HABEMOS GUI

//#include <LiquidCrystal.h>
#include <iostream>

// select the pins used on the LCD panel
/*
LiquidCrystal lcd(8, 9, 4, 5, 6, 7);

// define some values used by the panel and buttons
int lcd_key     = 0;
int adc_key_in  = 0;
*/
const int btnRIGHT = 0;
const int btnUP = 1;
const int btnDOWN = 2;
const int btnLEFT = 3;
const int btnSELECT = 4;
const int btnNONE = 5;

using namespace std;

class Noh;
void context_menu(Noh* option);

class MenuOption{
private:

public:
    char name[16]; // favor não usar o último caractere
    bool leads_to_another_menu;
    Noh* data;
    void select();
    MenuOption(){};
    MenuOption(char* new_name){
        int i = 0;
        for (int i = 0; i < 15; i++){
            name[i] = new_name[i];
        }
        name[16] = '\0';
    };
    ~MenuOption(){};
};

void MenuOption::select(){
    if (this->leads_to_another_menu){
        context_menu(data);
    }
}

class Noh
{
private:
    void* data; // o ponteiro do tipo void pode ser usado pra qualquer propósito
public:
    Noh* next;
    Noh* previous;
    MenuOption* asMenu(){return (MenuOption*)(data);}; // retorna data como um ponteiro para MenuOption
    //Skill* asSkill(){return (Skill*)(data);}; // retorna data como um ponteiro para Skill
    Noh(){
        next = NULL;
        previous = NULL;
        data = NULL;
    };
    Noh(void* new_data){
        data = new_data;
        next = NULL;
        previous = NULL;
    };
    ~Noh(){
        // remove ponteiros que apontam pra este objeto
        if (this->next->previous == this){
            this->next->previous = NULL;
        }
        if (this->previous->next == this){
            this->previous->next = NULL;
        }

        delete (Noh*)(data);
    };

};


int read_LCD_buttons()
{/*
    adc_key_in = analogRead(0);      // read the value from the sensor
    if (adc_key_in > 1000) return btnNONE; // We make this the 1st option for speed reasons since it will be the most likely result
    // For V1.1 us this threshold
    if (adc_key_in < 50)   return btnRIGHT;
    if (adc_key_in < 250)  return btnUP;
    if (adc_key_in < 450)  return btnDOWN;
    if (adc_key_in < 650)  return btnLEFT;
    if (adc_key_in < 850)  return btnSELECT;
    // For V1.0 comment the other threshold and use the one below:
/*
    if (adc_key_in < 50)   return btnRIGHT;
    if (adc_key_in < 195)  return btnUP;
    if (adc_key_in < 380)  return btnDOWN;
    if (adc_key_in < 555)  return btnLEFT;
     if (adc_key_in < 790)  return btnSELECT;
*/
    char choice;
    cin >> choice;
    if (choice == 'u'){
        return btnUP;
    }
    else if (choice == 'd'){
        return btnDOWN;
    }
    else if (choice == 'l'){
        return btnLEFT;
    }
    else if (choice == 'r'){
        return btnRIGHT;
    }
    else if (choice == 's'){
        return btnSELECT;
    }
    return btnNONE;  // when all others fail, return this...
}

void print_menu(Noh* option){

    /*
    lcd.setCursor(0, 0);
    lcd.print(option->asMenu()->name);
    lcd.setCursor(15, 0);
    lcd.print(01111111, BIN); // setinha
    lcd.setCursor(0, 1);
    lcd.print(option->next->asMenu()->name);
    */

    cout << endl << endl << endl << endl << endl << endl << endl << (option->asMenu()->name);
    cout << (char)(0b01111111) << endl; // setinha
    if (option->next != NULL){
        cout << (option->next->asMenu()->name) << endl;
    }
}

void context_menu(Noh* option){
    bool in_context_page = true;
    Noh* last_page = option;
    print_menu(option);
    while (in_context_page){
        switch (read_LCD_buttons()){
            case btnNONE:
                break;
            case btnUP:
                // volta para a opção anterior
                if (option->previous != NULL){
                    option = option->previous;
                }
                print_menu(option);
                break;
            case btnDOWN:
                // vai para a próxima opção
                if (option->next != NULL){
                    option = option->next;
                }
                print_menu(option);
                break;
            case btnLEFT:
                // retorna para a página anterior
                in_context_page = false;
                break;
            default:
                // seleciona a opção atual
                option->asMenu()->select();
                print_menu(option);
        }
    }
}

void add_menu_option(Noh* node_above, Noh* node_to_be_inserted){
    if (node_above->previous == NULL && node_above->next == NULL){ // transforma o menu em uma lista circular
        node_above->previous = node_above;
        node_above->next = node_above;
    }
    node_to_be_inserted->previous = node_above;
    node_to_be_inserted->next = node_above->next;
    node_above->next = node_to_be_inserted;
    node_to_be_inserted->next->previous = node_to_be_inserted;
}

void add_submenu(Noh* node_father, Noh* node_to_be_inserted){
    node_father->asMenu()->leads_to_another_menu = true;
    node_father->asMenu()->data = node_to_be_inserted;
}

int main(){
    Noh* first_page = new Noh((void*)(new MenuOption((char*)"Trains")));
    Noh* aux = new Noh(new MenuOption((char*)"I like them!"));
    add_submenu(first_page, aux);
    Noh* aux2 = new Noh(new MenuOption((char*)"..."));
    add_menu_option(aux, aux2);
    aux2 = new Noh(new MenuOption((char*)"Fuooon"));
    add_menu_option(aux, aux2);
    aux = new Noh(new MenuOption((char*)"Muffin"));
    add_menu_option(first_page, aux);
    aux2 = new Noh(new MenuOption((char*)"I wanna die"));
    add_submenu(aux, aux2);
    aux = new Noh(new MenuOption((char*)":D"));
    add_menu_option(aux2, aux);
    aux = new Noh(new MenuOption((char*)"Stegosaurus"));
    add_menu_option(first_page, aux);
    aux = new Noh(new MenuOption((char*)"Real person"));
    add_menu_option(first_page, aux);
    aux2 = new Noh(new MenuOption((char*)"Skateboards"));
    add_submenu(aux, aux2);
    context_menu(first_page);
    return 0;
}