/* 
Mehdi Sadraei

Note:
For writing Fade for a LED, the analogWrite(led,9) is used; 
Since analogewrite uses 1-225 records, I have to use an "if clause" to
divide regions less than 1 and greater than 1. because LED does not detect (0-1) 
voltages and in this region would be off.


*/

// These constants should match the photoresistor's "gamma" and "rl10" attributes
const float GAMMA = 0.7;
const float RL10 = 50;
int led = 9;           // the PWM pin the LED is attached to
int Daylight=0;

void setup() {

 pinMode(led, OUTPUT);

 Serial.begin(9600);
}

void loop() {
  // put your main code here, to run repeatedly:


// Convert the analog value into lux value:
int analogValue = analogRead(A0);
float voltage = analogValue / 1024. * 5;
float resistance = 2000 * voltage / (1 - voltage / 5);
float lux = pow(RL10 * 1e3 * pow(10, GAMMA) / resistance, (1 / GAMMA));

  
if ((0 <lux) && (lux < 445 )) 
{
    float Daylight = (lux / 100000.)+1;
    analogWrite(led, Daylight);
    Serial.println(Daylight);
  }
  else 
  {
      float Daylight = lux / 100000. * 223;
      
   analogWrite(led, analogValue);
   Serial.println(Daylight);
  }
 
}