#include <FastLED.h>
#define NUM_STRIPS 4
#define LEDS_PER_STRIP 25
#define TOTAL_LEDS (NUM_STRIPS * LEDS_PER_STRIP)
#define DATA_LED_PIN 13
#define DATA_POTSPEED_PIN 12
#define DATA_POTLEN_PIN 14

CRGB leds[TOTAL_LEDS];

void setup() {
  FastLED.addLeds<NEOPIXEL, DATA_LED_PIN>(leds, TOTAL_LEDS);
  pinMode(DATA_POTSPEED_PIN, INPUT);
  pinMode(DATA_POTLEN_PIN, INPUT);
  Serial.begin(115200);
  Serial.println("Start");
}

void loop() {
  int pot = map(analogRead(DATA_POTSPEED_PIN), 0, 4095, 100, 5); // Speed control
  int len = map(analogRead(DATA_POTLEN_PIN), 0, 4095, 5, 50);    // Length control

  static int position = 0; // Static variable to keep track of position

  updateLEDs(position, len); // Update LEDs in a continuous loop
  position = (position + 1) % TOTAL_LEDS;

  delay(pot); // Delay for smooth animation
}

void updateLEDs(int position, int len) {
  // Calculate start and end points for the lit section with wrap-around
  for (int i = 0; i < TOTAL_LEDS; i++) {
    int distance = abs(i - position);
    if (distance > TOTAL_LEDS / 2) {
      distance = TOTAL_LEDS - distance; // Wrap around for continuous effect
    }

    if (distance <= len) {
      byte fadeAmount = map(distance, 0, len, 0, 255); // Fade amount calculation
      leds[i] = CRGB::Blue;
      leds[i].fadeToBlackBy(fadeAmount);
    } else {
      leds[i] = CRGB::Black;
    }
  }

  FastLED.show();
}