/* Ivan Wong
 * 6/1/23
 * Don Heer
 * 24 Logging Final (Light Sensor)
 */

const int numReadings = 600;  // Amount of readings needed for 10 minutes
const int sensorPin = 32;
const float luxConversionFactor = 0.2; // Conversion factor from analog value to lux

int readings[numReadings];
int readIndex = 0;
unsigned int total = 0;
int average = 0;
int counter = 0;  // Tracks how many readings happened

unsigned long previousMillis = 0;
const unsigned long second = 1000;  // 1 second has 1000 milliseconds

void setup() {
  Serial.begin(115200);

  pinMode(sensorPin, INPUT);

// This allows for 600 readings, then resets the array back to 0
  for(int i = 0; i < numReadings; i++) {
    readings[i] = 0;
  }
}
void loop() {

// Current time
  unsigned long currentMillis = millis();

// previousMillis gets a 1000 added each second
  if((currentMillis - previousMillis) >= second) {
    previousMillis = currentMillis;

    unsigned int sensorVal = analogRead(sensorPin);
// readings array gets the sensor value
    readings[readIndex] = sensorVal;
    
// Calculates the total of the values
    total = total + readings[readIndex];

// readings arrray gets incremented by 1 each reading and the % prevents it from going over 600
    readIndex = (readIndex + 1) % numReadings;

// Increments counter by 1 for each reading
    counter++;

// Once there is 600 readings, we get the raw average
    if(counter >= numReadings) {
      average = total / numReadings;

      float luxAvg = average * luxConversionFactor;

      Serial.println(luxAvg);

// Resets everything back to 0 so we can read the next interval
      counter = 0;
      total = 0;
    }
  }
}