// Pin Definitions
#define IGNITION_PIN 2       // D2: Ignition power input
#define DOOR_SWITCH_PIN 3    // D3: Door switch input (pull-up)
#define INDICATOR1_PIN 4     // D4: Indicator lamp 1
#define INDICATOR2_PIN 5     // D5: Indicator lamp 2
#define BRAKE_LAMP_PIN 6     // D6: Indicator brake lamp
#define LOCK_SIGNAL_INPUT 7  // D7: Lock signal input
#define UNLOCK_SIGNAL_INPUT 8 // D8: Unlock signal input
#define BUZZER_PIN 9         // D9: Buzzer output
#define LOCK_MODE_LED 10     // D10: Lock mode LED
#define LOCK_SIGNAL_OUTPUT 11 // D11: Lock signal output
#define UNLOCK_SIGNAL_OUTPUT 12 // D12: Unlock signal output

bool lockMode = false; // Track lock/unlock mode
unsigned long lastBlinkTime = 0;

void setup() {
  pinMode(IGNITION_PIN, INPUT);
  pinMode(DOOR_SWITCH_PIN, INPUT_PULLUP);
  pinMode(INDICATOR1_PIN, OUTPUT);
  pinMode(INDICATOR2_PIN, OUTPUT);
  pinMode(BRAKE_LAMP_PIN, OUTPUT);
  pinMode(LOCK_SIGNAL_INPUT, INPUT);
  pinMode(UNLOCK_SIGNAL_INPUT, INPUT);
  pinMode(BUZZER_PIN, OUTPUT);
  pinMode(LOCK_MODE_LED, OUTPUT);
  pinMode(LOCK_SIGNAL_OUTPUT, OUTPUT);
  pinMode(UNLOCK_SIGNAL_OUTPUT, OUTPUT);
}

void loop() {
  if (digitalRead(LOCK_SIGNAL_INPUT) == HIGH) {
    lockMode = true;
    lockSequence();
  }

  if (digitalRead(UNLOCK_SIGNAL_INPUT) == HIGH) {
    lockMode = false;
    unlockSequence();
  }

  if (lockMode && (digitalRead(DOOR_SWITCH_PIN) == LOW || digitalRead(IGNITION_PIN) == HIGH)) {
    alarmSequence();
  }
}

void lockSequence() {
  // Buzzer and LED synchronized beeping/blinking from 1kHz to 20kHz
  for (int freq = 1000; freq <= 20000; freq += 1000) {
    tone(BUZZER_PIN, freq, 200);
    digitalWrite(LOCK_MODE_LED, HIGH);
    delay(200);
    digitalWrite(LOCK_MODE_LED, LOW);
  }

  // Trigger lock signal
  digitalWrite(LOCK_SIGNAL_OUTPUT, HIGH);
  delay(1000);
  digitalWrite(LOCK_SIGNAL_OUTPUT, LOW);

  // Fade indicators in and out
  for (int i = 0; i < 2; i++) {
    fadeIndicators();
  }

  delay(5000); // Delay D2 and D3 detection
}

void unlockSequence() {
  // Buzzer and LED synchronized beeping/blinking from 20kHz to 1kHz
  for (int freq = 20000; freq >= 1000; freq -= 1000) {
    tone(BUZZER_PIN, freq, 200);
    digitalWrite(LOCK_MODE_LED, HIGH);
    delay(200);
    digitalWrite(LOCK_MODE_LED, LOW);
  }

  // Trigger unlock signal
  digitalWrite(UNLOCK_SIGNAL_OUTPUT, HIGH);
  delay(1000);
  digitalWrite(UNLOCK_SIGNAL_OUTPUT, LOW);

  // Blink indicators
  unsigned long startTime = millis();
  while (millis() - startTime < 5000) {
    blinkIndicators();
  }
}

void alarmSequence() {
  // Continuous buzzer and LED synchronized blinking
  tone(BUZZER_PIN, 20000);
  digitalWrite(LOCK_MODE_LED, HIGH);

  // Flash indicators
  blinkIndicators();

  // Fade brake lamp in and out
  fadeIndicators();
}

void blinkIndicators() {
  digitalWrite(INDICATOR1_PIN, HIGH);
  digitalWrite(INDICATOR2_PIN, HIGH);
  delay(500);
  digitalWrite(INDICATOR1_PIN, LOW);
  digitalWrite(INDICATOR2_PIN, LOW);
  delay(500);
}

void fadeIndicators() {
  for (int brightness = 0; brightness <= 255; brightness++) {
    analogWrite(INDICATOR1_PIN, brightness);
    analogWrite(INDICATOR2_PIN, brightness);
    analogWrite(BRAKE_LAMP_PIN, brightness);
    delay(10);
  }

  for (int brightness = 255; brightness >= 0; brightness--) {
    analogWrite(INDICATOR1_PIN, brightness);
    analogWrite(INDICATOR2_PIN, brightness);
    analogWrite(BRAKE_LAMP_PIN, brightness);
    delay(10);
  }
}