/* ritten by Jonathan Lee Paul. Updated Wednesday, 7/18/18 */

#include <Wire.h>
#include <LiquidCrystal_I2C.h>

#include <dht.h>
#define DHT_PIN 8 // Defines the DHT Data pin

/*CO2 Definitions START*/
#define         MG_PIN                       (1)     //define the CO2 analog Pin
#define         DC_GAIN                      (8.5)   //define the DC gain of amplifier

#define         READ_SAMPLE_INTERVAL         (32)    //define how many samples you are going to take in normal operation
#define         READ_SAMPLE_TIMES            (1)     //define the time interval(in milisecond) between each samples in normal operation

#define         V400     (582)                       //測量室外空氣得到的AnalogValue(400ppm)
#define         V40000   (345)                       //測量呼氣得到的AnalogValue(40000ppm)
/*CO2 Definitions END*/

dht DHT; // Creates a DHT object

const int loopDelay = 1000;

int soilval = 0; //value for storing moisture value
int newval = 0;
int soilPin = A0;//Declare a variable for the soil moisture sensor
int soilPower = 7;

int ledPin = 52;

int breakerPin = 23; //This  pin connects to the relay that will momentarily cut power to the usb power hub during setup()
int humidifierPin = 25; //This pin connects to the humidifier-circuit relay's data pin
int fanPin = 27; //This pin connects to the fan-circuit relay's data pin

/*The humidifier will be on if h is between 0% and */
float lowThresh = 75.0; //This is the lower limit of our incubator's humidity threshold. If h is lower than this value, turn on the humidifier
float humidifierStopGap = 82.0; //This is the percentage that the humidifier will try to achieve while on. If h is higher than this value, turn off the humidifier.
float fanStopGap = 83; //this is the percentage that the fan will try to achieve while on. If h is lower than this value, turn the fan off
float highThresh = 85.0; //This is the upper limit of our incubator's humidity threshold. If h is higher than this value, turn on the fan

float slope=(V40000-V400)/(4.602-2.602);
//校正線的斜率計算
//log40000=4.602
//log400=2.602

const float VRefer = 5;      // voltage of O2 adc reference
const int O2Pin   = A14;

LiquidCrystal_I2C lcd(0x3F, 2, 1, 0, 4, 5, 6, 7, 3, POSITIVE);  //confirm LCD I2C configuration


int oldh = 666;
String statush = "off";

void setup() {
  Serial.begin(9600);
  lcd.begin(16, 2);      //initialize a 16x2 lcd matrix

  pinMode(soilPower, OUTPUT);//Set D7 as an OUTPUT
  digitalWrite(soilPower, LOW);

  pinMode(MG_PIN, OUTPUT);

  pinMode(humidifierPin, OUTPUT);
  pinMode(breakerPin, OUTPUT);
  pinMode(ledPin, OUTPUT);
  pinMode(fanPin, OUTPUT);

  /*
  //flash backlight 3 times
  for(int i = 0; i < 3; i++) {
    lcd.backlight();
    delay(150);
    lcd.noBacklight();
    delay(150);
  }
  */

  lcd.clear();
  lcd.backlight();

  //Cut the breaker once
  lcd.setCursor(0,0);lcd.print("Cutting Breaker");
  delay(200);
  digitalWrite(breakerPin, HIGH);
  delay(200);
  digitalWrite(breakerPin, LOW);
  lcd.setCursor(0,1);lcd.print("Done");
  delay(200);
  tone(53,1000,100);


}

void loop() {
  int readData = DHT.read22(DHT_PIN); // Reads the data from the DHT
  float t = DHT.temperature; // Isolates the DHT temp
  int h = DHT.humidity; // Isolates the values of the humidity

  int percentage;
  float analogValue;
  float volts;

  analogValue = MGRead(MG_PIN);
  volts=analogValue*5/1024;
  percentage = MGGetPercentage(analogValue);

  float O2Vout = 0;
  O2Vout = readO2O2Vout();
  float O2Percent = readConcentration();
  //int td = 2;tone(53,1000,td);delay(td);


  /*Toggling the humidifier  based on air humidity input from the DHT22*/
  if (h != oldh){
    if (h < lowThresh && statush == "off"){ //turn on the humidifier. Beep the relay once
      digitalWrite(humidifierPin, HIGH);
      delay(100);
      digitalWrite(humidifierPin, LOW);
      statush = "on";
      tone(53,1000,100);lcd.clear();lcd.setCursor(0,0);lcd.print("HUM TURNING ON");delay(1000);
    }
    if (h > humidifierStopGap && statush == "on"){ //turn off the humidifier. Beep the relay twice
      digitalWrite(humidifierPin, HIGH);
      delay(100);
      digitalWrite(humidifierPin, LOW);
      delay(600);
      digitalWrite(humidifierPin, HIGH);
      delay(100);
      digitalWrite(humidifierPin, LOW);
      statush = "off";
      tone(53,1000,100);lcd.clear();lcd.setCursor(0,0);lcd.print("HUM TURNING OFF");delay(1000);
    }
    if (h > highThresh){
      digitalWrite(fanPin, HIGH);
      tone(53,1000,100);lcd.clear();lcd.setCursor(0,0);lcd.print("FAN TURNING ON");delay(1000);
    }
    if (h < fanStopGap){
      digitalWrite(fanPin, LOW);
      tone(53,1000,100);lcd.clear();lcd.setCursor(0,0);lcd.print("FAN TURNING OFF");delay(1000);
    }
  }
  oldh = h;


  digitalWrite(ledPin, HIGH); //Flash the LED once the notify user that data collection is done and fan/humidifieres have been toggled
  delay(50);
  digitalWrite(ledPin, LOW);

  lcd.clear();
  lcd.setCursor(0,0);lcd.print("The HUM is " + statush);
  lcd.setCursor(0, 1);lcd.print("Temp:     " + String(t,1) + char(223) + "C");

  delay(loopDelay);

  lcd.clear();
  lcd.setCursor(0, 0);lcd.print("Humidity:    " + String(h) + char(37));
  lcd.setCursor(0, 1);lcd.print("Soil:       " + String(readSoil()));
  ///lcd.print("Soil Hum:N/A");

  delay(loopDelay);

  lcd.clear();
  lcd.setCursor(0, 0);lcd.print("CO2:  " + String(percentage));
  lcd.setCursor(13,0);lcd.print("ppm");
  lcd.setCursor(0, 1);lcd.print("Oxygen:    " + String(O2Percent,1) + char(37));


  Serial.print("==Run stats==\nO2:" + String(O2Percent) + char(37) + "\nTemp:" + String(t) + " " + char(223) + "C" + "\nSoil:" + String(readSoil()) + "\nAir:" + String(h) + char(37) + "\nCO2:" + String(percentage) + "ppm" + "\n\n\n");
  delay(loopDelay-100);
}


//This is a function used to get the soil moisture content
int readSoil() {
  digitalWrite(soilPower, HIGH);//turn D7 "On"
  delay(10);//wait 10 milliseconds
  soilval = analogRead(soilPin);//Read the SIG value form sensor
  digitalWrite(soilPower, LOW);//turn D7 "Off"
  newval = map(soilval, 595, 596, 0, 1);//"remap" the soil value to have a new zero value
  return newval;//send new moisture value
}

//This is a function used to calculate the CO2 ppm
int  MGGetPercentage(float analogValue) {
  float logConc=2.602 +(analogValue-V400)/slope; //計算目前二氧化碳的濃度log值
  return pow(10,logConc );

}

//This is a function used to retrieve the CO2 sensor resistance
float MGRead(int mg_pin) {
  int i;
  float v=0;

  for (i=0;i<READ_SAMPLE_TIMES;i++) {
    v += analogRead(mg_pin);
    delay(READ_SAMPLE_INTERVAL);
  }
  v =v/READ_SAMPLE_TIMES ;
  return v;
}

float readO2O2Vout()
{
    long sum = 0;
    for(int i=0; i<32; i++)
    {
        sum += analogRead(O2Pin);
    }

    sum >>= 5;

    float MeasuredO2Vout = sum * (VRefer / 1023.0);
    return MeasuredO2Vout;
}

float readConcentration()
{
    // O2Vout samples are with reference to 3.3V
    float MeasuredO2Vout = readO2O2Vout();

    //float Concentration = FmultiMap(MeasuredO2O2Vout, O2O2VoutArray,O2ConArray, 6);
    //when its output voltage is 2.0V,
    float Concentration = MeasuredO2Vout * 0.21 / 2.0;
    float Concentration_Percentage=Concentration*100;
    return Concentration_Percentage;
}