#ifndef TIME_MANAGER_H
#define TIME_MANAGER_H

#include <Arduino.h>
#include <time.h>
#include "udp_logger.h"

#define NTP_MAX_UPDATE_TIME_US (500 * 1000) // 500ms max update time

class TimeManager
{
public:
    struct tm time_info(void);
    bool ntp_sync_successful(void) const; // was there a NTP sync once?
    bool ntp_time_update(bool init = false);
    bool ntp_update_failed_prolonged(void) const; // indicates if maximum time since last NTP update was too long
    void log_time(struct tm time_info) const;     // log local_time
    void increment_time_now_local(void);

    int tm_min(void);
    int tm_hour(void);
    int tm_year(void);
    bool tm_isdst(void); // true if summertime

    TimeManager(const char *tz,
                const char *ntp_server,
                uint32 ntp_update_period_s,
                uint32 ntp_retry_delay_us,
                uint32 ntp_max_offline_time_s,
                UDPLogger *logger);

private:
    void set_up_ntp(void) const;       // set up NTP server
    void set_up_timer_isr(void) const; // set up timer interrupt
    const char *_tz;                   // timezone
    const char *_ntp_server;           // used ntp server
    UDPLogger *_logger;                // logger instance
    struct tm _time_info;              // structure tm holds time information
    time_t _time_now_local = 0;        // local timer value, updated by timer interrupt and synced by NTP when needed
    time_t _time_now_ntp = 0;          // NTP timer value, seconds since Epoch (1970) - UTC, only synced by NTP request.
    uint32 _ntp_max_offline_time_s;    // maximum time in seconds which is considered ok since last NTP update
    uint32 _ntp_update_period_s;       // NTP request update period in seconds
    uint32 _ntp_retry_delay_us;        // minimum retry delay in us between two NTP requests
    uint32 _ntp_sync_timestamp_us = 0; // timestamp of last successful ntp update
};

inline void TimeManager::increment_time_now_local(void)
{
    _time_now_local++;
}

#endif /* TIME_MANAGER_H */