#include <RotaryEncoder.h>

constexpr byte PIN_IN1 = A1;
constexpr byte PIN_IN2 = A0;
constexpr byte PIN_IN3 = A3;
constexpr byte PIN_IN4 = A2;
constexpr byte PIN_IN5 = A5;
constexpr byte PIN_IN6 = A4;
constexpr byte PIN_IN7 = 4;
constexpr byte PIN_IN8 = 5;
constexpr byte PIN_IN9 = 2;
constexpr byte PIN_IN10 = 3;

RotaryEncoder *encoder1 = nullptr;
RotaryEncoder *encoder2 = nullptr;
RotaryEncoder *encoder3 = nullptr;
RotaryEncoder *encoder4 = nullptr;
RotaryEncoder *encoder5 = nullptr;

// Tastaturmatrix
int reihe[] = {6, 7, 8, 9};
int spalte[] = {13, 12, 11, 10};
int col_scan;
int last_scan = -1;

void setup()
{
  Serial.begin(9600);
  for (int i = 0; i <= 3; i++)
  {
    //Initialisierung der PINs
    pinMode(reihe[i], OUTPUT);
    pinMode(spalte[i], INPUT);
    digitalWrite(spalte[i], HIGH);
  }
  encoder1 = new RotaryEncoder(PIN_IN1, PIN_IN2, RotaryEncoder::LatchMode::FOUR3);
  encoder2 = new RotaryEncoder(PIN_IN3, PIN_IN4, RotaryEncoder::LatchMode::FOUR3);
  encoder3 = new RotaryEncoder(PIN_IN5, PIN_IN6, RotaryEncoder::LatchMode::FOUR3);
  encoder4 = new RotaryEncoder(PIN_IN7, PIN_IN8, RotaryEncoder::LatchMode::FOUR3);
  encoder5 = new RotaryEncoder(PIN_IN9, PIN_IN10, RotaryEncoder::LatchMode::FOUR3);
}

int pos1 = 0;
int pos2 = 0;
int pos3 = 0;
int pos4 = 0;
int pos5 = 0;

int Reihe;
int Spalte;

void loop()
{
  if (knopfGedrueckt(Reihe, Spalte)) {
    Aktion(Reihe, Spalte);
  }

  encoder1->tick(); // just call tick() to check the state.
  encoder2->tick();
  encoder3->tick();
  encoder4->tick();
  encoder5->tick();

  int newPos1 = encoder1->getPosition();
  int newPos2 = encoder2->getPosition();
  int newPos3 = encoder3->getPosition();
  int newPos4 = encoder4->getPosition();
  int newPos5 = encoder5->getPosition();

  if (true) {
    if (pos1 != newPos1) {
      Serial.print("pos1:");
      Serial.print(newPos1);
      Serial.print(" dir1:");
      Serial.println((int)(encoder1->getDirection()));
      pos1 = newPos1;
    }
    if (pos2 != newPos2) {
      Serial.print("pos2:");
      Serial.print(newPos2);
      Serial.print(" dir2:");
      Serial.println((int)(encoder2->getDirection()));
      pos2 = newPos2;
    }
    if (pos3 != newPos3) {
      Serial.print("pos3:");
      Serial.print(newPos3);
      Serial.print(" dir3:");
      Serial.println((int)(encoder3->getDirection()));
      pos3 = newPos3;
    }
    if (pos4 != newPos4) {
      Serial.print("pos4:");
      Serial.print(newPos4);
      Serial.print(" dir4:");
      Serial.println((int)(encoder4->getDirection()));
      pos4 = newPos4;
    }
    if (pos5 != newPos5) {
      Serial.print("pos5:");
      Serial.print(newPos5);
      Serial.print(" dir5:");
      Serial.println((int)(encoder5->getDirection()));
      pos5 = newPos5;
    }
  }
}

boolean knopfGedrueckt(int &Reihe, int &Spalte) {
  //Suche nach gedrücktem Knopf
  static boolean tasteGedrueckt = false;
  static unsigned long letzterDruck = 0;
  if (tasteGedrueckt && millis()-letzterDruck < 300) {  // Diese 300 ms verhindern, dass 
                                                        // der Tastendruck "prellt" bzw.
                                                        // schnell mehrfach hintereinander
                                                        // ausgeführt wird
    return false;
  }
  tasteGedrueckt = false;
  for (int i = 0; i <= 3; i++)
  {
    if (tasteGedrueckt) break;
    digitalWrite(reihe[0], HIGH);
    digitalWrite(reihe[1], HIGH);
    digitalWrite(reihe[2], HIGH);
    digitalWrite(reihe[3], HIGH);
    digitalWrite(reihe[i], LOW);

    for (int j = 0; j <= 3; j++)
    {
      col_scan = digitalRead(spalte[j]);
      if (col_scan == LOW)
      {
        letzterDruck = millis();
        tasteGedrueckt = true;
        Reihe  = i;
        Spalte = j;
        break;
      }
    }
  }
  return tasteGedrueckt;
}


void Aktion(int i, int j)
{
  int tasterNr = i*4+j+1;
  Serial.print("Taster Nr. ");
  Serial.print(tasterNr);
  Serial.print("\t");
  switch (tasterNr){
    case 1 : // Hier die Aktion für Taster 1
             Serial.println("Aktion für Taster 1");
        break;
    case 9 : // Hier die Aktion für Taster 9
             Serial.println("Aktion für Taster 9");
        break;
    case 16 : // Hier die Aktion für Taster 16
             Serial.println("Aktion für Taster 16");
        break;
    default: // und hier für alle eventuell nicht abgefangenen Tasternummern
             Serial.println("Hier ist noch keine Aktion hinterlegt ....");
        break;
  }
}