#define trigPin1 2
#define echoPin1 3
#define trigPin2 4
#define echoPin2 5
#define buzzerPin 6
#define pirPin 7
#define buttonIgnorePIR 8
#define buttonManualBuzz 9

const unsigned long ON_TIME = 2500;
const unsigned long OFF_TIME = 2500;
const int BUZZ_FREQ = 1000;
const unsigned long IGNORE_PIR_DURATION = 120000; // 2 minutes
const unsigned long MANUAL_BUZZ_DURATION = 3000;  // 3 seconds
const unsigned long UPDATE_INTERVAL = 5000;       // 5 seconds

unsigned long lastToggle = 0;
bool buzzerOnState = false;

unsigned long ignorePIRStart = 0;
bool ignoringPIR = false;
bool pirTriggered = false;
bool ignoreButtonLockout = false;

unsigned long manualBuzzStart = 0;
bool manualBuzzing = false;

unsigned long lastUpdate = 0;

float getDistanceCM(int trigPin, int echoPin) {
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  long duration = pulseIn(echoPin, HIGH);
  return duration * 0.0343 / 2.0;
}

void setup() {
  Serial.begin(9600);
  pinMode(trigPin1, OUTPUT);
  pinMode(echoPin1, INPUT);
  pinMode(trigPin2, OUTPUT);
  pinMode(echoPin2, INPUT);
  pinMode(buzzerPin, OUTPUT);
  pinMode(pirPin, INPUT);
  pinMode(buttonIgnorePIR, INPUT_PULLUP);
  pinMode(buttonManualBuzz, INPUT_PULLUP);
  noTone(buzzerPin);
}

void loop() {
  unsigned long now = millis();

  // --- PIR and Button States ---
  bool pirState = digitalRead(pirPin) == HIGH;
  bool manualBtnPressed = digitalRead(buttonManualBuzz) == LOW;

  // --- Ignore PIR Button Edge Detection and Logic ---
  static bool prevIgnoreBtnState = HIGH;
  bool currentIgnoreBtnState = digitalRead(buttonIgnorePIR);
  bool ignoreBtnFallingEdge = (prevIgnoreBtnState == HIGH && currentIgnoreBtnState == LOW);
  prevIgnoreBtnState = currentIgnoreBtnState;

  if (ignoreBtnFallingEdge) {
    if (!ignoringPIR) {
      ignoringPIR = true;
      ignorePIRStart = now;
      ignoreButtonLockout = true;
      Serial.println("PIR ignoring started for 2 minutes...");
    } else {
      ignoringPIR = false;
      ignoreButtonLockout = false;
      Serial.println("PIR ignoring cancelled early.");
    }
  }

  if (ignoringPIR && now - ignorePIRStart >= IGNORE_PIR_DURATION) {
    ignoringPIR = false;
    ignoreButtonLockout = false;
    Serial.println("PIR ignoring ended (timeout).");
  }

  // --- Manual Buzz Button ---
  if (manualBtnPressed && !manualBuzzing) {
    manualBuzzing = true;
    manualBuzzStart = now;
    tone(buzzerPin, BUZZ_FREQ);
    Serial.println("Manual buzzer triggered.");
  }

  if (manualBuzzing && now - manualBuzzStart >= MANUAL_BUZZ_DURATION) {
    manualBuzzing = false;
    noTone(buzzerPin);
  }

  // Skip main logic if manually buzzing
  if (manualBuzzing) {
    delay(50);
    return;
  }

  // --- Sensor & Buzzer Logic every 5 seconds ---
  if (now - lastUpdate >= UPDATE_INTERVAL) {
    lastUpdate = now;

    // PIR logic
    if (!ignoringPIR && pirState) {
      pirTriggered = true;
    } else {
      pirTriggered = false;
    }

    // Read Sensors
    float d1 = getDistanceCM(trigPin1, echoPin1);
    float d2 = getDistanceCM(trigPin2, echoPin2);
    float avg = (d1 + d2) / 2.0;

    Serial.print("D1: "); Serial.print(d1);
    Serial.print(" cm | D2: "); Serial.print(d2);
    Serial.print(" cm | Avg: "); Serial.print(avg);
    Serial.print(" cm | PIR: "); Serial.println(pirTriggered ? "Motion" : "None");

    // Buzzer Pattern Decision
    if ((avg >= 2.0 && avg <= 50.0) && !pirTriggered) {
      buzzerOnState = true;
      tone(buzzerPin, BUZZ_FREQ);
      lastToggle = now;
    } else {
      buzzerOnState = false;
      noTone(buzzerPin);
    }
  }

  // Turn buzzer off after 2.5s if it was turned on during last update
  if (buzzerOnState && now - lastToggle >= ON_TIME) {
    buzzerOnState = false;
    noTone(buzzerPin);
  }

  delay(50);
}