using Ghost.Core;
using Win32;
using Win32.Graphics.Direct3D;
using Win32.Graphics.Direct3D12;
using Win32.Graphics.Dxgi;

namespace Ghost.Graphics.D3D12;

/// <summary>
/// Legacy D3D12 GraphicsDevice - DEPRECATED
/// Use D3D12RenderDevice instead for new code
/// This class remains for compatibility during migration
/// </summary>
[Obsolete("Use D3D12RenderDevice instead")]
internal unsafe class GraphicsDevice
{
    private ComPtr<IDXGIFactory7> _dxgiFactory;
    private ComPtr<ID3D12Device14> _device;
    private ComPtr<IDXGIAdapter1> _adapter;
    private ComPtr<ID3D12CommandQueue> _commandQueue;

    private bool _disposed;

    public ConstPtr<ID3D12Device14> NativeDevice => new(_device.Get());
    public ConstPtr<IDXGIFactory7> DXGIFactory => new(_dxgiFactory.Get());
    public ConstPtr<IDXGIAdapter1> Adapter => new(_adapter.Get());
    public ConstPtr<ID3D12CommandQueue> CommandQueue => new(_commandQueue.Get());

    public GraphicsDevice()
    {
        InitializeDevice();
        InitializeCommandQueue();
    }

    private void InitializeDevice()
    {
#if DEBUG
        CreateDXGIFactory2(true, __uuidof<IDXGIFactory7>(), _dxgiFactory.GetVoidAddressOf());
#else
        CreateDXGIFactory2(false, __uuidof<IDXGIFactory7>(), _dxgiFactory.GetVoidAddressOf());
#endif

        using ComPtr<IDXGIAdapter1> adapter = default;

        for (uint adapterIndex = 0;
            _dxgiFactory.Get()->EnumAdapterByGpuPreference(adapterIndex, GpuPreference.HighPerformance, __uuidof<IDXGIAdapter1>(), adapter.ReleaseAndGetVoidAddressOf()).Success;
            adapterIndex++)
        {
            AdapterDescription1 desc = default;
            adapter.Get()->GetDesc1(&desc);

            // Don't select the Basic Render Driver adapter.
            if ((desc.Flags & AdapterFlags.Software) != AdapterFlags.None)
            {
                continue;
            }

            if (D3D12CreateDevice((IUnknown*)adapter.Get(), FeatureLevel.Level_12_0, __uuidof<ID3D12Device14>(), _device.GetVoidAddressOf()).Success)
            {
                _adapter = adapter.Move();
                break;
            }
        }

        if (_device.Get() == null)
        {
            throw new PlatformNotSupportedException("Cannot create ID3D12Device with feature level 12.0");
        }
    }

    private void InitializeCommandQueue()
    {
        var queueDesc = new CommandQueueDescription
        {
            Type = CommandListType.Direct,
            Priority = (int)CommandQueuePriority.High,
            Flags = CommandQueueFlags.None,
        };

        fixed (void* queuePtr = &_commandQueue)
        {
            _device.Get()->CreateCommandQueue(&queueDesc, __uuidof<ID3D12CommandQueue>(), (void**)queuePtr);
        }
    }

    public void Dispose()
    {
        if (_disposed)
        {
            return;
        }

        _commandQueue.Dispose();
        _device.Reset();
        _dxgiFactory.Dispose();

        _disposed = true;
    }
}