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package Log::Log4perl::Config::PropertyConfigurator;
use Log::Log4perl::Config::BaseConfigurator;

use warnings;
use strict;

our @ISA = qw(Log::Log4perl::Config::BaseConfigurator);

our %NOT_A_MULT_VALUE = map { $_ => 1 }
    qw(conversionpattern);

#poor man's export
*eval_if_perl = \&Log::Log4perl::Config::eval_if_perl;
*compile_if_perl = \&Log::Log4perl::Config::compile_if_perl;
*unlog4j      = \&Log::Log4perl::Config::unlog4j;

use constant _INTERNAL_DEBUG => 0;

our $COMMENT_REGEX = qr/[#;!]/;

################################################
sub parse {
################################################
    my($self, $newtext) = @_;

    $self->text($newtext) if defined $newtext;

    my $text = $self->{text};

    die "Config parser has nothing to parse" unless defined $text;

    my $data = {};
    my %var_subst = ();

    while (@$text) {
        local $_ = shift @$text;
        s/^\s*$COMMENT_REGEX.*//;
        next unless /\S/;
    
        my @parts = ();

        while (/(.+?)\\\s*$/) {
            my $prev = $1;
            my $next = shift(@$text);
            $next =~ s/^ +//g;  #leading spaces
            $next =~ s/^$COMMENT_REGEX.*//;
            $_ = $prev. $next;
            chomp;
        }

        if(my($key, $val) = /(\S+?)\s*=\s*(.*)/) {

            my $key_org = $key;

            $val =~ s/\s+$//;

                # Everything could potentially be a variable assignment
            $var_subst{$key} = $val;

                # Substitute any variables
            $val =~ s/\$\{(.*?)\}/
                      Log::Log4perl::Config::var_subst($1, \%var_subst)/gex;

            $key = unlog4j($key);

            my $how_deep = 0;
            my $ptr = $data;
            for my $part (split /\.|::/, $key) {
                push @parts, $part;
                $ptr->{$part} = {} unless exists $ptr->{$part};
                $ptr = $ptr->{$part};
                ++$how_deep;
            }

            #here's where we deal with turning multiple values like this:
            # log4j.appender.jabbender.to = him@a.jabber.server
            # log4j.appender.jabbender.to = her@a.jabber.server
            #into an arrayref like this:
            #to => { value => 
            #       ["him\@a.jabber.server", "her\@a.jabber.server"] },
            # 
            # This only is allowed for properties of appenders
            # not listed in %NOT_A_MULT_VALUE (see top of file).
            if (exists $ptr->{value} && 
                $how_deep > 2 &&
                defined $parts[0] && lc($parts[0]) eq "appender" && 
                defined $parts[2] && ! exists $NOT_A_MULT_VALUE{lc($parts[2])}
               ) {
                if (ref ($ptr->{value}) ne 'ARRAY') {
                    my $temp = $ptr->{value};
                    $ptr->{value} = [];
                    push (@{$ptr->{value}}, $temp);
                }
                push (@{$ptr->{value}}, $val);
            }else{
                if(defined $ptr->{value}) {
                    if(! $Log::Log4perl::Logger::NO_STRICT) {
                        die "$key_org redefined";
                    }
                }
                $ptr->{value} = $val;
            }
        }
    }
    $self->{data} = $data;
    return $data;
}

################################################
sub value {
################################################
  my($self, $path) = @_;

  $path = unlog4j($path);

  my @p = split /::/, $path;

  my $found = 0;
  my $r = $self->{data};

  while (my $n = shift @p) {
      if (exists $r->{$n}) {
          $r = $r->{$n};
          $found = 1;
      } else {
          $found = 0;
      }
  }

  if($found and exists $r->{value}) {
      return $r->{value};
  } else {
      return undef;
  }
}

1;

__END__

=encoding utf8

=head1 NAME

Log::Log4perl::Config::PropertyConfigurator - reads properties file

=head1 SYNOPSIS

    # This class is used internally by Log::Log4perl

    use Log::Log4perl::Config::PropertyConfigurator;

    my $conf = Log::Log4perl::Config::PropertyConfigurator->new();
    $conf->file("l4p.conf");
    $conf->parse(); # will die() on error

    my $value = $conf->value("log4perl.appender.LOGFILE.filename");
   
    if(defined $value) {
        printf("The appender's file name is $value\n");
    } else {
        printf("The appender's file name is not defined.\n");
    }

=head1 DESCRIPTION

Initializes log4perl from a properties file, stuff like

    log4j.category.a.b.c.d = WARN, A1
    log4j.category.a.b = INFO, A1

It also understands variable substitution, the following
configuration is equivalent to the previous one:

    settings = WARN, A1
    log4j.category.a.b.c.d = ${settings}
    log4j.category.a.b = INFO, A1

=head1 SEE ALSO

Log::Log4perl::Config

Log::Log4perl::Config::BaseConfigurator

Log::Log4perl::Config::DOMConfigurator

Log::Log4perl::Config::LDAPConfigurator (tbd!)

=head1 LICENSE

Copyright 2002-2013 by Mike Schilli E<lt>m@perlmeister.comE<gt> 
and Kevin Goess E<lt>cpan@goess.orgE<gt>.

This library is free software; you can redistribute it and/or modify
it under the same terms as Perl itself. 

=head1 AUTHOR

Please contribute patches to the project on Github:

    http://github.com/mschilli/log4perl

Send bug reports or requests for enhancements to the authors via our

MAILING LIST (questions, bug reports, suggestions/patches): 
log4perl-devel@lists.sourceforge.net

Authors (please contact them via the list above, not directly):
Mike Schilli <m@perlmeister.com>,
Kevin Goess <cpan@goess.org>

Contributors (in alphabetical order):
Ateeq Altaf, Cory Bennett, Jens Berthold, Jeremy Bopp, Hutton
Davidson, Chris R. Donnelly, Matisse Enzer, Hugh Esco, Anthony
Foiani, James FitzGibbon, Carl Franks, Dennis Gregorovic, Andy
Grundman, Paul Harrington, Alexander Hartmaier  David Hull, 
Robert Jacobson, Jason Kohles, Jeff Macdonald, Markus Peter, 
Brett Rann, Peter Rabbitson, Erik Selberg, Aaron Straup Cope, 
Lars Thegler, David Viner, Mac Yang.