#include <Wire.h> 
#include <stdio.h>
#include <stdlib.h>
#include <Servo.h> 

int led = 9;
int buzzer = 7;     
int temprature = A0; 
int trigPin = 6;
int echoPin = 5;
int servoPin = 11;

int counter = 0;

const float minPh = 4.0;
boolean phFlag = false;

int brightness = 0; 

Servo servo;
char degree = 176;
const float BETA = 3950; 
int tempCounter = 0;
boolean tempFlag = false;
float cels;
int pos = 0;


boolean waterLevelFlag = false;

extern "C" {
  void chip_init();
  void phController(void *chip_data);
}

void setup(){ 
  pinMode(led, OUTPUT);
  pinMode(buzzer, OUTPUT);
  pinMode(temprature, INPUT);
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  servo.attach(servoPin);

  Serial.begin(9600);

} 

void light(){
  
  if(counter < 21600)
    brightness = 255;

  else if (counter < 64800)
    brightness = 0;

  else
    brightness = 128;

  digitalWrite(led, brightness);  

}



void heater(int tempCounter){
  servo.write(180);
  if (tempCounter == (counter -3)){
    cels += 0.5;  
    Serial.print("in heater Temperature: ");
    Serial.print(cels);
    Serial.println(degree);
    tempFlag = false;
    if (cels > 24){
      servo.write(0);
      Serial.println("Heater is Off now"); 
      delay(5000);
    }
  }
}

void temp() {
  int analogValue = analogRead(A0);
  if (tempFlag == false) 
    cels = 1 / (log(1 / (1023. / analogValue - 1)) / BETA + 1.0 / 298.15) - 273.15;
  // cels ++;
  Serial.print("Temperature: ");
  Serial.print(cels);
  Serial.println(degree);

  if(cels < 24){
    heater(tempCounter);
    if (!tempFlag)
    	tempCounter = counter;
    Serial.println("Heater is ON now"); 
    tempFlag = true;
  }
  else{
    tempFlag = false;
    Serial.println("Heater is Off now"); 
    servo.write(0);
  }
}

int readPh() {
  float pH = analogRead(A1);
	return (int) pH;
}

void phController() {
  phFlag = false;
  int ph = readPh();
  Serial.print("PH : ");
  Serial.println(ph, 1);
  if (ph < minPh) {
    phFlag = true;
    Serial.println("The water is polluted. Turn on the aquarium purifier");
  }
}

void waterLevel(){
  waterLevelFlag = false; 
  long duration, distance;
  digitalWrite(trigPin, LOW); 
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  duration = pulseIn(echoPin, HIGH);
  distance = (duration/2) / 29.1;
  Serial.print("Water Level is : ");  
  Serial.println(distance);   

  if (distance <= 240) {
    waterLevelFlag = true; 
    Serial.println("The aquarium water level is too low, take care of it as soon as possible");   
  }
}

void loop(){
  if (counter >= 172800)
    counter = 0;

  light();
  
  temp();

  if(counter % 3600 == 0)  
    waterLevel();

  if(counter % 1200 == 0)  
    phController();
  
  if(tempFlag == true && phFlag == true && waterLevelFlag == true){
    tone(7, 220, 100);
    Serial.println("The aquarium is in a bad condition");
  }
    
  counter++;
  delay(500);
   
}