/*
   2.8" ESP32-32E ILI9341
   20-Tasten Touch Keyboard

   16 normale Tasten + 4 Sondertasten
   Touch: XPT2046 / TFT_Touch
   Ausgabe: Display + Serial

   Basis:
   funktionierender Hersteller-Demo-Code
*/

#include <Arduino.h>
#include "TFT_eSPI.h"
#include <TFT_Touch.h>

// ------------------------------------------------------------
// TOUCH-PINS – aus der funktionierenden Hersteller-Demo
// ------------------------------------------------------------
#define RTP_DOUT 39
#define RTP_DIN  32
#define RTP_SCK  25
#define RTP_CS   33
#define RTP_IRQ  36

// ------------------------------------------------------------
// DISPLAY
// ------------------------------------------------------------
TFT_eSPI tft = TFT_eSPI();

TFT_Touch my_touch = TFT_Touch(
  RTP_CS,
  RTP_SCK,
  RTP_DIN,
  RTP_DOUT
);

// ------------------------------------------------------------
// TASTEN
// ------------------------------------------------------------

#define NUM_KEYS 20

// 4 Spalten x 5 Reihen
#define COLS 4
#define ROWS 5

#define KEY_W 68
#define KEY_H 32

#define KEY_X0 20    //36 von links
#define KEY_Y0 28    // 43 von oben

#define KEY_GAP_X 8
#define KEY_GAP_Y 7

// ------------------------------------------------------------
// TASTENBESCHRIFTUNG
// ------------------------------------------------------------

const char *keyLabel[NUM_KEYS] =
{
  "1",  "2",  "3",  "4",
  "5",  "6",  "7",  "8",
  "9",  "10", "11", "12",
  "13", "14", "15", "16",
  "S1", "S2", "S3", "S4"
};

// ------------------------------------------------------------
// TASTENCODES
//
// HIER kannst du später deine echten Codes eintragen.
// ------------------------------------------------------------

const uint8_t keyCode[NUM_KEYS] =
{
  0x01, 0x02, 0x03, 0x04,
  0x05, 0x06, 0x07, 0x08,
  0x09, 0x0A, 0x0B, 0x0C,
  0x0D, 0x0E, 0x0F, 0x10,

  0xF1, 0xF2, 0xF3, 0xF4
};

// ------------------------------------------------------------
// BUTTON-OBJEKTE
// ------------------------------------------------------------

TFT_eSPI_Button key_b[NUM_KEYS];

// verhindert mehrfaches Auslösen bei gehaltenem Finger
int lastKey = -1;


// ------------------------------------------------------------
// SETUP
// ------------------------------------------------------------

void setup()
{
  Serial.begin(115200);

  // Display starten
  tft.begin();

  // Landscape 320 x 240
  tft.setRotation(1);

  // ----------------------------------------------------------
  // DEINE FUNKTIONIERENDE TOUCH-KALIBRIERUNG
  // ----------------------------------------------------------

  my_touch.setCal(
    495,
    3398,
    721,
    3448,
    320,
    240,
    1
  );

  pinMode(RTP_IRQ, INPUT);

  // ----------------------------------------------------------
  // DISPLAY LÖSCHEN
  // ----------------------------------------------------------

  tft.fillScreen(TFT_BLACK);

  // Titel
  tft.setTextColor(TFT_WHITE, TFT_BLACK);
  tft.setTextFont(2);
  tft.setTextSize(1);
  tft.setCursor(8, 5);
  tft.print("TOUCH KEYBOARD");

  // ----------------------------------------------------------
  // TASTEN ZEICHNEN
  // ----------------------------------------------------------

  for (int i = 0; i < NUM_KEYS; i++)
  {
    int col = i % COLS;
    int row = i / COLS;

    int x = KEY_X0 + col * (KEY_W + KEY_GAP_X);
    int y = KEY_Y0 + row * (KEY_H + KEY_GAP_Y);

    key_b[i].initButton(
      &tft,

      x + KEY_W / 2,
      y + KEY_H / 2,

      KEY_W,
      KEY_H,

      TFT_WHITE,       // Rahmen
      TFT_DARKGREY,   // normal
      TFT_WHITE,       // Text

      "",
      1
    );

    key_b[i].drawButton(false, keyLabel[i]);
  }

  // ----------------------------------------------------------
  // STATUSZEILE
  // ----------------------------------------------------------

  tft.drawFastHLine(5, 220, 310, TFT_DARKGREY);// statuszeile linie

  tft.setTextFont(2);
  tft.setTextColor(TFT_YELLOW, TFT_BLACK);

  tft.setCursor(8, 224);     //statuszeile text
  tft.print("Taste: -    Code: ----");

  Serial.println();
  Serial.println("================================");
  Serial.println("20-Key Touch Keyboard");
  Serial.println("Bereit.");
  Serial.println("================================");
}


// ------------------------------------------------------------
// TASTE AUSGEBEN
// ------------------------------------------------------------

void sendKey(int key)
{
  Serial.print("Taste: ");
  Serial.print(keyLabel[key]);

  Serial.print("   Code: 0x");

  if (keyCode[key] < 0x10)
    Serial.print("0");

  Serial.println(keyCode[key], HEX);

  // ----------------------------------------------------------
  // STATUS AUF DISPLAY
  // ----------------------------------------------------------

  tft.fillRect(0, 226, 320, 14, TFT_BLACK);

  tft.setTextFont(2);
  tft.setTextColor(TFT_YELLOW, TFT_BLACK);

  tft.setCursor(8, 224);  //statuszeile text

  tft.print("Taste: ");
  tft.print(keyLabel[key]);

  tft.print("  Code: 0x");

  if (keyCode[key] < 0x10)
    tft.print("0");

  tft.print(keyCode[key], HEX);

  // ----------------------------------------------------------
  // HIER WIRD DER EIGENTLICHE CODE ALS BYTE GESENDET
  //
  // Aktuell über Serial.
  // ----------------------------------------------------------

  Serial.write(keyCode[key]);
}


// ------------------------------------------------------------
// LOOP
// ------------------------------------------------------------

void loop()
{
  bool pressed = my_touch.Pressed();

  // ----------------------------------------------------------
  // KEIN TOUCH
  // ----------------------------------------------------------

  if (!pressed)
  {
    if (lastKey >= 0)
    {
      key_b[lastKey].press(false);
      key_b[lastKey].drawButton(false, keyLabel[lastKey]);

      lastKey = -1;
    }

    delay(10);
    return;
  }

  // ----------------------------------------------------------
  // TOUCH-KOORDINATEN EINMAL LESEN
  // ----------------------------------------------------------

  uint16_t x = my_touch.X();
  uint16_t y = my_touch.Y();

  // ----------------------------------------------------------
  // PASSENDE TASTE SUCHEN
  // ----------------------------------------------------------

  int currentKey = -1;

  for (int i = 0; i < NUM_KEYS; i++)
  {
    if (key_b[i].contains(x, y))
    {
      currentKey = i;
      break;
    }
  }

  // ----------------------------------------------------------
  // NICHT AUF EINER TASTE
  // ----------------------------------------------------------

  if (currentKey < 0)
  {
    delay(10);
    return;
  }

  // ----------------------------------------------------------
  // ANDERE TASTE LOSLASSEN
  // ----------------------------------------------------------

  if (lastKey >= 0 && lastKey != currentKey)
  {
    key_b[lastKey].press(false);
    key_b[lastKey].drawButton(false, keyLabel[lastKey]);
  }

  // ----------------------------------------------------------
  // NEUE TASTE
  // ----------------------------------------------------------

  if (currentKey != lastKey)
  {
    key_b[currentKey].press(true);
    key_b[currentKey].drawButton(true, keyLabel[currentKey]);

    sendKey(currentKey);

    lastKey = currentKey;
  }

  delay(10);
}