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

#define TFT_CS 10
#define TFT_DC 9
#define TFT_RST -1

Adafruit_ILI9341 tft = Adafruit_ILI9341(TFT_CS, TFT_DC, TFT_RST);

int maxSquaresX;
int maxSquaresY;
int squareSizeX;
int squareSizeY;
uint16_t rainbowColors[] = {ILI9341_RED, ILI9341_ORANGE, ILI9341_YELLOW, ILI9341_GREEN,
                               ILI9341_BLUE, tft.color565(75,0,130), tft.color565(238,130,238)};

void setup() {
  // Initialize TFT display
  tft.begin();

  // Set the color mode to use RGB values
  tft.setRotation(3);  // Adjust the rotation if needed

  // Get the dimensions of the TFT screen
  int screenWidth = tft.width();
  int screenHeight = tft.height();

  // Calculate the maximum number of squares in both dimensions
  maxSquaresX = screenWidth / 20;  // Adjust the divisor as needed
  maxSquaresY = screenHeight / 20; // Adjust the divisor as needed

  // Draw the big square
  tft.fillScreen(ILI9341_WHITE);
  tft.drawRect(0, 0, screenWidth, screenHeight, ILI9341_BLACK);

  // Draw and fill the small squares with rainbow colors
  squareSizeX = screenWidth / maxSquaresX;
  squareSizeY = screenHeight / maxSquaresY;

  for (int i = 0; i < maxSquaresY; i++) {
    for (int j = 0; j < maxSquaresX; j++) {
      int x = j * squareSizeX;
      int y = i * squareSizeY;
      tft.fillRect(x, y, squareSizeX, squareSizeY, rainbowColors[(i * maxSquaresX + j) % 7]);
    }
  }

  // Print the total number of squares to the serial monitor
  Serial.begin(9600);
}

void loop() {
  // Gradually shift the colors
  for (int shift = 0; shift < 7; shift++) {
    for (int i = 0; i < maxSquaresY; i++) {
      for (int j = 0; j < maxSquaresX; j++) {
        int x = j * squareSizeX;
        int y = i * squareSizeY;
        tft.fillRect(x, y, squareSizeX, squareSizeY, rainbowColors[((i * maxSquaresX + j) + shift) % 7]);
      }
    }
    delay(500);  // Adjust the delay as needed for the desired animation speed
  }
}