// Include necessary libraries
#include <NewPing.h>
#include <OneWire.h>
#include <DallasTemperature.h>

// Define constants
const int TRIGGER_PIN = 2;         
// Ultrasonic sensor trigger pin
const int ECHO_PIN = 3;            
// Ultrasonic sensor echo pin
const int SOLENOID_PIN = 4;        
// Solenoid valve control pin
const int HEATER_PIN = 5;          
// Heater control pin
const int MIN_LEVEL = 5;           
// Minimum water level in liters
const int MAX_LEVEL = 15;         
 // Maximum water level in liters
const int MAX_TEMPERATURE = 39;    
// Maximum temperature in degrees Celsius

// Create instances of the libraries
NewPing sonar(TRIGGER_PIN, ECHO_PIN);
OneWire oneWire(6);                  
// Temperature sensor on pin 6
DallasTemperature temperatureSensor(&oneWire);

void setup() {
  pinMode(SOLENOID_PIN, OUTPUT);
  digitalWrite(SOLENOID_PIN, HIGH);  
// Close the solenoid valve initially
  pinMode(HEATER_PIN, OUTPUT);
  digitalWrite(HEATER_PIN, LOW);     
// Turn off the heater initially
  Serial.begin(9600);
temperatureSensor.begin();
}

void loop() {
  delay(500);  // Add a small delay between readings for stability
  
  // Get distance from the ultrasonic sensor in centimeters
  unsigned int distance = sonar.ping_cm();
  
  // Calculate water level in liters based on the distance
  float waterLevel = calculateWaterLevel(distance);
  
  // Read temperature from the sensor in degrees Celsius
  temperatureSensor.requestTemperatures();
  float temperature = temperatureSensor.getTempCByIndex(0);
  
  Serial.print("Water Level: ");
  Serial.print(waterLevel);
  Serial.print(" liters   Temperature: ");
  Serial.print(temperature);
  Serial.println(" °C");
  
  // Check water level and temperature to make decisions
  if (waterLevel <= MIN_LEVEL) {
digitalWrite(SOLENOID_PIN, LOW);  
// Open solenoid valve
  }
  
  if (waterLevel >= MAX_LEVEL) {
digitalWrite(SOLENOID_PIN, HIGH);  
// Close solenoid valve
  }
  
  if (waterLevel >= MIN_LEVEL && temperature < MAX_TEMPERATURE) {
digitalWrite(HEATER_PIN, HIGH);  
// Turn on heater
  } else {
digitalWrite(HEATER_PIN, LOW);   
// Turn off heater
  }
}

// Function to calculate water level based on distance
float calculateWaterLevel(unsigned int distance) {
  // Your formula to convert distance to water level in liters
  // Adjust this formula based on the characteristics of your tank and sensor
  // For example: waterLevel = maxLevel - (maxLevel - minLevel) * (distance / maxDistance)
  return distance; 
 // Replace with the actual formula
}