#include <Arduino.h>
#include <Bounce2.h>
#include <Wire.h>
#include <U8g2lib.h>

U8G2_SSD1306_128X64_NONAME_F_HW_I2C u8g2(U8G2_R0, /* reset=*/ U8X8_PIN_NONE);

// Pins
const int PIN_BTN_PLAY = 2;
const int PIN_BTN_NEXT = 3;
const int PIN_BTN_PREV = 4;
const int PIN_BTN_MENU = 5;
const int PIN_BTN_SCREEN = 6;
const int PIN_SLIDER = A0; 

// Bounce objects
Bounce btnPlay = Bounce();
Bounce btnNext = Bounce();
Bounce btnPrev = Bounce();
Bounce btnMenu = Bounce();
Bounce btnScreen = Bounce();

const char* ultimoTasto = "In attesa...";
int ultimoVolume = -1; 

// NEW: Variable to track if the screen is on or off
bool isScreenOn = true; 

void setup() {
  Serial.begin(9600);
  u8g2.begin();

  btnPlay.attach(PIN_BTN_PLAY, INPUT_PULLUP);
  btnPlay.interval(10);
  btnNext.attach(PIN_BTN_NEXT, INPUT_PULLUP);
  btnNext.interval(10);
  btnPrev.attach(PIN_BTN_PREV, INPUT_PULLUP);
  btnPrev.interval(10);
  btnMenu.attach(PIN_BTN_MENU, INPUT_PULLUP);
  btnMenu.interval(10);
  btnScreen.attach(PIN_BTN_SCREEN, INPUT_PULLUP);
  btnScreen.interval(10);

  aggiornaSchermo(0); 
}

void loop() {
  btnPlay.update();
  btnNext.update();
  btnPrev.update();
  btnMenu.update();
  btnScreen.update();

  bool bisognaAggiornare = false;

  // --- STANDARD BUTTONS ---
  if (btnPlay.fell()) { ultimoTasto = "PLAY / PAUSE"; bisognaAggiornare = true; }
  if (btnNext.fell()) { ultimoTasto = "NEXT TRACK"; bisognaAggiornare = true; }
  if (btnPrev.fell()) { ultimoTasto = "PREV TRACK"; bisognaAggiornare = true; }
  if (btnMenu.fell()) { ultimoTasto = "MENU"; bisognaAggiornare = true; }
  
  // --- NEW: TOGGLE SCREEN BUTTON ---
  if (btnScreen.fell()) { 
    isScreenOn = !isScreenOn; // Flip the boolean (True becomes False, False becomes True)
    
    if (isScreenOn) {
      u8g2.setPowerSave(0); // 0 = Wake up
      ultimoTasto = "SCREEN WOKE UP";
    } else {
      u8g2.setPowerSave(1); // 1 = Go to sleep
      ultimoTasto = "GOING TO SLEEP";
    }
    bisognaAggiornare = true; 
  }

  // --- VOLUME SLIDER ---
  int valoreGrezzo = analogRead(PIN_SLIDER);
  int volumePercent = map(valoreGrezzo, 0, 1023, 0, 100);

  if (volumePercent != ultimoVolume) {
    ultimoVolume = volumePercent;
    bisognaAggiornare = true;
  }

  // --- UPDATE OLED ---
  // We only bother drawing the new graphics if the screen is actually ON
  if (bisognaAggiornare && isScreenOn) {
    aggiornaSchermo(ultimoVolume);
  }
}

void aggiornaSchermo(int volume) {
  u8g2.clearBuffer();
  
  u8g2.setFont(u8g2_font_ncenB08_tr);  
  u8g2.drawStr(0, 15, "Hai premuto:"); 
  u8g2.setFont(u8g2_font_ncenB12_tr);  
  u8g2.drawStr(0, 35, ultimoTasto);    
  
  u8g2.drawFrame(0, 50, 128, 10); 
  
  int larghezzaBarra = map(volume, 0, 100, 0, 128); 
  u8g2.drawBox(0, 50, larghezzaBarra, 10);
  
  u8g2.sendBuffer(); 
}