// Advanced Automatic Water Dispenser with LED, Buzzer Alerts, and Blind Detection Beeps
// Features: LCD, Potentiometer refill control, Ultrasonic glass detection,
// Buzzer and 3-color LED status indicators (Green, Yellow, Red),
// Blind-friendly beeps for water level after dispensing

#include <LiquidCrystal.h>

#define TRIG_PIN 7
#define ECHO_PIN 6
#define POT_PIN A0
#define REFILL_BUTTON_PIN 8
#define GREEN_LED_PIN 9
#define YELLOW_LED_PIN 10
#define RED_LED_PIN A1      // Using analog pin as digital
#define BUZZER_PIN A2       // Tank status buzzer
#define BLIND_BUZZER_PIN A3 // New buzzer for blind beeps

LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

int waterLevelPercent = 100;
unsigned long dispenseStartTime = 0;
bool dispensing = false;
bool glassWasPresent = false;
bool waitingForGlassRemoval = false;
bool allowSensorUpdate = false;

void setup() {
  pinMode(TRIG_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);
  pinMode(REFILL_BUTTON_PIN, INPUT_PULLUP);
  pinMode(GREEN_LED_PIN, OUTPUT);
  pinMode(YELLOW_LED_PIN, OUTPUT);
  pinMode(RED_LED_PIN, OUTPUT);
  pinMode(BUZZER_PIN, OUTPUT);
  pinMode(BLIND_BUZZER_PIN, OUTPUT);

  lcd.begin(16, 2);
  lcd.print("Water Level:");
  delay(1000);

  int initialLevel = map(analogRead(POT_PIN), 0, 1023, 0, 100);
  waterLevelPercent = initialLevel;
  showWaterLevel(waterLevelPercent);
}

long readDistanceCM() {
  digitalWrite(TRIG_PIN, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);
  long duration = pulseIn(ECHO_PIN, HIGH);
  return duration * 0.034 / 2;
}

void updateIndicators(int level) {
  digitalWrite(GREEN_LED_PIN, level > 50);
  digitalWrite(YELLOW_LED_PIN, level <= 50 && level > 10);
  digitalWrite(RED_LED_PIN, level <= 10);

  if (level <= 0) {
    tone(BUZZER_PIN, 1000);
  } else {
    noTone(BUZZER_PIN);
  }
}

void showWaterLevel(int level) {
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Water Level: ");
  lcd.print(level);
  lcd.print("%");
  lcd.setCursor(0, 1);
  if (level <= 10) {
    lcd.print("Tank Empty");
  } else if (level <= 50) {
    lcd.print("Tank Half Full");
  } else {
    lcd.print("Tank Full");
  }
  updateIndicators(level);
}

void blindBeepLevel(int percentUsed) {
  if (percentUsed >= 7) {
    beepCount(3);
  } else if (percentUsed >= 4) {
    beepCount(2);
  } else {
    beepCount(1);
  }
}

void beepCount(int count) {
  for (int i = 0; i < count; i++) {
    tone(BLIND_BUZZER_PIN, 1500);
    delay(300);
    noTone(BLIND_BUZZER_PIN);
    delay(200);
  }
}

void loop() {
  long distance = readDistanceCM();
  bool glassPresent = (distance < 5);
  bool refillPressed = digitalRead(REFILL_BUTTON_PIN) == LOW;

  if (refillPressed) {
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("Filling Tank...");
    delay(300);
    int potLevel = analogRead(POT_PIN);
    int potPercent = map(potLevel, 0, 1023, 0, 100);
    waterLevelPercent = potPercent;
    showWaterLevel(waterLevelPercent);
    delay(500);
    return;
  }

  // Start dispensing
  if (!dispensing && glassPresent && !glassWasPresent && waterLevelPercent > 0) {
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("Dispensing Water");
    dispensing = true;
    dispenseStartTime = millis();
    waitingForGlassRemoval = true;
  }

  // During dispensing
  if (dispensing) {
    if (!glassPresent && waitingForGlassRemoval) {
      unsigned long dispenseDuration = millis() - dispenseStartTime;
      float mlDispensed = dispenseDuration / 1000.0; // 1 sec = 1 ml
      int percentUsed = mlDispensed * 0.5; // 1 ml = 0.5%
      if (percentUsed < 1) percentUsed = 1;
      waterLevelPercent -= percentUsed;
      if (waterLevelPercent < 0) waterLevelPercent = 0;
      showWaterLevel(waterLevelPercent);
      blindBeepLevel(percentUsed);
      dispensing = false;
      waitingForGlassRemoval = false;
    } else if (millis() - dispenseStartTime > 15000) {
      int percentUsed = 7;
      waterLevelPercent -= percentUsed;
      if (waterLevelPercent < 0) waterLevelPercent = 0;
      showWaterLevel(waterLevelPercent);
      blindBeepLevel(percentUsed);
      dispensing = false;
      waitingForGlassRemoval = false;
    }
  }

  glassWasPresent = glassPresent;
  delay(500);
}