#include <LiquidCrystal_I2C.h>

LiquidCrystal_I2C lcd(0x27, 16, 2);

const int R_ledPin = 11;                    // LED
const int G_ledPin = 10;
const int B_ledPin = 9;

const int LED_R = 6;                        // 3LED
const int LED_G = 5;
const int LED_B = 3;

int ledStateR = LOW;                        // LED State
int ledStateG = HIGH;
int ledStateB = LOW;

unsigned long preMillisR = 0;               // millis State
unsigned long preMillisG = 0;
unsigned long preMillisB = 0;
unsigned long preMillisLED = 0;

int sw_Pin = 12;                            // button
int sw_LED = 13;

const long interval = 1000;

int count1;

void setup() {
  
  Serial.begin(115200);

  pinMode(sw_Pin, INPUT);
  pinMode(sw_LED, OUTPUT);
  
  pinMode(R_ledPin, OUTPUT);                // LED pin OUT
  pinMode(G_ledPin, OUTPUT);
  pinMode(B_ledPin, OUTPUT);

  pinMode(LED_R, OUTPUT);                    // LED pin OUT
  pinMode(LED_G, OUTPUT);
  pinMode(LED_B, OUTPUT);

  lcd.init();
  lcd.clear();
  lcd.backlight();
}


void loop() {
  unsigned long currentMillis = millis();    // millis

  if ( currentMillis %1000==0) {           // Time
    Serial.print(currentMillis);
    Serial.println("ms");
    //delay(1);
  }

  lcd.setCursor (5,0);                        // LCD 커서위치 지정
  lcd.print(currentMillis);              // 출력물
  lcd.setCursor (14,0);                        // LCD 커서위치 지정
  lcd.print("ms");                             // 출력물

  if (currentMillis - preMillisR >= interval * 2) {   // LED
    preMillisR = currentMillis;

    if (ledStateR == LOW) {
      ledStateR = HIGH;
    } else {
      ledStateR = LOW;
    }
    digitalWrite(R_ledPin, ledStateR);
  }
    
  if (currentMillis - preMillisG >= interval) {
    preMillisG = currentMillis;

    if (ledStateG == LOW) {
      ledStateG = HIGH;
    } else {
      ledStateG = LOW;
    }    
    digitalWrite(G_ledPin, ledStateG);
  }
    
  if (currentMillis - preMillisB >= interval / 2) {
    preMillisB = currentMillis;

    if (ledStateB == LOW) {
      ledStateB = HIGH;
    } else {
      ledStateB = LOW;
    }    
    digitalWrite(B_ledPin, ledStateB);
  }

  int btState = digitalRead(sw_Pin);                // button
  digitalWrite(sw_LED, btState);

  if (currentMillis - preMillisLED >= interval/3) {   // 3LED
    preMillisLED = currentMillis;
    showRGB(count1);
    count1++;
    if(count1 >= 768){count1=0;}
  }

}


void showRGB(int color)
{
  int R_Intensity;
  int G_Intensity;
  int B_Intensity;

  if (color <= 255)         
  {
    R_Intensity = 255 - color;    
    G_Intensity = color;        
    B_Intensity = 0;             
  }
  else if (color <= 511)     
  {
    R_Intensity = 0;                     
    G_Intensity = 255 - (color - 256); 
    B_Intensity = (color - 256);        
  }
  else 
  {
    R_Intensity = (color - 512);         
    G_Intensity = 0;                   
    B_Intensity = 255 - (color - 512);  
  }

  analogWrite(LED_R, R_Intensity);
  analogWrite(LED_G, G_Intensity);
  analogWrite(LED_B, B_Intensity);
}