#include <Wire.h>
#include <RTClib.h>
#include <LiquidCrystal_I2C.h>

RTC_DS1307 rtc;
LiquidCrystal_I2C lcd(0x27, 20, 4); // Vérifie l'adresse si écran vide

const int buttonUp = 4;
const int buttonDown = 7;
const int buttonOK = 8;
const int ledPin = 13;

int timerSeconds = 10; // valeur initiale
bool timerRunning = false;
unsigned long timerStart = 0;
unsigned long timerDuration = 0;

void setup() {
  //Serial.begin(9600);
  Wire.begin();
  rtc.begin();
  lcd.init();
  lcd.backlight();

  if (!rtc.isrunning()) {
    rtc.adjust(DateTime(F(__DATE__), F(__TIME__)));
  }

  pinMode(ledPin, OUTPUT);
  pinMode(buttonUp, INPUT_PULLUP);
  pinMode(buttonDown, INPUT_PULLUP);
  pinMode(buttonOK, INPUT_PULLUP);

  lcd.setCursor(0, 0);
  lcd.print("Regler minuterie:");
}

void loop() {
  DateTime now = rtc.now();

  // Afficher heure en temps réel
  lcd.setCursor(0, 1);
  lcd.print("Heure: ");
  printTimeLCD(now);

  if (!timerRunning) {
    handleButtons();

    lcd.setCursor(0, 2);
    lcd.print("Duree: ");
    lcd.print(timerSeconds);
    lcd.print("s      ");
  }

  if (timerRunning) {
    unsigned long elapsed = millis() - timerStart;
    long remaining = (timerDuration - elapsed) / 1000;

    if (remaining < 0) remaining = 0;

    lcd.setCursor(0, 3);
    lcd.print("Reste: ");
    lcd.print(remaining);
    lcd.print("s     ");

    if (elapsed >= timerDuration) {
      digitalWrite(ledPin, LOW);
      timerRunning = false;
      lcd.setCursor(0, 2);
      lcd.print("Minuterie terminee ");
    }
  }

  delay(200); // évite le rebond + clignotements
}

void handleButtons() {
  static unsigned long lastPress = 0;
  if (millis() - lastPress < 200) return; // debounce

  if (digitalRead(buttonUp) == LOW) {
    timerSeconds += 1;
    if (timerSeconds > 600) timerSeconds = 600; // max 10 min
    lastPress = millis();
  }

  if (digitalRead(buttonDown) == LOW) {
    timerSeconds -= 1;
    if (timerSeconds < 1) timerSeconds = 1;
    lastPress = millis();
  }

  if (digitalRead(buttonOK) == LOW) {
    timerDuration = timerSeconds * 1000UL;
    timerStart = millis();
    timerRunning = true;
    digitalWrite(ledPin, HIGH);
    lcd.setCursor(0, 2);
    lcd.print("Minuterie demarree ");
    lastPress = millis();
  }
}

void printTimeLCD(DateTime t) {
  if (t.hour() < 10) lcd.print('0');
  lcd.print(t.hour());
  lcd.print(':');
  if (t.minute() < 10) lcd.print('0');
  lcd.print(t.minute());
  lcd.print(':');
  if (t.second() < 10) lcd.print('0');
  lcd.print(t.second());
}