const int photo_resist=A1;

const int Button = 2;

int PhotoVal;
const int PinLed1 = 3;
const int PinLed2 = 10;
const int PinLed3 = 11;

unsigned long timeCount;
int MinVal = 1000;
int MaxVal = 0;

void setup() {

  // put your setup code here, to run once:

Serial.begin(9600);
pinMode (photo_resist, INPUT);
pinMode (Button, INPUT);

pinMode(PinLed1, OUTPUT);
pinMode(PinLed2, OUTPUT);
pinMode(PinLed3, OUTPUT);

calibrate();

}
void calibrate()
{
  digitalWrite(PinLed1,HIGH);
  delay(50);
  digitalWrite(PinLed1,LOW);
  timeCount = millis();
  while(millis()-timeCount <= 5000)
  {
    PhotoVal = analogRead(photo_resist);
    if ( PhotoVal < MinVal)
    {
      MinVal = PhotoVal;
    }
    if (PhotoVal > MaxVal)
    {
      MaxVal = PhotoVal;
    }
  }
  Serial.println("End of Calibration.");
  Serial.println("MAXVAL");
  Serial.println(MaxVal);

  digitalWrite(PinLed2,HIGH);
  delay(500);
  digitalWrite(PinLed2,LOW);
  Serial.println("MINVAL");
  Serial.println(MinVal);
}
void loop() {
  // put your main code here, to run repeatedly:
PhotoVal = analogRead(photo_resist);
Serial.println(PhotoVal);
PhotoVal = map(PhotoVal, 228,579,255,0);
PhotoVal = constrain(PhotoVal, 0,255);
analogWrite(PinLed1, PhotoVal);
analogWrite(PinLed2, PhotoVal);
analogWrite(PinLed3, PhotoVal);

}