timely-reference/firmware/Application/Screens/MenuScreen.h

/*
 * Copyright (C) 2019  Max Regan
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

#pragma once


#include <initializer_list>

#include "Bsp/macros.h"

#include "Application/SystemFonts.h"
#include "Application/ScreenManager.h"
#include "Application/Screens/Screen.h"

struct MenuScreenItem {

    enum class Type {
                     NONE,
                     SCREEN,
                     FUNCTION,
                     BACK,
    };

    MenuScreenItem()
        : m_text(nullptr)
        , m_type(Type::NONE)
    {}

    MenuScreenItem(const char *item, Screen &m_screen)
        : m_text(item)
        , m_screen(&m_screen)
        , m_type(Type::SCREEN)
    {}

    MenuScreenItem(const char *item, void (*function)())
        : m_text(item)
        , m_function(function)
        , m_type(Type::FUNCTION)
    {}

    MenuScreenItem(const char *item)
        : m_text(item)
        , m_type(Type::BACK)
    {}

    const char *m_text;
    union {
        Screen *m_screen;
        void (* m_function)();
    };
    Type m_type;
};

class MenuScreen : public Screen {
public:

    static constexpr std::size_t MAX_ITEMS = 5;

    MenuScreen(BSP::DisplayDriver &display,
               ScreenManager &manager,
               const char *title,
               std::initializer_list<MenuScreenItem> items)
        : m_driver(display)
        , m_manager(manager)
        , m_title(title)
        , m_items()
        , m_num_items{0}
        , m_selected{0}
    {
        for (auto &item : items) {
            m_items[m_num_items++] = item;

            // Leave room for "back"
            if (m_num_items == MAX_ITEMS - 1) {
                break;
            }
        }

        new (&m_items[m_num_items++]) MenuScreenItem("Back");
    }

    void render() {
        const struct font &font = default_font;

        //m_driver.clear();

        uint32_t x = 0;
        uint32_t y = 0;
        m_driver.string_at(&x, y, m_title, &font);
        y += font.height + 1;

        m_driver.draw_hline(0, y++, m_driver.get_width());
        m_driver.draw_hline(0, y++, m_driver.get_width());


        for (std::size_t i = 0; i < m_num_items; i++) {
            const char *spacer = " ";
            if (i == m_selected) {
                spacer = ">";
            }
            x = 0;
            m_driver.string_at(&x, y, spacer, &font);
            m_driver.string_at(&x, y, m_items[i].m_text, &font);
            y += font.height;
        }
        m_driver.refresh();
    }

    BSP::ReturnCode init() {
        return BSP::ReturnCode::OK;
    }

    BSP::Schedule::NextTime execute() override {
        return BSP::Schedule::NextTime::never();
    }

    void enable() override {
        m_selected = 0;
        m_driver.clear();
        render();
    }

    void disable() override {
    }

    void notify_up_button() override {
        if (m_selected == 0) {
            m_selected = m_num_items - 1;
        } else {
            m_selected--;
        }

        render();
    }

    void notify_middle_button() override {
        MenuScreenItem &item = m_items[m_selected];
        if (item.m_type == MenuScreenItem::Type::SCREEN) {
            m_manager.push_screen(*item.m_screen);
        } else if (item.m_type == MenuScreenItem::Type::FUNCTION) {
            item.m_function();
            m_manager.pop_screen();
        } else if (item.m_type == MenuScreenItem::Type::BACK) {
            m_manager.pop_screen();
        }
    }

    void notify_down_button() override {
        if (m_selected == m_num_items - 1) {
            m_selected = 0;
        } else {
            m_selected++;
        }

        render();
    }

private:

    BSP::DisplayDriver &m_driver;
    ScreenManager &m_manager;
    const char *m_title;
    MenuScreenItem m_items[MAX_ITEMS];
    std::size_t m_num_items;
    std::size_t m_selected;
};