#include <Button_SL.hpp> // https://github.com/DoImant/Button_SL

using ulong = unsigned long int;
enum class Condition : byte { ready, low, high };

class Timer {
public:
  void start() { timeStamp = millis(); }
  bool operator()(const ulong duration) const { return millis() - timeStamp >= duration; }

private:
  ulong timeStamp {0};
};

struct PinData {
  const uint8_t pin;
  const ulong tHigh;
  const ulong tLow;
};

Timer interval;
PinData pinData[] {
    {3, 500, 500},  // Pinnr, Time High, Time Low in Milliseconds
    {4, 500, 500},
    {4, 500, 500},
    {4, 500, 500},
    {5, 500, 500},
    {6, 500, 500},
    {5, 500, 500}
};

Btn::ButtonSL btn {2};

Condition onePeriod(const PinData& pd, Timer& tm, Condition state) {
  switch (state) {
    case Condition::ready:   // set given pin to HIGH (1)
      tm.start();
      {
        state = Condition::high;
        digitalWrite(pd.pin, HIGH);
      }
      break;
    case Condition::low:             // Wait for the end of the LOW period
      if (tm(pd.tLow)) {
        state = Condition::ready;    // One period (High/Low) has been completed
      }
      break;
    case Condition::high:            // Wait for the end of the HIGH period
      if (tm(pd.tHigh)) {
        tm.start();
        digitalWrite(pd.pin, LOW);   // Set Pin to LOW (0)
        state = Condition::low;
      }
      break;
    default: break;
  }
  return state;
}

void setup() {
  Serial.begin(115200);
  for (const auto& data : pinData) {
    pinMode(data.pin, OUTPUT);
  }
  btn.begin();
  btn.releaseOn();
}

void loop() {
  constexpr uint8_t sequenceSteps {sizeof(pinData) / sizeof(pinData[0])};
  static bool isActive {false};
  static size_t index {0};
  static Condition state {Condition::ready};

  if (btn.tick() != Btn::ButtonState::notPressed && !isActive) { 
    isActive = true; 
    Serial.println("Start");
  }

  if (isActive == true) {
    switch (index) {
      case 0 ... sequenceSteps-1:
        state = onePeriod(pinData[index], interval, state);
        if (state == Condition::ready) { ++index; }
        break;
      default:
        Serial.println("Ende");
        isActive = false;
        index = 0;
        break;
    }
  }
}