using UnitTestSharp;
using Azimuth;
using Annulus;

namespace Glass.UnitTests
{
    public class SpotlightMaterialTests : TestFixture
    {
        public static readonly Rect Screen = Rect.FromTwoPoints(Vector.Zero, new Vector(800, 600));

        public static readonly Rect Hole = Rect.FromTwoPoints(new Vector(100, 100), new Vector(300, 250));

        public static SpotlightMaterial Spotlight => new SpotlightMaterial
        {
            DimMaterial = new SolidColorMaterial { DebugName = "dim" },
        };

        public class CtorTests : TestFixture
        {
            public void StartsWithARoomForTheDimAndNothingInIt()
            {
                CheckEqual(1, new SpotlightMaterial().ChildMaterials.Count);
                CheckNull(new SpotlightMaterial().DimMaterial);
            }
        }

        public class DimMaterialTests : TestFixture
        {
            public void Set_IsReadBack()
            {
                var dim = new SolidColorMaterial();

                CheckEqual(dim, new SpotlightMaterial { DimMaterial = dim }.DimMaterial);
            }

            public void Set_IsWhatChildMaterialsReports()
            {
                var dim = new SolidColorMaterial();

                CheckEqual(dim, new SpotlightMaterial { DimMaterial = dim }.ChildMaterials[0]);
            }
        }

        public class ArrangeTests : TestFixture
        {
            public void SplitsTheScreenIntoFourBandsAroundTheHole()
            {
                SpotlightMaterial.Rects rects = Spotlight.Arrange(Hole, Screen);

                CheckEqual(Rect.FromTwoPoints(new Vector(0, 0), new Vector(800, 100)), rects.Top);
                CheckEqual(Rect.FromTwoPoints(new Vector(0, 250), new Vector(800, 600)), rects.Bottom);
                CheckEqual(Rect.FromTwoPoints(new Vector(0, 100), new Vector(100, 250)), rects.Left);
                CheckEqual(Rect.FromTwoPoints(new Vector(300, 100), new Vector(800, 250)), rects.Right);
            }

            public void HoleAgainstAScreenCorner_FlattensTheBandsBesideItRatherThanInvertingThem()
            {
                Rect corner = Rect.FromTwoPoints(Vector.Zero, new Vector(300, 250));

                SpotlightMaterial.Rects rects = Spotlight.Arrange(corner, Screen);

                CheckEqual(0, rects.Top.Height);
                CheckEqual(0, rects.Left.Width);
                CheckEqual(Rect.FromTwoPoints(new Vector(0, 250), new Vector(800, 600)), rects.Bottom);
                CheckEqual(Rect.FromTwoPoints(new Vector(300, 0), new Vector(800, 250)), rects.Right);
            }

            public void HoleOffScreen_LeavesOneBandCoveringTheWholeScreen()
            {
                Rect away = Rect.FromTwoPoints(new Vector(900, 700), new Vector(1000, 800));

                SpotlightMaterial.Rects rects = Spotlight.Arrange(away, Screen);

                CheckEqual(Screen, rects.Bottom);
                CheckEqual(0, rects.Top.Height);
                CheckEqual(0, rects.Left.Width);
                CheckEqual(0, rects.Right.Height);
            }

            public void HoleStraddlingAnEdge_BandsStopAtTheScreenRatherThanFollowingItOut()
            {
                Rect straddling = Rect.FromTwoPoints(new Vector(-50, 100), new Vector(300, 250));

                SpotlightMaterial.Rects rects = Spotlight.Arrange(straddling, Screen);

                CheckEqual(0, rects.Left.Width);
                CheckEqual(new Scalar(0), rects.Top.Left);
                CheckEqual(Rect.FromTwoPoints(new Vector(300, 100), new Vector(800, 250)), rects.Right);
            }

            public void ScreenAwayFromTheOrigin_BandsFollowIt()
            {
                Rect offsetScreen = Rect.FromTwoPoints(new Vector(1000, 500), new Vector(1800, 1100));
                Rect hole = Rect.FromTwoPoints(new Vector(1100, 600), new Vector(1300, 750));

                SpotlightMaterial.Rects rects = Spotlight.Arrange(hole, offsetScreen);

                CheckEqual(Rect.FromTwoPoints(new Vector(1000, 500), new Vector(1800, 600)), rects.Top);
                CheckEqual(Rect.FromTwoPoints(new Vector(1000, 750), new Vector(1800, 1100)), rects.Bottom);
                CheckEqual(Rect.FromTwoPoints(new Vector(1000, 600), new Vector(1100, 750)), rects.Left);
                CheckEqual(Rect.FromTwoPoints(new Vector(1300, 600), new Vector(1800, 750)), rects.Right);
            }
        }
    }
}