#include <LiquidCrystal.h>
 
// select the pins used on the LCD panel
LiquidCrystal lcd(8, 9, 4, 5, 6, 7);
 
// define some values used by the panel and buttons
int lcd_key     = 0;
int adc_key_in  = 0;
#define btnRIGHT  0
#define btnUP     1
#define btnDOWN   2
#define btnLEFT   36
#define btnSELECT 4
#define btnNONE   5
 
#define BUZZER_PIN 12
#define LED_PIN 13
 
char currentChar[16], bigWord[16], buzzerMorse[100];
int charIndex = 0, wordIndex = 0, buzzerIndex = 0;
int isReady = 0, isSelect = 0;
 
// read the buttons
int read_LCD_buttons()
{
 adc_key_in = analogRead(0);      // read the value from the sensor 
 // my buttons when read are centered at these valies: 0, 144, 329, 504, 741
 // we add approx 50 to those values and check to see if we are close
 if (adc_key_in > 1500) return btnNONE; // We make this the 1st option for speed reasons since it will be the most likely result
 if (adc_key_in < 50)   return btnRIGHT;  
 if (adc_key_in < 195)  return btnUP; 
 if (adc_key_in < 380)  return btnDOWN; 
 if (adc_key_in < 500)  return btnLEFT; 
 if (adc_key_in < 700)  return btnSELECT;   
 return btnNONE;  // when all others fail, return this...
}
 
void silence() {
  digitalWrite(BUZZER_PIN, HIGH);
}
 
void buzz() {
  digitalWrite(BUZZER_PIN, LOW);
}
 
void led_on() {
  digitalWrite(LED_PIN, HIGH);
}
 
void led_of() {
  digitalWrite(LED_PIN, LOW);
}
 
void print_word() {
  lcd.setCursor(0,1);            // move to the begining of the second line
 
  for (int i = 0; i < wordIndex; ++i) {
    lcd.print(bigWord[i]);
  }
}
 
void print_char() {
  lcd.setCursor(wordIndex,1);            // move to the end of the word
 
  for (int i = 0; i < charIndex; ++i) {
    lcd.print(currentChar[i]);
  }
}
 
 
void print_morse(int start) {
  lcd.setCursor(0,1);            // move to the begining of the second line
 
  for (int i = start; i < buzzerIndex; ++i) {
    lcd.print(buzzerMorse[i]);
  }
}
 
int get_signal_duration() {
  unsigned long start = millis();
 
  while (lcd_key == btnRIGHT) {
    lcd_key = read_LCD_buttons();
  }
 
  unsigned long finish = millis();
  return finish - start;
}
 
char get_char_from_signal() {
  unsigned long duration = get_signal_duration();
 
  if (duration > 500) {
    return '-';
  }
 
  return '.';
}
 
char morse1() {
  if (currentChar[0] == '.') {
    return 'E'; 
  }
 
  return 'T';
} 
 
char morse2() {
  if (currentChar[0] == '.' && currentChar[1] == '.') {
    return 'I';
  }
  if (currentChar[0] == '.' && currentChar[1] == '-') {
    return 'A';
  }
  if (currentChar[0] == '-' && currentChar[1] == '.') {
    return 'N';
  }
  if (currentChar[0] == '-' && currentChar[1] == '-') {
    return 'M';
  }
} 
 
char morse3() {
  if (currentChar[0] == '.' && currentChar[1] == '.' && currentChar[2] == '.') {
    return 'S';
  } else if (currentChar[0] == '.' && currentChar[1] == '.' && currentChar[2] == '-') {
    return 'U';
  } else if (currentChar[0] == '.' && currentChar[1] == '-' && currentChar[2] == '.') {
    return 'R';
  } else if (currentChar[0] == '.' && currentChar[1] == '-' && currentChar[2] == '-') {
    return 'W';
  } else if (currentChar[0] == '-' && currentChar[1] == '.' && currentChar[2] == '.') {
    return 'D';
  } else if (currentChar[0] == '-' && currentChar[1] == '.' && currentChar[2] == '-') {
    return 'K';
  } else if (currentChar[0] == '-' && currentChar[1] == '-' && currentChar[2] == '.') {
    return 'G';
  } else if (currentChar[0] == '-' && currentChar[1] == '-' && currentChar[2] == '-') {
    return 'O';
  }
 
} 
 
char morse4() {
  if (currentChar[0] == '.' && currentChar[1] == '.' && currentChar[2] == '.' && currentChar[3] == '.') {
    return 'H';
  } else if (currentChar[0] == '.' && currentChar[1] == '.' && currentChar[2] == '.' && currentChar[3] == '-') {
    return 'V';
  } else if (currentChar[0] == '.' && currentChar[1] == '.' && currentChar[2] == '-' && currentChar[3] == '.') {
    return 'F';
  } else if (currentChar[0] == '.' && currentChar[1] == '-' && currentChar[2] == '.' && currentChar[3] == '.') {
    return 'L';
  } else if (currentChar[0] == '.' && currentChar[1] == '-' && currentChar[2] == '-' && currentChar[3] == '.') {
    return 'P';
  } else if (currentChar[0] == '.' && currentChar[1] == '-' && currentChar[2] == '-' && currentChar[3] == '-') {
    return 'J';
  } else if (currentChar[0] == '-' && currentChar[1] == '.' && currentChar[2] == '.' && currentChar[3] == '.') {
    return 'B';
  } else if (currentChar[0] == '-' && currentChar[1] == '.' && currentChar[2] == '.' && currentChar[3] == '-') {
    return 'X';
  } else if (currentChar[0] == '-' && currentChar[1] == '.' && currentChar[2] == '-' && currentChar[3] == '.') {
    return 'C';
  } else if (currentChar[0] == '-' && currentChar[1] == '.' && currentChar[2] == '-' && currentChar[3] == '-') {
    return 'Y';
  } else if (currentChar[0] == '-' && currentChar[1] == '-' && currentChar[2] == '.' && currentChar[3] == '.') {
    return 'Z';
  } else if (currentChar[0] == '-' && currentChar[1] == '-' && currentChar[2] == '.' && currentChar[3] == '-') {
    return 'Q';
  } else if (currentChar[0] == '-' && currentChar[1] == '-' && currentChar[2] == '-' && currentChar[3] == '-') {
    return ' ';
  }
} 
 
char morse_to_char() {
  switch (charIndex) {
    case 1: {
        return morse1();
    }
    case 2: {
        char c = morse2();
        return c;
    }
    case 3: {
        return morse3() ;
    }
    case 4: {
        return morse4();
    }  
    default: {
      return ' ';
    }
  }
}
 
char get_letter_from_morse() {
  char sol = morse_to_char();
 
  charIndex = 0;
  lcd.setCursor(wordIndex,1); 
  lcd.print("               "); 
  return sol;  
}
 
void prepare() {
  lcd.setCursor(0,1);
  lcd.print("               ");
  lcd.setCursor(0,0);
  lcd.print("Track the buzzer!");
}
 
void morse_to_buzzer() {
  delay(1500);
 
 
  for (int i = 0; i < buzzerIndex; ++i) {
    prepare();
    print_morse(i);
 
    if (buzzerMorse[i] == '.') {
      buzz();
      led_on();
      delay(300);
      silence();
      led_of();
    } else if (buzzerMorse[i] == '-') {
      buzz();
      led_on();
      delay(900);
      silence();
      led_of();
    } else {
      delay(400);
    }
 
    delay (200);
  }
}
 
void cleanup() {
  lcd.setCursor(0,0);
  lcd.print("Use morse code:   ");
  lcd.setCursor(0,1);
  lcd.print("                ");
  charIndex = 0;
  wordIndex = 0;
  buzzerIndex = 0;
}
 
void setup()
{
  pinMode(BUZZER_PIN, OUTPUT);
  pinMode(LED_PIN, OUTPUT);
  lcd.begin(16, 2);              // start the library
  lcd.setCursor(0,0);
  lcd.print("Use morse code:"); 
}
 
void loop()
{
  silence();
  lcd_key = read_LCD_buttons();  // read the buttons
 
  print_word();
  print_char();
 
  switch (lcd_key)               // depending on which button was pushed, we perform an action
  {
   case btnRIGHT:
      {
        isReady = 0;
        isSelect = 0;
        char sig = get_char_from_signal();
        currentChar[charIndex++] = sig;
        buzzerMorse[buzzerIndex++] = sig;
        break;
      }
   case btnLEFT:
      {
        isSelect = 0;
        if (!isReady) {
          isReady = 1;
          buzzerMorse[buzzerIndex++] = ' ';
          bigWord[wordIndex++] = get_letter_from_morse(); 
        }
 
        break;
      }
 
   case btnSELECT:
     {
        if (!isSelect) {
          isSelect = 1;
 
          prepare();
          morse_to_buzzer();
          cleanup();
        }
       break;
     }
   case btnNONE:
     {
       break;
     }
  }
}