using Annulus;
using Azimuth;
using System;
using UnitTestSharp;

namespace Glass.UnitTests
{
    public class BandsMaterialTests : TestFixture
    {
        public static readonly Material Band = new SolidColorMaterial { DebugName = "band" };

        public static Rect RectAt(Scalar x, Scalar y, Scalar width, Scalar height)
        {
            return Rect.FromPositionAndSize(new Vector(x, y), new Vector(width, height));
        }

        public class CtorTests : TestFixture
        {
            public void KeepsTheBandMaterial()
            {
                CheckEqual(Band, new BandsMaterial(Band).BandMaterial);
            }

            public void ReportsTheBandMaterialAsItsOnlyChild()
            {
                var material = new BandsMaterial(Band);

                CheckEqual(1, material.ChildMaterials.Count);
                CheckEqual(Band, material.ChildMaterials[0]);
            }

            public void StartsWithNoBands()
            {
                CheckEqual(0, new BandsMaterial(Band).Count);
            }

            public void NoBandMaterial_Throws()
            {
                CheckThrow(typeof(ArgumentNullException));
                new BandsMaterial(null);
            }
        }

        public class AddTests : TestFixture
        {
            public void KeepsTheBandsInTheOrderAdded()
            {
                var material = new BandsMaterial(Band);

                material.Add(RectAt(1, 2, 3, 4));
                material.Add(RectAt(5, 6, 7, 8));

                CheckEqual(2, material.Count);
                CheckEqual(RectAt(1, 2, 3, 4), material[0]);
                CheckEqual(RectAt(5, 6, 7, 8), material[1]);
            }

            public void MoreThanTheStartingRoomForIsKept()
            {
                var material = new BandsMaterial(Band);

                for (int i = 0; i < 20; ++i)
                {
                    material.Add(RectAt(i, 0, 1, 1));
                }

                CheckEqual(20, material.Count);
                CheckEqual(RectAt(0, 0, 1, 1), material[0]);
                CheckEqual(RectAt(19, 0, 1, 1), material[19]);
            }
        }

        public class ClearTests : TestFixture
        {
            public void TakesAwayEveryBand()
            {
                var material = new BandsMaterial(Band);
                material.Add(RectAt(1, 2, 3, 4));
                material.Add(RectAt(5, 6, 7, 8));

                material.Clear();

                CheckEqual(0, material.Count);
            }

            public void LeavesRoomToAddAgain()
            {
                var material = new BandsMaterial(Band);
                material.Add(RectAt(1, 2, 3, 4));
                material.Clear();

                material.Add(RectAt(5, 6, 7, 8));

                CheckEqual(1, material.Count);
                CheckEqual(RectAt(5, 6, 7, 8), material[0]);
            }
        }

        public class CopyTests : TestFixture
        {
            public void HoldsTheBandsTheOriginalHad()
            {
                var original = new BandsMaterial(Band);
                original.Add(RectAt(1, 2, 3, 4));

                BandsMaterial copy = original with { DebugName = "copy" };

                CheckEqual(1, copy.Count);
                CheckEqual(RectAt(1, 2, 3, 4), copy[0]);
                CheckEqual(Band, copy.BandMaterial);
            }

            public void AddingToTheCopy_LeavesTheOriginalAlone()
            {
                var original = new BandsMaterial(Band);
                BandsMaterial copy = original with { DebugName = "copy" };

                copy.Add(RectAt(1, 2, 3, 4));

                CheckEqual(0, original.Count);
            }

            public void ClearingTheOriginal_LeavesTheCopyAlone()
            {
                var original = new BandsMaterial(Band);
                original.Add(RectAt(1, 2, 3, 4));
                BandsMaterial copy = original with { DebugName = "copy" };

                original.Clear();

                CheckEqual(1, copy.Count);
            }
        }
    }
}