Group 2 MEGR 3171 Automatic Plant Watering System

// This #include statement was automatically added by the Particle IDE.
#include <Grove_Temperature_And_Humidity_Sensor.h>//Library needed for the temp and humidity sensor (DHT)
#include <math.h>//library needed for pow() function

#define DHTPIN D2 //defining what pin will be used for the DHT sensor
DHT dht(DHTPIN);

int sensorPin = A3;//Pin that will be used for capacitance moisture sensor input

//Initalizing values used later in code
int val;
int getTemp;
int getHumid;
String moisture_percent;

void setup() {
    dht.begin();
    pinMode(sensorPin, INPUT); 
   
    //Defining particle variables that will read us the values we want to see
    Particle.variable("Temp F", getTemp);
    Particle.variable("Humidity Analog Value", getHumid);
    Particle.variable("Moisture Percent", moisture_percent);
}

void loop() {
    //Aquiring sensor values:
    getTemp = dht.getTempFarenheit();//gets temp
    getHumid = dht.getHumidity();//gets humidity
    val = analogRead(sensorPin);//gets analog signal input
    moisture_percent = calcMoisturePercent(val);//takes analog sensor input and uses function to calc moisture percent
    
    delay(3000);//Values are recalculated every 3 seconds, mainly due DHT sensor only being able to take readings every few seconds

    Particle.publish("MoisturePercent", String(moisture_percent));
}


String calcMoisturePercent(int value){ //takes in analog sensor value and will return moisture percent
    //Capacitance moisture sensor calibration:
    int moisture_0 =2899;//Value in "dry" air, will act as our 0% reading
    int moisture_100 = 2100;//Value in water, will act as 100% reading
    
    if (value <= moisture_0 && value >= moisture_100){
        int mp = (value - moisture_0) * pow(moisture_100 - moisture_0, -1) * 100;//Formula came from Thermodynamics quaility formula lol
        return String(mp) +"%  " + String(value);
    }
    else {
        return "ERROR, " + String(value); // Will return error and sensor value if sensor reading is not within calibration values
    }
}