// use the FastLED library (someone's pre-written code)
#include <FastLED.h>

// set how many LEDs there are and the data pin.
const int numLeds = 30;
const int ledStripPin = 6;

// this creates an array to reference our LEDs
CRGB leds[numLeds];

void setup() {
  // tells the FastLED code e.g. what LEDs we are using, the data pin
  FastLED.addLeds<NEOPIXEL, ledStripPin>(leds, numLeds);

  // limit the strip's draw to 400mA at 5v
  FastLED.setMaxPowerInVoltsAndMilliamps(5, 400);

  // turns the brightness down (so my eyes don't hurt)
  FastLED.setBrightness(8);
  pinMode(2, INPUT_PULLUP);
}

void loop() {
   if (digitalRead(2) == LOW) {
    turnAllRainbow();
   } else {
    
   }
    delay(100);
  }

void turnAllRainbow() {
  for (int colourNum=0; colourNum<5; colourNum++) {
    for (int i=0; i<30; i++) {
      if (colourNum == 0){
        leds[i] = CRGB::Green;
      } else if (colourNum == 1){  
        leds[i] = CRGB::Blue;
      } else if (colourNum == 2){  
        leds[i] = CRGB::Red;
        } else if (colourNum == 3){  
        leds[i] = CRGB::Purple;
      } else if (colourNum == 4){  
        leds[i] = CRGB::White;
      }
    FastLED.show();
    delay(100);
    }
    // FastLED.show();
    // delay(1000);
  }
}