const int photoPin=A0;
int photoValue=0;
int lightVal=0;
const int PinRed=9;
const int PinGreen=10;
const int PinBlue=11;
const int pinButt=6;
int newButt=0;
int lastButt=0;
int minimum = 1000;
int maximum = -1000;
unsigned long timeVal;

void setup()
{
  // put your setup code here, to run once:

Serial.begin(9600);
pinMode(photoPin, INPUT);
pinMode (PinRed, OUTPUT);
pinMode (PinBlue, OUTPUT);
pinMode(PinGreen, OUTPUT);
analogWrite(PinRed, 255);
analogWrite(PinGreen, 0);
analogWrite(PinBlue, 0);
delay (500);
analogWrite(PinRed, 0);
analogWrite(PinGreen, 255);
analogWrite(PinBlue, 0);
delay(500);
analogWrite(PinRed, 0);
analogWrite(PinGreen, 0);
analogWrite(PinBlue, 255);
}
void calibrate ()
{
  minimum = 1000;
  maximum = -1000;
  analogWrite (PinGreen, HIGH);
  timeVal =millis();
while (millis ()-timeVal<5000)
{
  photoValue = analogRead(photoPin);
  if (photoValue > maximum)
  {
    maximum = photoValue;
  }
  else if (photoValue < minimum)
  {
    minimum = photoValue;
  }
}
Serial.println(minimum);
Serial.println(maximum);
digitalWrite (PinGreen, LOW);
}
boolean debounce (boolean last)
{
  boolean current = digitalRead(pinButt);
  if (last != current)
  {
    delay(5);
    current = digitalRead(pinButt);
  }
  return current;
}

void loop()
{
  // put your main code here, to run repeatedly:
newButt = debounce (lastButt);
  if(newButt==HIGH && lastButt ==LOW)
  {
   calibrate();
  }
  lastButt=newButt;

photoValue=analogRead (photoPin);
lightVal=map (photoValue, minimum, maximum, 255, 0);
lightVal=constrain (lightVal, 0, 255);
analogWrite (PinRed, lightVal);
analogWrite (PinGreen,lightVal);
}