added system independent German time support

[selfforum.git] / selfforum-cgi / shared / Time / German.pm

diff --git a/selfforum-cgi/shared/Time/German.pm b/selfforum-cgi/shared/Time/German.pm
new file mode 100644 (file)
index 0000000..52d7153
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+++ b/selfforum-cgi/shared/Time/German.pm
@@ -0,0 +1,118 @@
+package Time::German;
+
+################################################################################
+#                                                                              #
+# File:        shared/Time/German.pm                                           #
+#                                                                              #
+# Authors:     Andre Malo       <nd@o3media.de>, 2001-06-10                    #
+#                                                                              #
+# Description: determine time offset German Time <=> GMT (seconds)             #
+#                                                                              #
+################################################################################
+
+use strict;
+
+################################################################################
+#
+# Export
+#
+use base 'Exporter';
+@Time::German::EXPORT = qw(germantime);
+
+################################################################################
+#
+# german summertime 1980-1995 (ydays)
+#
+my %summertime = (
+  80 => [96, 271],
+  81 => [87, 269],
+  82 => [86, 268],
+  83 => [85, 267],
+  84 => [84, 273],
+  85 => [89, 271],
+  86 => [88, 270],
+  87 => [87, 269],
+  88 => [86, 268],
+  89 => [84, 266],
+  90 => [83, 272],
+  91 => [89, 271],
+  92 => [88, 270],
+  93 => [86, 268],
+  94 => [85, 267],
+  95 => [84, 266]
+);
+
+### germantime () ##############################################################
+#
+# like 'localtime', but system independent
+#
+# Params: $time - time since epoch (GMT)
+#
+# Return: same as localtime, but german time ;-)
+#
+sub germantime (;$) {
+  my $time = shift;
+  $time = time unless defined $time;
+
+  my ($hour,$mday,$mon,$year,$wday,$yday) = (gmtime($time))[qw(2 3 4 5 6 7)];
+  my $offset = 1;
+
+  # 1980 - 1995
+  #
+  if ($summertime{$year}) {
+    $offset++ if (
+      (
+        $yday >  $summertime{$year} -> [0]  and
+        $yday <  $summertime{$year} -> [1]
+      ) or
+      (
+        $yday == $summertime{$year} -> [0]  and
+        $hour >= 1
+      ) or
+      (
+        $yday == $summertime{$year} -> [1]  and
+        $hour <= 1
+      )
+    );
+  }
+
+  # > 1995
+  #
+  elsif ($year > 95) {
+    # determine last Sunday in March or October
+    #
+    my $limit = $mday + int((31-$mday)/7) * 7 - $wday if ($mon == 2 or $mon == 9);
+
+    $offset++ if (
+      (
+        $mon > 2          and
+        $mon < 9
+      ) or
+      (
+        $mon  == 2        and
+        (
+          $mday >  $limit  or
+          $mday == $limit and
+          $hour >= 1
+        )
+      ) or
+      (
+        $mon == 9         and
+        (
+          $mday <  $limit  or
+          $mday == $limit and
+          $hour <= 1
+        )
+      )
+    );
+  }
+
+  return gmtime($time + $offset * 3600);
+}
+
+# keep 'require' happy
+1;
+
+#
+#
+### end of Time::German ########################################################
\ No newline at end of file