use strict;
use warnings;

use DateTime::TimeZone::Local;
use File::Basename qw( basename );
use File::Spec;
use Sys::Hostname qw( hostname );
use Test::More;

use lib File::Spec->catdir( File::Spec->curdir, 't' );

BEGIN { require 'check_datetime_version.pl' }

unless ( $^O =~ /win32/i )
{
    plan skip_all => 'These tests only run on Windows';
}

my $Registry;
eval <<'EOF';
use DateTime::TimeZone::Local::Win32;
use Win32::TieRegistry ( TiedRef => \$Registry, Delimiter => q{/} );
EOF

if ($@)
{
    plan skip_all => 'These tests require Win32::TieRegistry';
}

my $tzi_key =
    $Registry->Open
        ( 'LMachine/SYSTEM/CurrentControlSet/Control/TimeZoneInformation/',
          { Access => Win32::TieRegistry::KEY_READ() | Win32::TieRegistry::KEY_WRITE() }
        );

plan skip_all => 'These tests require write access to TimeZoneInformation registry key'
    unless $tzi_key;

my @win_tz_names = windows_tz_names();

plan tests => @win_tz_names + 6;


my $WindowsTZKey;

{
    foreach my $win_tz_name (@win_tz_names)
    {
        set_and_test_windows_tz( $win_tz_name, undef, $tzi_key );
    }

    # We test these explicitly because we want to make sure that at
    # least a few known names do work, rather than just relying on
    # looping through a list.
    for my $pair ( [ 'Eastern Standard Time', 'America/New_York' ],
                   [ 'Dateline Standard Time', 'Pacific/Majuro' ],
                   [ 'Israel Standard Time', 'Asia/Jerusalem' ],
                 )
    {
        set_and_test_windows_tz( @{ $pair }, $tzi_key );
    }
}


sub windows_tz_names
{
    $WindowsTZKey =
        $Registry->Open( 'LMachine/SOFTWARE/Microsoft/Windows NT/CurrentVersion/Time Zones/',
                         { Access => Win32::TieRegistry::KEY_READ() }
                       );

    $WindowsTZKey ||=
        $Registry->Open( 'LMachine/SOFTWARE/Microsoft/Windows/CurrentVersion/Time Zones/',
                         { Access => Win32::TieRegistry::KEY_READ() }
                       );

    return unless $WindowsTZKey;

    return $WindowsTZKey->SubKeyNames();
}

sub set_and_test_windows_tz
{
    my $windows_tz_name = shift;
    my $olson_name      = shift;
    my $tzi_key         = shift;

    if ( defined $tzi_key
         && defined $tzi_key->{'/TimeZoneKeyName'}
         && $tzi_key->{'/TimeZoneKeyName'} ne '' )
    {
        local $tzi_key->{'/TimeZoneKeyName'} = $windows_tz_name;

        test_windows_zone( $windows_tz_name, $olson_name );
    }
    else
    {
        local $tzi_key->{'/StandardName'} =
            ( $WindowsTZKey->{ $windows_tz_name . q{/} }
              ? $WindowsTZKey->{ $windows_tz_name . '/Std' }
              : 'MAKE BELIEVE VALUE'
            );

        test_windows_zone( $windows_tz_name, $olson_name );
    }
}

sub test_windows_zone
{
    my $windows_tz_name = shift;
    my $olson_name      = shift;

    my $tz = DateTime::TimeZone::Local::Win32->FromRegistry();

    ok( $tz && DateTime::TimeZone->is_valid_name( $tz->name() ),
        "$windows_tz_name - found valid Olson time zone from Windows" );

    if ( defined $olson_name )
    {
        my $desc =  "$windows_tz_name was mapped to $olson_name";
        if ($tz)
        {
            is( $tz->name(), $olson_name, $desc );
        }
        else
        {
            fail($desc);
        }
    }
}