#ifndef XTC_GRAPH_WIDGET_HPP
#define XTC_GRAPH_WIDGET_HPP
#include <FL/Fl_Widget.H>
#include <array>
#include "xtc/xtc_engine.h"

class Fl_Box;

/* GUI positions/selection only. Domain snapshots and edits stay in the C API. */
class GraphWidget : public Fl_Widget {
  public:
    using EditHandler = xtc_result (*)(void *, const xtc_graph_edit &, size_t *);
    GraphWidget(int x, int y, int width, int height, const xtc_graph *graph, EditHandler handler, void *context,
                Fl_Box *feedback);

    void reset_layout()
    {
        count_ = 0;
        selected_node_ = SIZE_MAX;
        edge_selected_ = dragging_ = wiring_ = false;
    }

    void set_graph(const xtc_graph *graph);

    const xtc_graph *graph() const
    {
        return graph_;
    } // Borrowed, GUI thread only.

    xtc_result add_node(xtc_node_type type);
    xtc_result connect_ports(const xtc_connection_info &connection);
    xtc_result delete_selected();
    bool select_node(size_t id);
    bool select_connection(size_t source, size_t destination);
    bool move_node(size_t id, int left, int top);
    bool node_position(size_t id, int &left, int &top) const;
    int handle(int event) override;

  protected:
    void draw() override;

  private:
    struct Position {
        size_t id = SIZE_MAX;
        int left = 0, top = 0;
    };

    std::array<Position, 256> positions_{};
    size_t count_ = 0U;
    const xtc_graph *graph_;
    EditHandler handler_;
    void *context_;
    Fl_Box *feedback_;
    size_t selected_node_ = SIZE_MAX;
    xtc_connection_info selected_edge_{};
    bool edge_selected_ = false;
    bool dragging_ = false, wiring_ = false;
    size_t wire_node_ = SIZE_MAX, wire_port_ = 0U;
    int drag_x_ = 0, drag_y_ = 0, mouse_x_ = 0, mouse_y_ = 0;
    void feedback(xtc_result result, const char *success);
    bool hit_port(int left, int top, size_t &node, size_t &port) const;
    bool port_position(size_t id, size_t port, int &left, int &top) const;
};
#endif