#define WOKWI  // For use with keyboard.h just make this line a comment -> //#define WOKWI

#ifdef WOKWI
  #define KEY_TAB "KEY_TAB"
  #define KEY_LEFT_SHIFT "KEY_LEFT_SHIFT"
  #define KEY_RETURN "KEY_RETURN"

  struct kbt {
    void begin();
    void write(String aKey);
    void press(String aKey);
    void release(String aKey);
  } Keyboard;

  void kbt::begin() {}

  void kbt::write(String aKey) {
    Serial.println(aKey + "_press&released");
  }

  void kbt::press(String aKey) {
    Serial.println(aKey + "_pressed");
  }

  void kbt::release(String aKey) {
    Serial.println(aKey + "_released");
  }

#else
  #include <Keyboard.h>
#endif


const int encoderClk = 2;  // Rotary encoder pin 1
const int encoderDT  = 3;  // Rotary encoder pin 2
const int buttonPin  = 4;    // Rotary encoder button pin

int section = 0;

const int numSections = 7;
const char* sectionNames[] = {"Text Entry", "Types", "Instruments", "Styles", "Banks", "User", "Blank Section"};


enum  Direction  {NONE, LEFT, RIGHT};

struct encoderType {
  byte buttonPin;
  byte encoderClk;
  byte encoderDT;
  boolean buttonReleased();
  Direction turned();
  void init(byte bPin, byte ClkPin, byte DTPin);
};

void encoderType::init(byte bPin, byte ClkPin, byte DTPin) {
  encoderType::encoderClk = ClkPin;
  encoderType::encoderDT = DTPin;
  encoderType::buttonPin = bPin;
  pinMode(ClkPin, INPUT_PULLUP);
  pinMode(DTPin, INPUT_PULLUP);
  pinMode(bPin, INPUT_PULLUP);
}

boolean encoderType::buttonReleased() {
  static unsigned lastChange = 0;
  static byte state = HIGH;
  static byte lastState = HIGH;
  byte actState = digitalRead(encoderType::buttonPin);
  if (actState != lastState) {
    lastChange = millis();
    lastState = actState;
  }
  if (state != lastState && millis() - lastChange > 30) {
    state = lastState;
    if (state) return true;
  }
  return false;
}

Direction encoderType::turned() {
  static int8_t rot_enc_table[] = {0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0};
  static uint8_t prevNextCode = 0;
  static uint16_t store=0;
  prevNextCode <<= 2;
  if (digitalRead(encoderType::encoderDT)) prevNextCode |= 0x02;
  if (digitalRead(encoderType::encoderClk)) prevNextCode |= 0x01;
  prevNextCode &= 0x0f;

   // If valid then store as 16 bit data.
   if  (rot_enc_table[prevNextCode] ) {
      store <<= 4;
      store |= prevNextCode;
      if ((store&0xff)==0x2b) return LEFT;
      if ((store&0xff)==0x17) return RIGHT;
   }
   return NONE;
}

encoderType myEncoder;

void setup() {
  Serial.begin(115200);
  myEncoder.init(buttonPin, encoderClk, encoderDT);
  Keyboard.begin();
}


void loop() {
  Direction d = myEncoder.turned();
  if (d == LEFT)   DecreaseSection();
  if (d == RIGHT)  IncreaseSection();
  if (myEncoder.buttonReleased()) SendReturn();
}

void SendReturn() {
  Keyboard.write(KEY_RETURN);
}

void IncreaseSection() {
  section++;
  if (section >= numSections) {
    section = 0;
  }
  Serial.println("section++\t" + String(section));
  if (section == 6) {
    // Send 5 tabs for Blank Section
    for (int i = 0; i < 5; i++) {
      Keyboard.write(KEY_TAB);
    }
  } else {
    Keyboard.write(KEY_TAB);
  }
  Serial.print("Section: ");
  Serial.println(sectionNames[section]);
}

void DecreaseSection() {
  section--;
  if (section < 0) {
    section = numSections - 1;
  }
  Serial.println("section--\t" + String(section));
  if (section == 6) {
    // Send 5 shift+tabs for Blank Section
    Keyboard.press(KEY_LEFT_SHIFT);
    for (int i = 0; i < 5; i++) {
      Keyboard.write(KEY_TAB);
    }
    Keyboard.release(KEY_LEFT_SHIFT);
  } else {
    Keyboard.press(KEY_LEFT_SHIFT);
    Keyboard.write(KEY_TAB);
    Keyboard.release(KEY_LEFT_SHIFT);
  }
  Serial.print("Section: ");
  Serial.println(sectionNames[section]);
}