/*
  74HC165 Shift register input example

  https://wokwi.com/arduino/projects/306031380875182657

  (C) 2021, Uri Shaked
*/

const int dataPin = 2;   /* Q7 */
const int clockPin = 3;  /* CP */
const int latchPin = 4;  /* PL */
//const int dataPin2 = 13;

// 8 * n : n 은 165가 연결된 갯수
#define numBits 8 *2  /* Set to 8 * number of shift registers */

int bits[numBits] = {0,};

void setup() {
  Serial.begin(115200);
  pinMode(dataPin, INPUT);
  //pinMode(dataPin2, INPUT);
  pinMode(clockPin, OUTPUT);
  pinMode(latchPin, OUTPUT);
}

void loop() {
  // Step 1: Sample
  digitalWrite(latchPin, LOW);
  digitalWrite(latchPin, HIGH);
  // Step 2: Shift
  Serial.print("Bits: ");
  for (int i = 0; i < numBits; i++) {
    bits[i] = digitalRead(dataPin);
    if (bits[i] == HIGH) {
      Serial.print("1");
    } else {
      Serial.print("0");
    }
    digitalWrite(clockPin, HIGH); // Shift out the next bit
    digitalWrite(clockPin, LOW);
  }

  Serial.println();
  KeyMapping(bits);
  delay(1000);
}

void KeyMapping(int *GetBits) {
  int firstIndex = 0, secondIndex = 0;
  int savedArray[numBits*numBits] = {0,};
  for(int i=0; i<numBits/2; i++){
    if(GetBits[i] == 1){
      for(int j= numBits/2; j<numBits; j++){
        if(GetBits[j] == 1){
          firstIndex = i;
          secondIndex = numBits/2 * (j - 8) + 1;
          savedArray[firstIndex + secondIndex - 1] = 1; 
        }
      }
    }
  }
  for(int i=0; i<numBits*numBits; i++){
    if(savedArray[i] == 1){
      Serial.print("Pressed Number : ");
      Serial.println(i + 1);
    }
  }
}