#include <basalt_export.hpp>
#include <engine.hpp>
#include <windows.h>
#include <d3d11.h>
#include <d3dcompiler.h>
#include <wrl/client.h>
#include <vector>
#include <iostream>

using Microsoft::WRL::ComPtr;

// 常量
constexpr UINT Width = 800;
constexpr UINT Height = 600;
constexpr const wchar_t* PipeName = L"\\\\.\\pipe\\54da494c-301a-47a9-9d67-4fbebaeda8cf";

// 立方体顶点（位置）
struct Vertex {
    float x, y, z;
};
Vertex CubeVertices[] = {
    // 前面
    {-1, -1, -1},
    {1, -1, -1},
    {1, 1, -1},
    {-1, -1, -1},
    {1, 1, -1},
    {-1, 1, -1},
    // 后面
    {-1, -1, 1},
    {-1, 1, 1},
    {1, 1, 1},
    {-1, -1, 1},
    {1, 1, 1},
    {1, -1, 1},
    // 其他面...（为简化，此处略，或用完整立方体）
    // 实际建议使用完整12个三角面（36顶点）
};
// 为简化，这里只渲染前面，实际请补全

// 简单顶点着色器（只传位置）
const char* g_VS = R"(
    float4 main(float3 pos : POSITION) : SV_POSITION {
        return float4(pos, 1.0f);
    }
)";

// 简单像素着色器（返回固定颜色）
const char* g_PS = R"(
    float4 main() : SV_TARGET {
        return float4(0.2f, 0.4f, 0.8f, 1.0f);
    }
)";

int main() {
    // 初始化 COM
    CoInitializeEx(nullptr, COINIT_APARTMENTTHREADED);

    // 创建设备和上下文
    ComPtr<ID3D11Device> device;
    ComPtr<ID3D11DeviceContext> context;
    D3D11CreateDevice(
        nullptr, D3D_DRIVER_TYPE_HARDWARE, nullptr, D3D11_CREATE_DEVICE_DEBUG, nullptr, 0, D3D11_SDK_VERSION, &device, nullptr, &context);

    // 创建交换链（窗口可选，这里仅用于渲染上下文）
    ComPtr<IDXGISwapChain> swapChain;
    DXGI_SWAP_CHAIN_DESC sd = {};
    sd.BufferDesc.Width = Width;
    sd.BufferDesc.Height = Height;
    sd.BufferDesc.Format = DXGI_FORMAT_R8G8B8A8_UNORM;
    sd.SampleDesc.Count = 1;
    sd.BufferUsage = DXGI_USAGE_RENDER_TARGET_OUTPUT;
    sd.BufferCount = 1;
    sd.OutputWindow = GetConsoleWindow(); // 或创建窗口
    sd.Windowed = TRUE;

    ComPtr<IDXGIDevice> dxgiDevice;
    device.As(&dxgiDevice);
    ComPtr<IDXGIAdapter> adapter;
    dxgiDevice->GetAdapter(&adapter);
    ComPtr<IDXGIFactory> factory;
    adapter->GetParent(IID_PPV_ARGS(&factory));
    factory->CreateSwapChain(device.Get(), &sd, &swapChain);

    // 创建渲染目标
    ComPtr<ID3D11RenderTargetView> rtv;
    ComPtr<ID3D11Texture2D> backBuffer;
    swapChain->GetBuffer(0, IID_PPV_ARGS(&backBuffer));
    device->CreateRenderTargetView(backBuffer.Get(), nullptr, &rtv);

    // 创建深度缓冲（D32_FLOAT）
    ComPtr<ID3D11Texture2D> depthBuffer;
    D3D11_TEXTURE2D_DESC depthDesc = {};
    depthDesc.Width = Width;
    depthDesc.Height = Height;
    depthDesc.MipLevels = 1;
    depthDesc.ArraySize = 1;
    depthDesc.Format = DXGI_FORMAT_D32_FLOAT;
    depthDesc.SampleDesc.Count = 1;
    depthDesc.Usage = D3D11_USAGE_DEFAULT;
    depthDesc.BindFlags = D3D11_BIND_DEPTH_STENCIL;
    device->CreateTexture2D(&depthDesc, nullptr, &depthBuffer);

    ComPtr<ID3D11DepthStencilView> dsv;
    device->CreateDepthStencilView(depthBuffer.Get(), nullptr, &dsv);

    // 创建 staging texture 用于 CPU 读取深度（R32_FLOAT）
    ComPtr<ID3D11Texture2D> depthStaging;
    D3D11_TEXTURE2D_DESC stagingDesc = depthDesc;
    stagingDesc.Format = DXGI_FORMAT_R32_FLOAT; // 注意：DSV 用 D32_FLOAT，staging 用 R32_FLOAT
    stagingDesc.BindFlags = 0;
    stagingDesc.CPUAccessFlags = D3D11_CPU_ACCESS_READ;
    stagingDesc.Usage = D3D11_USAGE_STAGING;
    device->CreateTexture2D(&stagingDesc, nullptr, &depthStaging);

    // 编译并创建着色器
    ComPtr<ID3D11VertexShader> vs;
    ComPtr<ID3D11PixelShader> ps;
    ComPtr<ID3DBlob> vsBlob, psBlob;
    D3DCompile(g_VS, strlen(g_VS), nullptr, nullptr, nullptr, "main", "vs_4_0", 0, 0, &vsBlob, nullptr);
    D3DCompile(g_PS, strlen(g_PS), nullptr, nullptr, nullptr, "main", "ps_4_0", 0, 0, &psBlob, nullptr);
    device->CreateVertexShader(vsBlob->GetBufferPointer(), vsBlob->GetBufferSize(), nullptr, &vs);
    device->CreatePixelShader(psBlob->GetBufferPointer(), psBlob->GetBufferSize(), nullptr, &ps);

    // 输入布局
    D3D11_INPUT_ELEMENT_DESC layout[] = {{"POSITION", 0, DXGI_FORMAT_R32G32B32_FLOAT, 0, 0, D3D11_INPUT_PER_VERTEX_DATA, 0}};
    ComPtr<ID3D11InputLayout> inputLayout;
    device->CreateInputLayout(layout, 1, vsBlob->GetBufferPointer(), vsBlob->GetBufferSize(), &inputLayout);

    // 顶点缓冲
    ComPtr<ID3D11Buffer> vertexBuffer;
    D3D11_BUFFER_DESC vbDesc = {};
    vbDesc.ByteWidth = sizeof(CubeVertices);
    vbDesc.Usage = D3D11_USAGE_DEFAULT;
    vbDesc.BindFlags = D3D11_BIND_VERTEX_BUFFER;
    D3D11_SUBRESOURCE_DATA vbData = {CubeVertices};
    device->CreateBuffer(&vbDesc, &vbData, &vertexBuffer);

    // 深度测试启用
    ComPtr<ID3D11DepthStencilState> depthState;
    D3D11_DEPTH_STENCIL_DESC dsDesc = {};
    dsDesc.DepthEnable = TRUE;
    dsDesc.DepthWriteMask = D3D11_DEPTH_WRITE_MASK_ALL;
    dsDesc.DepthFunc = D3D11_COMPARISON_LESS;
    device->CreateDepthStencilState(&dsDesc, &depthState);

    // 视口
    D3D11_VIEWPORT vp = {0, 0, (float) Width, (float) Height, 0, 1};
    context->RSSetViewports(1, &vp);

    // 打开命名管道（需另一进程已创建）
    HANDLE hPipe = CreateFileW(PipeName, GENERIC_WRITE, 0, nullptr, OPEN_EXISTING, 0, nullptr);

    if (hPipe == INVALID_HANDLE_VALUE) {
        std::cerr << "Failed to open named pipe. Ensure another process created it.\n";
        return -1;
    }

    constexpr size_t depthSize = Width * Height * sizeof(float);
    std::vector<BYTE> depthData(depthSize);

    // 渲染循环（示例只渲染10帧）
    for (int frame = 0; frame < 10; ++frame) {
        // 清屏
        float clearColor[] = {0.1f, 0.1f, 0.1f, 1.0f};
        context->ClearRenderTargetView(rtv.Get(), clearColor);
        context->ClearDepthStencilView(dsv.Get(), D3D11_CLEAR_DEPTH, 1.0f, 0);

        // 设置管线
        context->OMSetRenderTargets(1, rtv.GetAddressOf(), dsv.Get());
        context->OMSetDepthStencilState(depthState.Get(), 1);
        context->VSSetShader(vs.Get(), nullptr, 0);
        context->PSSetShader(ps.Get(), nullptr, 0);
        context->IASetInputLayout(inputLayout.Get());
        UINT stride = sizeof(Vertex), offset = 0;
        context->IASetVertexBuffers(0, 1, vertexBuffer.GetAddressOf(), &stride, &offset);
        context->IASetPrimitiveTopology(D3D11_PRIMITIVE_TOPOLOGY_TRIANGLELIST);

        // 绘制立方体
        context->Draw(6, 0); // 仅前面，实际应为36

        // 复制深度缓冲到 staging texture
        context->CopyResource(depthStaging.Get(), depthBuffer.Get());

        // Map 获取数据
        D3D11_MAPPED_SUBRESOURCE mapped;
        context->Map(depthStaging.Get(), 0, D3D11_MAP_READ, 0, &mapped);
        memcpy(depthData.data(), mapped.pData, depthSize);
        context->Unmap(depthStaging.Get(), 0);

        // 写入命名管道
        DWORD written;
        if (!WriteFile(hPipe, depthData.data(), static_cast<DWORD>(depthSize), &written, nullptr) || written != depthSize) {
            std::cerr << "WriteFile failed or incomplete.\n";
            break;
        }

        // 呈现（可选）
        swapChain->Present(0, 0);
    }

    CloseHandle(hPipe);
    CoUninitialize();
    return 0;
}

using ::Basalt::Shared::Engine::EngineConfig;
using ::Basalt::Shared::Engine::IEngine;

class DirectX11Engine : public IEngine {
public:
    DirectX11Engine() : IEngine() {}
    virtual ~DirectX11Engine() {}

private:
    ComPtr<ID3D11Device> device; ///< 设备
    ComPtr<ID3D11DeviceContext> context; ///< 上下文
    ComPtr<IDXGISwapChain> swapChain; ///< 交换链


public:
    virtual void Startup(EngineConfig&& config) override { IEngine::Startup(std::move(config)); }
    virtual void Tick() override { IEngine::Tick(); }
    virtual void Shutdown() override { IEngine::Shutdown(); }
};

BS_EXPORT void* BSCreateInstance() {
    return new DirectX11Engine();
}

BS_EXPORT void BSDestroyInstance(void* instance) {
    delete reinterpret_cast<DirectX11Engine*>(instance);
}