int PWM = 0;
int R = 1;
int G = 2;
int B = 3;
int START = 4;
int RGBVAR = 5;

int toff = 5;
int pwm = 0;
int pwm_set = 0;
int pwm_low = 50;
int pwm_mid = 125;
int pwm_max = 255;
int start = 0;
int rgbvar = 0;
int varcol = -1;
int col_set = 0;

void setup()
{
   pinMode(START, INPUT);
   pinMode(RGBVAR, INPUT);
   pinMode(R, OUTPUT);
   pinMode(G, OUTPUT);
   pinMode(B, OUTPUT);
   pinMode(PWM, OUTPUT);
}

void loop(){
  while(1){
    rgbvar = digitalRead(RGBVAR); //se RGBVAR cambio colore 6 combinazioni
    if(rgbvar == HIGH){
      varcol = varcol + 1;
      if(varcol > 20){
        varcol = 0;
      }
      switch(varcol){
        case(0):
          col_set = 0;
          pwm = pwm_max;
          analogWrite(PWM, pwm); digitalWrite(R, HIGH); digitalWrite(G, LOW);   digitalWrite(B, LOW);
          break;
        case(1):
          col_set = 1;
          pwm = pwm_max;
          analogWrite(PWM, pwm); digitalWrite(R, LOW);  digitalWrite(G, HIGH);  digitalWrite(B, LOW);
          break;
        case(2):
          col_set = 2;
          pwm = pwm_max;
          analogWrite(PWM, pwm); digitalWrite(R, LOW);  digitalWrite(G, LOW);   digitalWrite(B, HIGH);
          break;
        case(3):
          col_set = 3;
          pwm = pwm_max;
          analogWrite(PWM, pwm); digitalWrite(R, HIGH); digitalWrite(G, HIGH);  digitalWrite(B, LOW);
          break;
        case(4):
          col_set = 4;
          pwm = pwm_max;
          analogWrite(PWM, pwm); digitalWrite(R, HIGH); digitalWrite(G, LOW);   digitalWrite(B, HIGH);
          break;
        case(5):
          col_set = 5;
          pwm = pwm_max;
          analogWrite(PWM, pwm); digitalWrite(R, LOW);  digitalWrite(G, HIGH);  digitalWrite(B, HIGH);
          break;
        case(6):
          col_set = 6;
          pwm = pwm_max;
          analogWrite(PWM, pwm); digitalWrite(R, HIGH); digitalWrite(G, HIGH);   digitalWrite(B, HIGH);
          break;
        case(7):
          col_set = 0;
          pwm = pwm_mid;
          analogWrite(PWM, pwm); digitalWrite(R, HIGH); digitalWrite(G, LOW);   digitalWrite(B, LOW);
          break;
        case(8):
          col_set = 1;
          pwm = pwm_mid;
          analogWrite(PWM, pwm); digitalWrite(R, LOW);  digitalWrite(G, HIGH);  digitalWrite(B, LOW);
          break;
        case(9):
          col_set = 2;
          pwm = pwm_mid;
          analogWrite(PWM, pwm); digitalWrite(R, LOW);  digitalWrite(G, LOW);   digitalWrite(B, HIGH);
          break;
        case(10):
          col_set = 3;
          pwm = pwm_mid;
          analogWrite(PWM, pwm); digitalWrite(R, HIGH); digitalWrite(G, HIGH);  digitalWrite(B, LOW);
          break;
        case(11):
          col_set = 4;
          pwm = pwm_mid;
          analogWrite(PWM, pwm); digitalWrite(R, HIGH); digitalWrite(G, LOW);   digitalWrite(B, HIGH);
          break;
        case(12):
          col_set = 5;
          pwm = pwm_mid;
          analogWrite(PWM, pwm); digitalWrite(R, LOW);  digitalWrite(G, HIGH);  digitalWrite(B, HIGH);
          break;
        case(13):
          col_set = 6;
          pwm = pwm_mid;
          analogWrite(PWM, pwm); digitalWrite(R, HIGH); digitalWrite(G, HIGH);   digitalWrite(B, HIGH);
          break;
        case(14):
          col_set = 0;
          pwm = pwm_low;
          analogWrite(PWM, pwm); digitalWrite(R, HIGH); digitalWrite(G, LOW);   digitalWrite(B, LOW);
          break;
        case(15):
          col_set = 1;
          pwm = pwm_low;
          analogWrite(PWM, pwm); digitalWrite(R, LOW);  digitalWrite(G, HIGH);  digitalWrite(B, LOW);
          break;
        case(16):
          col_set = 2;
          pwm = pwm_low;
          analogWrite(PWM, pwm); digitalWrite(R, LOW);  digitalWrite(G, LOW);   digitalWrite(B, HIGH);
          break;
        case(17):
          col_set = 3;
          pwm = pwm_low;
          analogWrite(PWM, pwm); digitalWrite(R, HIGH); digitalWrite(G, HIGH);  digitalWrite(B, LOW);
          break;
        case(18):
          col_set = 4;
          pwm = pwm_low;
          analogWrite(PWM, pwm); digitalWrite(R, HIGH); digitalWrite(G, LOW);   digitalWrite(B, HIGH);
          break;
        case(19):
          col_set = 5;
          pwm = pwm_low;
          analogWrite(PWM, pwm); digitalWrite(R, LOW);  digitalWrite(G, HIGH);  digitalWrite(B, HIGH);
          break;
        case(20):
          col_set = 6;
          pwm = pwm_low;
          analogWrite(PWM, pwm); digitalWrite(R, HIGH); digitalWrite(G, HIGH);   digitalWrite(B, HIGH);
          break;
      }
      delay(500);
      analogWrite(PWM, 0);
      digitalWrite(R, LOW); digitalWrite(G, LOW);   digitalWrite(B, LOW);
    }
    start = digitalRead(START); 
    if(start == HIGH){ //se start(sensore capacitivo)
      RGB_VAR(col_set, pwm); // led accesi finchè il sensore non è più abilitato
      while(1){
        start = digitalRead(START);
        if(start == LOW){
          break;
        }
      }
      delay(250);
      break;
    }
  }
  pwm_set = pwm;
  while(1){
    RGB_VAR(col_set, pwm_set);
    pwm_set = pwm_set-1;
    if(pwm_set < 0){
      pwm_set = pwm;
      RGB_VAR(col_set, 0);
      break;
    }
  }
  analogWrite(PWM, 0);
  digitalWrite(R, LOW); digitalWrite(G, LOW);   digitalWrite(B, LOW);
}


void RGB_VAR(int valrgb, int valpwm){
  pwm_set = valpwm;
  switch(valrgb){
    case(0):
      digitalWrite(R, HIGH); digitalWrite(G, LOW);   digitalWrite(B, LOW);
    break;
    case(1):
      digitalWrite(R, LOW); digitalWrite(G, HIGH);   digitalWrite(B, LOW);
    break;
    case(2):
      digitalWrite(R, LOW); digitalWrite(G, LOW);   digitalWrite(B, HIGH);
    break;
    case(3):
      digitalWrite(R, HIGH); digitalWrite(G, HIGH);   digitalWrite(B, LOW);
    break;
    case(4):
      digitalWrite(R, HIGH); digitalWrite(G, LOW);   digitalWrite(B, HIGH);
    break;
    case(5):
      digitalWrite(R, LOW); digitalWrite(G, HIGH);   digitalWrite(B, HIGH);
    break;
    case(6):
      digitalWrite(R, HIGH); digitalWrite(G, HIGH);   digitalWrite(B, HIGH);
    break;
  }
  analogWrite(PWM, valpwm);
  delay(toff);
}