using Blacklight.Core.Cameras;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Azimuth;

namespace Blacklight.Core.UnitTests.Cameras
{
    public class ScreenSpaceCameraTests : UnitTestSharp.TestFixture
    {
        public class Ctor : UnitTestSharp.TestFixture
        {
            public void EmptyCtor()
            {
                var camera = new ScreenSpaceCamera();
                CheckEqual(1, camera.Magnification);
                CheckEqual(Vector.Zero, camera.Position);
                CheckEqual(new AffineMatrix(0, Vector.Zero, 1), camera.CameraToProjection);
                CheckEqual(new AffineMatrix(0, Vector.Zero, 1), camera.ProjectionToCamera);
            }

            public void ViewportCtor()
            {
                var viewport = new Viewport(800, 600);
                var camera = new ScreenSpaceCamera(viewport);
                CheckEqual(1, camera.Magnification);
                CheckEqual(new Vector(400, -300), camera.Position);
            }
        }

        public void ResizeMovesPosition()
        {
            var viewport = new Viewport(800, 600);
            var camera = new ScreenSpaceCamera(viewport);
            viewport.Resize(300, 400);
            CheckEqual(new Vector(150, -200), camera.Position);
        }

        public void MagnificationChangesPosition()
        {
            var viewport = new Viewport(800, 600);
            var camera = new ScreenSpaceCamera(viewport);
            camera.Magnification = 2;
            CheckEqual(new Vector(200, -150), camera.Position);
        }

        public void MagnificationChangesCameraToProjection()
        {
            var camera = new ScreenSpaceCamera();
            camera.Magnification = 2;
            CheckEqual(new AffineMatrix(0, Vector.Zero, 2), camera.CameraToProjection);
            CheckEqual(new AffineMatrix(0, Vector.Zero, 0.5), camera.ProjectionToCamera);
        }
    }
}