FastLED - CRGBSet attempt

// FastLED experiment with Gemini 2.5
// Uses 8 pixel strand with CRGBSet to control two sections
// 4/7/2025

#include <FastLED.h>

// -- Configuration --
#define NUM_LEDS 8        // Total number of LEDs in the strip
#define DATA_PIN 6        // Arduino pin connected to the Neopixel data line
#define LED_TYPE WS2812B  // Type of LED strip (WS2811, WS2812B, etc.)
#define COLOR_ORDER GRB   // Color order for the LED strip (GRB, RGB, etc.)
#define BRIGHTNESS 60     // Set initial brightness (0-255). Start low!

// -- Constants for Effects --
// Blinking Section (LEDs 0-1)
const int BLINK_INTERVAL = 3000;          // milliseconds for first two LEDs

// Effect Section (LEDs 2-7) - Slower, Longer Blinks
const uint8_t TURN_ON_CHANCE = 3;        // Chance (out of 256) per frame for an OFF LED to turn ON. LOW value = infrequent blinks.
const unsigned long MIN_ON_TIME = 800;   // Minimum time (ms) an LED stays ON
const unsigned long MAX_ON_TIME = 2500;  // Maximum time (ms) an LED stays ON

// -- Global Variables --
CRGB leds[NUM_LEDS];      // Array to hold LED color data

// State for LEDs 2-7
struct EffectLedState {
  bool isOn = false;
  unsigned long turnOffTime = 0;
  CRGB color = CRGB::Black;
};
// Create state array only for the effect LEDs (indices 2-7)
// Map physical index (2-7) to state index (0-5)
EffectLedState effectLedStates[NUM_LEDS - 2]; // Size 6 for 6 LEDs

// Timing for blinking section (LEDs 0-1)
unsigned long lastBlinkTime = 0;
bool blinkState = false;       // Current state: true = ON (Red), false = OFF (Black)

// -- Setup Function --
void setup() {
  Serial.begin(9600);
  delay(2000); // Give serial time to connect
  Serial.println("\n\nFastLED: Slow/Long Random Blinks");

  randomSeed(analogRead(0)); // Seed random number generator

  FastLED.addLeds<LED_TYPE, DATA_PIN, COLOR_ORDER>(leds, NUM_LEDS)
         .setCorrection(TypicalLEDStrip);
  FastLED.setBrightness(BRIGHTNESS);
  FastLED.clear(); // Initialize all LEDs to off
  FastLED.show();
  delay(50);
  Serial.println("Setup complete. Starting loop...");
}

// -- Main Loop --
void loop() {
  updateBlinkingSection();     // Update state for LEDs 0, 1
  updateSlowRandomBlinkSection(); // Update state for LEDs 2-7

  // Send the combined state of the 'leds' array to the strip
  FastLED.show();

  // Keep delay for overall frame rate control
  FastLED.delay(16); // Roughly 60 frames per second
}

// -- Update Functions --

// Function to handle the first two LEDs (blinking red) - UNCHANGED
void updateBlinkingSection() {
  unsigned long currentTime = millis();
  if (currentTime - lastBlinkTime >= BLINK_INTERVAL) {
    lastBlinkTime = currentTime;
    blinkState = !blinkState;
  }
  if (blinkState) {
    leds[0] = CRGB::Red;
    leds[1] = CRGB::Red;
  } else {
    leds[0] = CRGB::Black;
    leds[1] = CRGB::Black;
  }
}

// Function to handle LEDs 2-7 (slow, long random blinking colors) - NEW LOGIC
void updateSlowRandomBlinkSection() {
  unsigned long currentTime = millis();

  // Loop through effect section LEDs (indices 2 to NUM_LEDS-1)
  for (int i = 2; i < NUM_LEDS; i++) {
    int stateIndex = i - 2; // Map LED index (2-7) to state array index (0-5)

    // --- Check LED state ---
    if (effectLedStates[stateIndex].isOn) {
      // --- LED is currently ON ---
      // Check if its time to turn OFF
      if (currentTime >= effectLedStates[stateIndex].turnOffTime) {
         effectLedStates[stateIndex].isOn = false; // Update state
         leds[i] = CRGB::Black;                   // Set physical LED off
         effectLedStates[stateIndex].color = CRGB::Black; // Clear stored color
      } else {
         // Still ON - ensure the physical LED has the correct color
         // (This handles cases where it might have been accidentally turned off)
         leds[i] = effectLedStates[stateIndex].color;
      }

    } else {
      // --- LED is currently OFF ---
      // Give it a very small chance to turn ON
      if (random8() < TURN_ON_CHANCE) {
          // Calculate ON duration
          unsigned long onDuration = random(MIN_ON_TIME, MAX_ON_TIME + 1); // random() excludes upper bound

          // Update state
          effectLedStates[stateIndex].isOn = true;
          effectLedStates[stateIndex].turnOffTime = currentTime + onDuration;
          effectLedStates[stateIndex].color = CHSV(random8(), 220, 255); // New random color (slightly less saturated)

          // Set physical LED ON
          leds[i] = effectLedStates[stateIndex].color;
      }
       // else: LED remains OFF (leds[i] should be Black)
    }
  } // End loop through effect LEDs
}