// ---------------------------------------------------------
// I2C - LCD Anzeige
// Pinning: ESP32 D22 <=> SCL I2C_LCD
//                D21 <=> SDA
//                3V3 <=> Vcc
//                GND <=> GND
// Befehle:
// oLCD.init ()
// oLCD.backlight ();
// oLCD.clear ();
// oLCD.setCursor (iSpalte,iZeile);
// oLCD.printf ("Hallo");
#include <LiquidCrystal_I2C.h>

#define I2C_ADDR    0x27
#define LCD_COLUMNS 16
#define LCD_LINES   2
#define BUTTON_UP   25
#define BUTTON_LEFT 26
#define BUTTON_DOWN 14
#define BUTTON_RIGHT 27

LiquidCrystal_I2C oLCD (I2C_ADDR, LCD_COLUMNS, LCD_LINES);
// ---------------------------------------------------------

char sWord[] = "Test";

void setup()
{
  oLCD.init();
  oLCD.backlight();  
  oLCD.printf("\n%s\n", sWord);

  Serial.begin(115200);
  Serial.println("Hello, ESP32!");
}


void loop()
{
  for(;;)
  {
    int iWordLength = 4;
    int iMaxRight = 15 - iWordLength;
    int iAllButtons[4] = {BUTTON_UP, BUTTON_LEFT, BUTTON_DOWN, BUTTON_RIGHT};
    int iRow = 0;
    int iCollum = 0;
    for(int iCount = 0; iCount <= 3; iCount++)
    {
      if (digitalRead(iAllButtons[iCount]))
      {
          Serial.println(iAllButtons[iCount]);
          oLCD.clear ();
          switch (iCount)
          {
            case 0:
              iRow++;break;
            case 1:
            iCollum--;break;
            case 2:
              iCollum++;break;
            case 3:
              iRow--;break;
          }

          if (iCollum > iMaxRight) iRow--;
          if (iCollum < 0) iRow++;
          if (iRow > 1) iRow--;
          if (iRow < 0) iRow++;


          oLCD.setCursor(iRow,iCollum);
          oLCD.printf("\n%s\n", sWord);
      }
    }
  }
}