#include "FastLED.h"
#include "Wire.h"
#include "Adafruit_GFX.h"
#include "Adafruit_SSD1306.h"
#include "Encoder.h"

#define LED_STRIP_PIN 6
#define OLED_RESET 7
Adafruit_SSD1306 display(OLED_RESET);
#define ROTARY_ENCODER_PIN_A 2
#define ROTARY_ENCODER_PIN_B 3
#define BUTTON_PIN 12
Encoder myEncoder(ROTARY_ENCODER_PIN_A, ROTARY_ENCODER_PIN_B);
long lastEncoderValue;
unsigned long timerSetting = 0;
unsigned long timerStartTime = 0;
bool timerActive = false;

#define NUM_LEDS 8
#define LED_TYPE WS2812B
#define COLOR_ORDER GRB
CRGB leds[NUM_LEDS];

void setup() {
  pinMode(LED_STRIP_PIN, OUTPUT);
  display.begin(SSD1306_SWITCHCAPVCC, 0x3C);
  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(WHITE);
  pinMode(BUTTON_PIN, INPUT_PULLUP);
  lastEncoderValue = myEncoder.read();
  FastLED.addLeds<LED_TYPE, LED_STRIP_PIN, COLOR_ORDER>(leds, NUM_LEDS).setCorrection(TypicalLEDStrip);
}

void loop() {
  long encoderValue = myEncoder.read();
  bool buttonPressed = digitalRead(BUTTON_PIN) == LOW;

  if (encoderValue != lastEncoderValue) {
    timerSetting += (encoderValue - lastEncoderValue) * 1000;
    if (timerSetting < 0) {
      timerSetting = 0;
    }
    timerActive = true;
    timerStartTime = millis();
    lastEncoderValue = encoderValue;
  }

  if (buttonPressed) {
    while (digitalRead(BUTTON_PIN) == LOW) {
      delay(10);
    }
    resetTimer();
  }

  updateLEDs();
  updateDisplay();
}

void resetTimer() {
  timerSetting = 0;
  timerActive = false;
  fill_solid(leds, NUM_LEDS, CRGB::Black);
  FastLED.show();
}

void updateLEDs() {
  if (timerActive) {
    unsigned long elapsedTime = millis() - timerStartTime;
    if (elapsedTime >= timerSetting) {
      timerActive = false;
    } else {
      int percentage = 100 - ((millis() - timerStartTime) * 100 / timerSetting);
      int numLitLEDs = map(percentage, 0, 100, 1, NUM_LEDS);
      int brightness = map(percentage, 0, 100, 40, 55);

      CRGB color;
      if (percentage >= 70) {
        color = CRGB::Green;
      } else if (percentage >= 30) {
        color = CRGB::Yellow;
      } else if (percentage >= 10) {
        color = CRGB::Orange;
      } else {
        color = CRGB::Red;
      }

      for (int i = 0; i < NUM_LEDS; i++) {
        if (i < numLitLEDs) {
          int ledBrightness = map(i, 0, NUM_LEDS - 1, brightness, 255);
          leds[i] = color;
          leds[i].fadeToBlackBy(255 - ledBrightness);
        } else {
          leds[i] = CRGB::Black;
        }
      }

      FastLED.show();
    }
  }
}

void updateDisplay() {
  display.clearDisplay();
  display.setCursor(0, 0);
  if (timerActive) {
    int percentage = 100 - ((millis() - timerStartTime) * 100 / timerSetting);
    display.print("Timer: ");
    display.print(percentage);
    display.print("%");
  } else {
    display.print("Timer: --");
  }
  display.display();
}