# -*- perl -*-
#
#  Net::Server::MultiType - Net::Server personality
#
#  Copyright (C) 2001-2022
#
#    Paul Seamons <paul@seamons.com>
#
#  This package may be distributed under the terms of either the
#  GNU General Public License
#    or the
#  Perl Artistic License
#
#  All rights reserved.
#
################################################################

package Net::Server::MultiType;

use strict;
use base qw(Net::Server);

#sub net_server_type { shift->SUPER::net_server_type }; # not-needed

sub options {
    my $self = shift;
    my $ref  = $self->SUPER::options(@_);
    $ref->{'server_type'} = $self->{'server'}->{'server_type'} ||= [];
    return $ref;
}

sub default_server_type { 'Fork' }

sub run {
    my $self = ref($_[0]) ? shift() : shift->new;
    $self->{'server'}->{'_run_args'} = [@_ == 1 ? %{$_[0]} : @_];
    $self->_initialize;
    my $prop = $self->{'server'};

    if (!defined $prop->{'server_type'} || ! @{ $prop->{'server_type'} }) {
        if (my $ref = $self->can('default_server_type') && $self->default_server_type) {
            $prop->{'server_type'} = ref($ref) ? $ref : [$ref];
        }
    }
    foreach my $type (@{ $prop->{'server_type'} || []}) {
        next if $type eq 'MultiType';
        $type = ($type =~ /^(\w+)$/) ? $1 : next; # satisfy taint

        my $pkg = ($type =~ /::/) ? $type : "Net::Server::$type";
        (my $file = "$pkg.pm") =~ s{::}{/}g;
        eval { require $file };
        if ($@){
            warn "Couldn't become server type \"$pkg\" [$@]\n";
            next;
        }

        # handle items like HTTP and PSGI that aren't true Net::Server flavors, but themselves are MultiType
        if ($pkg->isa(__PACKAGE__)) {
            my $type = $self->default_server_type || 'Single';
            $type = ($type =~ /^(\w+)$/) ? $1 : next; # satisfy taint
            my $_pkg = ($type =~ /::/) ? $type : "Net::Server::$type";
            $prop->{'_recursive_multitype'} = $_pkg;
            (my $file = "$_pkg.pm") =~ s{::}{/}g;
            eval { require $file } or die "Trouble becoming server type $pkg while loading default package $_pkg: $@\n";
            die "Recursive inheritance - Package $pkg inherits from $_pkg.\n" if $_pkg->isa($pkg);
            no strict 'refs';
            @{"${pkg}::ISA"} = ($_pkg);
        }

        # kludgy - doesn't allow multiple Net::Server::MultiType servers within same process
        # but it is probably better than modifying our child's class for it
        @Net::Server::MultiType::ISA = ($pkg);
        last;
    }

    # now run as the new type of thingy
    # passing self, instead of package, doesn't instantiate a new object
    $self->SUPER::run(@_);
}

1;

__END__

=head1 NAME

Net::Server::MultiType - Net::Server personality

=head1 SYNOPSIS

    use base qw(Net::Server::MultiType);

    sub process_request {
        #...code...
    }

    my @types = qw(PreFork Fork Single);

    Net::Server::MultiType->run(server_type => \@types);

=head1 DESCRIPTION

Please read the pod on Net::Server first.  This module is a
personality, or extension, or sub class, of the Net::Server module.

This personality is intended to allow for easy use of multiple
Net::Server personalities.  Given a list of server types,
Net::Server::MultiType will require one at a time until it finds one
that is installed on the system.  It then adds that package to its
@ISA, thus inheriting the methods of that personality.

=head1 ARGUMENTS

In addition to the command line arguments of the Net::Server base
class, Net::Server::MultiType contains one other configurable
parameter.

    Key               Value            Default
    server_type       'server_type'    'Single'

=over 4

=item server_type

May be called many times to build up an array or possible
server_types.  At execution, Net::Server::MultiType will find the
first available one and then inherit the methods of that personality

=back

=head1 CONFIGURATION FILE

C<Net::Server::MultiType> allows for the use of a configuration file
to read in server parameters.  The format of this conf file is simple
key value pairs.  Comments and white space are ignored.

    #-------------- file test.conf --------------

    ### multi type info
    ### try PreFork first, then go to Single
    server_type PreFork
    server_type Single

    ### server information
    min_servers   20
    max_servers   80
    spare_servers 10

    max_requests  1000

    ### user and group to become
    user        somebody
    group       everybody

    ### logging ?
    log_file    /var/log/server.log
    log_level   3
    pid_file    /tmp/server.pid

    ### access control
    allow       .+\.(net|com)
    allow       domain\.com
    deny        a.+

    ### background the process?
    background  1

    ### ports to bind
    host        127.0.0.1
    port        localhost:20204
    port        20205

    ### reverse lookups ?
    # reverse_lookups on

    #-------------- file test.conf --------------

=head1 PROCESS FLOW

See L<Net::Server>

=head1 HOOKS

There are no additional hooks in Net::Server::MultiType.

=head1 TO DO

See L<Net::Server>

=head1 AUTHOR

Paul T. Seamons paul@seamons.com

=head1 SEE ALSO

Please see also
L<Net::Server::Fork>,
L<Net::Server::INET>,
L<Net::Server::PreFork>,
L<Net::Server::MultiType>,
L<Net::Server::Single>

=cut