#include <avr/sleep.h>
#include <avr/power.h>
#include <avr/interrupt.h>
#include <OneWire.h>
#include <DallasTemperature.h>

const int pinAnalogique = A0;
const int ledPin = 2;

// DS18B20
#define ONE_WIRE_BUS 3
OneWire oneWire(ONE_WIRE_BUS);
DallasTemperature sensors(&oneWire);

// Pont diviseur
const float R1 = 22000.0;
const float R2 = 6800.0;
float correction = 1.000;

// Flag réveil
volatile bool wakeUpFlag = false;

// Interruption sur RX (PCINT16)
ISR(PCINT2_vect) {
  wakeUpFlag = true;
}

void setup() {
  Serial.begin(9600);
  sensors.begin();
Serial.println("-------------------------------------------");
Serial.println(" ** Capteur T° et V par F8ASB ** V1.00");
Serial.println(" T= valeur temperature et V=valeur tension ");
Serial.println("-------------------------------------------");
  pinMode(ledPin, OUTPUT);
  digitalWrite(ledPin, LOW);

  // Active l’interruption sur RX (D0)
  PCICR |= (1 << PCIE2);      // Active PCINT[23:16]
  PCMSK2 |= (1 << PCINT16);   // Active PCINT16 = RX
}

void enterSleep() {
  wakeUpFlag = false;

  set_sleep_mode(SLEEP_MODE_PWR_DOWN);
  sleep_enable();
  noInterrupts();
  EIFR = bit(PCIF2);  // Efface flags
  interrupts();
  sleep_cpu();        // Dodo profond

  sleep_disable();    // Réveil ici
}

void loop() {

  // Dodo tant qu’aucune activité série
  if (!wakeUpFlag) {
    enterSleep();
  }

  // Réveil → lecture série
  if (Serial.available()) {
    digitalWrite(ledPin, HIGH);
    char c = Serial.read();

    // --- TENSION ---
    if (c == 'V') {
      int brut = analogRead(pinAnalogique);
      float vA0 = brut * (5.0 / 1023.0);
      float vIn = vA0 * ((R1 + R2) / R2) * correction;

      Serial.print("V=");
      Serial.print(vIn);
      Serial.println(" V");
    }

    // --- TEMPERATURE ---
    if (c == 'T') {
      sensors.requestTemperatures();
      float tempC = sensors.getTempCByIndex(0);

      Serial.print("T=");
      Serial.print(tempC);
      Serial.println(" C");
    }

    digitalWrite(ledPin, LOW);
  }
}