#pragma once

#include <XCEngine/UI/DrawData.h>
#include <XCEngine/UI/Types.h>

#include <memory>
#include <vector>

namespace XCEngine::UI::Editor::App {

class EditorSceneRuntime;

struct SceneViewportTransformGizmoTriangle {
    ::XCEngine::UI::UIPoint a = {};
    ::XCEngine::UI::UIPoint b = {};
    ::XCEngine::UI::UIPoint c = {};
    ::XCEngine::UI::UIColor color = {};
};

struct SceneViewportTransformGizmoFrame {
    bool visible = false;
    ::XCEngine::UI::UIRect clipRect = {};
    std::vector<SceneViewportTransformGizmoTriangle> triangles = {};
};

class SceneViewportTransformGizmo {
public:
    SceneViewportTransformGizmo();
    ~SceneViewportTransformGizmo();

    SceneViewportTransformGizmo(const SceneViewportTransformGizmo&) = delete;
    SceneViewportTransformGizmo& operator=(const SceneViewportTransformGizmo&) = delete;
    SceneViewportTransformGizmo(SceneViewportTransformGizmo&&) noexcept;
    SceneViewportTransformGizmo& operator=(SceneViewportTransformGizmo&&) noexcept;

    void Refresh(
        EditorSceneRuntime& sceneRuntime,
        const ::XCEngine::UI::UIRect& viewportRect,
        const ::XCEngine::UI::UIPoint& pointerScreen,
        bool hoverEnabled);
    bool TryBeginDrag(EditorSceneRuntime& sceneRuntime);
    bool UpdateDrag(EditorSceneRuntime& sceneRuntime);
    bool EndDrag(EditorSceneRuntime& sceneRuntime);
    void CancelDrag(EditorSceneRuntime& sceneRuntime);
    void ResetVisualState();

    bool IsActive() const;
    bool IsHoveringHandle() const;
    const SceneViewportTransformGizmoFrame& GetFrame() const;

private:
    struct State;

    std::unique_ptr<State> m_state = {};
};

void AppendSceneViewportTransformGizmo(
    ::XCEngine::UI::UIDrawList& drawList,
    const SceneViewportTransformGizmoFrame& frame);

} // namespace XCEngine::UI::Editor::App