// RGB to CMYK conversion Arduino code
// Input format over Serial: R,G,B (e.g. 255,100,0)

void setup() {
  Serial.begin(9600);
  Serial.println("Send RGB values like: 255,100,0");
}

void loop() {
  if (Serial.available()) {
    String input = Serial.readStringUntil('\n');
    input.trim();

    // Parse RGB values from input
    int r = -1, g = -1, b = -1;
    sscanf(input.c_str(), "%d,%d,%d", &r, &g, &b);

    if (r >= 0 && g >= 0 && b >= 0 && r <= 255 && g <= 255 && b <= 255) {
      // Convert to CMYK
      float c, m, y, k;
      rgbToCmyk(r, g, b, &c, &m, &y, &k);

      Serial.println("CMYK Output:");
      Serial.print("C: "); Serial.print(c, 1); Serial.print("%, ");
      Serial.print("M: "); Serial.print(m, 1); Serial.print("%, ");
      Serial.print("Y: "); Serial.print(y, 1); Serial.print("%, ");
      Serial.print("K: "); Serial.print(k, 1); Serial.println("%");
    } else {
      Serial.println("Invalid input. Use format R,G,B (0-255 each).");
    }
  }
}

// Function to convert RGB to CMYK
void rgbToCmyk(int r, int g, int b, float* c, float* m, float* y, float* k) {
  float rf = r / 255.0;
  float gf = g / 255.0;
  float bf = b / 255.0;

  *k = 1.0 - max(max(rf, gf), bf);

  if (*k == 1.0) {
    *c = *m = *y = 0;
  } else {
    *c = (1.0 - rf - *k) / (1.0 - *k);
    *m = (1.0 - gf - *k) / (1.0 - *k);
    *y = (1.0 - bf - *k) / (1.0 - *k);
  }

  // Convert to percentage
  *c *= 100.0;
  *m *= 100.0;
  *y *= 100.0;
  *k *= 100.0;
}