#include <Adafruit_GFX.h>
#include <Adafruit_ILI9341.h>
#include <SPI.h>

#define TFT_DC 2
#define TFT_CS 15
#define TFT_RST 4
#define TFT_MOSI 23
#define TFT_CLK 18
#define TFT_MISO 19

#define BTN_UP 5
#define BTN_DOWN 18
#define BTN_LEFT 19
#define BTN_RIGHT 21

Adafruit_ILI9341 tft = Adafruit_ILI9341(TFT_CS, TFT_DC, TFT_MOSI, TFT_CLK, TFT_RST, TFT_MISO);

int pixelX = 160;  // Initial X position
int pixelY = 120;  // Initial Y position
const int pixelSize = 10;  // Size of the pixel
const uint16_t pixelColor = ILI9341_GREEN;  // Color of the pixel
const uint16_t bgColor = ILI9341_CYAN;  // Background color

void setup() {
  Serial.begin(115200);
  
  // Increase SPI clock speed for faster drawing
  SPI.begin();
  SPI.setFrequency(40000000);
  
  tft.begin();
  tft.setRotation(1);  // Landscape mode
  
  // Fast fill screen
  tft.startWrite();
  tft.writeColor(bgColor, 320 * 240);
  tft.endWrite();
  
  // Draw border using fast horizontal and vertical line drawing
  tft.startWrite();
  tft.writeFastHLine(0, 0, tft.width(), ILI9341_WHITE);
  tft.writeFastHLine(0, tft.height() - 1, tft.width(), ILI9341_WHITE);
  tft.writeFastVLine(0, 0, tft.height(), ILI9341_WHITE);
  tft.writeFastVLine(tft.width() - 1, 0, tft.height(), ILI9341_WHITE);
  tft.endWrite();
  
  // Set up button pins
  pinMode(BTN_UP, INPUT_PULLUP);
  pinMode(BTN_DOWN, INPUT_PULLUP);
  pinMode(BTN_LEFT, INPUT_PULLUP);
  pinMode(BTN_RIGHT, INPUT_PULLUP);
  
  drawPixel();
  
  Serial.println("Setup complete");
}

void loop() {
  int dx = 0, dy = 0;
  
  // Check button states
  if (digitalRead(BTN_UP) == LOW) dy = -1;
  if (digitalRead(BTN_DOWN) == LOW) dy = 1;
  if (digitalRead(BTN_LEFT) == LOW) dx = -1;
  if (digitalRead(BTN_RIGHT) == LOW) dx = 1;
  
  if (dx != 0 || dy != 0) {
    movePixel(dx, dy);
    delay(50);  // Add a small delay to debounce and control speed
  }
}

void movePixel(int dx, int dy) {
  // Calculate new position
  int newX = constrain(pixelX + dx, 1, tft.width() - pixelSize - 1);
  int newY = constrain(pixelY + dy, 1, tft.height() - pixelSize - 1);
  
  // Only redraw if the position has changed
  if (newX != pixelX || newY != pixelY) {
    tft.startWrite();
    // Erase old pixel
    tft.writeFillRect(pixelX, pixelY, pixelSize, pixelSize, bgColor);
    
    // Update position
    pixelX = newX;
    pixelY = newY;
    
    // Draw new pixel
    tft.writeFillRect(pixelX, pixelY, pixelSize, pixelSize, pixelColor);
    tft.endWrite();
  }
}

void drawPixel() {
  tft.startWrite();
  tft.writeFillRect(pixelX, pixelY, pixelSize, pixelSize, pixelColor);
  tft.endWrite();
}