#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include <WiFi.h>
#include "time.h"
#include <OneWire.h>
#include <DallasTemperature.h>

// LCD setup (20x4 LCD, common I2C address 0x27 or 0x3F)
LiquidCrystal_I2C lcd(0x27, 20, 4);

// WiFi credentials
const char* ssid     = "Wokwi-GUEST";
const char* password = "";

// NTP Server & Timezone (India = GMT+5:30)
const char* ntpServer = "pool.ntp.org";
const long  gmtOffset_sec = 19800;  // GMT+5:30 in seconds
const int   daylightOffset_sec = 0;

// Days of the week
const char* daysOfTheWeek[7] = {"Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"};

// DS18B20 setup
#define ONE_WIRE_BUS 4   // GPIO4 (D4) on ESP32
OneWire oneWire(ONE_WIRE_BUS);
DallasTemperature sensors(&oneWire);

void setup() {
  Serial.begin(115200);

  // Initialize LCD
  lcd.init();
  lcd.backlight();

  // Connect Wi-Fi
  WiFi.begin(ssid, password);
  lcd.setCursor(0,0);
  lcd.print("Connecting WiFi...");
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  lcd.clear();
  lcd.setCursor(0,0);
  lcd.print("WiFi Connected!");

  // Init NTP
  configTime(gmtOffset_sec, daylightOffset_sec, ntpServer);

  // Init DS18B20
  sensors.begin();
}

void loop() {
  struct tm timeinfo;
  if(!getLocalTime(&timeinfo)){
    lcd.clear();
    lcd.setCursor(0,0);
    lcd.print("Time Error!");
    return;
  }

  // Read temperature
  sensors.requestTemperatures();
  float temperatureC = sensors.getTempCByIndex(0);

  lcd.clear();

  // Line 1: Date
  lcd.setCursor(0,0);
  lcd.printf("Date: %02d/%02d/%04d", timeinfo.tm_mday, timeinfo.tm_mon+1, timeinfo.tm_year+1900);

  // Line 2: Time
  lcd.setCursor(0,1);
  lcd.printf("Time: %02d:%02d:%02d", timeinfo.tm_hour, timeinfo.tm_min, timeinfo.tm_sec);

  // Line 3: Day
  lcd.setCursor(0,2);
  lcd.printf("Day : %s", daysOfTheWeek[timeinfo.tm_wday]);

  // Line 4: Temperature
  lcd.setCursor(0,3);
  if (temperatureC == DEVICE_DISCONNECTED_C) {
    lcd.print("Temp: Sensor Error");
  } else {
    lcd.printf("Temp: %.2f%cC", temperatureC, 223);
  }

  delay(1000);
}