#include <Arduino.h>
  #include <driver/ledc.h>

  #define BUTTON_PIN 0
  #define POTENTIOMETER_PIN 4
  #define LED_RED_PIN 21
  #define LED_GREEN_PIN 19
  #define LED_BLUE_PIN 18

  const int PWM_FREQUENCY = 5000;
  const int PWM_RESOLUTION = 8;
  const int RED_CHANNEL = 0;
  const int GREEN_CHANNEL = 1;
  const int BLUE_CHANNEL = 2;

  void updateMode1();
  void updateMode2();
  void updateMode3();
  void updateMode4();

  bool lastButtonState = HIGH;
  int currentMode = 0;
  unsigned long lastModeChangeTime = 0;
  unsigned long lastColorChangeTime = 0;

  void setup()
  {

    pinMode(BUTTON_PIN, INPUT_PULLUP);
    pinMode(POTENTIOMETER_PIN, INPUT);

    ledcSetup(RED_CHANNEL, PWM_FREQUENCY, PWM_RESOLUTION);
    ledcSetup(GREEN_CHANNEL, PWM_FREQUENCY, PWM_RESOLUTION);
    ledcSetup(BLUE_CHANNEL, PWM_FREQUENCY, PWM_RESOLUTION);

    ledcAttachPin(LED_RED_PIN, RED_CHANNEL);
    ledcAttachPin(LED_GREEN_PIN, GREEN_CHANNEL);
    ledcAttachPin(LED_BLUE_PIN, BLUE_CHANNEL);

    Serial.begin(115200);
  }

  void loop()
  {
    bool currentButtonState = digitalRead(BUTTON_PIN);
    if (lastButtonState == HIGH && currentButtonState == LOW && millis() - lastModeChangeTime > 200)
    {
      currentMode = (currentMode + 1) % 4;
      lastModeChangeTime = millis();
    }
    lastButtonState = currentButtonState;

    switch (currentMode)
    {
    case 0:
      updateMode1();
      break;
    case 1:
      updateMode2();
      break;
    case 2:
      updateMode3();
      break;
    case 3:
      updateMode4();
      break;
    }

    delay(50);
  }

  void updateMode1()
  {
    int sensorValue = analogRead(POTENTIOMETER_PIN);
    int brightness = map(sensorValue, 0, 4095, 0, 255);

    ledcWrite(RED_CHANNEL, 255 - brightness);
    ledcWrite(GREEN_CHANNEL, 255 - brightness);
    ledcWrite(BLUE_CHANNEL, 255 - brightness);
  }

  void updateMode2()
  {

    int sensorValue = analogRead(POTENTIOMETER_PIN);
    int brightness = map(sensorValue, 0, 4095, 0, 255);

    ledcWrite(RED_CHANNEL, 255 - map(brightness, 0, 255, 0, 255));
    ledcWrite(GREEN_CHANNEL, 255 - map(brightness, 0, 255, 0, 153));
    ledcWrite(BLUE_CHANNEL, 255 - map(brightness, 0, 255, 0, 51));
  }

  void updateMode3() {
    int speedControl = map(analogRead(POTENTIOMETER_PIN), 0, 4095, 1, 10);
    static int colorPhase = 0;
    static int colorValue = 0;

    colorValue += speedControl;
    
    switch (colorPhase) {
      case 0:
        ledcWrite(RED_CHANNEL, 255 - colorValue);
        ledcWrite(GREEN_CHANNEL, 255 - (255 - colorValue));
        ledcWrite(BLUE_CHANNEL, 255);
        if (colorValue >= 255) {
          colorPhase = 1;
          colorValue = 0;
        }
        break;
      case 1:
        ledcWrite(RED_CHANNEL, 255);
        ledcWrite(GREEN_CHANNEL, 255 - colorValue);
        ledcWrite(BLUE_CHANNEL, 255 - (255 - colorValue));
        if (colorValue >= 255) {
          colorPhase = 2;
          colorValue = 0;
        }
        break;
      case 2:
        ledcWrite(RED_CHANNEL, 255 - (255 - colorValue));
        ledcWrite(GREEN_CHANNEL, 255);
        ledcWrite(BLUE_CHANNEL, 255 - colorValue);
        if (colorValue >= 255) {
          colorPhase = 0;
          colorValue = 0;
        }
        break;
    }

  }
  void updateMode4()
  {

    int sensorValue = analogRead(POTENTIOMETER_PIN);
    int brightness = map(sensorValue, 0, 4095, 0, 30);

    ledcWrite(RED_CHANNEL, 255 - map(brightness, 0, 30, 255, 255));
    ledcWrite(GREEN_CHANNEL, 255 - map(brightness, 0, 30,229, 178));
    ledcWrite(BLUE_CHANNEL, 255 - map(brightness, 0, 30, 204, 102));
  }