better time zone handling

FamilyPlanner.ino

@@ -59,7 +59,7 @@ const uint8_t *digits[10] = { image_data_icon_digit_0, image_data_icon_digit_1,
 char *ssid = "Freifunk";
 char *pass = "";
 char *calendarURL = "https://mail.unitas-network.de/mergedCalendars.json";
-int timeZone = 2;
+char *timeZone = "CET-1CEST,M3.5.0/02,M10.5.0/03";
 
 //Set to 1 to flip the screen 180 degrees
 #define ROTATION 3
@@ -98,9 +98,8 @@ void setup() {
     display.load1b();
 
     //Update data
-//    if (timeDigits[0]+timeDigits[1]+timeDigits[2]+timeDigits[3] == 0) {
     if ((timeDigits[1] == 5) && (timeDigits[0] == 9)) {
-        network.begin();                                              // every midnight set the time from internet
+        network.begin();                                              // every hour set the time from internet
         network.off();
         networking = true;
     }

Network.cpp

@@ -34,15 +34,13 @@ void Network::begin()
 // Gets time from ntp server
 void Network::getTime(int *timeDigits)
 {
-    // Get seconds since 1.1.1970.
-    time_t nowSecs = time(nullptr);
-
-    // Used to store time
     struct tm timeinfo;
-    gmtime_r(&nowSecs, &timeinfo);
 
-    // Setting time string timezone (Better defined modulo, in case timezone makes hours to go below 0)
-    timeinfo.tm_hour = ((timeinfo.tm_hour + timeZone) % 24 + 24) %24;
+    setenv("TZ", timeZone, 1);
+    tzset();
+
+    time_t nowSecs = time(nullptr);
+    localtime_r(&nowSecs, &timeinfo);
 
     // fill in the digits
     timeDigits[0] = timeinfo.tm_min % 10;    //minutes (units)

Network.h

@@ -4,7 +4,7 @@
 #include <WiFiClientSecure.h>
 
 // To get vars from main file
-extern int timeZone;
+extern char *timeZone;
 extern char calName[5][31];
 extern char calStart[5][26];
 extern char calTitle[5][81];