#include <EEPROM.h>
#include <TimerOne.h>
#include <LiquidCrystal_I2C.h>

// LCD I2C
LiquidCrystal_I2C lcd(0x27, 16, 2);

// --- تنظیمات ---
#define NUM_SENSORS 3
#define NUM_REMOTE_KEYS 4

// --- پین‌ها ---
const int sensorPins[NUM_SENSORS] = {2, 3, 4};
const int remotePins[NUM_REMOTE_KEYS] = {6, 7, 8, 9};
const int buzzerPin = 5;
const int ledArmedPin = 10;
const int ledDisarmedPin = 11;
const int ledSilentPin = 12;
const int ledSensorPins[NUM_SENSORS] = {A0, A1, A2};

// --- باتری ---
const int batteryRelayPin = A5;
const int batteryAnalogPin = A3;
const float batteryStartCharge = 12.4;
const float batteryStopCharge = 12.6;
const float batteryDividerRatio = 2.6;

// EEPROM
#define EEPROM_ADDR_ARMED 0
#define EEPROM_ADDR_SILENT 1

// وضعیت سیستم
bool systemArmed = false;
bool silentMode = false;
bool buzzerActive = false;
bool sensorTriggered = false;
bool sensorLatched[NUM_SENSORS] = {false};
bool remoteLock[NUM_REMOTE_KEYS] = {false};
bool isCharging = false;
unsigned long lastMotionTime = 0;
const unsigned long alarmDuration = 20000;

// کنترل LCD
unsigned long lcdActiveUntil = 0;
bool lcdIsOn = true;
bool alarmStoppedByRemote = false;
bool alarmStoppedAuto = false;
int lastTriggeredSensor = -1;

// بوق
volatile bool beepRequested = false;
volatile int beepCount = 0;

// باتری
volatile bool batteryCheckFlag = false;
volatile unsigned int batteryCheckCounter = 0;

// --- توابع LCD ---
void lcdBacklightControl() {
  if (millis() > lcdActiveUntil && lcdIsOn) {
    lcd.noBacklight();
    lcdIsOn = false;
  }
}

void showOnLCD(String line1, String line2) {
  lcd.clear();
  lcd.setCursor(0, 0); lcd.print(line1);
  lcd.setCursor(0, 1); lcd.print(line2);
  lcd.backlight();
  lcdIsOn = true;
  lcdActiveUntil = millis() + 20000;
}

// --- EEPROM ---
void saveSystemState() {
  EEPROM.write(EEPROM_ADDR_ARMED, systemArmed);
  EEPROM.write(EEPROM_ADDR_SILENT, silentMode);
}

void loadSystemState() {
  systemArmed = EEPROM.read(EEPROM_ADDR_ARMED);
  silentMode = EEPROM.read(EEPROM_ADDR_SILENT);
  Serial.println(systemArmed ? (silentMode ? "✅ Silent ARMED" : "✅ ARMED") : "❌ DISARMED");
}

// --- تایمر ---
void requestBeep(int times) {
  if (!beepRequested) {
    beepCount = times * 2;
    beepRequested = true;
  }
}

void timerISR() {
  static bool buzzerState = false;
  static int intervalCounter = 0;

  if (beepRequested && beepCount > 0) {
    if (intervalCounter == 0) {
      buzzerState = !buzzerState;
      digitalWrite(buzzerPin, buzzerState);
      if (!buzzerState && --beepCount == 0)
        beepRequested = false;
      intervalCounter = 2;
    } else intervalCounter--;
  }

  batteryCheckCounter++;
  if (batteryCheckCounter >= 40) {
    batteryCheckCounter = 0;
    batteryCheckFlag = true;
  }
}

// --- آژیر ---
void activateAlarm() {
  if (!silentMode) {
    buzzerActive = true;
    digitalWrite(buzzerPin, HIGH);
  }
}

// --- وضعیت LED ---
void updateStatusLEDs() {
  digitalWrite(ledArmedPin, systemArmed && !silentMode);
  digitalWrite(ledSilentPin, systemArmed && silentMode);
  digitalWrite(ledDisarmedPin, !systemArmed);
  for (int i = 0; i < NUM_SENSORS; i++)
    digitalWrite(ledSensorPins[i], sensorLatched[i]);
}

void resetSensorLEDs() {
  for (int i = 0; i < NUM_SENSORS; i++) {
    sensorLatched[i] = false;
    digitalWrite(ledSensorPins[i], LOW);
  }
}

// --- باتری ---
void checkBattery() {
  int rawBattery = analogRead(batteryAnalogPin);
  float voltageBattery = (rawBattery * 5.0 / 1023.0) * batteryDividerRatio;

  if (!isCharging && voltageBattery < batteryStartCharge) {
    digitalWrite(batteryRelayPin, HIGH);
    isCharging = true;
    Serial.println("🔋 Charging started");
  }
  else if (isCharging && voltageBattery >= batteryStopCharge) {
    digitalWrite(batteryRelayPin, LOW);
    isCharging = false;
    Serial.println("✅ Charging stopped");
  }
}

void showBatteryPercentage() {
  int rawBattery = analogRead(batteryAnalogPin);
  float voltageBattery = (rawBattery * 5.0 / 1023.0) * batteryDividerRatio;
  float percentage = ((voltageBattery - 11.0) / (12.6 - 11.0)) * 100.0;
  if (percentage > 100) percentage = 100;
  if (percentage < 0) percentage = 0;

  Serial.print("🔋 Battery: ");
  Serial.print(percentage, 1);
  Serial.println(" %");

  String status = (systemArmed ? (silentMode ? "ARMED-SILENT" : "ARMED") : "DISARMED");
  String line1 = "Stat:" + status;
  String line2 = "Bat:" + String((int)percentage) + "% " + (isCharging ? "Chg" : "OK");
  showOnLCD(line1, line2);
}

// --- ریموت ---
void handleRemoteCommand(int key) {
  lcdActiveUntil = millis() + 20000;
  switch (key) {
    case 0:
      systemArmed = true; silentMode = false; sensorTriggered = false;
      resetSensorLEDs(); saveSystemState(); requestBeep(1);
      Serial.println("✅ Armed (normal)");
      showOnLCD("System ARMED", "Normal Mode");
      break;

    case 1:
      systemArmed = false; silentMode = false;
      buzzerActive = false; sensorTriggered = false;
      digitalWrite(buzzerPin, LOW);
      saveSystemState(); requestBeep(1);
      Serial.println("❌ Disarmed");
      showOnLCD("Alarm stopped", "(remote)");
      alarmStoppedByRemote = true;
      break;

    case 2:
      systemArmed = true; silentMode = true; sensorTriggered = false;
      resetSensorLEDs(); saveSystemState(); requestBeep(1);
      Serial.println("🔇 Armed (silent)");
      showOnLCD("System ARMED", "Silent Mode");
      break;

    case 3:
      if (buzzerActive) {
        buzzerActive = false;
        digitalWrite(buzzerPin, LOW);
        requestBeep(1);
        Serial.println("🛑 Alarm stopped");
        showOnLCD("Alarm stopped", "(remote)");
        alarmStoppedByRemote = true;
      }
      break;
  }
  updateStatusLEDs();
}

// --- setup ---
void setup() {
  Serial.begin(9600);
  Serial.println("🛡️ System started");

  lcd.init();
  lcd.backlight();
  showOnLCD("System Loading...", "");
  delay(1000);

  for (int i = 0; i < NUM_SENSORS; i++) {
    pinMode(sensorPins[i], INPUT);
    pinMode(ledSensorPins[i], OUTPUT);
  }
  for (int i = 0; i < NUM_REMOTE_KEYS; i++) pinMode(remotePins[i], INPUT);

  pinMode(buzzerPin, OUTPUT);
  pinMode(ledArmedPin, OUTPUT);
  pinMode(ledDisarmedPin, OUTPUT);
  pinMode(ledSilentPin, OUTPUT);
  pinMode(batteryRelayPin, OUTPUT);
  digitalWrite(batteryRelayPin, LOW);

  Timer1.initialize(100000);
  Timer1.attachInterrupt(timerISR);

  loadSystemState();
  updateStatusLEDs();
  showBatteryPercentage();
}

// --- loop ---
void loop() {
  for (int i = 0; i < NUM_REMOTE_KEYS; i++) {
    if (digitalRead(remotePins[i]) == HIGH && !remoteLock[i]) {
      handleRemoteCommand(i);
      remoteLock[i] = true;
    } else if (digitalRead(remotePins[i]) == LOW) {
      remoteLock[i] = false;
    }
  }

  if (systemArmed) {
    for (int i = 0; i < NUM_SENSORS; i++) {
      if (digitalRead(sensorPins[i]) == HIGH) {
        sensorTriggered = true;
        lastMotionTime = millis();
        activateAlarm();
        if (!sensorLatched[i]) {
          sensorLatched[i] = true;
          lastTriggeredSensor = i;
          Serial.print("🚨 Triggered sensor ");
          Serial.println(i + 1);
          updateStatusLEDs();
          showOnLCD("ALARM TRIGGERED", "Sensor #" + String(i + 1));
        }
      }
    }
  }

  if (buzzerActive && millis() - lastMotionTime > alarmDuration) {
    buzzerActive = false;
    digitalWrite(buzzerPin, LOW);
    Serial.println("🔕 Auto alarm off");
    showOnLCD("Alarm auto", "stopped");
    alarmStoppedAuto = true;
  }

  if ((alarmStoppedByRemote || alarmStoppedAuto) && millis() - lastMotionTime > 3000) {
    alarmStoppedByRemote = false;
    alarmStoppedAuto = false;
    showBatteryPercentage();
  }

  checkBattery();
  if (batteryCheckFlag) {
    batteryCheckFlag = false;
    showBatteryPercentage();
  }

  lcdBacklightControl();
}