos.AnchorEnd (offset),
            Width = width,
            Height = 1
        };
        superView.Add (view);
        superView.BeginInit ();
        superView.EndInit ();

        // Act
        superView.LayoutSubViews ();

        // Assert
        Assert.Equal (expectedXPosition, view.Frame.X);
    }

    // UseDimForOffset tests

    [Fact]
    public void PosAnchorEnd_UseDimForOffset_CreatesCorrectInstance ()
    {
        var pos = Pos.AnchorEnd ();
        Assert.IsType<PosAnchorEnd> (pos);
        Assert.True (((PosAnchorEnd)pos).UseDimForOffset);
    }

    [Fact]
    public void PosAnchorEnd_UseDimForOffset_SetsValue_GetAnchor_Is_Negative ()
    {
        Pos pos = Pos.AnchorEnd ();
        Assert.Equal (-10, -pos.GetAnchor (10));
    }

    [Theory]
    [InlineData (0, 25)]
    [InlineData (10, 15)]
    [InlineData (9, 16)]
    [InlineData (11, 14)]
    [InlineData (25, 0)]
    [InlineData (26, -1)]
    public void PosAnchorEnd_UseDimForOffset_PositionsViewOffsetByDim (int dim, int expectedXPosition)
    {
        // Arrange
        var superView = new View { Width = 25, Height = 25 };
        var view = new View
        {
            X = Pos.AnchorEnd (),
            Width = dim,
            Height = 1
        };
        superView.Add (view);
        superView.BeginInit ();
        superView.EndInit ();

        // Act
        superView.LayoutSubViews ();

        // Assert
        Assert.Equal (expectedXPosition, view.Frame.X);
    }

    [Theory]
    [InlineData (0, 25)]
    [InlineData (10, 23)]
    [InlineData (50, 13)]
    [InlineData (100, 0)]
    public void PosAnchorEnd_UseDimForOffset_DimPercent_PositionsViewOffsetByDim (int percent, int expectedXPosition)
    {
        // Arrange
        var superView = new View { Width = 25, Height = 25 };
        var view = new View
        {
            X = Pos.AnchorEnd (),
            Width = Dim.Percent (percent),
            Height = 1
        };
        superView.Add (view);
        superView.BeginInit ();
        superView.EndInit ();

        // Act
        superView.LayoutSubViews ();

        // Assert
        Assert.Equal (expectedXPosition, view.Frame.X);
    }

    [Fact]
    public void PosAnchorEnd_Calculate_ReturnsExpectedValue ()
    {
        var posAnchorEnd = new PosAnchorEnd (5);
        var result = posAnchorEnd.Calculate (10, new DimAbsolute (2), null, Dimension.None);
        Assert.Equal (5, result);
    }

    [Fact]
    public void PosAnchorEnd_MinusOne_Combine_Works ()
    {
        var pos = AnchorEnd () - 1;
        var result = pos.Calculate (10, new DimAbsolute (2), null, Dimension.None);
        Assert.Equal (7, result);

    }
}