#include "XCEngine/RHI/D3D12/D3D12SwapChain.h"

namespace XCEngine {
namespace RHI {

D3D12SwapChain::D3D12SwapChain()
    : m_windowHandle(nullptr)
    , m_width(0)
    , m_height(0)
    , m_bufferCount(2) {
}

D3D12SwapChain::~D3D12SwapChain() {
    Shutdown();
}

bool D3D12SwapChain::Initialize(IDXGIFactory4* factory, ID3D12CommandQueue* commandQueue, HWND windowHandle, uint32_t width, uint32_t height, uint32_t bufferCount) {
    DXGI_SWAP_CHAIN_DESC swapChainDesc = {};
    swapChainDesc.BufferCount = bufferCount;
    swapChainDesc.BufferDesc.Width = width;
    swapChainDesc.BufferDesc.Height = height;
    swapChainDesc.BufferDesc.Format = DXGI_FORMAT_R8G8B8A8_UNORM;
    swapChainDesc.BufferUsage = DXGI_USAGE_RENDER_TARGET_OUTPUT;
    swapChainDesc.SwapEffect = DXGI_SWAP_EFFECT_FLIP_DISCARD;
    swapChainDesc.OutputWindow = windowHandle;
    swapChainDesc.SampleDesc.Count = 1;
    swapChainDesc.SampleDesc.Quality = 0;
    swapChainDesc.Windowed = TRUE;

    IDXGISwapChain* swapChain = nullptr;
    HRESULT hResult = factory->CreateSwapChain(commandQueue, &swapChainDesc, &swapChain);
    if (FAILED(hResult)) {
        return false;
    }

    hResult = swapChain->QueryInterface(IID_PPV_ARGS(&m_swapChain));
    if (FAILED(hResult)) {
        return false;
    }

    m_commandQueue = commandQueue;
    m_windowHandle = windowHandle;
    m_width = width;
    m_height = height;
    m_bufferCount = bufferCount;

    return true;
}

bool D3D12SwapChain::Initialize(IDXGISwapChain* swapChain, uint32_t width, uint32_t height) {
    HRESULT hResult = swapChain->QueryInterface(IID_PPV_ARGS(&m_swapChain));
    if (FAILED(hResult)) {
        return false;
    }

    m_width = width;
    m_height = height;

    m_backBuffers.resize(m_bufferCount);
    for (uint32_t i = 0; i < m_bufferCount; ++i) {
        ID3D12Resource* resource = nullptr;
        m_swapChain->GetBuffer(i, IID_PPV_ARGS(&resource));
        m_backBuffers[i].InitializeFromExisting(resource);
    }

    return true;
}

void D3D12SwapChain::Shutdown() {
    m_swapChain.Reset();
}

uint32_t D3D12SwapChain::GetCurrentBackBufferIndex() const {
    return m_swapChain->GetCurrentBackBufferIndex();
}

IResource* D3D12SwapChain::GetBackBuffer(uint32_t index) const {
    if (index < m_backBuffers.size()) {
        return const_cast<D3D12Texture*>(&m_backBuffers[index]);
    }
    return nullptr;
}

void D3D12SwapChain::Present(uint32_t syncInterval, uint32_t flags) {
    m_swapChain->Present(syncInterval, flags);
}

void D3D12SwapChain::Resize(uint32_t width, uint32_t height) {
    m_swapChain->ResizeBuffers(m_bufferCount, width, height, DXGI_FORMAT_R8G8B8A8_UNORM, 0);
    m_width = width;
    m_height = height;
}

void D3D12SwapChain::SetFullscreen(bool fullscreen) {
    m_swapChain->SetFullscreenState(fullscreen, nullptr);
}

bool D3D12SwapChain::IsFullscreen() const {
    BOOL fullscreen = FALSE;
    m_swapChain->GetFullscreenState(&fullscreen, nullptr);
    return fullscreen != FALSE;
}

void* D3D12SwapChain::GetNativeHandle() const {
    return reinterpret_cast<void*>(m_swapChain.Get());
}

} // namespace RHI
} // namespace XCEngine