#include "MetaCoreRender/MetaCoreRenderDevice.h"

#include "MetaCorePlatform/MetaCoreWindow.h"

#include "camera.h"
#include "displayRegion.h"
#include "graphicsEngine.h"
#include "graphicsWindow.h"
#include "pandaFramework.h"
#include "pandaNode.h"
#include "perspectiveLens.h"
#include "windowFramework.h"

#include <glm/mat4x4.hpp>

#include <algorithm>
#include <memory>

namespace MetaCore {

namespace {

glm::mat4 MetaCoreConvertPandaMatrixToGlm(const LMatrix4f& matrix) {
    glm::mat4 result(1.0F);
    for (int col = 0; col < 4; ++col) {
        for (int row = 0; row < 4; ++row) {
            // Transpose mathematical matrix: result[col][row] is GLM(row, col).
            // We want GLM(row, col) = Panda(col, row) to switch v*M to M*v.
            result[col][row] = matrix.get_cell(col, row);
        }
    }
    return result;
}

}  // namespace

class MetaCoreRenderDevice::MetaCoreRenderDeviceImpl {
public:
    MetaCoreWindow* Window = nullptr;
    PandaFramework* Framework = nullptr;
    WindowFramework* WindowFrameworkHandle = nullptr;
    GraphicsWindow* GraphicsWindowHandle = nullptr;
    GraphicsEngine* GraphicsEngineHandle = nullptr;
    DisplayRegion* SceneDisplayRegion = nullptr;
    NodePath SceneRoot{};
    NodePath EditorCamera{};
    bool Initialized = false;
};

MetaCoreRenderDevice::MetaCoreRenderDevice()
    : Impl_(std::make_unique<MetaCoreRenderDeviceImpl>()) {
}

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

bool MetaCoreRenderDevice::Initialize(MetaCoreWindow& window) {
    if (Impl_->Initialized) {
        return true;
    }
    Impl_->Window = &window;
    Impl_->Initialized = true;
    return true;
}

void MetaCoreRenderDevice::Shutdown() {
    if (!Impl_->Initialized) {
        return;
    }

    if (!Impl_->EditorCamera.is_empty()) {
        Impl_->EditorCamera.remove_node();
        Impl_->EditorCamera = NodePath();
    }

    if (!Impl_->SceneRoot.is_empty()) {
        Impl_->SceneRoot.remove_node();
        Impl_->SceneRoot = NodePath();
    }

    Impl_->SceneDisplayRegion = nullptr;
    Impl_->GraphicsEngineHandle = nullptr;
    Impl_->GraphicsWindowHandle = nullptr;
    Impl_->WindowFrameworkHandle = nullptr;
    Impl_->Framework = nullptr;
    Impl_->Window = nullptr;
    Impl_->Initialized = false;
}

void MetaCoreRenderDevice::RenderFrame() const {
    if (Impl_->GraphicsEngineHandle != nullptr) {
        Impl_->GraphicsEngineHandle->render_frame();
    }
}

void MetaCoreRenderDevice::PresentFrame() const {
    if (Impl_->GraphicsEngineHandle != nullptr) {
        Impl_->GraphicsEngineHandle->flip_frame();
    }
}

void MetaCoreRenderDevice::SetSceneViewportRect(const MetaCoreViewportRect& viewportRect) {
    // 已废弃 Panda3D 实现，视口管理已移至 Filament 链
}

}  // namespace MetaCore