esp8266-react-framework/lib/framework/NTPSettingsService.h

#ifndef NTPSettingsService_h
#define NTPSettingsService_h

#include <AdminSettingsService.h>

#include <time.h>
#ifdef ESP32
#include <lwip/apps/sntp.h>
#elif defined(ESP8266)
#include <sntp.h>
#endif

// default time zone
#define NTP_SETTINGS_SERVICE_DEFAULT_ENABLED true
#define NTP_SETTINGS_SERVICE_DEFAULT_TIME_ZONE_LABEL "Europe/London"
#define NTP_SETTINGS_SERVICE_DEFAULT_TIME_ZONE_FORMAT "GMT0BST,M3.5.0/1,M10.5.0"
#define NTP_SETTINGS_SERVICE_DEFAULT_SERVER "time.google.com"

// min poll delay of 60 secs, max 1 day
#define NTP_SETTINGS_MIN_INTERVAL 60
#define NTP_SETTINGS_MAX_INTERVAL 86400

#define NTP_SETTINGS_FILE "/config/ntpSettings.json"
#define NTP_SETTINGS_SERVICE_PATH "/rest/ntpSettings"

class NTPSettings {
 public:
  bool enabled;
  String tzLabel;
  String tzFormat;
  String server;
};

class NTPSettingsService : public AdminSettingsService<NTPSettings> {
 public:
  NTPSettingsService(AsyncWebServer* server, FS* fs, SecurityManager* securityManager);
  ~NTPSettingsService();

  void loop();

 protected:
  void readFromJsonObject(JsonObject& root);
  void writeToJsonObject(JsonObject& root);
  void onConfigUpdated();
  void receivedNTPtime();

 private:
  bool _reconfigureNTP = false;

#ifdef ESP32
  void onStationModeGotIP(WiFiEvent_t event, WiFiEventInfo_t info);
  void onStationModeDisconnected(WiFiEvent_t event, WiFiEventInfo_t info);
#elif defined(ESP8266)
  WiFiEventHandler _onStationModeDisconnectedHandler;
  WiFiEventHandler _onStationModeGotIPHandler;

  void onStationModeGotIP(const WiFiEventStationModeGotIP& event);
  void onStationModeDisconnected(const WiFiEventStationModeDisconnected& event);
#endif

  void configureNTP();
};

#endif  // end NTPSettingsService_h