NtpClient.h

#ifndef APP_NTPCLIENT_H_
#define APP_NTPCLIENT_H_

#include "UdpConnection.h"
#include "../Platform/System.h"
#include "../Timer.h"
#include "../SystemClock.h"
#include "../Platform/Station.h"
#include "../Delegate.h"

#define NTP_PORT 123
#define NTP_PACKET_SIZE 48
#define NTP_VERSION 4
#define NTP_MODE_CLIENT 3
#define NTP_MODE_SERVER 4

#define NTP_DEFAULT_SERVER "pool.ntp.org"
#define NTP_DEFAULT_QUERY_INTERVAL_SECONDS 600 // 10 minutes
#define NTP_RESPONSE_TIMEOUT_MS 20000 // 20 seconds

class NtpClient;

// Delegate constructor usage: (&YourClass::method, this)
typedef Delegate<void(NtpClient& client, time_t ntpTime)> NtpTimeResultDelegate;


class NtpClient : protected UdpConnection
{
public:
    NtpClient();

    NtpClient(NtpTimeResultDelegate onTimeReceivedCb);

    NtpClient(String reqServer, int reqIntervalSeconds, NtpTimeResultDelegate onTimeReceivedCb = nullptr);

    virtual ~NtpClient();

    void requestTime();

    void setNtpServer(String server);

    void setAutoQuery(bool autoQuery);

    void setAutoQueryInterval(int seconds);

    void setAutoUpdateSystemClock(bool autoUpdateClock);

protected:
    void onReceive(pbuf *buf, IPAddress remoteIP, uint16_t remotePort);

    void internalRequestTime(IPAddress serverIp);

protected:
    String server = NTP_DEFAULT_SERVER; 

    NtpTimeResultDelegate delegateCompleted = nullptr; 
    bool autoUpdateSystemClock = false; 

    Timer autoUpdateTimer; 
    Timer timeoutTimer; 
    Timer connectionTimer; 

    static void staticDnsResponse(const char *name, struct ip_addr *ip, void *arg);
};

#endif /* APP_NTPCLIENT_H_ */