#include <OneWire.h>
#include <DallasTemperature.h>

const int phPin = A0;   // pH potentiometer (SIG)
const int ecPin = A1;   // EC potentiometer (SIG)
const int tempPin = 2;  // DS18B20 data pin (D2)

const int coolingPin = 4;  // relay/MOSFET controlling cooling system
const int heaterPin  = 5;  // relay/MOSFET controlling heater

OneWire oneWire(tempPin);
DallasTemperature tempSensor(&oneWire);

void setup() {
  Serial.begin(115200);
  delay(1000);

  analogReadResolution(12);   // Force 12-bit ADC (0-4095)
  tempSensor.begin();

  pinMode(coolingPin, OUTPUT);
  pinMode(heaterPin, OUTPUT);
  digitalWrite(coolingPin, LOW);
  digitalWrite(heaterPin, LOW);

  Serial.println("HydroTank - pH + EC + Temp Test");
}

void loop() {
  // --- pH (simulated) ---
  int phRaw = analogRead(phPin);
  float simulatedPH = map(phRaw, 0, 4095, 0, 1400) / 100.0;

  // --- EC (simulated) ---
  int ecRaw = analogRead(ecPin);
  float simulatedEC = map(ecRaw, 0, 4095, 0, 2000) / 100.0;

  // --- Temperature ---
  tempSensor.requestTemperatures();
  float waterTemp = tempSensor.getTempCByIndex(0);

  Serial.print("pH: ");
  Serial.print(simulatedPH, 2);
  Serial.print("  |  EC: ");
  Serial.print(simulatedEC, 2);
  Serial.print("  |  Temp: ");
  Serial.print(waterTemp, 2);
  Serial.println(" C");

  // --- Temperature logic ---
  if (waterTemp > 25.0) {
    Serial.println("ALERT: Water too hot -> cooling ON");
    digitalWrite(coolingPin, HIGH);
    digitalWrite(heaterPin, LOW);
  } else if (waterTemp < 18.0) {
    Serial.println("ALERT: Water too cold -> heater ON");
    digitalWrite(heaterPin, HIGH);
    digitalWrite(coolingPin, LOW);
  } else {
    digitalWrite(coolingPin, LOW);
    digitalWrite(heaterPin, LOW);
  }

  delay(1000);
}