//LDRControlRandomFlashFadeNeopixel.INO
// Todd Andersen
// 09-FEB-17

//Random Flash animation for Neopixel Ring Bangle Bracelet
//by Dano Wall and Becky Stern for Adafruit Industries
//based on the Sparkle Skirt, minus the accelerometer
// https://learn.adafruit.com/neopixel-ring-bangle-bracelet/code

#include <Adafruit_NeoPixel.h>
#define PIXELS 1
#define PIN 2

const int LRDPin = A0; // Sensor pin = LRD
int sensorValue = 0;  // variable to store the value coming from the sensor
int ledPin = 13;
const int threshold = 500;

int stepMin = 5; // Smaller = Fewer and Larger = Greater
int stepsMax = 20; // Smaller = Fewer and Larger = Greater 
int steps (random(stepMin, stepsMax)); // Set pseudorandom step fade in / out range

int twinkMin = 5; // Smaller = Shorter and Larger = Longer
int twinkMax = 15; // Smaller = Shorter and Larger = Longer
int twinkle (random(twinkMin, twinkMax)); // Set pseudorandom twinkle time

int pixelMin = 1; // Smaller = Less and Larger = More
int pixelMax = 4; // Smaller = Less and Larger = More
int pixelCount (random(pixelMin, pixelMax)); // Set pseudorandom twinkling number of pixels

// Parameter 1 = number of pixels (PIXELS)
// Parameter 2 = pin number (PIN, most are valid)
// Parameter 3 = pixel type flags, add together as needed:
//   NEO_GRB     Pixels are wired for GRB bitstream (most NeoPixel products)
//   NEO_RGB     Pixels are wired for RGB bitstream (v1 FLORA pixels, not v2)
//   NEO_KHZ400  400 KHz (classic 'v1' (not v2) FLORA pixels, WS2811 drivers)
//   NEO_KHZ800  800 KHz bitstream (most NeoPixel products w/WS2812 LEDs)

Adafruit_NeoPixel strip = Adafruit_NeoPixel(PIXELS, PIN, NEO_RGB);

// Here is where you can put in your favorite colors that will appear!
// just add new {nnn, nnn, nnn}, lines. They will be picked out randomly
//                          R   G   B       // Use NEO_RGB for NeoLEDs
uint8_t myColors[][3] = { {232, 100, 255},  // purple
                          {200, 200, 020},  // yellow 
                          {030, 200, 200},  // blue
                          {255, 010, 100},  // off-red, TJA, 08-FEB-16
                          };
                               
// don't edit the line below
#define FAVCOLORS sizeof(myColors) / 3

void setup() {
  strip.begin();
  strip.setBrightness(100); // Range = 000 through 100, 40 = Default, 
  strip.show(); // Initialize all pixels to 'off'
}

void loop() {
  int sensorValue = analogRead (LRDPin); // Read the value of the LDR

  // LED on Nano Pin 13 as threashold indicator when OFF
  if ((sensorValue) <= (threshold)){
    digitalWrite(ledPin, HIGH);
  }         
  else{
    digitalWrite(ledPin, LOW);
  }

  if ((sensorValue) > (threshold)){
    return;
  }
               
flashRandom:(twinkle, pixelCount); // First number = 'Wait' delay, Smaller = Shorter twinkle
flashRandom (twinkle, pixelCount); // Second number = Number of neopixels to light at one time
flashRandom (twinkle, pixelCount);
}

void flashRandom(int wait, uint8_t howmany) {
  for(uint16_t i=0; i<howmany; i++) {    
    // pick a random favorite color!
    int c = random(FAVCOLORS);
    int red = myColors[c][0];
    int green = myColors[c][1];
    int blue = myColors[c][2]; 
 
    // get a random pixel from the list
    int j = random(strip.numPixels());
    
    // now we will 'fade in' steps
    for (int x=0; x < steps; x++) {
      int r = red * (x+1); r /= steps;
      int g = green * (x+1); g /= steps;
      int b = blue * (x+1); b /= steps;
        
      strip.setPixelColor(j, strip.Color(r, g, b));
      strip.show();
      delay(wait);
    }
    
    // & 'fade out' steps
    for (int x=5; x >= 0; x--) {
      int r = red * x; r /= steps;
      int g = green * x; g /= steps;
      int b = blue * x; b /= steps;

    // LEDs will be off when done (they are faded to 0)
    strip.setPixelColor(j, strip.Color(r, g, b));
    strip.show();
    delay(wait);
    }
  }
}