PixiEditor/PixiEditorTests/ModelsTests/LayersTests/LayerTests.cs

using PixiEditor.Models.DataHolders;
using PixiEditor.Models.Layers;
using PixiEditor.Models.Position;
using SkiaSharp;
using Xunit;

namespace PixiEditorTests.ModelsTests.LayersTests
{
    public class LayerTests
    {
        [Fact]
        public void TestThatEmptyLayerGeneratesCorrectly()
        {
            Layer layer = new Layer("layer");

            Assert.Equal("layer", layer.Name);
            Assert.Equal(1, layer.Width);
            Assert.Equal(1, layer.Height);
            Assert.Equal(1, layer.LayerBitmap.Width);
            Assert.Equal(1, layer.LayerBitmap.Height);
        }

        [Fact]
        public void TestThatEmptyLayerWithSizeGeneratesCorrectly()
        {
            Layer layer = new Layer("layer", 10, 10);

            Assert.Equal("layer", layer.Name);
            Assert.Equal(10, layer.Width);
            Assert.Equal(10, layer.Height);
            Assert.Equal(10, layer.LayerBitmap.Width);
            Assert.Equal(10, layer.LayerBitmap.Height);
        }

        [Fact]
        public void TestThatLayerFromBitmapGeneratesCorrectly()
        {
            using Surface bmp = new Surface(10, 10);

            Layer layer = new Layer("layer", bmp);

            Assert.Equal("layer", layer.Name);
            Assert.Equal(10, layer.Width);
            Assert.Equal(10, layer.Height);
            Assert.Equal(10, layer.LayerBitmap.Width);
            Assert.Equal(10, layer.LayerBitmap.Height);
        }

        [Fact]
        public void TestThatCloneClonesCorrectly()
        {
            Layer layer = new Layer("test", 5, 2);

            Layer clone = layer.Clone();

            LayersTestHelper.LayersAreEqual(layer, clone);
        }

        [Fact]
        public void TestThatCloneIsMakingDeepCopyOfBitmap()
        {
            Layer layer = new Layer("test", 5, 2);

            Layer clone = layer.Clone();

            clone.LayerBitmap.SetSRGBPixel(0, 0, SKColors.Lime); // Actually we are checking if modifying clone bitmap does not affect original

            Assert.NotEqual(SKColors.Lime, layer.GetPixel(0, 0));
        }

        [Fact]
        public void TestThatResizeResizesBitmap()
        {
            Layer layer = new Layer("layer", 1, 1);

            layer.SetPixel(new Coordinates(0, 0), SKColors.Black);

            layer.Resize(2, 2, 2, 2);

            Assert.Equal(2, layer.Width);
            Assert.Equal(2, layer.Height);
            Assert.Equal(2, layer.MaxWidth);
            Assert.Equal(2, layer.MaxHeight);

            // 4 is new area of bitmap
            for (int y = 0; y < layer.Height; y++)
            {
                for (int x = 0; x < layer.Width; x++)
                {
                    Assert.Equal(SKColors.Black, layer.GetPixel(x, y));
                }
            }
        }

        [Fact]
        public void TestThatGetPixelReturnsTransparentIfOutOfBounds()
        {
            Layer layer = new Layer("layer");

            Assert.Equal(0, layer.GetPixel(-1, 999).Alpha);
        }

        [Fact]
        public void TestThatSetPixelsSetsPixels() // This also tests if Dynamic Resize works
        {
            Coordinates[] pixels = { new Coordinates(4, 2), new Coordinates(0, 0), new Coordinates(15, 2) };

            Layer layer = new Layer("layer");

            layer.SetPixels(BitmapPixelChanges.FromSingleColoredArray(pixels, SKColors.Lime));

            for (int i = 0; i < pixels.Length; i++)
            {
                Assert.Equal(SKColors.Lime, layer.GetPixelWithOffset(pixels[i].X, pixels[i].Y));
            }
        }

        [Fact]
        public void TestThatClipCanvasResizesBitmapCorrectly()
        {
            Layer layer = new Layer("layer", 10, 10);
            layer.SetPixel(new Coordinates(4, 4), SKColors.Blue);

            layer.ClipCanvas();

            Assert.Equal(1, layer.Width);
            Assert.Equal(1, layer.Height);
            Assert.Equal(SKColors.Blue, layer.GetPixel(0, 0));
        }
    }
}