// ESP32 Sicaklik Loglayici — TEST MODU (10 sn interval)
// DHT22 + DS1307 RTC + microSD + SSD1306 OLED
// OLED yerlesimi: her satir merkezlenmis, status alt bantta

#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <RTClib.h>
#include <DHT.h>
#include <SPI.h>
#include <SD.h>

#define DHT_PIN      4
#define DHT_TYPE     DHT22
#define SD_CS        5
#define LED_STATUS   15

#define OLED_W       128
#define OLED_H       64
#define OLED_ADDR    0x3C

#define LOG_INTERVAL_MS 10000UL   // TEST: 10 sn (prod: 60000)

DHT dht(DHT_PIN, DHT_TYPE);
RTC_DS1307 rtc;
Adafruit_SSD1306 oled(OLED_W, OLED_H, &Wire, -1);

uint32_t logCount = 0;
uint32_t lastLogMs = 0;
bool     sdOk = false;
bool     rtcOk = false;
float    lastTemp = 0.0;
float    lastHum = 0.0;
String   lastStamp = "Bekleniyor...";

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

// Metni belirtilen y'de x-ekseninde ortalar
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 twoDig(int n) { return (n < 10) ? "0" + String(n) : String(n); }
String euDate(DateTime d) { return twoDig(d.day()) + "." + twoDig(d.month()) + "." + String(d.year()); }
String hhmmss(DateTime d) { return twoDig(d.hour()) + ":" + twoDig(d.minute()) + ":" + twoDig(d.second()); }
String isoDate(DateTime d) { return String(d.year()) + "-" + twoDig(d.month()) + "-" + twoDig(d.day()); }

// ============ EKRANLAR ============
void drawSplash() {
  oled.clearDisplay();
  oled.setTextColor(SSD1306_WHITE);
  oled.drawRoundRect(2, 2, 124, 60, 6, SSD1306_WHITE);
  centered(14, 2, "BlueGrays");
  centered(36, 1, "Sicaklik Logger");
  centered(50, 1, "v1.0  DHT22 + RTC");
  oled.display();
}

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

  // Baslik
  centered(0, 1, "Sicaklik Logger");
  oled.drawLine(0, 10, 127, 10, SSD1306_WHITE);

  // Buyuk sicaklik degeri
  String tempStr = String(lastTemp, 1) + " C";
  centered(15, 2, tempStr);

  // Nem (sol) + kayit sayaci (sag)
  String humStr = "Nem: %" + String(lastHum, 1);
  lcdAt(0, 36, 1, humStr);
  String cnt = "#" + String(logCount);
  int cntW = cnt.length() * 6;
  lcdAt(128 - cntW, 36, 1, cnt);

  oled.drawLine(0, 45, 127, 45, SSD1306_WHITE);

  // Zaman damgasi (orta)
  centered(47, 1, lastStamp);

  // Alt bant: SD + RTC durum (orta)
  String stat = String(sdOk ? "SD:OK" : "SD:X ") + "   " + String(rtcOk ? "RTC:OK" : "RTC:X");
  centered(57, 1, stat);

  oled.display();
}

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

  pinMode(LED_STATUS, OUTPUT);
  digitalWrite(LED_STATUS, LOW);

  Wire.begin();

  if (!oled.begin(SSD1306_SWITCHCAPVCC, OLED_ADDR)) {
    Serial.println("[X] OLED bulunamadi");
    while (1) delay(100);
  }
  drawSplash();
  delay(2500);

  dht.begin();
  Serial.println("[OK] DHT22 baslatildi");

  if (!rtc.begin()) {
    Serial.println("[X] DS1307 bulunamadi");
    rtcOk = false;
  } else {
    rtcOk = true;
    if (!rtc.isrunning()) {
      Serial.println("[!] RTC calismiyordu, derleme zamanina ayarlandi");
      rtc.adjust(DateTime(F(__DATE__), F(__TIME__)));
    }
    Serial.println("[OK] RTC hazir: " + isoDate(rtc.now()) + " " + hhmmss(rtc.now()));
  }

  if (!SD.begin(SD_CS)) {
    Serial.println("[X] SD kart baslatilamadi (CS=GPIO 5)");
    sdOk = false;
  } else {
    sdOk = true;
    Serial.println("[OK] SD kart hazir");

    if (!SD.exists("/temp_log.csv")) {
      File f = SD.open("/temp_log.csv", FILE_WRITE);
      if (f) {
        f.println("tarih,saat,sicaklik_C,nem_yuzde,log_no");
        f.close();
        Serial.println("[OK] /temp_log.csv header yazildi");
      }
    }
  }

  drawStatus();
  Serial.println("== Kayit baslatildi (test modu 10 sn) ==");
}

// ============ LOG ============
void logNow() {
  float t = dht.readTemperature();
  float h = dht.readHumidity();

  if (isnan(t) || isnan(h)) {
    Serial.println("[!] DHT okuma HATASI");
    return;
  }

  lastTemp = t;
  lastHum = h;

  DateTime now = rtcOk ? rtc.now() : DateTime((uint32_t)(millis() / 1000));
  lastStamp = euDate(now) + " " + hhmmss(now);
  logCount++;

  Serial.printf("[%s] T=%.1fC H=%.1f%% #%lu\n",
                lastStamp.c_str(), t, h, (unsigned long)logCount);

  if (sdOk) {
    File f = SD.open("/temp_log.csv", FILE_APPEND);
    if (f) {
      f.printf("%s,%s,%.1f,%.1f,%lu\n",
               isoDate(now).c_str(), hhmmss(now).c_str(), t, h, (unsigned long)logCount);
      f.close();
    } else {
      Serial.println("[X] SD yazma HATASI");
    }
  }

  digitalWrite(LED_STATUS, HIGH);
  delay(80);
  digitalWrite(LED_STATUS, LOW);

  drawStatus();
}

// ============ LOOP ============
void loop() {
  uint32_t now = millis();
  if (now - lastLogMs >= LOG_INTERVAL_MS || lastLogMs == 0) {
    lastLogMs = now;
    logNow();
  }
  delay(200);
}