// For: https://forum.arduino.cc/t/morse-code-circuit-with-timer/1071378
//
// 30 December 2022
//
// Changes by Koepel:
//   - Formatted the text.
//   - Added a timeout.
//   - Added a piezo buzzer, it needs the tone() function.
//   - Added the word "Pin" to the variable names for pins.
//   - Removed delay(1000); from loop().
//   - Moved the important functions to the top.
//   - Used 'tone()' for the buzzer.
//   - Added a LED next to the buzzer at pin 4, just for fun.
//   - Added functions StartAlarm and StopAlarm.
//   - Added 'bool' variable to indicate if alarm is on
//   - Renamed 'starTime' to 'startTime'.
//   - Added code to ignore LineFeed and CarriageReturn
//   - Reduced the timeout for Serial.readString() to 100ms
//   - Still thinking about the code.trim(), 
//     it also removes spaces at the beginning.
//   - Added UL to the number of 30000 for safety.
//

const int ledPin = 13;
const int buzPin = 5;
const int buttonPin = 10;
const int alarmLedPin = 4;

String code = "";
int len = 0;
char ch;
char new_char;
int unit_delay = 250;
bool pinState = true;
bool btnState = true;
bool prevBtnState = true;
bool alarm = false;

unsigned long interval = 30000UL;   // UL means Unsigned Long
unsigned long startTime = 0;

void setup() {
  // put your setup code here, to run once:
  Serial.begin (9600);
  Serial.setTimeout(100);      // 100 ms timeout for Serial.readString()
  pinMode(buttonPin, INPUT);
  pinMode(ledPin, OUTPUT);
  pinMode(buzPin, OUTPUT);
  pinMode(alarmLedPin, OUTPUT);

  Serial.println("I am ready...");
  startTime = millis();              // start the timer
}

void loop() {
  // put your main code here, to run repeatedly:
  while (Serial.available() > 0)
  {
    // Something has been entered, stop the alarm.
    if(alarm)           // check if alarm is on
    {
      StopAlarm();
      alarm = false;
    }

    code = Serial.readString();
    // code.trim();    // could be useful
    Serial.print(code);
    Serial.print(" = ");
    String2Morse();
    Serial.println("");

    startTime = millis();          // reset the timer
  }

  // The millis-timer runs on its own in the main section of the loop()
  if(millis() - startTime >= interval)
  {
    if(!alarm)        // check if the alarm is off
    {
      StartAlarm();
      alarm = true;
    }
  }
}

void StartAlarm () {
  // Only sound the buzzer, when the switch is turned on (to the right)
  if ( digitalRead(buttonPin) == HIGH)
    tone(buzPin, 230);

  digitalWrite(alarmLedPin, HIGH);
  Serial.println("TYPE SOMETHING BRO");
}

void StopAlarm () {
  // Stop the buzzer, regardless if it was on or off
  noTone(buzPin);
  digitalWrite(alarmLedPin, LOW);
}

void String2Morse()
{
  len = code.length();
  for (int i = 0; i < len; i++)
  {
    ch = code.charAt(i);
    morse();
  }
}

void dot()
{
  Serial.print(".");
  digitalWrite(ledPin, HIGH);
  tone(buzPin, 1000);
  delay(unit_delay);
  digitalWrite(ledPin, LOW);
  noTone(buzPin);
  delay(unit_delay);
}

void dash()
{
  Serial.print("-");
  digitalWrite(ledPin, HIGH);
  tone(buzPin, 1000);
  delay(unit_delay * 3);
  digitalWrite(ledPin, LOW);
  noTone(buzPin);
  delay(unit_delay);
}

void morse()
{
  if (ch == 'A' || ch == 'a')
  {
    A();
    Serial.print(" ");
  }
  else if (ch == 'B' || ch == 'b')
  {
    B();
    Serial.print(" ");
  }
  else if (ch == 'C' || ch == 'c')
  {
    C();
    Serial.print(" ");
  }
  else if (ch == 'D' || ch == 'd')
  {
    D();
    Serial.print(" ");
  }
  else if (ch == 'E' || ch == 'e')
  {
    E();
    Serial.print(" ");
  }
  else if (ch == 'f' || ch == 'f')
  {
    f();
    Serial.print(" ");
  }
  else if (ch == 'G' || ch == 'g')
  {
    G();
    Serial.print(" ");
  }
  else if (ch == 'H' || ch == 'h')
  {
    H();
    Serial.print(" ");
  }
  else if (ch == 'I' || ch == 'i')
  {
    I();
    Serial.print(" ");
  }
  else if (ch == 'J' || ch == 'j')
  {
    J();
    Serial.print(" ");
  }
  else if (ch == 'K' || ch == 'k')
  {
    K();
    Serial.print(" ");
  }
  else if (ch == 'L' || ch == 'l')
  {
    L();
    Serial.print(" ");
  }
  else if (ch == 'M' || ch == 'm')
  {
    M();
    Serial.print(" ");
  }
  else if (ch == 'N' || ch == 'n')
  {
    N();
    Serial.print(" ");
  }
  else if (ch == 'O' || ch == 'o')
  {
    O();
    Serial.print(" ");
  }
  else if (ch == 'P' || ch == 'p')
  {
    P();
    Serial.print(" ");
  }
  else if (ch == 'Q' || ch == 'q')
  {
    Q();
    Serial.print(" ");
  }
  else if (ch == 'R' || ch == 'r')
  {
    R();
    Serial.print(" ");
  }
  else if (ch == 'S' || ch == 's')
  {
    S();
    Serial.print(" ");
  }
  else if (ch == 'T' || ch == 't')
  {
    T();
    Serial.print(" ");
  }
  else if (ch == 'U' || ch == 'u')
  {
    U();
    Serial.print(" ");
  }
  else if (ch == 'V' || ch == 'v')
  {
    V();
    Serial.print(" ");
  }
  else if (ch == 'W' || ch == 'w')
  {
    W();
    Serial.print(" ");
  }
  else if (ch == 'X' || ch == 'x')
  {
    X();
    Serial.print(" ");
  }
  else if (ch == 'Y' || ch == 'y')
  {
    Y();
    Serial.print(" ");
  }
  else if (ch == 'Z' || ch == 'z')
  {
    Z();
    Serial.print(" ");
  }
  else if (ch == '0')
  {
    zero();
    Serial.print(" ");
  }
  else if (ch == '1')
  {
    one();
    Serial.print(" ");
  }
  else if (ch == '2')
  {
    two();
    Serial.print(" ");
  }
  else if (ch == '3')
  {
    three();
    Serial.print(" ");
  }
  else if (ch == '4')
  {
    four();
    Serial.print(" ");
  }
  else if (ch == '5')
  {
    five();
    Serial.print(" ");
  }
  else if (ch == '6')
  {
    six();
    Serial.print(" ");
  }
  else if (ch == '7')
  {
    seven();
    Serial.print(" ");
  }
  else if (ch == '8')
  {
    eight();
    Serial.print(" ");
  }
  else if (ch == '9')
  {
    nine();
    Serial.print(" ");
  }
  else if (ch == ' ')
  {
    delay(unit_delay * 7);
    Serial.print("/ ");
  }
  else if(ch == '\n' or ch == '\r')
  {
    // ignore the LineFeed and CarriageReturn
    // do nothing
  }
  else
    Serial.println("Unknown symbol!");
}

void A()
{
  dot();
  delay(unit_delay);
  dash();
  delay(unit_delay);
}

void B()
{
  dash();
  delay(unit_delay);
  dot();
  delay(unit_delay);
  dot();
  delay(unit_delay);
  dot();
  delay(unit_delay);
}

void C()
{
  dash();
  delay(unit_delay);
  dot();
  delay(unit_delay);
  dash();
  delay(unit_delay);
  dot();
  delay(unit_delay);
}

void D()
{
  dash();
  delay(unit_delay);
  dot();
  delay(unit_delay);
  dot();
  delay(unit_delay);
}

void E()
{
  dot();
  delay(unit_delay);
}

void f()
{
  dot();
  delay(unit_delay);
  dot();
  delay(unit_delay);
  dash();
  delay(unit_delay);
  dot();
  delay(unit_delay);
}

void G()
{
  dash();
  delay(unit_delay);
  dash();
  delay(unit_delay);
  dot();
  delay(unit_delay);
}

void H()
{
  dot();
  delay(unit_delay);
  dot();
  delay(unit_delay);
  dot();
  delay(unit_delay);
  dot();
  delay(unit_delay);
}

void I()
{
  dot();
  delay(unit_delay);
  dot();
  delay(unit_delay);
}

void J()
{
  dot();
  delay(unit_delay);
  dash();
  delay(unit_delay);
  dash();
  delay(unit_delay);
  dash();
  delay(unit_delay);
}

void K()
{
  dash();
  delay(unit_delay);
  dot();
  delay(unit_delay);
  dash();
  delay(unit_delay);
}

void L()
{
  dot();
  delay(unit_delay);
  dash();
  delay(unit_delay);
  dot();
  delay(unit_delay);
  dot();
  delay(unit_delay);
}

void M()
{
  dash();
  delay(unit_delay);
  dash();
  delay(unit_delay);
}

void N()
{
  dash();
  delay(unit_delay);
  dot();
  delay(unit_delay);
}

void O()
{
  dash();
  delay(unit_delay);
  dash();
  delay(unit_delay);
  dash();
  delay(unit_delay);
}

void P()
{
  dot();
  delay(unit_delay);
  dash();
  delay(unit_delay);
  dash();
  delay(unit_delay);
  dot();
}

void Q()
{
  dash();
  delay(unit_delay);
  dash();
  delay(unit_delay);
  dot();
  delay(unit_delay);
  dash();
  delay(unit_delay);
}

void R()
{
  dot();
  delay(unit_delay);
  dash();
  delay(unit_delay);
  dot();
  delay(unit_delay);
}

void S()
{
  dot();
  delay(unit_delay);
  dot();
  delay(unit_delay);
  dot();
  delay(unit_delay);
}

void T()
{
  dash();
  delay(unit_delay);
}

void U()
{
  dot();
  delay(unit_delay);
  dot();
  delay(unit_delay);
  dash();
  delay(unit_delay);
}

void V()
{
  dot();
  delay(unit_delay);
  dot();
  delay(unit_delay);
  dot();
  delay(unit_delay);
  dash();
  delay(unit_delay);
}

void W()
{
  dot();
  delay(unit_delay);
  dash();
  delay(unit_delay);
  dash();
  delay(unit_delay);
}

void X()
{
  dash();
  delay(unit_delay);
  dot();
  delay(unit_delay);
  dot();
  delay(unit_delay);
  dash();
  delay(unit_delay);
}

void Y()
{
  dash();
  delay(unit_delay);
  dot();
  delay(unit_delay);
  dash();
  delay(unit_delay);
  dash();
  delay(unit_delay);
}

void Z()
{
  dash();
  delay(unit_delay);
  dash();
  delay(unit_delay);
  dot();
  delay(unit_delay);
  dot();
  delay(unit_delay);
}

void one()
{
  dot();
  delay(unit_delay);
  dash();
  delay(unit_delay);
  dash();
  delay(unit_delay);
  dash();
  delay(unit_delay);
  dash();
  delay(unit_delay);
}

void two()
{
  dot();
  delay(unit_delay);
  dot();
  delay(unit_delay);
  dash();
  delay(unit_delay);
  dash();
  delay(unit_delay);
  dash();
  delay(unit_delay);
}

void three()
{
  dot();
  delay(unit_delay);
  dot();
  delay(unit_delay);
  dot();
  delay(unit_delay);
  dash();
  delay(unit_delay);
  dash();
  delay(unit_delay);
}

void four()
{
  dot();
  delay(unit_delay);
  dot();
  delay(unit_delay);
  dot();
  delay(unit_delay);
  dot();
  delay(unit_delay);
  dash();
  delay(unit_delay);
}

void five()
{
  dot();
  delay(unit_delay);
  dot();
  delay(unit_delay);
  dot();
  delay(unit_delay);
  dot();
  delay(unit_delay);
  dot();
  delay(unit_delay);
}

void six()
{
  dash();
  delay(unit_delay);
  dot();
  delay(unit_delay);
  dot();
  delay(unit_delay);
  dot();
  delay(unit_delay);
  dot();
  delay(unit_delay);
}

void seven()
{
  dash();
  delay(unit_delay);
  dash();
  delay(unit_delay);
  dot();
  delay(unit_delay);
  dot();
  delay(unit_delay);
  dot();
  delay(unit_delay);
}

void eight()
{
  dash();
  delay(unit_delay);
  dash();
  delay(unit_delay);
  dash();
  delay(unit_delay);
  dot();
  delay(unit_delay);
  dot();
  delay(unit_delay);
}

void nine()
{
  dash();
  delay(unit_delay);
  dash();
  delay(unit_delay);
  dash();
  delay(unit_delay);
  dash();
  delay(unit_delay);
  dot();
  delay(unit_delay);
}

void zero()
{
  dash();
  delay(unit_delay);
  dash();
  delay(unit_delay);
  dash();
  delay(unit_delay);
  dash();
  delay(unit_delay);
  dash();
  delay(unit_delay);
}