prism/engine/core/include/imgui_backend.hpp

#pragma once

#include <filesystem>
#include <functional>
#include <string_view>

#include "platform.hpp"

namespace prism {
    class imgui_backend {
    public:
        imgui_backend();

        void begin_frame(float delta_time);

        void render();

        void process_move(platform::window_ptr identifier);
        void process_resize(platform::window_ptr identifier);

        void process_mouse_down(int button);

        void process_key_down(unsigned int key_code);
        void process_key_up(unsigned int key_code);

        void process_text_input(std::string_view string);

        /**Opens a file dialog to select a file. This will not block.
         @param existing Whether or not to limit to existing files.
         @param returnFunction The callback function when a file is selected or the dialog is cancelled. An empy string
         is returned when cancelled.
         @param openDirectory Whether or not to allow selecting directories as well.
         */
        void open_dialog(bool existing, std::function<void(std::string)> returnFunction, bool openDirectory = false);

        /**Opens a file dialog to select a save location for a file. This will not block.
         @param returnFunction The callback function when a file is selected or the dialog is cancelled. An empy string
         is returned when cancelled.
         */
        void save_dialog(std::function<void(std::string)> returnFunction);

    private:
        bool mouse_buttons[3] = {};

        bool open_dialog_next_frame = false;
        bool save_dialog_next_frame = false;

        struct dialog_data {
            std::filesystem::path current_path;
            std::filesystem::path selected_path;
            std::function<void(std::string)> return_function;
            bool select_directory = false;
        };

        dialog_data open_dialog_data;
        dialog_data save_dialog_data;
    };
} // namespace prism