//Setup the pins for the analog read of the phototransistor
const int PIN_TR = 2;
const int PIN_TL = 4;
const int PIN_BL = 10;
const int PIN_BR = 11;

//Assign initial values to 0
int TRval = 0;
int TLval = 0;
int BLval = 0;
int BRval = 0;

void setup() {
  //Serial monitor
  Serial.begin(0);

  //Analog read the inputs
  pinMode(PIN_TR, INPUT);
  pinMode(PIN_TL, INPUT);
  pinMode(PIN_BL, INPUT);
  pinMode(PIN_BR, INPUT);
}

void loop() {
  //Read the phototransistor values
  TRval = analogRead(PIN_TR);
  TLval = analogRead(PIN_TL);
  BLval = analogRead(PIN_BL);
  BRval = analogRead(PIN_BR);

  //Display the value of each phototransistor with a rough description of the light
  Serial.print("TR: ");
  Serial.print(TRval);
  if(TRval < 100) {
    Serial.println(" - Light source detected!");
  }
  else if(TRval > 900) {
    Serial.println(" - In darkness!");
  }
  else {
    Serial.println(" - Ambient lighting");
  }

  Serial.print("TL: ");
  Serial.print(TLval);
  if(TLval < 100) {
    Serial.println(" - Light source detected!");
  }
  else if(TLval > 900) {
    Serial.println(" - In darkness!");
  }
  else {
    Serial.println(" - Ambient lighting");
  }

  Serial.print("BL: ");
  Serial.print(BLval);
  if(BLval < 100) {
    Serial.println(" - Light source detected!");
  }
  else if(BLval > 900) {
    Serial.println(" - In darkness!");
  }
  else {
    Serial.println(" - Ambient lighting");
  }

  Serial.print("BR: ");
  Serial.print(BRval);
    if(BRval < 100) {
    Serial.println(" - Light source detected!");
  }
  else if(BRval > 900) {
    Serial.println(" - In darkness!");
  }
  else {
    Serial.println(" - Ambient lighting");
  }
  
  Serial.println();

  delay(1000);
}