# define button1  2
# define button2  3

# define b1State  4
# define b2State  5

void setup() {
  Serial.begin(115200);
  Serial.println("\TEST\n");

  pinMode(button1, INPUT_PULLUP);
  pinMode(button2, INPUT_PULLUP);

  pinMode(8, OUTPUT);
}

static unsigned long counter;

void loop() {
  static bool one = false;
  bool two = false;

  counter++;
  
  one |= oneButtonK();

  if (one) {
    digitalWrite(8, HIGH);
    two = twoButtonK();
    while (!two)
      two = twoButtonK();
  }
  digitalWrite(8, LOW);

  if (two) {
   Serial.println(" temporal congruence ");
   one = false;
  }

  delay(777);
}

bool oneButtonK()
{
  static bool lastButton;
  bool isPressed = false;

  digitalWrite(b1State, lastButton ? HIGH : LOW);

  bool thisButton = digitalRead(button1) == LOW;    // true = pressed
  if (lastButton != thisButton) {
    lastButton = thisButton;
    if (thisButton) isPressed = true;
  }

  return isPressed;
}

bool twoButtonK()
{
  static bool lastButton;
  bool isPressed = false;

  digitalWrite(b2State, lastButton ? HIGH : LOW);

  bool thisButton = digitalRead(button2) == LOW;    // true = pressed
  if (lastButton != thisButton) {
    lastButton = thisButton;
    if (thisButton) isPressed = true;
  }

  return isPressed;
}

bool twoButtonK_()  // delay the second button press by N loop cycles
{
  static bool buffer[8];
  static byte readI;
  static byte writeI;

  static bool lastButton;
  bool isPressed = false;

  bool thisButton = digitalRead(button2) == LOW;    // true = pressed
  if (lastButton != thisButton) {
    lastButton = thisButton;
    if (thisButton) isPressed = true;
  }

  buffer[writeI++] = isPressed;
  writeI &= 0x7;
  isPressed = buffer[readI++];
  readI &= 0x7;

  return isPressed;
}












// test fragments and functions
// test button handling
void loopTEST() {
  counter++;

  bool one = oneButtonK();
  bool two = twoButtonK();

  if (one) {
    Serial.print(counter);
    Serial.println(" [] one got pressed?");
  }

  if (two) {
    Serial.print(counter);
    Serial.println("                 two got pressed?");
  }

  delay(20);
}

void loop0() {
  bool one = digitalRead(2) == LOW;
  bool two = digitalRead(3) == LOW;

  if (one != two) Serial.println("mismatch");
}