PixiEditor/PixiEditorTests/ModelsTests/ControllersTests/PixelChangesControllerTests.cs

using PixiEditor.Models.Controllers;
using PixiEditor.Models.DataHolders;
using PixiEditor.Models.Position;
using SkiaSharp;
using System;
using Xunit;

namespace PixiEditorTests.ModelsTests.ControllersTests
{
    public class PixelChangesControllerTests
    {
        [Fact]
        public void TestThatPopChangesPopsChanges()
        {
            PixelChangesController controller = CreateBasicController().Item2;

            System.Tuple<LayerChange, LayerChange>[] changes = controller.PopChanges();
            Assert.NotEmpty(changes);
            Assert.Null(controller.PopChanges());
        }

        [Fact]
        public void TestThatAddChangesAddsAsNewChange()
        {
            var data = CreateBasicController();
            PixelChangesController controller = data.Item2;
            Coordinates[] cords = { new Coordinates(5, 3), new Coordinates(7, 2) };
            Guid guid = Guid.NewGuid();

            controller.AddChanges(
                new LayerChange(
                    BitmapPixelChanges.FromSingleColoredArray(cords, SKColors.Black), guid),
                new LayerChange(BitmapPixelChanges.FromSingleColoredArray(cords, SKColors.Transparent), guid));

            System.Tuple<LayerChange, LayerChange>[] changes = controller.PopChanges();
            Assert.Equal(2, changes.Length);
        }

        [Fact]
        public void TestThatAddChangesAddsToExistingChange()
        {
            Coordinates[] cords2 = { new Coordinates(2, 2), new Coordinates(5, 5) };
            var data = CreateBasicController();
            PixelChangesController controller = data.Item2;

            controller.AddChanges(
                new LayerChange(
                    BitmapPixelChanges.FromSingleColoredArray(cords2, SKColors.Black), data.Item1),
                new LayerChange(BitmapPixelChanges.FromSingleColoredArray(cords2, SKColors.Transparent), data.Item1));

            Tuple<LayerChange, LayerChange>[] changes = controller.PopChanges();
            Assert.Single(changes);
            Assert.Equal(4, changes[0].Item1.PixelChanges.ChangedPixels.Count);
            Assert.Equal(4, changes[0].Item2.PixelChanges.ChangedPixels.Count);
        }

        private static Tuple<Guid, PixelChangesController> CreateBasicController()
        {
            Coordinates[] cords = { new Coordinates(0, 0), new Coordinates(1, 1) };
            PixelChangesController controller = new PixelChangesController();

            Guid guid = Guid.NewGuid();

            controller.AddChanges(
                new LayerChange(
                    BitmapPixelChanges.FromSingleColoredArray(cords, SKColors.Black), guid),
                new LayerChange(BitmapPixelChanges.FromSingleColoredArray(cords, SKColors.Transparent), guid));
            return new Tuple<Guid, PixelChangesController>(guid, controller);
        }
    }
}