/************************************************
 SIMPLE 5 STEP PWM DIMMER
 Single Tap Only
************************************************/

#define PWM_PIN     9
#define BUTTON_PIN  2

#define LED1 6
#define LED2 5
#define LED3 4
#define LED4 3

int steps[5] = {50, 100, 180, 255, 0};
int currentStep = 4;   // Start OFF

int last_Step = 0;

bool buttonState;
bool lastButtonState = HIGH;
bool longPressHandled = false;

// ===== TIMER VARIABLES =====
unsigned long timerDuration = 15000;  // 15 seconds
unsigned long timerStartTime = 0;
bool timerRunning = false;

unsigned long pressStartTime = 0;
unsigned long lastReleaseTime = 0;

int tapCount = 0;

#define DOUBLE_TAP_TIME 500
#define HOLD_TIME       3000
#define DEBOUNCE        50

void setup() {

  Serial.begin(9600);

  pinMode(PWM_PIN, OUTPUT);
  pinMode(BUTTON_PIN, INPUT_PULLUP);

  pinMode(LED1, OUTPUT);
  pinMode(LED2, OUTPUT);
  pinMode(LED3, OUTPUT);
  pinMode(LED4, OUTPUT);

  analogWrite(PWM_PIN, 0);
  updateIndicators();
  last_Step = 0;

  Serial.println("System Booted - OFF");
}

void loop() {

  buttonState = digitalRead(BUTTON_PIN);

  // Button Pressed
  if (lastButtonState == HIGH && buttonState == LOW) {
    delay(DEBOUNCE);
    if (digitalRead(BUTTON_PIN) == LOW) {
      pressStartTime = millis();
      longPressHandled = false;   // reset for new press
      Serial.println("Pressed");
    }
  }

  // Button Released
  if (lastButtonState == LOW && buttonState == HIGH) {
    unsigned long pressDuration = millis() - pressStartTime;

    Serial.print("Press Duration: ");
    Serial.println(pressDuration);

    Serial.print("tapCount: ");
    Serial.println(tapCount);

    // Ignore very short noise presses
if (pressDuration > 100) {

  tapCount++;

  Serial.print("Valid Tap Count: ");
  Serial.println(tapCount);

  lastReleaseTime = millis();

} else {
  Serial.println("Ignored Noise Press");
}
  }
  
  
// ===== LONG PRESS 5s TO FORCE OFF =====
if (buttonState == LOW && currentStep != 4 && !longPressHandled) {

  if (millis() - pressStartTime >= 5000) {

    Serial.println("5s Long Press → FORCE OFF");

    currentStep = 4;
    analogWrite(PWM_PIN, 0);
    updateIndicators();
    timerRunning = false;
    Serial.println("Timer Stopped");

    longPressHandled = true;   // prevent repeat trigger
    tapCount = 0;

    delay(500);
  }
}

  // Check Tap Result
  if (tapCount > 0 && millis() - lastReleaseTime > DOUBLE_TAP_TIME) {

    // ===== DOUBLE TAP DETECTED =====
    // ===== DOUBLE TAP DETECTED =====
   if (tapCount == 2) {

    Serial.println("Double Tap Detected");

  if (currentStep == 4) {

    Serial.println("Waiting for 3s Hold...");

    unsigned long holdStart = millis();

    while (digitalRead(BUTTON_PIN) == LOW) {

      if (millis() - holdStart >= HOLD_TIME) {

  Serial.println("3s Hold Confirmed → STEP 1");

  currentStep = 0;
  updateIndicators();
   int target = steps[currentStep];

  if (target > last_Step) {
    for (int i = last_Step; i <= target; i++) {
      analogWrite(PWM_PIN, i);
      delay(4);
    }
  } else {
    for (int i = last_Step; i >= target; i--) {
      analogWrite(PWM_PIN, i);
      delay(4);
    }
  }

  last_Step = target;

  

  timerStartTime = millis();
timerRunning = true;
Serial.println("Timer Started: 5 Minutes");

  // IMPORTANT FIX
  longPressHandled = true;
  tapCount = 0;
  lastReleaseTime = 0;

  delay(300);
  return;
}
    }

    Serial.println("Hold Failed");
  }
}

    // ===== SINGLE TAP =====
    else if (tapCount == 1) {

      // Ignore single tap if OFF
      if (currentStep != 4) {
        nextStep();
      } else {
        Serial.println("OFF Mode - Single tap ignored");
      }
    }

    tapCount = 0;
  }

  lastButtonState = buttonState;

  // ===== TIMER CHECK =====
if (timerRunning && currentStep != 4) {

  if (millis() - timerStartTime >= timerDuration) {

    Serial.println("Timer Finished → Auto OFF");

    currentStep = 4;
    analogWrite(PWM_PIN, 0);
    updateIndicators();

    timerRunning = false;
  }
}
}


/************* STEP CONTROL *************/

void nextStep() {

  currentStep++;

  if (currentStep > 4) {
    currentStep = 0;
  }
  updateIndicators();
  int target = steps[currentStep];

  if (target > last_Step) {
    for (int i = last_Step; i <= target; i++) {
      analogWrite(PWM_PIN, i);
      delay(4);
    }
  } else {
    for (int i = last_Step; i >= target; i--) {
      analogWrite(PWM_PIN, i);
      delay(4);
    }
  }

  last_Step = target;

  

  if (currentStep != 4) {
  timerStartTime = millis();
  timerRunning = true;
  Serial.println("Timer Restarted: 5 Minutes");
}
}


/************* LED INDICATORS *************/

void updateIndicators() {

  digitalWrite(LED1, LOW);
  digitalWrite(LED2, LOW);
  digitalWrite(LED3, LOW);
  digitalWrite(LED4, LOW);

  if (currentStep == 0) digitalWrite(LED1, HIGH);
  if (currentStep == 1) digitalWrite(LED2, HIGH);
  if (currentStep == 2) digitalWrite(LED3, HIGH);
  if (currentStep == 3) digitalWrite(LED4, HIGH);
}