// Include the libraries we need
#include <OneWire.h>
#include <DallasTemperature.h>
#include <Wire.h>
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x3F, 16, 2);

#define VOLTAGE 5.00    //system voltage
#define OFFSET -260      //zero drift voltage
#define LED 13         //operating instructions
#define ONE_WIRE_BUS 12 //Temp Sensor datawire connected to arduino pin equivalent 12
#define T2 11

double orpValue;

#define ArrayLenth  40    //times of collection
#define orpPin 1          //orp meter output,connect to Arduino controller ADC pin

// Setup a oneWire instance to communicate with any OneWire devices (not just Maxim/Dallas temperature ICs)
OneWire oneWire(ONE_WIRE_BUS);
OneWire myWire(T2);
// Pass our oneWire reference to Dallas Temperature. 
DallasTemperature sensors(&oneWire);
DallasTemperature sensores(&myWire);
int orpArray[ArrayLenth];
int orpArrayIndex=0;
int in1 = 7;
int DoseT = 6;
int Dosemv = 5;
float factor = 0;
float agua = 0;
const int Trigger = 9;   //Pin digital 9 para el Trigger del sensor
const int Echo = 10;   //Pin digital 10 para el Echo del sensor

double avergearray(int* arr, int number){
  int i;
  int max,min;
  double avg;
  long amount=0;
  if(number<=0){
    printf("Error number for the array to avraging!/n");
    return 0;
  }
  if(number<5){   //less than 5, calculated directly statistics
    for(i=0;i<number;i++){
      amount+=arr[i];
    }
    avg = amount/number;
    return avg;
  }else{
    if(arr[0]<arr[1]){
      min = arr[0];max=arr[1];
    }
    else{
      min=arr[1];max=arr[0];
    }
    for(i=2;i<number;i++){
      if(arr[i]<min){
        amount+=min;        //arr<min
        min=arr[i];
      }else {
        if(arr[i]>max){
          amount+=max;    //arr>max
          max=arr[i];
        }else{
          amount+=arr[i]; //min<=arr<=max
        }
      }//if
    }//for
    avg = (double)amount/(number-2);
  }//if
  return avg;
}

// the setup function runs once when you press reset or power the board
void setup() {
  // initialize digital pin LED_BUILTIN as an output.
  Wire.begin();
  Serial.begin(9600);
  lcd.init();           // initialize the lcd 
  sensors.begin();    // Start up the temp sensor library
  sensores.begin();
  pinMode(LED,OUTPUT);   // Set inbuilt LED to output
  pinMode(DoseT, OUTPUT);
  pinMode(Dosemv, OUTPUT);
  // Print a message to the LCD.
  lcd.backlight();
  lcd.setCursor(0,0);
  //Set Relay pins to output and turn them on
  pinMode(in1, OUTPUT);
  digitalWrite(in1, LOW);
  pinMode(Trigger, OUTPUT); //pin como salida
  pinMode(Echo, INPUT);  //pin como entrada
  digitalWrite(Trigger, LOW);//Inicializamos el pin con 0
}
// the loop function runs over and over again forever
void loop() {
  float t; //timepo que demora en llegar el eco
  float d; //distancia en centimetros

  digitalWrite(Trigger, HIGH);
  delayMicroseconds(10);          //Enviamos un pulso de 10us
  digitalWrite(Trigger, LOW);
  
  t = pulseIn(Echo, HIGH); //obtenemos el ancho del pulso
  d = t/59;             //escalamos el tiempo a una distancia en cm
  static unsigned long orpTimer=millis();   //analog sampling interval
  static unsigned long printTime=millis();
  if(millis() >= orpTimer)
  {
    orpTimer=millis()+20;
    orpArray[orpArrayIndex++]=analogRead(orpPin);    //read an analog value every 20ms
    if (orpArrayIndex==ArrayLenth) {
      orpArrayIndex=0;
    }   
    orpValue=((30*(double)VOLTAGE*1000)-(75*avergearray(orpArray, ArrayLenth)*VOLTAGE*1000/1024))/75-OFFSET;   //convert the analog value to orp according the circuit
  }
  if(millis() >= printTime)   //Every 800 milliseconds, print a numerical, convert the state of the LED indicator
  {
	printTime=millis()+800;
        digitalWrite(LED,1-digitalRead(LED));
  }
  sensors.requestTemperatures();
  sensores.requestTemperatures();
  agua = (2.04-(d-4)*0.2);
  lcd.clear(); 
  lcd.setCursor(0, 0);
  lcd.print("ORP:");
  lcd.print((int)orpValue);
  lcd.print("mV");
  lcd.print(" ");
  lcd.print(agua);
  lcd.print("L");
  lcd.setCursor(0,1);
  lcd.print("T1:");
  lcd.print(sensors.getTempCByIndex(0));
  lcd.print("T2:");
  lcd.print(sensores.getTempCByIndex(0));
  factor = 25;
/*  if (factor <= 0){
    factor = 25;}
  else {
    factor = factor;}*/
  if(sensores.getTempCByIndex(0) < factor)  {
  digitalWrite(in1, HIGH);}
  else {
  digitalWrite(in1, LOW);}
  if((agua < 1.9) && (sensors.getTempCByIndex(0) < 25)){
   digitalWrite(DoseT, HIGH);}
  else {
   digitalWrite(DoseT, LOW);}
  if((agua < 1.9) && ((int)orpValue < 300)){
   digitalWrite(Dosemv, HIGH);}
  else {
   digitalWrite(Dosemv, LOW);}
  delay(300);
  }