// ESP32 Hareket Alarm Sistemi (Motion Alarm System)
// TR: PIR sensor + siren buzzer + 2 LED (alarm/ready) + OLED durum + opsiyonel Telegram bildirimi
// EN: PIR sensor + siren buzzer + 2 LEDs (alarm/ready) + OLED status + optional Telegram notification
// TR: Hareket alginca kirmizi LED + siren + OLED "ALARM!" + Telegram (etkinse). Sakin durumda yesil LED "GUVENLI".
// EN: On motion: red LED + siren + OLED "ALARM!" + Telegram (if enabled). When calm: green LED "SAFE".

#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

// ============ TELEGRAM (OPSIYONEL / OPTIONAL) ============
// TR: Wokwi'de test icin ENABLE_TELEGRAM false birak. Gercek donanimda true yap ve credentials doldur.
// EN: Keep ENABLE_TELEGRAM false for Wokwi testing. Set true on real hardware with credentials.
#define ENABLE_TELEGRAM false

#if ENABLE_TELEGRAM
  #include <WiFi.h>
  #include <WiFiClientSecure.h>
  #include <HTTPClient.h>
  const char* WIFI_SSID = "YourWiFi";
  const char* WIFI_PASS = "YourPassword";
  const String TG_BOT_TOKEN = "123456789:AAABBBCCCdddEEE";  // TR: BotFather'dan / EN: from BotFather
  const String TG_CHAT_ID = "-1001234567890";                // TR: Chat/kanal ID | EN: Chat/channel ID
#endif

// ============ PIN TANIMLARI / PIN DEFINITIONS ============
#define PIR_PIN      18     // TR: PIR sensor OUT | EN: PIR sensor OUT
#define LED_RED      15     // TR: Alarm LED (kirmizi) | EN: Alarm LED (red)
#define LED_GREEN    4      // TR: Ready LED (yesil) | EN: Ready LED (green)
#define BUZZER_PIN   5      // TR: Aktif buzzer | EN: Active buzzer

// ============ OLED AYARLARI / OLED CONFIG ============
#define OLED_W       128
#define OLED_H       64
#define OLED_ADDR    0x3C

// ============ DAVRANIS / BEHAVIOR ============
#define CALIB_MS         3000UL   // TR: Baslangic kalibrasyon (Wokwi 3sn, gercek 30-60sn) | EN: Startup calibration
#define ALARM_HOLD_MS    5000UL   // TR: Hareket sonrasi alarm suresi | EN: Alarm duration after motion
#define SIREN_TOGGLE_MS  120      // TR: Siren frekansi (ms) | EN: Siren toggle interval (ms)
#define TG_COOLDOWN_MS   30000UL  // TR: Telegram spam engelleme (30sn) | EN: Telegram anti-spam (30 sec)

// ============ NESNELER / OBJECTS ============
Adafruit_SSD1306 oled(OLED_W, OLED_H, &Wire, -1);

// ============ DURUM DEGISKENLERI / STATE VARIABLES ============
bool     alarmActive = false;
uint32_t alarmStartMs = 0;
uint32_t lastSirenToggle = 0;
bool     sirenState = false;
uint32_t alarmCount = 0;
uint32_t lastTgSentMs = 0;
uint32_t bootMs = 0;
bool     calibrating = true;
String   lastAlarmStamp = "-";

// ============ YARDIMCILAR / HELPERS ============
void lcdAt(int x, int y, uint8_t size, const String &t) {
  oled.setTextSize(size);
  oled.setCursor(x, y);
  oled.print(t);
}

void centered(uint8_t y, uint8_t size, const String &t) {
  int w = t.length() * 6 * size;
  int x = (128 - w) / 2;
  if (x < 0) x = 0;
  lcdAt(x, y, size, t);
}

String fmtDuration(uint32_t ms) {
  uint32_t sec = ms / 1000;
  uint32_t h = sec / 3600;
  uint32_t m = (sec % 3600) / 60;
  uint32_t s = sec % 60;
  String out = "";
  if (h > 0) out += String(h) + "s ";
  if (m > 0) out += String(m) + "d ";
  out += String(s) + "sn";
  return out;
}

// ============ EKRANLAR / SCREENS ============
void drawSplash() {
  oled.clearDisplay();
  oled.setTextColor(SSD1306_WHITE);
  oled.drawRoundRect(2, 2, 124, 60, 6, SSD1306_WHITE);
  centered(14, 2, "BlueGrays");
  centered(36, 1, "Hareket Alarm");
  centered(50, 1, "v1.0  PIR + Siren");
  oled.display();
}

void drawCalibrating(uint32_t remaining) {
  oled.clearDisplay();
  oled.setTextColor(SSD1306_WHITE);
  centered(4, 1, "PIR Kalibrasyon");
  oled.drawLine(0, 14, 127, 14, SSD1306_WHITE);
  centered(24, 2, String(remaining) + "s");
  centered(48, 1, "Lutfen bekleyin...");
  oled.display();
}

void drawReady() {
  oled.clearDisplay();
  oled.setTextColor(SSD1306_WHITE);

  // TR: Baslik | EN: Title
  centered(0, 1, "Hareket Alarm");
  oled.drawLine(0, 10, 127, 10, SSD1306_WHITE);

  // TR: Buyuk durum | EN: Big status
  centered(16, 2, "GUVENLI");

  oled.drawLine(0, 42, 127, 42, SSD1306_WHITE);
  lcdAt(0, 45, 1, "Son: " + lastAlarmStamp);
  lcdAt(0, 55, 1, "Alarm: " + String(alarmCount));

  // Ready indicator (sag alt)
  oled.fillCircle(120, 60, 3, SSD1306_WHITE);

  oled.display();
}

void drawAlarm() {
  oled.clearDisplay();
  oled.setTextColor(SSD1306_WHITE);

  // TR: Cerceve (invert efekt) | EN: Frame (invert-like effect)
  oled.drawRect(0, 0, 128, 64, SSD1306_WHITE);
  oled.drawRect(2, 2, 124, 60, SSD1306_WHITE);

  centered(12, 3, "ALARM!");
  centered(40, 1, "HAREKET ALGILANDI");
  centered(52, 1, "#" + String(alarmCount));

  oled.display();
}

// ============ TELEGRAM ============
#if ENABLE_TELEGRAM
void sendTelegram(const String &msg) {
  if (WiFi.status() != WL_CONNECTED) {
    Serial.println("[TG] WiFi yok / no WiFi");
    return;
  }
  WiFiClientSecure client;
  client.setInsecure();  // TR: Sertifika dogrulamayi atla | EN: Skip cert verify (basit test icin)

  HTTPClient https;
  String url = "https://api.telegram.org/bot" + TG_BOT_TOKEN + "/sendMessage";
  if (https.begin(client, url)) {
    https.addHeader("Content-Type", "application/x-www-form-urlencoded");
    String payload = "chat_id=" + TG_CHAT_ID + "&text=" + msg;
    int code = https.POST(payload);
    Serial.printf("[TG] HTTP %d\n", code);
    https.end();
  }
}
#endif

// ============ SIREN ============
void siren() {
  uint32_t now = millis();
  if (now - lastSirenToggle >= SIREN_TOGGLE_MS) {
    lastSirenToggle = now;
    sirenState = !sirenState;
    digitalWrite(BUZZER_PIN, sirenState ? HIGH : LOW);
    digitalWrite(LED_RED, sirenState ? HIGH : LOW);
  }
}

// ============ SETUP ============
void setup() {
  Serial.begin(115200);
  delay(500);

  pinMode(PIR_PIN, INPUT);
  pinMode(LED_RED, OUTPUT);
  pinMode(LED_GREEN, OUTPUT);
  pinMode(BUZZER_PIN, OUTPUT);
  digitalWrite(LED_RED, LOW);
  digitalWrite(LED_GREEN, LOW);
  digitalWrite(BUZZER_PIN, LOW);

  Wire.begin();
  if (!oled.begin(SSD1306_SWITCHCAPVCC, OLED_ADDR)) {
    Serial.println("[X] OLED bulunamadi / not found");
    while (1) delay(100);
  }
  drawSplash();
  delay(2000);

#if ENABLE_TELEGRAM
  Serial.println("[WiFi] baglaniyor / connecting...");
  WiFi.begin(WIFI_SSID, WIFI_PASS);
  uint32_t t0 = millis();
  while (WiFi.status() != WL_CONNECTED && millis() - t0 < 15000) {
    delay(300);
    Serial.print(".");
  }
  Serial.println();
  if (WiFi.status() == WL_CONNECTED) {
    Serial.println("[WiFi] baglandi / connected: " + WiFi.localIP().toString());
  } else {
    Serial.println("[WiFi] baglanti basarisiz / failed");
  }
#endif

  bootMs = millis();
  Serial.println("== Sistem baslatildi, kalibrasyon / System started, calibrating ==");
}

// ============ LOOP ============
void loop() {
  uint32_t now = millis();

  // TR: Kalibrasyon fazi | EN: Calibration phase
  if (calibrating) {
    uint32_t elapsed = now - bootMs;
    if (elapsed >= CALIB_MS) {
      calibrating = false;
      digitalWrite(LED_GREEN, HIGH);
      drawReady();
      Serial.println("[OK] Kalibrasyon tamam, sistem hazir / Calibration done, system ready");
    } else {
      uint32_t remaining = (CALIB_MS - elapsed) / 1000 + 1;
      drawCalibrating(remaining);
      // TR: Kalibrasyon sirasinda LED'ler alternate blink | EN: LEDs alternate blink during calib
      digitalWrite(LED_GREEN, (now / 200) % 2);
      delay(100);
      return;
    }
  }

  // TR: PIR durumunu oku | EN: Read PIR state
  int motion = digitalRead(PIR_PIN);

  if (motion == HIGH && !alarmActive) {
    // TR: YENI alarm | EN: NEW alarm
    alarmActive = true;
    alarmStartMs = now;
    alarmCount++;
    lastAlarmStamp = fmtDuration(now - bootMs) + " once";
    digitalWrite(LED_GREEN, LOW);
    drawAlarm();

    Serial.printf("[!] HAREKET / MOTION #%lu at t=%lu ms\n", (unsigned long)alarmCount, (unsigned long)now);

#if ENABLE_TELEGRAM
    if (now - lastTgSentMs > TG_COOLDOWN_MS) {
      lastTgSentMs = now;
      String msg = "ALARM! Hareket algilandi (motion detected) #" + String(alarmCount);
      sendTelegram(msg);
    }
#endif
  }

  if (alarmActive) {
    siren();
    if (now - alarmStartMs > ALARM_HOLD_MS && motion == LOW) {
      // TR: Alarm bitir | EN: End alarm
      alarmActive = false;
      digitalWrite(BUZZER_PIN, LOW);
      digitalWrite(LED_RED, LOW);
      digitalWrite(LED_GREEN, HIGH);
      lastAlarmStamp = fmtDuration(now - bootMs) + " once";
      drawReady();
      Serial.println("[OK] Alarm bitti, sisteme donuldu / Alarm ended, back to ready");
    }
  }

  delay(50);
}