#pragma once
#include "vde/core/aabb.h"
#include "vde/spatial/spatial_index.h"
#include <memory>

namespace vde::spatial {
using core::Point3D;
using core::Vector3D;
using core::Ray3Dd;
using core::Triangle3D;

template <typename T> struct OctreeNode;
template <typename T> struct OctreeData;

template <typename T>
class Octree : public SpatialIndex<T> {
public:
    explicit Octree(int max_depth = 8, int max_items = 16);
    void build(const std::vector<T>& items) override;
    void insert(const T& item) override;
    bool remove(const T& item) override;
    std::vector<T> query_range(const AABB3D& range) const override;
    std::vector<T> query_knn(const Point3D& point, size_t k) const override;
    std::vector<T> query_ray(const Ray3Dd& ray) const override;
    void clear() override;
    size_t size() const override;

private:
    void insert_recursive(int node_idx, const T& item, int depth);
    void subdivide_recursive(int node_idx, int depth);
    void query_range_recursive(int node_idx, const AABB3D& range,
                               std::vector<T>& result) const;
    void query_ray_recursive(int node_idx, const Ray3Dd& ray,
                             std::vector<T>& result) const;

    /// Item position helper (for non-Point3D types)
    static Point3D get_position(const T& item);

    std::shared_ptr<OctreeData<T>> data_;
    int max_depth_, max_items_;
};

}  // namespace vde::spatial