#define NUM_LED 3

//time translating//
#define sec * 1000
#define min * 60000
#define ms * 1

uint16_t millisOffset;
unsigned long currentMillis = millis();

//leds structure//
struct leds
{
  unsigned long startTime;       // The time this led is first active
  unsigned long stopTime;        // The time this led becomes inactive
  unsigned long minPulse;        // The minimum time the next pulse is generated
  unsigned long maxPulse;        // The maximum time the next pulse is generated
  unsigned long nextPulseStart;  // The time of the next pulse starts
  unsigned long nextPulseStop;   // The time of the next pulse  stops
  unsigned long pulseLength;     // The on time of the pulse
  uint8_t pin;                   // led GPIO pin number
};

leds myLeds[NUM_LED] = {0 min, 3 min, 3 sec, 12 sec, 0, 0, 100 ms, 2, //led num 0
                        1 min, 4 min, 3 sec, 12 sec, 0, 0, 100 ms, 3,//led num 1
                        2 min, 5 min, 3 sec, 12 sec, 0, 0, 100 ms, 4, //led num 2

                                      };


void setup() {
  // put your setup code here, to run once:
 Serial.begin(115200);
  for (uint8_t i = 0; i < NUM_LED; i++)
  {
    pinMode(myLeds[i].pin, OUTPUT);
  }
}

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


void startSequence()
{  
 currentMillis = millis() - millisOffset;
for (uint8_t x = 0; x < NUM_LED; x++)
  {
   
    // Is this solenoid active
    if (myLeds[x].startTime < currentMillis && myLeds[x].stopTime > currentMillis)
    {
      // Do we need to calculate a next pulse time?
  

      if (myLeds[x].nextPulseStop < currentMillis)
      {
        // Turn off solenoid
        digitalWrite(myLeds[x].pin, LOW);

        // Calculate nextPulseStart & nextPulseStop
        long  startOffset =random(myLeds[x].minPulse, myLeds[x].maxPulse);
        myLeds[x].nextPulseStart = startOffset + currentMillis;
        myLeds[x].nextPulseStop = myLeds[x].nextPulseStart + myLeds[x].pulseLength;
      }

      // Are we currently in the middle of a pulse?
      if (myLeds[x].nextPulseStart < currentMillis &&
          myLeds[x].nextPulseStop  > currentMillis)
      {
        //turn on solenoid
        digitalWrite(myLeds[x].pin, HIGH);
      }
    }
    
    if (currentMillis > myLeds[x].stopTime)
    {
      digitalWrite(myLeds[x].pin, LOW);   
    }

  }
 
 }