#define BLYNK_TEMPLATE_ID "TMPL6wJBZ1UwE"
#define BLYNK_TEMPLATE_NAME "Smart Alert"
#define BLYNK_AUTH_TOKEN "7YRSjbv5NTXycPyzuislimA46KzxIYen"
#define BLYNK_PRINT Serial

#include <WiFi.h>
#include <BlynkSimpleEsp32.h>

// Pins
#define LED 18
#define EMERGENCY_BTN 19  // Physical push button pin (must be interrupt-capable)

char ssid[] = "Wokwi-GUEST";
char pass[] = "";

volatile bool emergencyFlag = false;  // Marked volatile for interrupt
bool emergencyMode = false;
unsigned long lastBlinkTime = 0;
unsigned long lastDebounceTime = 0;
const unsigned long debounceDelay = 200;  // Debounce time in ms

const int buzzerPin = 5;  // GPIO pin connected to the passive buzzer
const int minFrequency = 500;  // Minimum frequency in Hz
const int maxFrequency = 2000; // Maximum frequency in Hz
const int stepDuration = 15;   // Time between frequency steps in ms
const int pauseBetweenCycles = 500; // Pause at the end of each siren cycle

WidgetLED led2(V0);

// Interrupt Service Routine (keep it short!)
IRAM_ATTR void handleInterrupt() {
  if ((millis() - lastDebounceTime) > debounceDelay) {
    emergencyFlag = true;
    lastDebounceTime = millis();
  }
}

void setup() {
  Serial.begin(115200);
  pinMode(LED, OUTPUT);
  pinMode(buzzerPin, OUTPUT);
  pinMode(EMERGENCY_BTN, INPUT_PULLUP);
  
  // Attach interrupt to the button pin
  attachInterrupt(digitalPinToInterrupt(EMERGENCY_BTN), handleInterrupt, FALLING);
  
  Blynk.begin(BLYNK_AUTH_TOKEN, ssid, pass);
}

void loop() {
  Blynk.run();
  
  // Check if interrupt was triggered
  if (emergencyFlag) {
    emergencyFlag = false;
    emergencyMode = true;
    Blynk.virtualWrite(V1, 1);  // Update Blynk switch
    Blynk.virtualWrite(V2, "Emergency State");
    Blynk.logEvent("mergency_alert","Emergency");
  }

  // Handle emergency/normal modes
  if (emergencyMode) {
    

    siren();
  } 
  else {
    // Normal mode - blink every 10 minutes
    if (millis() - lastBlinkTime >= 600000) {
      digitalWrite(LED, HIGH);
      led2.on();
      delay(200);
      digitalWrite(LED, LOW);
      led2.off();
      lastBlinkTime = millis();
    }
    Blynk.virtualWrite(V2, "Normal State");
  }
}

// Blynk switch can ONLY turn off emergency
BLYNK_WRITE(V1) {
  if (param.asInt() == 0) {
    emergencyMode = false;
   // digitalWrite(LED, LOW);
    noTone(buzzerPin);
    //led2.off();
    Blynk.virtualWrite(V2, "Neutralized State");
    delay(5000);

    digitalWrite(LED, LOW);
    led2.off();
    lastBlinkTime = millis();
  }
}

void siren() {
  // Rising tone (low to high frequency)
  for (int freq = minFrequency; freq <= maxFrequency; freq += 10) {
    tone(buzzerPin, freq);
    delay(stepDuration);
    digitalWrite(LED, HIGH);
    led2.on();
    delay(50);
    digitalWrite(LED, LOW);
    delay(50);
    led2.off();
  }
  
  // Falling tone (high to low frequency)
  for (int freq = maxFrequency; freq >= minFrequency; freq -= 10) {
    tone(buzzerPin, freq);
    delay(stepDuration);
    digitalWrite(LED, HIGH);
    led2.on();
    delay(50);
    digitalWrite(LED, LOW);
    delay(50);
    led2.off();
  }
  
  // Short pause between siren cycles
  noTone(buzzerPin);
  delay(pauseBetweenCycles);
}