// constants that won't change:
const byte button_pump = 7;
const byte pump_relais_pin = 5;

// variables that will change
bool pump_state = LOW;  // turns on (HIGH) or off (LOW) the realis
bool last_button_pump_state; // previous state of button pump
bool current_button_pump_state; // current state of button pump


void setup() {
  pinMode(button_pump, INPUT_PULLUP);
  pinMode(pump_relais_pin, OUTPUT);
  
  current_button_pump_state = digitalRead(button_pump);
}

void loop() {
  last_button_pump_state = current_button_pump_state;
  current_button_pump_state = digitalRead(button_pump);

  if(last_button_pump_state == HIGH && current_button_pump_state == LOW) {
    if (pump_state == LOW) {
      pump_state = HIGH;
    } else {
      pump_state = LOW;
    }
  digitalWrite(pump_relais_pin, pump_state);
  delay(200);
  while(!digitalRead(button_pump));
  }
}

// https://www.youtube.com/watch?v=ZoaUlquC6x8&ab_channel=RoboticsBack-End