/*

https://forum.arduino.cc/t/press-button-and-have-led1-come-on-after-5s-delay-and-led2-simply-turn-on/1261609

*/



unsigned long lastPress = 0;       //just my attempt to use millis to achieve this goal somehow
unsigned long intervalDebounce = 50; //just my attempt to use millis to achieve this goal somehow
byte lastBtn = 1;//start high with input pullup

unsigned long lastWait;
unsigned long intervalWait = 5000;


#define BTN_PIN 3 //Push button on D3
#define LED1_PIN 4 //LED 1
#define LED2_PIN 5 //LED 2

int LED1_state = 0;
int LED2_state = 0;
//-----------------------------------------------------------------------
int state = 0;                      //integer to hold current state
int old = 0;                        //integer to hold last state
int buttonPoll = 0;                 //integer to hold button state
//------------------------------------------------------------------------

void setup() {
  Serial.begin(115200);
  pinMode(BTN_PIN, INPUT_PULLUP); //button as input activate internal pull up
  pinMode(LED1_PIN, OUTPUT);
  pinMode(LED2_PIN, OUTPUT);

}
//----------------------------------------------------------------------------------
void loop() {


  unsigned long now = millis();

  if (now - lastPress >= intervalDebounce) {
    byte b = digitalRead(BTN_PIN);
    if (b != lastBtn) {
      lastBtn = b;
      lastPress = now;//start debounce
      if (b) {
        //button press and released..
        lastWait = now;
        state++;
        if (state > 2) state = 1;
        Serial.print("Button Press state: ");
        Serial.println(state);
      }
    }
  }



  switch (state) {
    case 1:  ////LED1 turns on after 5s delay, and LED2 simply turns on
      if (now - lastWait >= intervalWait) {
        digitalWrite(LED1_PIN, HIGH); // on after a 5s delay
      } else digitalWrite(LED1_PIN, LOW);
      digitalWrite(LED2_PIN, HIGH); // on without delay
      break;

    case 2: ////LED1 simply turns on, and LED2 turns on after a 5s delay
      digitalWrite(LED1_PIN, HIGH); // on without delay
      if (now - lastWait >= intervalWait) {
        digitalWrite(LED2_PIN, HIGH); // on after 5s delay
      } else digitalWrite(LED2_PIN, LOW);
      break;

    default: //// both LED1 and LED2 simply turn on without delay
      digitalWrite(LED1_PIN, HIGH); //on without delay (achieved)
      digitalWrite(LED2_PIN, HIGH); //on without delay (achieved)
      break;

  }
}