#include <FastLED.h>

// I simulate lighting efects on parking sensor lamp
// 3rd approach: rotating and changing palette

#define LED_PIN     8
#define NUM_LEDS    17
#define BRIGHTNESS  255
#define LED_TYPE    WS2812
#define COLOR_ORDER GRB
CRGB leds[NUM_LEDS];

#define UPDATES_PER_SECOND 100


CRGBPalette16 currentPalette;
TBlendType    currentBlending;

extern CRGBPalette16 myRedWhiteBluePalette;
extern const TProgmemPalette16 myRedWhiteBluePalette_p PROGMEM;


void setup() {
    delay( 3000 ); // power-up safety delay
    FastLED.addLeds<LED_TYPE, LED_PIN, COLOR_ORDER>(leds, NUM_LEDS);
    FastLED.setBrightness( BRIGHTNESS );

    currentPalette = RainbowColors_p;
    currentBlending = LINEARBLEND;

    for (int j = 10; j<255; j+=5) {
        FastLED.setBrightness( j );
        for (int i = 0; i< NUM_LEDS; i+=2) {
            leds[i] = CHSV(0,0,0);
            leds[i+1] = CHSV(255,0,255);
        }
        FastLED.show();
        FastLED.delay(200);
        for (int i = 0; i< NUM_LEDS; i+=2) {
            leds[i] = CHSV(0,0,255);
            leds[i+1] = CHSV(255,0,0);
        }
        FastLED.show();
        FastLED.delay(200);
    }
    delay(2000);
}


void loop() {
    static uint8_t startIndex = 0;
    startIndex = startIndex + 1; /* motion speed */

    uint8_t secondHand = (millis() / 1000) % 60;
    static uint8_t lastSecond = 99;

    if( lastSecond != secondHand) {
        lastSecond = secondHand;
        
        if (secondHand==5) {
            SetupWhitePalette();    currentBlending = NOBLEND;
        }
        if (secondHand==25) {
            SetupBlackAndWhiteStripedPalette();    currentBlending = NOBLEND;
        }
        if (secondHand==45) {
            SetupPurpleAndGreenPalette();    currentBlending = NOBLEND;
        }
    }

    FillLEDsFromPaletteColors( startIndex);

    FastLED.show();
    FastLED.delay(1000 / UPDATES_PER_SECOND);
}

void FillLEDsFromPaletteColors( uint8_t colorIndex)
{
    uint8_t brightness = 255;

    for( int i = 0; i < NUM_LEDS; i++) {
        leds[i] = ColorFromPalette( currentPalette, colorIndex, brightness, currentBlending);
        colorIndex += 3;
    }
}


// There are several different palettes of colors demonstrated here.
//
// FastLED provides several 'preset' palettes: RainbowColors_p, RainbowStripeColors_p,
// OceanColors_p, CloudColors_p, LavaColors_p, ForestColors_p, and PartyColors_p.
//
// Additionally, you can manually define your own color palettes, or you can write
// code that creates color palettes on the fly.  All are shown here.




// This function sets up a palette of black and white stripes,
// using code.  Since the palette is effectively an array of
// sixteen CRGB colors, the various fill_* functions can be used
// to set them up.
void SetupBlackAndWhiteStripedPalette() {
    // 'black out' all 16 palette entries...
    fill_solid( currentPalette, 16, CRGB::Black);
    // and set every fourth one to white.
    for (int i=0 ; i< NUM_LEDS ; i+=4 ) {
        currentPalette[i] = CRGB::White;
    }
}

// WHITE test
void SetupWhitePalette() {
    fill_solid( currentPalette, 16, CRGB::White);
}

// This function sets up a palette of purple and green stripes.
void SetupPurpleAndGreenPalette()
{
    CRGB purple = CHSV( HUE_PURPLE, 255, 255);
    CRGB green  = CHSV( HUE_GREEN, 255, 255);
    CRGB black  = CRGB::Black;

    currentPalette = CRGBPalette16(
                                   green,  green,  black,  black,
                                   purple, purple, black,  black,
                                   green,  green,  black,  black,
                                   purple, purple, black,  black );
}


// This example shows how to set up a static color palette
// which is stored in PROGMEM (flash), which is almost always more
// plentiful than RAM.  A static PROGMEM palette like this
// takes up 64 bytes of flash.
const TProgmemPalette16 myRedWhiteBluePalette_p PROGMEM =
{
    CRGB::Red,
    CRGB::Gray, // 'white' is too bright compared to red and blue
    CRGB::Blue,
    CRGB::Black,

    CRGB::Red,
    CRGB::Gray,
    CRGB::Blue,
    CRGB::Black,

    CRGB::Red,
    CRGB::Red,
    CRGB::Gray,
    CRGB::Gray,
    CRGB::Blue,
    CRGB::Blue,
    CRGB::Black,
    CRGB::Black
};



// Additional notes on FastLED compact palettes:
//
// Normally, in computer graphics, the palette (or "color lookup table")
// has 256 entries, each containing a specific 24-bit RGB color.  You can then
// index into the color palette using a simple 8-bit (one byte) value.
// A 256-entry color palette takes up 768 bytes of RAM, which on Arduino
// is quite possibly "too many" bytes.
//
// FastLED does offer traditional 256-element palettes, for setups that
// can afford the 768-byte cost in RAM.
//
// However, FastLED also offers a compact alternative.  FastLED offers
// palettes that store 16 distinct entries, but can be accessed AS IF
// they actually have 256 entries; this is accomplished by interpolating
// between the 16 explicit entries to create fifteen intermediate palette
// entries between each pair.
//
// So for example, if you set the first two explicit entries of a compact
// palette to Green (0,255,0) and Blue (0,0,255), and then retrieved
// the first sixteen entries from the virtual palette (of 256), you'd get
// Green, followed by a smooth gradient from green-to-blue, and then Blue.