#define NOMINMAX
#include <windows.h>

#include <gtest/gtest.h>

#include "../RenderingIntegrationMain.h"

#include <XCEngine/Components/CameraComponent.h>
#include <XCEngine/Components/GameObject.h>
#include <XCEngine/Core/Asset/IResource.h>
#include <XCEngine/Core/Math/Color.h>
#include <XCEngine/Core/Math/Quaternion.h>
#include <XCEngine/Core/Math/Vector3.h>
#include <XCEngine/Core/Math/Vector4.h>
#include <XCEngine/Rendering/Execution/SceneRenderer.h>
#include <XCEngine/Rendering/RenderContext.h>
#include <XCEngine/Rendering/RenderSurface.h>
#include <XCEngine/Resources/BuiltinResources.h>
#include <XCEngine/Resources/Material/Material.h>
#include <XCEngine/Resources/Shader/Shader.h>
#include <XCEngine/Resources/Texture/Texture.h>
#include <XCEngine/Resources/Texture/TextureImportSettings.h>
#include <XCEngine/Resources/Texture/TextureLoader.h>
#include <XCEngine/RHI/RHITexture.h>
#include <XCEngine/Scene/Scene.h>

#include "../../../RHI/integration/fixtures/RHIIntegrationFixture.h"

#include <algorithm>
#include <filesystem>
#include <memory>
#include <vector>

using namespace XCEngine::Components;
using namespace XCEngine::Math;
using namespace XCEngine::Rendering;
using namespace XCEngine::Resources;
using namespace XCEngine::RHI;
using namespace XCEngine::RHI::Integration;

namespace {

constexpr const char* kD3D12Screenshot = "skybox_scene_d3d12.ppm";
constexpr const char* kOpenGLScreenshot = "skybox_scene_opengl.ppm";
constexpr const char* kVulkanScreenshot = "skybox_scene_vulkan.ppm";
constexpr uint32_t kFrameWidth = 1280;
constexpr uint32_t kFrameHeight = 720;

std::filesystem::path GetExecutableDirectory() {
    char exePath[MAX_PATH] = {};
    const DWORD length = GetModuleFileNameA(nullptr, exePath, MAX_PATH);
    if (length == 0 || length >= MAX_PATH) {
        return std::filesystem::current_path();
    }

    return std::filesystem::path(exePath).parent_path();
}

std::filesystem::path ResolveRuntimePath(const char* relativePath) {
    return GetExecutableDirectory() / relativePath;
}

Texture* LoadPanoramicSkyboxTexture(const std::filesystem::path& panoramaPath) {
    TextureLoader loader;
    TextureImportSettings settings;
    settings.SetSRGB(true);

    LoadResult loadResult = loader.Load(panoramaPath.string().c_str(), &settings);
    if (!loadResult || loadResult.resource == nullptr) {
        return nullptr;
    }

    auto* texture = static_cast<Texture*>(loadResult.resource);
    if (texture == nullptr ||
        texture->GetPixelData() == nullptr ||
        texture->GetWidth() == 0 ||
        texture->GetHeight() == 0) {
        delete texture;
        return nullptr;
    }

    return texture;
}

Material* CreateSkyboxMaterial(Texture* texture) {
    auto* material = new Material();
    IResource::ConstructParams params = {};
    params.name = "SkyboxPanoramicMaterial";
    params.path = "Tests/Rendering/SkyboxScene/skybox_panorama.mat";
    params.guid = ResourceGUID::Generate(params.path);
    material->Initialize(params);
    material->SetShader(ResourceManager::Get().Load<Shader>(GetBuiltinSkyboxShaderPath()));
    material->SetTexture("_MainTex", ResourceHandle<Texture>(texture));
    material->SetFloat4("_Tint", Vector4(1.0f, 1.0f, 1.0f, 1.0f));
    material->SetFloat("_Exposure", 1.0f);
    material->SetFloat("_Rotation", -90.0f);
    return material;
}

const char* GetScreenshotFilename(RHIType backendType) {
    switch (backendType) {
        case RHIType::D3D12:
            return kD3D12Screenshot;
        case RHIType::Vulkan:
            return kVulkanScreenshot;
        case RHIType::OpenGL:
        default:
            return kOpenGLScreenshot;
    }
}

int GetComparisonThreshold(RHIType backendType) {
    (void)backendType;
    return 10;
}

class SkyboxSceneTest : public RHIIntegrationFixture {
protected:
    void SetUp() override;
    void TearDown() override;
    void RenderFrame() override;

private:
    void BuildScene();
    RHIResourceView* GetCurrentBackBufferView();

    std::unique_ptr<Scene> mScene;
    std::unique_ptr<SceneRenderer> mSceneRenderer;
    std::vector<RHIResourceView*> mBackBufferViews;
    std::vector<Material*> mMaterials;
    std::vector<Texture*> mTextures;
    RHITexture* mDepthTexture = nullptr;
    RHIResourceView* mDepthView = nullptr;
};

void SkyboxSceneTest::SetUp() {
    RHIIntegrationFixture::SetUp();

    mSceneRenderer = std::make_unique<SceneRenderer>();
    mScene = std::make_unique<Scene>("SkyboxScene");

    BuildScene();

    TextureDesc depthDesc = {};
    depthDesc.width = kFrameWidth;
    depthDesc.height = kFrameHeight;
    depthDesc.depth = 1;
    depthDesc.mipLevels = 1;
    depthDesc.arraySize = 1;
    depthDesc.format = static_cast<uint32_t>(Format::D24_UNorm_S8_UInt);
    depthDesc.textureType = static_cast<uint32_t>(XCEngine::RHI::TextureType::Texture2D);
    depthDesc.sampleCount = 1;
    depthDesc.sampleQuality = 0;
    depthDesc.flags = 0;
    mDepthTexture = GetDevice()->CreateTexture(depthDesc);
    ASSERT_NE(mDepthTexture, nullptr);

    ResourceViewDesc depthViewDesc = {};
    depthViewDesc.format = static_cast<uint32_t>(Format::D24_UNorm_S8_UInt);
    depthViewDesc.dimension = ResourceViewDimension::Texture2D;
    depthViewDesc.mipLevel = 0;
    mDepthView = GetDevice()->CreateDepthStencilView(mDepthTexture, depthViewDesc);
    ASSERT_NE(mDepthView, nullptr);

    mBackBufferViews.resize(2, nullptr);
}

void SkyboxSceneTest::TearDown() {
    mSceneRenderer.reset();

    if (mDepthView != nullptr) {
        mDepthView->Shutdown();
        delete mDepthView;
        mDepthView = nullptr;
    }

    if (mDepthTexture != nullptr) {
        mDepthTexture->Shutdown();
        delete mDepthTexture;
        mDepthTexture = nullptr;
    }

    for (RHIResourceView*& backBufferView : mBackBufferViews) {
        if (backBufferView != nullptr) {
            backBufferView->Shutdown();
            delete backBufferView;
            backBufferView = nullptr;
        }
    }
    mBackBufferViews.clear();

    mScene.reset();

    for (Material* material : mMaterials) {
        delete material;
    }
    mMaterials.clear();

    for (Texture* texture : mTextures) {
        delete texture;
    }
    mTextures.clear();
    RHIIntegrationFixture::TearDown();
}

void SkyboxSceneTest::BuildScene() {
    ASSERT_NE(mScene, nullptr);

    GameObject* cameraObject = mScene->CreateGameObject("MainCamera");
    auto* camera = cameraObject->AddComponent<CameraComponent>();
    camera->SetPrimary(true);
    camera->SetProjectionType(CameraProjectionType::Perspective);
    camera->SetFieldOfView(90.0f);
    camera->SetNearClipPlane(0.1f);
    camera->SetFarClipPlane(20.0f);
    camera->SetClearColor(XCEngine::Math::Color(0.01f, 0.01f, 0.01f, 1.0f));
    camera->SetSkyboxEnabled(true);
    Texture* skyboxTexture = LoadPanoramicSkyboxTexture(ResolveRuntimePath("Res/skyboxes/sky.png"));
    ASSERT_NE(skyboxTexture, nullptr);
    Material* skyboxMaterial = CreateSkyboxMaterial(skyboxTexture);
    ASSERT_NE(skyboxMaterial, nullptr);
    camera->SetSkyboxMaterial(skyboxMaterial);

    mMaterials = { skyboxMaterial };
    mTextures = { skyboxTexture };
}

RHIResourceView* SkyboxSceneTest::GetCurrentBackBufferView() {
    const int backBufferIndex = GetCurrentBackBufferIndex();
    if (backBufferIndex < 0) {
        return nullptr;
    }

    if (static_cast<size_t>(backBufferIndex) >= mBackBufferViews.size()) {
        mBackBufferViews.resize(static_cast<size_t>(backBufferIndex) + 1, nullptr);
    }

    if (mBackBufferViews[backBufferIndex] == nullptr) {
        ResourceViewDesc viewDesc = {};
        viewDesc.format = static_cast<uint32_t>(Format::R8G8B8A8_UNorm);
        viewDesc.dimension = ResourceViewDimension::Texture2D;
        viewDesc.mipLevel = 0;
        mBackBufferViews[backBufferIndex] = GetDevice()->CreateRenderTargetView(GetCurrentBackBuffer(), viewDesc);
    }

    return mBackBufferViews[backBufferIndex];
}

void SkyboxSceneTest::RenderFrame() {
    ASSERT_NE(mScene, nullptr);
    ASSERT_NE(mSceneRenderer, nullptr);

    RHICommandList* commandList = GetCommandList();
    ASSERT_NE(commandList, nullptr);

    commandList->Reset();

    RenderSurface surface(kFrameWidth, kFrameHeight);
    surface.SetColorAttachment(GetCurrentBackBufferView());
    surface.SetDepthAttachment(mDepthView);

    RenderContext renderContext = {};
    renderContext.device = GetDevice();
    renderContext.commandList = commandList;
    renderContext.commandQueue = GetCommandQueue();
    renderContext.backendType = GetBackendType();

    ASSERT_TRUE(mSceneRenderer->Render(*mScene, nullptr, renderContext, surface));

    commandList->Close();
    void* commandLists[] = { commandList };
    GetCommandQueue()->ExecuteCommandLists(1, commandLists);
}

TEST_P(SkyboxSceneTest, RenderSkyboxScene) {
    RHICommandQueue* commandQueue = GetCommandQueue();
    RHISwapChain* swapChain = GetSwapChain();
    const int targetFrameCount = 30;
    const char* screenshotFilename = GetScreenshotFilename(GetBackendType());
    const int comparisonThreshold = GetComparisonThreshold(GetBackendType());

    for (int frameCount = 0; frameCount <= targetFrameCount; ++frameCount) {
        if (frameCount > 0) {
            commandQueue->WaitForPreviousFrame();
        }

        BeginRender();
        RenderFrame();

        if (frameCount >= targetFrameCount) {
            commandQueue->WaitForIdle();
            ASSERT_TRUE(TakeScreenshot(screenshotFilename));
            ASSERT_TRUE(CompareWithGoldenTemplate(screenshotFilename, "GT.ppm", static_cast<float>(comparisonThreshold)));
            break;
        }

        swapChain->Present(0, 0);
    }
}

} // namespace

INSTANTIATE_TEST_SUITE_P(D3D12, SkyboxSceneTest, ::testing::Values(RHIType::D3D12));
INSTANTIATE_TEST_SUITE_P(OpenGL, SkyboxSceneTest, ::testing::Values(RHIType::OpenGL));
#if defined(XCENGINE_SUPPORT_VULKAN)
INSTANTIATE_TEST_SUITE_P(Vulkan, SkyboxSceneTest, ::testing::Values(RHIType::Vulkan));
#endif

GTEST_API_ int main(int argc, char** argv) {
    return RunRenderingIntegrationTestMain(argc, argv);
}