#ifndef TIME_MANAGER_H
#define TIME_MANAGER_H

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

typedef enum
{
    TIME_UPDATE_FAILED = 0,
    TIME_UPDATE_OK = 1,
    TIME_UPDATE_PENDING = 2,
} TimeUpdateState;

typedef enum
{
    TM_INIT = 0,
    TM_INITIAL_SYNC = 1,
    TM_NORMAL = 2,
    TM_SYNC_OVERDUE = 3,
    TM_SYNC_TIMEOUT = 4,
    TM_SETUP_FAILED = 5,
} TimeManagerState;

class TimeManager
{
#define NTP_MAX_UPDATE_TIME_US (5 * 1000 * 1000) // 5000ms max update time

public:
    // constructors
    TimeManager();
    TimeManager(const char *tz,
                const char *ntp_server,
                bool (*is_wifi_connected)(void),
                uint32 ntp_max_offline_time_s,
                UDPLogger *logger);

    // init
    void init();

    // callback
    void time_set_cb(void); // callback which is called when NTP time was set

    // ntp methods
    bool ntp_sync_successful(void) const; // was there a NTP sync once?
    bool ntp_sync_overdue(void);          // function to check if NTP sync is overdue
    bool ntp_sync_timeout(void);          // function to check if maximum time since last NTP sync has been reached
    TimeUpdateState get_time();           // main time update method, called in loop

    // getter for time values
    bool isdst(void) const; // true if summertime (daylight saving time)
    int day(void) const;
    int hour(void) const;
    int minute(void) const;
    int month(void) const;
    int year(void) const;
    struct tm time_info(void) const;

    // getter
    TimeManagerState tm_state(void) const; // get current state

    // logging
    void log_time() const;                    // log _time_info
    void log_time(struct tm time_info) const; // log argument time_info

private:
    void _set_up_ntp(void);           // set up NTP server
    bool (*_is_wifi_connected)(void); // function to check if wifi is connected

    const char *_ntp_server = "pool.ntp.org";           // ntp server address
    const char *_tz;                                    // timezone
    struct tm _time_info = {0, 0, 0, 0, 0, 0, 0, 0, 0}; // structure tm holds time information
    time_t _now = 0;                                    // local time value
    time_t _ntp_sync_timestamp_s = 0;                   // timestamp of last successful ntp sync
    TimeManagerState _tm_state = TM_INIT;               // Main state
    UDPLogger *_logger;                                 // logger instance
    uint32 _ntp_max_offline_time_s;                     // maximum time in seconds which is considered ok since last NTP update
};

#endif /* TIME_MANAGER_H */