#!/bin/bash
#
# tzset-from-unicode.org
#
# Fetch XML file containing mapping of Windows timezone keynames and countries
# per ISO 3166-1 to POSIX timezones from unicode.org.
#
# Create the table file as required by tzset.c.
#

ZONES_FILE="https://raw.githubusercontent.com/unicode-org/cldr/master/common/supplemental/windowsZones.xml"

echo "/*"
echo "   This file gets auto-generated by the script tzmap-from-unicode.org via"
echo "   a Makefile rule.  To regenerate the file, just call 'make tzmap'.  It"
echo "   fetches the file"
echo ""
echo "     ${ZONES_FILE}"
echo ""
echo "   using wget and converts it into the tzmap table required by tzget.c."
echo "   Regenerating might be necessary on a regular basis..."
echo ""
echo "   This table maps Windows timezone keynames and countries per ISO 3166-1 to"
echo "   POSIX-compatible timezone IDs."
echo ""
echo "   The mapping from unicode.org is just a bit incomplete.  It doesn't contain"
echo "   some (deprecated) timezones available since Windows 8.1:"
echo ""
echo "    Mid-Atlantic Standard Time"
echo "    Kamchatka Standard Time"
echo ""
echo "  as well as a few combinations which got a new Windows timezone name"
echo "  but may still be in use somewhere..."
echo ""
echo "    E. Europe Standard Time/CY"
echo "    Eastern Standard Time/TC"
echo "    Egypt Standard Time/PS"
echo "    Greenwich Standard Time/EH"
echo "    Hawaiian Standard Time/TK"
echo "    Kaliningrad Standard Time/BY"
echo "    SA Pacific Standard Time/HT "
echo "    South Africa Standard Time/LY"
echo "*/"
echo ""
echo "struct"
echo "{"
echo "  PCWSTR win_tzkey;"
echo "  PCWSTR country;"
echo "  PCWSTR posix_tzid;"
echo "} const tzmap[] ="
echo "{"
wget -O - "${ZONES_FILE}" | \
{
  sed -n -e 's#territory="001"#territory=""#
	     s#Asia/Calcutta#Asia/Kolkata#
	     s#.*mapZone other=\("[^"]*"\) territory=\("[^"]*"\) type=\("[^"]*"\).*#  { L\1, L\2, L\3 },#p'
  echo '  { L"E. Europe Standard Time", L"CY", L"Asia/Nicosia" },'
  echo '  { L"Eastern Standard Time", L"TC", L"America/Grand_Turk" },'
  echo '  { L"Egypt Standard Time", L"PS", L"Asia/Gaza Asia/Hebron" },'
  echo '  { L"Greenwich Standard Time", L"EH", L"Africa/El_Aaiun" },'
  echo '  { L"Kaliningrad Standard Time", L"BY", L"Europe/Minsk" },'
  echo '  { L"Kamchatka Standard Time", L"", L"Asia/Kamchatka" },'
  echo '  { L"Hawaiian Standard Time", L"TK", L"Pacific/Fakaofo" },'
  echo '  { L"Mid-Atlantic Standard Time", L"", L"Atlantic/South_Georgia" },'
  echo '  { L"SA Pacific Standard Time", L"HT", L"America/Port-au-Prince" },'
  echo '  { L"South Africa Standard Time", L"LY", L"Africa/Tripoli" },'
} | LC_ALL=C sort -d
echo "};"
