#include <Bounce2.h>

#define PIN_MODE INPUT_PULLUP
#define INTERVAL_IN_MS 10
#define TIMEOUT 2500

#define LED_RED 10
#define LED_YEL 9
#define LED_GRN 8

Bounce2::Button BTN_YEL = Bounce2::Button();
Bounce2::Button BTN_BLU = Bounce2::Button();
Bounce2::Button BTN_GRN = Bounce2::Button();

bool z1 = false;
int z = 0;
unsigned long last;

void setup() {
Serial.begin(9600); 
BTN_GRN.attach ( 5, PIN_MODE );
BTN_GRN.interval(INTERVAL_IN_MS);
BTN_GRN.setPressedState ( LOW );

BTN_BLU.attach ( 6, PIN_MODE );
BTN_BLU.interval(INTERVAL_IN_MS);
BTN_BLU.setPressedState ( LOW );

BTN_YEL.attach ( 7, PIN_MODE );
BTN_YEL.interval(INTERVAL_IN_MS);
BTN_YEL.setPressedState ( LOW );

pinMode(LED_RED, OUTPUT);
pinMode(LED_YEL, OUTPUT);
pinMode(LED_GRN, OUTPUT);
}

void loop() {
BTN_YEL.update();
BTN_BLU.update();
BTN_GRN.update();

Serial.print("Aktueller Zustand: ");
Serial.println(z);

switch(z) {
case 0:  // Startzustand
digitalWrite(LED_RED, HIGH);
digitalWrite(LED_YEL, LOW);
digitalWrite(LED_GRN, LOW);
if (BTN_GRN.pressed()) {
digitalWrite(LED_RED, LOW);
digitalWrite(LED_YEL, HIGH);
z = 1;
}
break;

case 1:  // Zustand 1
  digitalWrite(LED_RED, LOW);
  if (BTN_YEL.pressed()) {
    digitalWrite(LED_YEL, HIGH);
    z = 2;
  }
  else if (BTN_GRN.pressed()){
    z=0;
  }
  break;

case 2:  // Zustand 2
  if (BTN_BLU.pressed()) {
    digitalWrite(LED_YEL, HIGH);
    z = 3;
  }
  else if (BTN_GRN.pressed()){
    z=0;
  }
  break;

case 3:  // Zustand 3
  if (BTN_YEL.pressed()) {
    digitalWrite(LED_YEL, HIGH);
    z = 4;
  }
  else if (BTN_GRN.pressed()){
    z=0;
  }
  break;

case 4:  // Zustand 4
  if (BTN_BLU.pressed()) {
    digitalWrite(LED_YEL, HIGH);
    z = 5;
  }
  else if (BTN_GRN.pressed()){
    z=0;
  }
  break;

case 5:  // Zustand 5
  if (BTN_YEL.pressed()) {
    digitalWrite(LED_YEL, HIGH);
    z = 6;
  }
  else if (BTN_GRN.pressed()){
    z=0;
  }
  break;

case 6:  // Zustand 6
  if (BTN_GRN.pressed()) {
    digitalWrite(LED_YEL, LOW);
    digitalWrite(LED_GRN, HIGH);
    z = 0;
  }
  else if (BTN_YEL.pressed() || BTN_BLU.pressed()){
    z=0;
  }
  break;

default:
  z = 0;
  break;

}
}