#include "DHT.h"//DHT Sensor Library

#define switchPin 22
#define relayPin 17
#define presencePin 33
#define tempPin 27

DHT dht(tempPin, DHT22);
int physicalSwitchState = 0;
boolean relayState = false;
boolean systemRelayState = false;
float temperature = 0;
boolean presenceState = 0;

void setup() {
  pinMode(switchPin, INPUT_PULLUP);
  pinMode(relayPin, OUTPUT);
  pinMode(presencePin, INPUT);
  dht.begin();
}

void loop() {
  checkForUpdates();
  int physicalSwitchRead = digitalRead(switchPin);
  if (physicalSwitchRead!=physicalSwitchState) physicalSwitchToggled(physicalSwitchRead);
  physicalSwitchState=physicalSwitchRead;
  digitalWrite(relayPin, (relayState ? HIGH : LOW));
  float temperatureRead = dht.readTemperature();
  if (temperatureRead != temperature) temperatureChanged(temperatureRead);
  temperature = temperatureRead;
  int presenceRead = digitalRead(presencePin);
  if (presenceRead != presenceState) presenceChanged(presenceRead);
  presenceState = presenceRead;
  delay(250);
}

void physicalSwitchToggled(int state){
  /*physical switch is manual override
  keeping the boiler turned on but cannot force
  it to turn off*/
  if (!systemRelayState){toggleRelay();}
  /*connect to IoT hub
  to update it about the physical switch
  has been toggled*/
}

void temperatureChanged(float temp){
  /*connect to IoT hub
  to update it that the temp has changed*/
}

void presenceChanged(int state){
  /*connect to IoT hub
  to update it that the presence has changed
  so the room has become occupied or unoccupied*/
}

void toggleRelay(){
  relayState = !relayState;
}

void checkForUpdates(){
  /*connect to IoT hub
  check if light value has updated
  if has updated then toggle the relay to keep in line*/
  /*not actually doing any IoT for this example but would
  call toggleRelay if the state had changed and
  update the systemRelayState*/
}