/*
  Description:
  - Read the potentiometer value on A0.
  - Divide the 0-1023 range into three regions.
    • Lower third (0-341) turns on led1, and the RGB LED shows red.
      The red channel’s PWM is mapped from the potentiometer reading (0->0, 341->255).
    • Middle third (342-682) turns on led2, and the RGB LED shows green.
      The green PWM is mapped from 342 (0) to 682 (255).
    • Upper third (683-1023) turns on led3, and the RGB LED shows blue.
      The blue PWM is mapped from 683 (0) to 1023 (255).
  - All other channels are turned off in each region.
*/

const int potPin = A0;    // Potentiometer signal pin
// Single color LED pins
const int led1Pin = 2;
const int led2Pin = 3;
const int led3Pin = 4;
// RGB LED pins (PWM capable)
const int redPin   = 5;
const int greenPin = 6;
const int bluePin  = 7;

void setup() {
  // Set LED pins as outputs.
  pinMode(led1Pin, OUTPUT);
  pinMode(led2Pin, OUTPUT);
  pinMode(led3Pin, OUTPUT);
  
  pinMode(redPin, OUTPUT);
  pinMode(greenPin, OUTPUT);
  pinMode(bluePin, OUTPUT);
  
  // Initialization: all LEDs off.
  digitalWrite(led1Pin, LOW);
  digitalWrite(led2Pin, LOW);
  digitalWrite(led3Pin, LOW);
  
  analogWrite(redPin, 0);
  analogWrite(greenPin, 0);
  analogWrite(bluePin, 0);
}

void loop() {
  int potValue = analogRead(potPin);  // Read the potentiometer value (0-1023)
  
  // Turn off all single-color LEDs first.
  digitalWrite(led1Pin, LOW);
  digitalWrite(led2Pin, LOW);
  digitalWrite(led3Pin, LOW);
  // Set all RGB channels to 0 initially.
  analogWrite(redPin, 0);
  analogWrite(greenPin, 0);
  analogWrite(bluePin, 0);
  
  if(potValue <= 341) {
    // Lower third: led1 indicator on, RGB shows red.
    digitalWrite(led1Pin, HIGH);
    int redBrightness = map(potValue, 0, 341, 0, 255);
    analogWrite(redPin, redBrightness);
  }
  else if(potValue <= 682) {
    // Middle third: led2 indicator on, RGB shows green.
    digitalWrite(led2Pin, HIGH);
    int greenBrightness = map(potValue, 342, 682, 0, 255);
    analogWrite(greenPin, greenBrightness);
  }
  else { // potValue is between 683 and 1023.
    // Upper third: led3 indicator on, RGB shows blue.
    digitalWrite(led3Pin, HIGH);
    int blueBrightness = map(potValue, 683, 1023, 0, 255);
    analogWrite(bluePin, blueBrightness);
  }
  
  delay(10);  // Small delay for stability
}