#define NOMINMAX
#include <windows.h>

#include <gtest/gtest.h>

#include "../RenderingIntegrationMain.h"

#include <XCEngine/Components/CameraComponent.h>
#include <XCEngine/Components/GameObject.h>
#include <XCEngine/Components/LightComponent.h>
#include <XCEngine/Components/MeshFilterComponent.h>
#include <XCEngine/Components/MeshRendererComponent.h>
#include <XCEngine/Core/Asset/IResource.h>
#include <XCEngine/Core/Math/Color.h>
#include <XCEngine/Core/Math/Quaternion.h>
#include <XCEngine/Core/Math/Vector2.h>
#include <XCEngine/Core/Math/Vector3.h>
#include <XCEngine/Debug/ConsoleLogSink.h>
#include <XCEngine/Debug/Logger.h>
#include <XCEngine/Rendering/RenderContext.h>
#include <XCEngine/Rendering/RenderPass.h>
#include <XCEngine/Rendering/RenderSurface.h>
#include <XCEngine/Rendering/SceneRenderer.h>
#include <XCEngine/Resources/BuiltinResources.h>
#include <XCEngine/Resources/Material/Material.h>
#include <XCEngine/Resources/Mesh/Mesh.h>
#include <XCEngine/Resources/Shader/Shader.h>
#include <XCEngine/RHI/RHIDescriptorPool.h>
#include <XCEngine/RHI/RHIDescriptorSet.h>
#include <XCEngine/RHI/RHIPipelineLayout.h>
#include <XCEngine/RHI/RHIPipelineState.h>
#include <XCEngine/RHI/RHISampler.h>
#include <XCEngine/RHI/RHITexture.h>
#include <XCEngine/Scene/Scene.h>

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

#include <cstring>
#include <memory>
#include <vector>

using namespace XCEngine::Components;
using namespace XCEngine::Debug;
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 = "directional_shadow_scene_d3d12.ppm";
constexpr const char* kOpenGLScreenshot = "directional_shadow_scene_opengl.ppm";
constexpr const char* kVulkanScreenshot = "directional_shadow_scene_vulkan.ppm";
constexpr uint32_t kFrameWidth = 1280;
constexpr uint32_t kFrameHeight = 720;

void AppendQuadFace(
    std::vector<StaticMeshVertex>& vertices,
    std::vector<uint32_t>& indices,
    const Vector3& v0,
    const Vector3& v1,
    const Vector3& v2,
    const Vector3& v3,
    const Vector3& normal) {
    const uint32_t baseIndex = static_cast<uint32_t>(vertices.size());

    StaticMeshVertex vertex = {};
    vertex.normal = normal;

    vertex.position = v0;
    vertex.uv0 = Vector2(0.0f, 1.0f);
    vertices.push_back(vertex);

    vertex.position = v1;
    vertex.uv0 = Vector2(1.0f, 1.0f);
    vertices.push_back(vertex);

    vertex.position = v2;
    vertex.uv0 = Vector2(0.0f, 0.0f);
    vertices.push_back(vertex);

    vertex.position = v3;
    vertex.uv0 = Vector2(1.0f, 0.0f);
    vertices.push_back(vertex);

    indices.push_back(baseIndex + 0);
    indices.push_back(baseIndex + 2);
    indices.push_back(baseIndex + 1);
    indices.push_back(baseIndex + 1);
    indices.push_back(baseIndex + 2);
    indices.push_back(baseIndex + 3);
}

Mesh* CreateGroundMesh() {
    auto* mesh = new Mesh();
    IResource::ConstructParams params = {};
    params.name = "DirectionalShadowGroundMesh";
    params.path = "Tests/Rendering/DirectionalShadowGround.mesh";
    params.guid = ResourceGUID::Generate(params.path);
    mesh->Initialize(params);

    StaticMeshVertex vertices[4] = {};
    vertices[0].position = Vector3(-12.0f, 0.0f, 1.0f);
    vertices[0].normal = Vector3::Up();
    vertices[0].uv0 = Vector2(0.0f, 1.0f);
    vertices[1].position = Vector3(-12.0f, 0.0f, 20.0f);
    vertices[1].normal = Vector3::Up();
    vertices[1].uv0 = Vector2(0.0f, 0.0f);
    vertices[2].position = Vector3(12.0f, 0.0f, 1.0f);
    vertices[2].normal = Vector3::Up();
    vertices[2].uv0 = Vector2(1.0f, 1.0f);
    vertices[3].position = Vector3(12.0f, 0.0f, 20.0f);
    vertices[3].normal = Vector3::Up();
    vertices[3].uv0 = Vector2(1.0f, 0.0f);

    const uint32_t indices[6] = { 0, 1, 2, 2, 1, 3 };

    mesh->SetVertexData(
        vertices,
        sizeof(vertices),
        4,
        sizeof(StaticMeshVertex),
        VertexAttribute::Position | VertexAttribute::Normal | VertexAttribute::UV0);
    mesh->SetIndexData(indices, sizeof(indices), 6, true);
    const Bounds bounds(Vector3(0.0f, 0.0f, 10.5f), Vector3(24.0f, 0.1f, 19.0f));
    mesh->SetBounds(bounds);

    MeshSection section = {};
    section.baseVertex = 0;
    section.vertexCount = 4;
    section.startIndex = 0;
    section.indexCount = 6;
    section.materialID = 0;
    section.bounds = bounds;
    mesh->AddSection(section);
    return mesh;
}

Mesh* CreateCubeMesh() {
    auto* mesh = new Mesh();
    IResource::ConstructParams params = {};
    params.name = "DirectionalShadowCubeMesh";
    params.path = "Tests/Rendering/DirectionalShadowCube.mesh";
    params.guid = ResourceGUID::Generate(params.path);
    mesh->Initialize(params);

    std::vector<StaticMeshVertex> vertices;
    std::vector<uint32_t> indices;
    vertices.reserve(24);
    indices.reserve(36);

    constexpr float half = 0.5f;
    AppendQuadFace(
        vertices, indices,
        Vector3(-half, -half, half),
        Vector3(half, -half, half),
        Vector3(-half, half, half),
        Vector3(half, half, half),
        Vector3::Forward());
    AppendQuadFace(
        vertices, indices,
        Vector3(half, -half, -half),
        Vector3(-half, -half, -half),
        Vector3(half, half, -half),
        Vector3(-half, half, -half),
        Vector3::Back());
    AppendQuadFace(
        vertices, indices,
        Vector3(-half, -half, -half),
        Vector3(-half, -half, half),
        Vector3(-half, half, -half),
        Vector3(-half, half, half),
        Vector3::Left());
    AppendQuadFace(
        vertices, indices,
        Vector3(half, -half, half),
        Vector3(half, -half, -half),
        Vector3(half, half, half),
        Vector3(half, half, -half),
        Vector3::Right());
    AppendQuadFace(
        vertices, indices,
        Vector3(-half, half, half),
        Vector3(half, half, half),
        Vector3(-half, half, -half),
        Vector3(half, half, -half),
        Vector3::Up());
    AppendQuadFace(
        vertices, indices,
        Vector3(-half, -half, -half),
        Vector3(half, -half, -half),
        Vector3(-half, -half, half),
        Vector3(half, -half, half),
        Vector3::Down());

    mesh->SetVertexData(
        vertices.data(),
        vertices.size() * sizeof(StaticMeshVertex),
        static_cast<uint32_t>(vertices.size()),
        sizeof(StaticMeshVertex),
        VertexAttribute::Position | VertexAttribute::Normal | VertexAttribute::UV0);
    mesh->SetIndexData(
        indices.data(),
        indices.size() * sizeof(uint32_t),
        static_cast<uint32_t>(indices.size()),
        true);
    const Bounds bounds(Vector3::Zero(), Vector3::One());
    mesh->SetBounds(bounds);

    MeshSection section = {};
    section.baseVertex = 0;
    section.vertexCount = static_cast<uint32_t>(vertices.size());
    section.startIndex = 0;
    section.indexCount = static_cast<uint32_t>(indices.size());
    section.materialID = 0;
    section.bounds = bounds;
    mesh->AddSection(section);
    return mesh;
}

Material* CreateForwardLitMaterial(
    const char* name,
    const char* path,
    const Vector4& baseColor) {
    auto* material = new Material();
    IResource::ConstructParams params = {};
    params.name = name;
    params.path = path;
    params.guid = ResourceGUID::Generate(params.path);
    material->Initialize(params);
    material->SetShader(ResourceManager::Get().Load<Shader>(GetBuiltinForwardLitShaderPath()));
    material->SetShaderPass("ForwardLit");
    material->SetFloat4("_BaseColor", baseColor);
    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) {
    return backendType == RHIType::D3D12 ? 10 : 10;
}

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

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

    std::unique_ptr<Scene> mScene;
    std::unique_ptr<SceneRenderer> mSceneRenderer;
    std::vector<RHIResourceView*> mBackBufferViews;
    RHITexture* mDepthTexture = nullptr;
    RHIResourceView* mDepthView = nullptr;
    Mesh* mGroundMesh = nullptr;
    Mesh* mCubeMesh = nullptr;
    Material* mGroundMaterial = nullptr;
    Material* mCasterMaterial = nullptr;
};

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

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

    mGroundMesh = CreateGroundMesh();
    ASSERT_NE(mGroundMesh, nullptr);

    mCubeMesh = CreateCubeMesh();
    ASSERT_NE(mCubeMesh, nullptr);

    mGroundMaterial = CreateForwardLitMaterial(
        "DirectionalShadowGround",
        "Tests/Rendering/DirectionalShadowGround.material",
        Vector4(0.92f, 0.93f, 0.96f, 1.0f));
    mCasterMaterial = CreateForwardLitMaterial(
        "DirectionalShadowCaster",
        "Tests/Rendering/DirectionalShadowCaster.material",
        Vector4(0.72f, 0.22f, 0.16f, 1.0f));

    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 DirectionalShadowSceneTest::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();

    delete mGroundMaterial;
    mGroundMaterial = nullptr;
    delete mCasterMaterial;
    mCasterMaterial = nullptr;
    delete mGroundMesh;
    mGroundMesh = nullptr;
    delete mCubeMesh;
    mCubeMesh = nullptr;

    RHIIntegrationFixture::TearDown();
}

void DirectionalShadowSceneTest::BuildScene() {
    ASSERT_NE(mScene, nullptr);
    ASSERT_NE(mGroundMesh, nullptr);
    ASSERT_NE(mCubeMesh, nullptr);
    ASSERT_NE(mGroundMaterial, nullptr);
    ASSERT_NE(mCasterMaterial, nullptr);

    GameObject* cameraObject = mScene->CreateGameObject("MainCamera");
    auto* camera = cameraObject->AddComponent<CameraComponent>();
    camera->SetPrimary(true);
    camera->SetFieldOfView(42.0f);
    camera->SetNearClipPlane(0.1f);
    camera->SetFarClipPlane(40.0f);
    camera->SetClearColor(XCEngine::Math::Color(0.03f, 0.03f, 0.05f, 1.0f));
    cameraObject->GetTransform()->SetLocalPosition(Vector3(0.2f, 3.4f, -7.2f));
    cameraObject->GetTransform()->SetLocalRotation(
        Quaternion::LookRotation(Vector3(-0.12f, -0.14f, 1.0f).Normalized()));

    GameObject* lightObject = mScene->CreateGameObject("MainDirectionalLight");
    auto* light = lightObject->AddComponent<LightComponent>();
    light->SetLightType(LightType::Directional);
    light->SetColor(XCEngine::Math::Color(1.0f, 1.0f, 0.97f, 1.0f));
    light->SetIntensity(2.3f);
    light->SetCastsShadows(true);
    lightObject->GetTransform()->SetLocalRotation(
        Quaternion::LookRotation(Vector3(0.84f, -0.52f, -0.14f).Normalized()));

    GameObject* groundObject = mScene->CreateGameObject("Ground");
    auto* groundMeshFilter = groundObject->AddComponent<MeshFilterComponent>();
    auto* groundMeshRenderer = groundObject->AddComponent<MeshRendererComponent>();
    groundObject->GetTransform()->SetLocalPosition(Vector3(0.0f, -0.18f, 10.5f));
    groundObject->GetTransform()->SetLocalScale(Vector3(12.0f, 0.18f, 9.5f));
    groundMeshFilter->SetMesh(ResourceHandle<Mesh>(mCubeMesh));
    groundMeshRenderer->SetMaterial(0, mGroundMaterial);
    groundMeshRenderer->SetCastShadows(false);
    groundMeshRenderer->SetReceiveShadows(true);

    GameObject* casterObject = mScene->CreateGameObject("CasterCube");
    casterObject->GetTransform()->SetLocalPosition(Vector3(-1.2f, 1.71f, 8.8f));
    casterObject->GetTransform()->SetLocalScale(Vector3(1.8f, 3.6f, 1.8f));
    auto* casterMeshFilter = casterObject->AddComponent<MeshFilterComponent>();
    auto* casterMeshRenderer = casterObject->AddComponent<MeshRendererComponent>();
    casterMeshFilter->SetMesh(ResourceHandle<Mesh>(mCubeMesh));
    casterMeshRenderer->SetMaterial(0, mCasterMaterial);
    casterMeshRenderer->SetCastShadows(true);
    casterMeshRenderer->SetReceiveShadows(true);
}

RHIResourceView* DirectionalShadowSceneTest::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 DirectionalShadowSceneTest::RenderFrame() {
    RenderSceneFrame();
}

void DirectionalShadowSceneTest::RenderSceneFrame() {
    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();

    std::vector<CameraRenderRequest> requests =
        mSceneRenderer->BuildRenderRequests(*mScene, nullptr, renderContext, surface);
    ASSERT_FALSE(requests.empty());
    ASSERT_TRUE(mSceneRenderer->Render(requests));

    Log("[TEST] DirectionalShadowSceneTest: closing command list");
    commandList->Close();
    void* commandLists[] = { commandList };
    Log("[TEST] DirectionalShadowSceneTest: executing command list");
    GetCommandQueue()->ExecuteCommandLists(1, commandLists);
    Log("[TEST] DirectionalShadowSceneTest: execute submitted");
}

TEST_P(DirectionalShadowSceneTest, RenderDirectionalShadowScene) {
    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, DirectionalShadowSceneTest, ::testing::Values(RHIType::D3D12));
INSTANTIATE_TEST_SUITE_P(OpenGL, DirectionalShadowSceneTest, ::testing::Values(RHIType::OpenGL));
#if defined(XCENGINE_SUPPORT_VULKAN)
INSTANTIATE_TEST_SUITE_P(Vulkan, DirectionalShadowSceneTest, ::testing::Values(RHIType::Vulkan));
#endif

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