#define latchPin 15
#define clkPin 12
#define dataPin 13

#define pisoLatchPin 2
#define pisoDataPin 4

uint8_t ledState = 255;

void printBits(uint8_t data){
  int8_t i = 7;
  while(i>=0){
    Serial.print(bitRead(data, i));
    i--;
  }
}

void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  Serial.println("Initializing");

  //For SIPO
  pinMode(latchPin, OUTPUT);
  pinMode(clkPin, OUTPUT);
  pinMode(dataPin, OUTPUT);

  //For PISO
  pinMode(pisoLatchPin, OUTPUT);
  //pinMode(pisoClockPin, OUTPUT);
  pinMode(pisoDataPin, INPUT);

  digitalWrite(latchPin, LOW);
  digitalWrite(pisoLatchPin, HIGH);
  digitalWrite(clkPin, LOW);
  
  shiftOut(dataPin, clkPin, MSBFIRST, ledState);
  digitalWrite(latchPin, HIGH);
  digitalWrite(latchPin, LOW);
}

void loop() {
  // put your main code here, to run repeatedly:
  delay(10); // this speeds up the simulation

  // Step 1: Sample
  
  // Uncomment this line in Real World Application
  // digitalWrite(clkPin, HIGH);

  digitalWrite(pisoLatchPin, LOW);
  digitalWrite(pisoLatchPin, HIGH);

  uint8_t switchState = shiftIn(pisoDataPin, clkPin, MSBFIRST);
  Serial.print("Switch: ");
  printBits(switchState);
  Serial.println();

  if(ledState != switchState){
    ledState = switchState;
    shiftOut(dataPin, clkPin, MSBFIRST, ledState);
    digitalWrite(latchPin, HIGH);
    digitalWrite(latchPin, LOW);
    Serial.println("State Changed");
  }
  delay(1000);
}