// PWM: 3, 5, 6, 9, 10, and 11. Provide 8-bit PWM output with the analogWrite() function.
byte LED_A = 3;
byte LED_B = 5;

#define STROBE_STATE_SLOW 1
#define STROBE_STATE_FAST 2
#define STROBE_STATE_NONE 3

class Strobe {
    byte slow, fast;
    byte state;
    byte led;
    boolean on;
    unsigned long next = 0;

public:
    boolean stopped = false;

    Strobe(byte l, byte s, byte f) {
        state = STROBE_STATE_SLOW;
        led = l;
        slow = s;
        fast = f;
        on = false;
    }

    boolean run() {
        if (next > 0 && (millis() < next)) {
            return false;
        }

        switch(state) {
        case STROBE_STATE_SLOW:
            on = !on;
            analogWrite(led, on ? 255 : 0);
            if(on) {
                next = millis() + 10;
                return false;
            } else {
                next = millis() + 300 + random(0, 300);
            }
            if(--slow <= 0) {
                state = STROBE_STATE_FAST;
            }
            return false;
        case STROBE_STATE_FAST:
            on = !on;
            analogWrite(led, on ? 255 : 0);
            if(on) {
                next = millis() + 10;
                return false;
            } else {
                next = millis() + 75 + random(0, 75);
            }
            if(--fast <= 0) {
                state = STROBE_STATE_NONE;
                on = false;
            }
            return false;
        default:
            if(!on) {
                analogWrite(led, 255);
                on = true;
                stopped = true;
                return true;
            }
        }
    }
};

void setup() {
    pinMode(2, INPUT_PULLUP);
    Serial.begin(9600);
}

void flash(byte led, byte duration)
{
    analogWrite(led, 255);
    delay(duration);
    analogWrite(led, 0);
}

void fade(byte led, byte stepDuration, byte stepSize, boolean in) {
    if(in) {
        for (int fadeValue = 0 ; fadeValue <= 255; fadeValue+=stepSize) {
            analogWrite(led, fadeValue);
            delay(stepDuration);
        }
    } else {
        for (int fadeValue = 255 ; fadeValue >=0;  fadeValue-=stepSize) {
            analogWrite(led, fadeValue);
            delay(stepDuration);
        }
    }
}

void fade(byte led, byte stepDuration, boolean in)
{
    fade(led, stepDuration, 1, in);
}

unsigned long lastMillis;

void loop() {
    delay(1000);

    Strobe s1 = Strobe(3, random(1,4), random(2, 6));
    Strobe s2 = Strobe(5, random(1,4), random(2, 6));

    while(!(s1.stopped && s2.stopped)) {
        if(lastMillis > millis()) {
            lastMillis = millis();
            return;
        }
        s1.stopped ? : s1.run();
        s2.stopped ? : s2.run();
        lastMillis = millis();
    }


    delay(2500);

    analogWrite(LED_A, 0);
    analogWrite(LED_B, 0);

    Serial.println(lastMillis);
    Serial.println(millis());
}