#include <Stepper.h>

const int stepsPerRevolution = 200;
Stepper myStepper(stepsPerRevolution, D4, D7);

unsigned long startTime;
unsigned long selectedTime = 60000;
bool motorActivated = false;
int motorSpeed = 60;

void processCommand(String command) {
  if (command == "m_t1") {
    selectedTime = 60000;
    Serial.println("Selected: 1 minute");
  } else if (command == "m_t2") {
    selectedTime = 120000;
    Serial.println("Selected: 2 minutes");
  } else if (command == "m_start") {
    startMotor();
  } else if (command == "m_stop") {
    stopMotor();
    Serial.println("Engine stopped before the set time!");
  } else if (command == "m_v1") {
    setMotorSpeed(60);
  } else if (command == "m_v2") {
    setMotorSpeed(120);
  }
}

void setMotorSpeed(int speed) {
  motorSpeed = speed;
  myStepper.setSpeed(speed);
  Serial.print("Speed set to: ");
  Serial.println(speed);
}

void startMotor() {
  startTime = millis();
  motorActivated = true;
  digitalWrite(D14, HIGH);
  Serial.println("In progress...");
}

void stopMotor() {
  motorActivated = false;
}

void displayRemainingTime() {
  unsigned long currentTime = millis();

  if (currentTime - startTime >= selectedTime) {
    stopMotor();
    Serial.println("Done!");

    digitalWrite(D14, LOW);

    digitalWrite(D13, HIGH);
    digitalWrite(D5, HIGH);
    delay(2000);
    digitalWrite(D13, LOW);
    digitalWrite(D5, LOW);

    return;
  }

  myStepper.step(stepsPerRevolution);
  delay(1);

  if (Serial.available() > 0) {
    String command = Serial.readStringUntil('\n');
    processCommand(command);
  }

  unsigned long elapsedTime = currentTime - startTime;
  unsigned long remainingTime = (selectedTime - elapsedTime) / 1000;

  unsigned int minutes = remainingTime / 60;
  unsigned int seconds = remainingTime % 60;

  Serial.print("Tempo rimanente: ");
  Serial.print(minutes);
  Serial.print(" minuti ");
  Serial.print(seconds);
  Serial.println(" secondi");
}

void setup() {
  myStepper.setSpeed(motorSpeed);
  Serial.begin(9600);
  Serial.println("[Simulation]");
  pinMode(D13, OUTPUT);
  pinMode(D14, OUTPUT);
  pinMode(D15, OUTPUT);
  pinMode(D5, OUTPUT);
}

void loop() {
  digitalWrite(D15, HIGH);

  if (Serial.available() > 0) {
    String command = Serial.readStringUntil('\n');
    processCommand(command);
  }

  if (motorActivated) {
    displayRemainingTime();
  }
}