/*F********************************************************************
* Arduino Timezone Library Copyright (C) 2018 by Jack Christensen and
licensed under GNU GPL v3.0, https://www.gnu.org/licenses/gpl.html
Arduino Timezone Library example sketch.
Self-adjusting clock for one time zone using an external real-time
clock, either a DS1307 or DS3231 (e.g. Chronodot).
Assumes the RTC is set to UTC.
TimeChangeRules can be hard-coded or read from EEPROM, see comments.
Check out the Chronodot at http://www.macetech.com/store/
Jack Christensen Aug 2012
**********************************************************************/
#include <DS1307RTC.h>   // https://github.com/PaulStoffregen/DS1307RTC
#include <Timezone.h>    // https://github.com/JChristensen/Timezone

//************************* DEFINES ************************************
#define  BAUD  9600

//************************* PROTOTYPES ************************************
void printDateTime( time_t t, const char *tz);

//************************* VARIABLES ************************************
// US CENTRAL Time Zone ( Chicago, Dallas )
TimeChangeRule Dst = { "DST", Second, Sun, Mar, 2, -300};// DST = UTC - 5 hrs
TimeChangeRule Cst = { "CST", First, Sun, Nov, 2, -360}; // CST = UTC - 6 hrs
Timezone myTZ( Cdt, Dst );
// If TimeChangeRules are already stored in EEPROM, comment out three
// lines above and uncomment line below.
//Timezone myTZ( 100 );        // ASSUMES RULES STORED AT EEPROM ADDRESS 100
TimeChangeRule *tcr;    // POINTER TO TIME CHANGE RULE, USE TO GET TZ ABBREV

/*F********************************************************************
*
**********************************************************************/
void 
setup()
{
    Serial.begin( BAUD );
    setSyncProvider( RTC.get);                          // GET TIME FROM RTC
    if(timeStatus()!= timeSet)
        Serial.println( "Unable to sync with the RTC");
    else
        Serial.println( "RTC has set the system time");
}
/*F********************************************************************
*
**********************************************************************/
void 
loop()
{
    time_t utc = now();
    time_t local = myTZ.toLocal( utc, &tcr );
    Serial.println();
    printDateTime( utc, "UTC");
    printDateTime( local, tcr->abbrev);
    delay( 10000 );
}
/*F********************************************************************
* FORMAT AND PRINT A TIME_T VALUE, WITH A TIME ZONE APPENDED
**********************************************************************/
void 
printDateTime( time_t t, const char *tz)
{
    char buf[32];
    char m[4];          // MONTH STRING (DateStrings.cpp USES SHARED BUFFER)
    strcpy( m, monthShortStr(month(t)));
    sprintf( buf, "%.2d:%.2d:%.2d %s %.2d %s %d %s", hour(t), minute(t)
        , second(t), dayShortStr( weekday(t)), day(t), m, year(t), tz);
    Serial.println( buf );
}