#include <SPI.h>
#include <MFRC522.h>
#include <LiquidCrystal_I2C.h>

#define SS_PIN 10
#define RST_PIN 9
#define CHECK_BIT(var,pos) ((var) & (1<<(pos)))

MFRC522 mfrc522(SS_PIN, RST_PIN);   // Create MFRC522 instance.
LiquidCrystal_I2C lcd(0x27,20,4);

const int RFIDled = 6;
const int RFIDSound = 5;
const int RFIDbin = 3;
const int signalIN = A0;
const int TextKnob = A1;
const int textSound = A2;
long randNumber;

void setup() {
  Serial.begin(115200); // Initiate a serial communication
  SPI.begin(); // Initiate  SPI bus
  lcd.init();  // initialize the lcd 
  lcd.backlight();
  lcd.setCursor(3,0);
  mfrc522.PCD_Init(); // Initiate MFRC522

  Serial.println();

  pinMode(RFIDled, OUTPUT);
  pinMode(RFIDSound, OUTPUT);
  pinMode(RFIDbin, OUTPUT);
  pinMode(signalIN, INPUT);
  pinMode(TextKnob, INPUT);
  pinMode(textSound, OUTPUT);

}

void readCard() {
  // Look for new cards
  if ( ! mfrc522.PICC_IsNewCardPresent()) {
    return;
  }
  // Select one of the cards
  if ( ! mfrc522.PICC_ReadCardSerial()){
    return;
  }

  //Show UID on serial monitor
  Serial.print(" --- - ");
  String content = ""; // for tag + sound
  String binary = ""; // for binary + LED

  for (int i = 0; i < mfrc522.uid.size; i++) {
    Serial.print(mfrc522.uid.uidByte[i], DEC);
    content.concat(String(mfrc522.uid.uidByte[i], DEC));

    if (content.charAt(i) == '0') {
      tone(RFIDSound, 50, 799);
      delay(100);
    }
    else if (content.charAt(i) == '1') {
      tone(RFIDSound, 44, 880);
      delay(100);
    }
    else if (content.charAt(i) == '2') {
      tone(RFIDSound, 37, 8077);
      delay(100);
    }
    else if (content.charAt(i) == '3') {
      tone(RFIDSound, 34, 8090);
      delay(100);
    }
    else if (content.charAt(i) == '4') {
      tone(RFIDSound, 31, 1000);
      delay(100);
    }
    else if (content.charAt(i) == '5') {
      tone(RFIDSound, 45, 1200);
      delay(100);
    }
    else if (content.charAt(i) == '6') {
      tone(RFIDSound, 42, 7600);
      delay(100);
    }
    else if (content.charAt(i) == '7') {
      tone(RFIDSound, 7, 8000);
      delay(100);
    }
    else if (content.charAt(i) == '8') {
      tone(RFIDSound, 38, 6600);
      delay(100);
    }
    else if (content.charAt(i) == '9') {
      tone(RFIDSound, 39, 5550);
      delay(100);
    }
  }

  for (int b = 0; b < mfrc522.uid.size; b++) {
    // Serial.println(mfrc522.uid.uidByte[b], BIN);
    char r = mfrc522.uid.uidByte[b];

    for (int j = 8; j >= 0; j--) {
      if CHECK_BIT(r, j) {
        digitalWrite(RFIDled, HIGH);
        digitalWrite(RFIDbin, HIGH);
        delay(100);
      } else {
        digitalWrite(RFIDled, LOW);
        digitalWrite(RFIDbin, LOW);
        delay(100);
      }
      delay(100);
    }
  }
  Serial.println();
  delay(100);
}

//Q-code questions
const char *Qs[] = {
  "",
  "",
  "QRB? `- how far are you from my station?",
  "QRL? `- are you busy?",
  "QRZ? `- who is calling me?",
  "QRH? `- does my frequency vary?",
  "QRI? `- how is the tone of my transmission?",
  "QRK? `- what is the readability of my signals?",
  "QRM? `- do you have interference?",
  "QRN? `- are you troubled by static noise?",
  "QRQ? `- shall I send faster?",
  "QRT? `- shall I cease or suspend operation?",
  "QRU? `- have you anything for me?",
  "QRV? `- are you ready?",
  "QRX? `- shall I standby?",
  "QSA? `- what is the strength of my signals?",
  "QSB? `- are my signals fading?",
  "QSD? `- is my keying defective?",
  "QSL? `- can you acknowledge receipt?"
};

//Q-code answers/statements
const char *As[] = {
  "QRH -/ your frequency varies.",
  "QRL -/ i am busy. please do not interfere.",
  "QRM -/ i have interference.",
  "QRM -/ i am troubled by static noise.",
  "QRO -/ please increase transmit power.",
  "QRQ -/ please send faster.",
  "QRS -/ please send more slowly",
  "QRT -/ i am suspending operation.",
  "QRU -/ i have nothing for you.",
  "QRV -/ i am ready.",
  "QRX -/ please standby.",
  "QSB -/ your signals are fading.",
  "QSD -/ your keying is defective.",
  "QSK -/ i can hear you between my signals [while transmitting]; break in on my transmission.",
  "QSL -/ i am acknowledging receipt.",
  "QSM -/ repeat the last telegram which you sent me",
  "QSY -/ please change transmission frequency.",
  "QSZ -/ send each word or group twice."
};

void loop() {
  // put your main code here, to run repeatedly:
  readCard();
  int textnumber;
  int text = analogRead(TextKnob);
  textnumber = map(text, 1, 1023, 0, 18);

  if (textnumber > 1) { //when the knob is turned from the 'position 0'
    Serial.println(Qs[textnumber]);
    String question = Qs[textnumber];
    lcd.setCursor(0, 0); //Set the lcd cursor to the upper left corner
    lcd.print(Qs[textnumber]); //Display the specific Q-question on the fisrt row of LCD

    for (int positionCounter = 0; positionCounter < question.length(); positionCounter++) {
      lcd.scrollDisplayLeft(); //Q-question scrolls to the left
      delay(230);
    }
    
    const char* specQs = Qs[textnumber];
    // loop over each character of question
    for (int a = 0; a < strlen(specQs); a++ ) {
      char c = specQs[a];
      //Serial.print(c);
      //Serial.print(" ");
      //Serial.print(specQs[a], BIN);
      //Serial.println();

      // sonify the bits...
      for (int i = 7; i >= 0; i--) {
        if CHECK_BIT(c, i) {
          tone(textSound, 440, 100);
        } else {
          tone(textSound, 220, 100);
        }
        delay(100);
      }
    }
  }


  // give an answer
  randNumber = random(0, 17);
  int readSignal = digitalRead(signalIN);
  String randomQ = As[randNumber];

  if (readSignal) { //If the module receives a signal via A2 o4 input channel...
    Serial.println(As[randNumber]);
    lcd.setCursor(0, 1); //Set the lcd cursor to the lower left corner
    lcd.print(randomQ); //Displayes a random Q-answer from the answers array

    for (int counter = 0; counter < randomQ.length(); counter++) {
      lcd.scrollDisplayLeft(); //Q-answer dissapears in the left side of the LCD
      delay(230);
    }
  }
  delay(500);
}