# Selima Website Content Management System
# Server.pm: The server software identifiers.

#  Copyright (c) 2004-2018 imacat.
#
#  Licensed under the Apache License, Version 2.0 (the "License");
#  you may not use this file except in compliance with the License.
#  You may obtain a copy of the License at
#
#      http://www.apache.org/licenses/LICENSE-2.0
#
#  Unless required by applicable law or agreed to in writing, software
#  distributed under the License is distributed on an "AS IS" BASIS,
#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
#  See the License for the specific language governing permissions and
#  limitations under the License.

# Author: imacat <imacat@mail.imacat.idv.tw>
# First written: 2004-09-12

package Selima::Server;
use 5.008;
use strict;
use warnings;
use base qw(Exporter);
use vars qw(@EXPORT @EXPORT_OK);
BEGIN {
@EXPORT = qw(is_apache is_iis);
@EXPORT_OK = @EXPORT;
# Prototype declaration
sub is_apache();
sub is_iis();
}

use Selima::DataVars qw(:env);

# The result never changes in any circumstances
use vars qw($IS_APACHE $IS_IIS);
undef $IS_APACHE;
undef $IS_IIS;

# is_apache: If this server is Apache
sub is_apache() {
    # Checked before
    return $IS_APACHE if defined $IS_APACHE;
    # mod_perl always run on Apache
    return ($IS_APACHE = 1) if $IS_MODPERL;
    # Check from SERVER_SOFTWARE
    return ($IS_APACHE = ($ENV{"SERVER_SOFTWARE"} =~ /^Apache\b/? 1: 0));
}

# is_iis: If this server is Microsoft-IIS
sub is_iis() {
    # Checked before
    return $IS_IIS if defined $IS_IIS;
    # mod_perl never run on Microsoft-IIS
    return ($IS_IIS = 0) if $IS_MODPERL;
    # Check from SERVER_SOFTWARE
    return ($IS_IIS = ($ENV{"SERVER_SOFTWARE"} =~ /^Microsoft-(?:IIS|PWS)\b/? 1: 0));
}

return 1;