using System;
using System.Windows.Forms;
using SharpDX.Direct3D9;
using UnitTestSharp;

namespace Blacklight.SharpDX9.UnitTesting
{
    // Creating a real device burns past the 500ms setup budget, so each test builds its window in its own
    // [CpuTimeout]-widened body and the fixture only tears it down.
    public class SharpDX9BatchFactoryTests : TestFixture
    {
        public static bool QuadIsOnItsOwnDevice(SharpDX9BatchFactory factory)
        {
            IntPtr expected = factory.GraphicsDevice.NativePointer;

            using (Device cornerOwner = factory.CornerQuadBuffer.Device)
            using (Device indexOwner = factory.QuadIndexBuffer.Device)
            using (Device declarationOwner = factory.PrimitiveDeclaration.Device)
            {
                return cornerOwner.NativePointer == expected && indexOwner.NativePointer == expected &&
                    declarationOwner.NativePointer == expected;
            }
        }

        public class CtorTests : TestFixture
        {
            private Module module;
            private Form firstWindow;
            private Form secondWindow;
            private SharpDX9WindowHandle first;
            private SharpDX9WindowHandle second;

            public override void FixtureTeardown()
            {
                first?.Dispose();
                second?.Dispose();
                firstWindow?.Dispose();
                secondWindow?.Dispose();
                module?.Dispose();
            }

            [CpuTimeout(10000)]
            public void EachDevice_GetsItsOwnQuad()
            {
                module = new Module();
                firstWindow = new Form();
                secondWindow = new Form();
                first = (SharpDX9WindowHandle)module.CreateDrawableSurfaceOnWindow(firstWindow.Handle);
                second = (SharpDX9WindowHandle)module.CreateDrawableSurfaceOnWindow(secondWindow.Handle);

                CheckTrue(QuadIsOnItsOwnDevice(first.Backend));
                CheckTrue(QuadIsOnItsOwnDevice(second.Backend));
            }
        }

        public class ReleaseResourcesTests : TestFixture
        {
            private Module module;
            private Form window;
            private SharpDX9WindowHandle handle;

            public override void FixtureTeardown()
            {
                handle?.Dispose();
                window?.Dispose();
                module?.Dispose();
            }

            [CpuTimeout(5000)]
            public void DropsTheQuad()
            {
                module = new Module();
                window = new Form();
                handle = (SharpDX9WindowHandle)module.CreateDrawableSurfaceOnWindow(window.Handle);

                handle.Backend.ReleaseResources();

                CheckNull(handle.Backend.CornerQuadBuffer);
                CheckNull(handle.Backend.QuadIndexBuffer);
                CheckNull(handle.Backend.PrimitiveDeclaration);
            }
        }

        public class ResetTests : TestFixture
        {
            private Module module;
            private Form window;
            private SharpDX9WindowHandle handle;

            public override void FixtureTeardown()
            {
                handle?.Dispose();
                window?.Dispose();
                module?.Dispose();
            }

            [CpuTimeout(5000)]
            public void AfterARelease_RebuildsTheQuadOnTheSameDevice()
            {
                module = new Module();
                window = new Form();
                handle = (SharpDX9WindowHandle)module.CreateDrawableSurfaceOnWindow(window.Handle);
                handle.Backend.ReleaseResources();

                handle.Backend.Reset();

                CheckTrue(QuadIsOnItsOwnDevice(handle.Backend));
            }
        }
    }
}