// Pin definitions for single-color LEDs
const int led1Pin = 2;
const int led2Pin = 3;
const int led3Pin = 4;

// Pin definitions for RGB LEDs
const int rgb1RedPin = 5;
const int rgb1GreenPin = 6;
const int rgb1BluePin = 7;
const int rgb2RedPin = 8;
const int rgb2GreenPin = 9;
const int rgb2BluePin = 10;
const int rgb3RedPin = 11;
const int rgb3GreenPin = 12;
const int rgb3BluePin = 13;

// Pin definition for push button
const int btnPin = 22;

// Variables for tracking the mode and timing
int currentMode = 0;  // 0: Off (initial), 1-4: Modes 1-4
unsigned long lastButtonPressTime = 0;
const unsigned long buttonDebounceDelay = 50;  // 50ms debounce
const unsigned long modeChangeThreshold = 2000;  // 2 seconds minimum per mode

// Variables for button state
int buttonState = HIGH;  // Initial state (not pressed)
int lastButtonState = HIGH;
unsigned long lastDebounceTime = 0;

// Variables for rainbow effect
int rainbowPhase = 0;
unsigned long lastRainbowUpdate = 0;
const unsigned long rainbowUpdateInterval = 10;  // Control rainbow animation speed

// Function to turn off all LEDs
void turnOffAllLEDs() {
  // Turn off single-color LEDs
  digitalWrite(led1Pin, LOW);
  digitalWrite(led2Pin, LOW);
  digitalWrite(led3Pin, LOW);
  
  // Turn off RGB LEDs
  analogWrite(rgb1RedPin, 0);
  analogWrite(rgb1GreenPin, 0);
  analogWrite(rgb1BluePin, 0);
  analogWrite(rgb2RedPin, 0);
  analogWrite(rgb2GreenPin, 0);
  analogWrite(rgb2BluePin, 0);
  analogWrite(rgb3RedPin, 0);
  analogWrite(rgb3GreenPin, 0);
  analogWrite(rgb3BluePin, 0);
}

// Mode 1: RGB LEDs display red, green, and blue colors respectively
void mode1() {
  // Set indicator LED
  digitalWrite(led1Pin, HIGH);
  digitalWrite(led2Pin, LOW);
  digitalWrite(led3Pin, LOW);
  
  // Set RGB LEDs
  // RGB1 - Red
  analogWrite(rgb1RedPin, 255);
  analogWrite(rgb1GreenPin, 0);
  analogWrite(rgb1BluePin, 0);
  
  // RGB2 - Green
  analogWrite(rgb2RedPin, 0);
  analogWrite(rgb2GreenPin, 255);
  analogWrite(rgb2BluePin, 0);
  
  // RGB3 - Blue
  analogWrite(rgb3RedPin, 0);
  analogWrite(rgb3GreenPin, 0);
  analogWrite(rgb3BluePin, 255);
}

// Mode 2: RGB LEDs display a rainbow effect (yellow, cyan, purple)
void mode2() {
  // Set indicator LED
  digitalWrite(led1Pin, LOW);
  digitalWrite(led2Pin, HIGH);
  digitalWrite(led3Pin, LOW);
  
  // Update rainbow effect at specified interval
  unsigned long currentMillis = millis();
  if (currentMillis - lastRainbowUpdate >= rainbowUpdateInterval) {
    lastRainbowUpdate = currentMillis;
    
    // Calculate the three color positions in the cycle
    int pos1 = rainbowPhase % 600;
    int pos2 = (rainbowPhase + 200) % 600;  // Offset by 1/3 of the cycle
    int pos3 = (rainbowPhase + 400) % 600;  // Offset by 2/3 of the cycle
    
    // Set the colors for each RGB LED
    setRainbowColor(rgb1RedPin, rgb1GreenPin, rgb1BluePin, pos1);
    setRainbowColor(rgb2RedPin, rgb2GreenPin, rgb2BluePin, pos2);
    setRainbowColor(rgb3RedPin, rgb3GreenPin, rgb3BluePin, pos3);
    
    // Increment phase for animation
    rainbowPhase = (rainbowPhase + 1) % 600;
  }
}

// Helper function for rainbow effect
void setRainbowColor(int redPin, int greenPin, int bluePin, int position) {
  // This function cycles through Yellow -> Cyan -> Purple -> Yellow
  // based on the position in a 0-599 cycle
  
  int red, green, blue;
  
  if (position < 200) {
    // Yellow to Cyan transition
    float ratio = position / 200.0;
    red = 255 * (1 - ratio);
    green = 255;
    blue = 255 * ratio;
  } else if (position < 400) {
    // Cyan to Purple transition
    float ratio = (position - 200) / 200.0;
    red = 255 * ratio;
    green = 255 * (1 - ratio);
    blue = 255;
  } else {
    // Purple to Yellow transition
    float ratio = (position - 400) / 200.0;
    red = 255;
    green = 255 * ratio;
    blue = 255 * (1 - ratio);
  }
  
  analogWrite(redPin, red);
  analogWrite(greenPin, green);
  analogWrite(bluePin, blue);
}

// Mode 3: RGB LEDs display a warm white color
void mode3() {
  // Set indicator LED
  digitalWrite(led1Pin, LOW);
  digitalWrite(led2Pin, LOW);
  digitalWrite(led3Pin, HIGH);
  
  // Set all RGB LEDs to warm white (equal R, G, B values as specified)
  analogWrite(rgb1RedPin, 255);
  analogWrite(rgb1GreenPin, 255);
  analogWrite(rgb1BluePin, 255);
  
  analogWrite(rgb2RedPin, 255);
  analogWrite(rgb2GreenPin, 255);
  analogWrite(rgb2BluePin, 255);
  
  analogWrite(rgb3RedPin, 255);
  analogWrite(rgb3GreenPin, 255);
  analogWrite(rgb3BluePin, 255);
}

// Mode 4: All LEDs turn off
void mode4() {
  turnOffAllLEDs();
}

void setup() {
  // Initialize serial communication for debugging
  Serial.begin(9600);
  
  // Initialize single-color LED pins as outputs
  pinMode(led1Pin, OUTPUT);
  pinMode(led2Pin, OUTPUT);
  pinMode(led3Pin, OUTPUT);
  
  // Initialize RGB LED pins as outputs
  pinMode(rgb1RedPin, OUTPUT);
  pinMode(rgb1GreenPin, OUTPUT);
  pinMode(rgb1BluePin, OUTPUT);
  pinMode(rgb2RedPin, OUTPUT);
  pinMode(rgb2GreenPin, OUTPUT);
  pinMode(rgb2BluePin, OUTPUT);
  pinMode(rgb3RedPin, OUTPUT);
  pinMode(rgb3GreenPin, OUTPUT);
  pinMode(rgb3BluePin, OUTPUT);
  
  // Initialize button pin as input with pull-up resistor
  pinMode(btnPin, INPUT_PULLUP);
  
  // Turn off all LEDs initially
  turnOffAllLEDs();
}

void loop() {
  // Button debouncing logic
  int reading = digitalRead(btnPin);
  
  if (reading != lastButtonState) {
    lastDebounceTime = millis();
  }
  
  if ((millis() - lastDebounceTime) > buttonDebounceDelay) {
    if (reading != buttonState) {
      buttonState = reading;
      
      // If the button is pressed (LOW due to pull-up resistor)
      if (buttonState == LOW) {
        // Check if enough time has passed since the last mode change
        if (millis() - lastButtonPressTime >= modeChangeThreshold) {
          // Cycle to the next mode
          currentMode = (currentMode % 4) + 1;  // Cycle from 1 to 4
          lastButtonPressTime = millis();
          
          // Debug output
          Serial.print("Mode changed to: ");
          Serial.println(currentMode);
        }
      }
    }
  }
  
  lastButtonState = reading;
  
  // Execute the current mode
  switch (currentMode) {
    case 1:
      mode1();
      break;
    case 2:
      mode2();
      break;
    case 3:
      mode3();
      break;
    case 4:
      mode4();
      break;
    default:
      // Initial state or invalid mode, turn everything off
      turnOffAllLEDs();
      break;
  }
  
  // Small delay for stability
  delay(5);
}