#ifndef NTPCLIENTPLUS_H
#define NTPCLIENTPLUS_H

#include <Arduino.h>
#include <WiFiUdp.h>

#define UNIX_TIMESTAMP_1900 2208988800UL // careful: positive value
#define NTP_PACKET_SIZE 48
#define NTP_DEFAULT_LOCAL_PORT 1337
#define MAX_NTP_CONN_TRIES 50       // 50 * NTP_RECEIVE_WAIT_TIME_MS => 500ms
#define NTP_RECEIVE_WAIT_TIME_MS 10 // 10ms

typedef enum
{
    NTP_UPDATE_TIMEOUT = -1,
    NTP_UPDATE_SUCCESS = 0,
    NTP_UPDATE_DIFFTOOHIGH = 1,
    NTP_UPDATE_TIME_INVALID = 2
} ntp_return_values;

/**
 * @brief Own NTP Client library for Arduino with code from:
 * - https://github.com/arduino-libraries/NTPClient
 * - SPS&Technik - Projekt WordClock v1.02
 *
 */
class NTPClientPlus
{
public:
    NTPClientPlus(UDP &udp, const char *poolServerName, int utcx, bool _swChange);
    void setupNTPClient();
    int updateNTP();
    void end();
    void setTimeOffset(int timeOffset);
    void setPoolServerName(const char *poolServerName);
    unsigned long getSecsSince1900() const;
    unsigned long getEpochTime() const;
    int getHours24() const;
    int getHours12() const;
    int getMinutes() const;
    int getSeconds() const;
    String getFormattedTime() const;
    String getFormattedDate();
    void calcDate();
    unsigned int getDayOfWeek();
    unsigned int getYear();
    bool isLeapYear(unsigned int year);
    int getMonth(int dayOfYear);
    long getTimeOffset();
    bool updateSWChange();

private:
    UDP *_udp;
    bool _udpSetup = false;

    bool _swChange = 1;
    const char *_poolServerName = "pool.ntp.org"; // Default time server
    int _utcx = 0;
    IPAddress _poolServerIP;
    long _timeOffset = 0;
    unsigned int _port = NTP_DEFAULT_LOCAL_PORT;

    unsigned long _updateInterval = 60000; // In ms

    unsigned long _currentEpoc = 0;   // In s
    unsigned long _lastUpdate = 0;    // In ms
    unsigned long _secsSince1900 = 0; // seconds since 1. Januar 1900, 00:00:00
    unsigned long _lastSecsSince1900 = 0;
    unsigned int _dateYear = 0;
    unsigned int _dateMonth = 0;
    unsigned int _dateDay = 0;
    unsigned int _dayOfWeek = 0;

    unsigned char _packetBuffer[NTP_PACKET_SIZE] = {0};
    void sendNTPPacket();
    void setSummertime(bool summertime);

    static const unsigned long secondperday = 86400;
    static const unsigned long secondperhour = 3600;
    static const unsigned long secondperminute = 60;
    static const unsigned long minuteperhour = 60;
    static const unsigned long millisecondpersecond = 1000;

    // number of days in months
    unsigned int daysInMonth[13] = {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
};

void wait(unsigned long time);

#endif /* NTPCLIENTPLUS_H */