selection_widget.hpp

// Copyright Take Vos 2020-2021.
// Distributed under the Boost Software License, Version 1.0.
// (See accompanying file LICENSE_1_0.txt or copy at https://www.boost.org/LICENSE_1_0.txt)
 
#pragma once
 
#include "widget.hpp"
#include "label_widget.hpp"
#include "overlay_widget.hpp"
#include "scroll_widget.hpp"
#include "row_column_widget.hpp"
#include "menu_button_widget.hpp"
#include "selection_delegate.hpp"
#include "default_selection_delegate.hpp"
#include "../observable.hpp"
#include "../weak_or_unique_ptr.hpp"
#include <memory>
#include <string>
#include <array>
#include <optional>
#include <future>
 
namespace tt {
 
class selection_widget final : public widget {
public:
    using super = widget;
    using delegate_type = selection_delegate;
 
    observable<label> unknown_label;
 
    selection_widget(gui_window &window, widget *parent, std::weak_ptr<delegate_type> delegate) noexcept;
 
    template<typename OptionList, typename Value, typename... Args>
    selection_widget(gui_window &window, widget *parent, OptionList &&option_list, Value &&value, Args &&...args) noexcept
        requires(not std::is_convertible_v<Value, weak_or_unique_ptr<delegate_type>>) :
        selection_widget(
            window,
            parent,
            make_unique_default_selection_delegate(
                std::forward<OptionList>(option_list),
                std::forward<Value>(value),
                std::forward<Args>(args)...))
    {
    }
 
    void init() noexcept override;
    void deinit() noexcept override;
    [[nodiscard]] bool constrain(utc_nanoseconds display_time_point, bool need_reconstrain) noexcept override;
    [[nodiscard]] void layout(utc_nanoseconds display_time_point, bool need_layout) noexcept override;
    void draw(draw_context context, utc_nanoseconds display_time_point) noexcept override;
    bool handle_event(mouse_event const &event) noexcept override;
    bool handle_event(command command) noexcept override;
    [[nodiscard]] hitbox hitbox_test(point2 position) const noexcept override;
    [[nodiscard]] bool accepts_keyboard_focus(keyboard_focus_group group) const noexcept override;
    [[nodiscard]] color focus_color() const noexcept override;
private:
    weak_or_unique_ptr<delegate_type> _delegate;
 
    typename delegate_type::callback_ptr_type _delegate_callback;
    typename decltype(unknown_label)::callback_ptr_type _unknown_label_callback;
 
    label_widget *_current_label_widget = nullptr;
    label_widget *_unknown_label_widget = nullptr;
 
    aarectangle _option_rectangle;
    aarectangle _left_box_rectangle;
 
    font_glyph_ids _chevrons_glyph;
    aarectangle _chevrons_rectangle;
 
    bool _selecting = false;
    bool _has_options = false;
 
    overlay_widget *_overlay_widget = nullptr;
    vertical_scroll_widget<> *_scroll_widget = nullptr;
    column_widget *_column_widget = nullptr;
 
    std::vector<menu_button_widget *> _menu_button_widgets;
    std::vector<typename menu_button_widget::callback_ptr_type> _menu_button_callbacks;
 
    selection_widget(gui_window &window, widget *parent, weak_or_unique_ptr<delegate_type> delegate) noexcept;
    [[nodiscard]] menu_button_widget const *get_first_menu_button() const noexcept;
    [[nodiscard]] menu_button_widget const *get_selected_menu_button() const noexcept;
    void start_selecting() noexcept;
    void stop_selecting() noexcept;
    void repopulate_options() noexcept;
    void draw_outline(draw_context context) noexcept;
    void draw_left_box(draw_context context) noexcept;
    void draw_chevrons(draw_context context) noexcept;
};
 
} // namespace tt