#include <FastLED.h>

#define Serial Serial1
#define btn 7
#define LED_PIN 14
#define NUM_LEDS 32
#define BRIGHTNESS 255
#define LED_TYPE WS2812
#define COLOR_ORDER GRB
CRGB leds[NUM_LEDS];

int menu = 0;
int mode = 0;
bool dir = 0;

// timeout in 60 seconds
int timeOut = 60;

uint8_t hue = 255;
uint8_t val = 255;

uint8_t var = 0;
int clr = 0;
int divisor = 30;

unsigned long timer = 0;
unsigned long timeNow = 0;

void setup() {
  //delay(1000);
  Serial.begin(115200);
  pinMode(btn, INPUT_PULLUP);
  FastLED.addLeds<LED_TYPE, LED_PIN, COLOR_ORDER>(leds, NUM_LEDS).setCorrection(TypicalLEDStrip);
  FastLED.setBrightness(BRIGHTNESS);
  FastLED.clear();
  FastLED.show();
  Serial.println("Setup Complete");
}

void loop() {
  timer = millis();
  if (menu == 0) {
    modes();
    while (digitalRead(btn) == 0) {
      delay(1000);
      // Press and hold 2 seconds - enters colour options
      if (millis() - timer > 2000 && millis() - timer < 5000) {
        Serial.println("change color");
        menu = 1;
        fill_solid(leds, NUM_LEDS, CRGB(255, 0, 0));
        FastLED.show();
        timeNow = millis();
      }
      // press and hold 5 seconds - enters brightness option
      if (millis() - timer > 5000 && millis() - timer < 10000) {
        Serial.println("Change brightness");
        menu = 2;
        fill_solid(leds, NUM_LEDS, CRGB(0, 0, 255));
        FastLED.show();
        timeNow = millis();
      }
      // press and hole 10 seconds - enters mode select
      if (millis() - timer > 10000 && millis() - timer < 15000) {
        Serial.println("Change modes");
        menu = 3;
        fill_solid(leds, NUM_LEDS, CRGB(0, 255, 0));
        FastLED.show();
        timeNow = millis();
      }
      // press and hole 15 seconds - reset selection
      if (millis() - timer > 15000) {
        Serial.println("Reset menu");
        menu = 0;
        fill_solid(leds, NUM_LEDS, CRGB(0, 0, 0));
        FastLED.show();
        timer = millis();
      }
    }
  }

  // change color
  if (menu == 1) {
    if (digitalRead(btn) == 0) {
      hue++;
    }
    fill_solid(leds, NUM_LEDS, CHSV(hue, 255, 255));
    FastLED.show();
    delay(20);

    // timeout
    if (millis() - timeNow > timeOut*1000) {
      menu = 0;
      Serial.println("Timeout! going back to main menu");
      delay(1000);
    }
  }

  // change brightness
  if (menu == 2) {
    if (digitalRead(btn) == 0) {
      if (dir) val++;
      if (!dir) val--;
      if (val <= 0) dir = !dir;
      //Serial.println(val);
    }
    fill_solid(leds, NUM_LEDS, CHSV(hue, 255, val));
    FastLED.show();
    delay(20);

    // timeout
    if (millis() - timeNow > timeOut*1000) {
      menu = 0;
      Serial.println("Timeout! going back to main menu");
      delay(1000);
    }
  }

  // change modes
  if (menu == 3) {
    if (digitalRead(btn) == 0) {
      mode++;
      if (mode >= 4) mode = 0;
      delay(250);
    }

    modes();

    // timeout
    if (millis() - timeNow > timeOut*1000) {
      menu = 0;
      Serial.println("Timeout! going back to main menu");
      delay(1000);
    }
  }
}

void modes(){
  if(mode == 0){
    Serial.println("Mode : Solid");
    fill_solid(leds, NUM_LEDS, CHSV(hue, 255, val));
    FastLED.show();
    delay(100);
  }
  if(mode == 1){
    Serial.println("Mode : Flow");
    for (int j = 0; j < 256; j++) {
      for (int i = 0; i < NUM_LEDS; i++) {
        leds[i] = Scroll((i * 256 / NUM_LEDS + j) % 256);
      }
      if (digitalRead(btn) == 0) break;
      FastLED.show();
      delay(1);
    }
  }
  if(mode == 2){
    Serial.println("Mode : Breath");
    float breath = (exp(sin(millis() / 5000.0 * PI)) - 0.36787944) * 108.0;
    breath = map(breath, 0, 255, 16, val);
    FastLED.setBrightness(breath);
    fill_solid(leds, NUM_LEDS, CHSV(hue, 255, 255));
    //fill_rainbow(leds, NUM_LEDS, (var++ / divisor));
    if (clr == (255 * divisor)) {
      clr = 0;
    }
    FastLED.show();
    delay(5);
  }
  if(mode == 3){
    FastLED.setBrightness(BRIGHTNESS);
    Serial.println("Mode : Strobe");
    for(int i = 0; i < 10; i++) {
      fill_solid(leds, NUM_LEDS, CHSV(hue, 255, val));
      FastLED.show();
      delay(50);
      fill_solid(leds, NUM_LEDS, CHSV(0, 0, 0));
      FastLED.show();
      delay(50);
      if (digitalRead(btn) == 0) break;
    }
    for(int i = 0; i < 10; i++) {
      delay(100);
      if (digitalRead(btn) == 0) break;
    }
  }
}

CRGB Scroll(int pos) {
  CRGB color(0, 0, 0);
  if (pos < 85) {
    color.g = 0;
    color.r = ((float)pos / 85.0f) * 255.0f;
    color.b = 255 - color.r;
  } else if (pos < 170) {
    color.g = ((float)(pos - 85) / 85.0f) * 255.0f;
    color.r = 255 - color.g;
    color.b = 0;
  } else if (pos < 256) {
    color.b = ((float)(pos - 170) / 85.0f) * 255.0f;
    color.g = 255 - color.b;
    color.r = 1;
  }
  return color;
}