// --- PIN DEFINITIES ---
const int dataPin595  = 2;
const int latchPin595 = 3;
const int clockPin595 = 6;

const int dataPin165  = 5;
const int loadPin165  = 7;
const int clockPin165 = 8;

// LED-status (4 wissels → 8 LEDs)
bool ledStatus[8] = {false};

// ----------------------------------------------------
void setup() {
  pinMode(dataPin595, OUTPUT);
  pinMode(latchPin595, OUTPUT);
  pinMode(clockPin595, OUTPUT);

  pinMode(dataPin165, INPUT_PULLUP);
  pinMode(loadPin165, OUTPUT);
  pinMode(clockPin165, OUTPUT);

  // Startstand: LED 1, 3, 5, 7 aan (rechtdoor)
  for (int w = 0; w < 4; w++) {
    ledStatus[w * 2]     = true;   // recht
    ledStatus[w * 2 + 1] = false;  // afbuigend
  }
}

// ----------------------------------------------------
void loop() {

  // --- 165 INLEZEN ---
  digitalWrite(loadPin165, LOW);
  delayMicroseconds(5);
  digitalWrite(loadPin165, HIGH);

  // BELANGRIJK: LSBFIRST ipv MSBFIRST
  byte buttons = shiftIn(dataPin165, clockPin165, LSBFIRST);

  // --- 4 WISSELS ONAFHANKELIJK VERWERKEN ---
  // bit 0 = knop 1, bit 1 = knop 2, ... bit 7 = knop 8
  for (int knop = 0; knop < 8; knop++) {

    bool pressed = !(buttons & (1 << knop)); // actief laag

    if (pressed) {

      int wissel  = knop / 2;          // 0..3
      bool afbuig = (knop % 2 == 1);   // even = recht, oneven = afbuigend

      int ledRecht = wissel * 2;       // 0,2,4,6
      int ledAf    = ledRecht + 1;     // 1,3,5,7

      ledStatus[ledRecht] = !afbuig;
      ledStatus[ledAf]    =  afbuig;
    }
  }

  // --- 595 OUTPUT OPBOUWEN ---
  // Q0 → LED1, Q1 → LED2, ... Q7 → LED8
  byte outByte = 0;
  for (int i = 0; i < 8; i++) {
    if (ledStatus[i]) outByte |= (1 << i);
  }

  digitalWrite(latchPin595, LOW);
  shiftOut(dataPin595, clockPin595, MSBFIRST, outByte);
  digitalWrite(latchPin595, HIGH);

  delay(10);
}