// Define constants
#define menuButton 2
#define menuSelect 3
#define menuSave 4
#define debounceTimeout 50

int menuButtonPreviousState = LOW;
int menuSelectPreviousState = LOW;
int menuSavePreviousState = LOW;

// Define variables
long int lastDebounceTime;
bool lightSensor = true;
bool tempSensor = true;

char * menuOptions[] = {"Check Temp", "Check Light"};
bool featureSetting[] = {false,false};

bool menuMode = false;
bool menuNeedsPrint = false;
int optionSelected = 0;

void setup()
{
	pinMode(menuButton, INPUT);
  	Serial.begin(9600);
}

// Function to return the current selected option
char *ReturnOptionSelected(){
  	char *menuOption = menuOptions[optionSelected];
  	
  	// Return optionSelected
  	return menuOption;
}

// Function to return status of current selected option
char *ReturnOptionStatus(){
  	bool optionSetting = featureSetting[optionSelected];
  char *optionSettingVal;
  if (optionSetting == false){
    optionSettingVal = "False";
  }else{
    optionSettingVal = "True";
  }
  	
  	// Return optionSetting
  	return optionSettingVal;
}

// Function to toggle current option
bool ToggleOptionSelected(){
  	featureSetting[optionSelected] = !featureSetting[optionSelected];
  return true;
}

// The main loop
void loop()
{
  	// Read the buttons
	int menuButtonPressed = digitalRead(menuButton);
  	int menuSelectPressed = digitalRead(menuSelect);
  	int menuSavePressed = digitalRead(menuSave);
  
  	// Get the current time
  	long int currentTime = millis();
  
  if(menuButtonPressed == LOW && menuSelectPressed == LOW && menuSavePressed == LOW){
    //Reset the count time while button is not pressed
    lastDebounceTime = currentTime;
	menuButtonPreviousState = LOW;
	menuSelectPreviousState = LOW;
    menuSavePreviousState = LOW;
  }
  
  if(((currentTime - lastDebounceTime) > debounceTimeout)){
    // If the timeout is reached, button pressed!
    
    // menuButton is pressed, provide logic
    // Only fires when the button has previously been released
    if((menuButtonPressed == HIGH) && (menuButtonPreviousState == LOW)){
      
      if(menuMode == false){
        menuMode = true;
        // Let the user know
        Serial.println("Menu is active");
        
      }else if (menuMode == true && optionSelected < 1){
        // Change option if menu is active
        optionSelected = optionSelected + 1;
        
      }else if (menuMode == true && optionSelected >= 1){
        // Reset option
        optionSelected = 0;
        
      }
      
      	// Print the menu
      	menuNeedsPrint = true;
      	// Toggle the button prev. state to only display menu 
      	// if the button is released and pressed again
      	menuButtonPreviousState = menuButtonPressed; // Would be HIGH
    }
    
    // menuSelect is pressed, provide logic
    if((menuSelectPressed == HIGH) && (menuSelectPreviousState == LOW)){
      
      if(menuMode){
        
        // Print the menu!
        menuNeedsPrint = true;
        // Change the selected option
        // At the moment, this is just true/false 
        // but could be anything
        bool toggle = ToggleOptionSelected();
        if(toggle){
          menuNeedsPrint = true;
        }else{
          Serial.print("Something went wrong. Please try again");
        }
      }
      // Toggle state to only toggle if released and pressed again
      menuSelectPreviousState = menuSelectPressed;
    }
    
    if((menuSavePressed == HIGH) && (menuSavePreviousState == LOW)){
      
      // Exit the menu
      // Here you could do any tidying up
      // or save to EEPROM
      menuMode = false;
      Serial.println("Menu exited");
      
      // Toggle state so menu only exits once
      menuSavePreviousState = menuSavePressed;
    }
  }
  
  // Print the current menu option active, but only print it once
  if(menuMode && menuNeedsPrint){
    	
      // We have printed the menu, so unless something 
      // happens, no need to print it again
      menuNeedsPrint = false;

      char *optionActive = ReturnOptionSelected();
      char *optionStatus = ReturnOptionStatus();

      Serial.print("Selected: ");
      Serial.print(optionActive);
      Serial.print(": ");
      Serial.print(optionStatus);
      Serial.println();
  }
  
}