#!/usr/bin/env perl
# list-config - List one or all config directives for Webmin or a specific
# module.
use strict;
use warnings;

BEGIN { $Pod::Usage::Formatter = 'Pod::Text::Color'; }
use 5.010; # Version in CentOS 6

use Getopt::Long qw(:config permute pass_through);
use Pod::Usage;
use Term::ANSIColor qw(:constants);

sub main {
    my %opt;
    GetOptions(
        'help|h' => \$opt{'help'},
        'config|c=s' => \$opt{'config'},
        'module|m=s' => \$opt{'module'},
        'option|o=s' => \$opt{'option'},
        'describe|d' => \$opt{'describe'}
    );
    pod2usage(0) if ( $opt{'help'} );

    $opt{'config'} ||= "/etc/webmin";

    list_config( \%opt );
    
    return 0;
}
exit main( \@ARGV ) if !caller(0);

sub list_config {
    my ($optref) = @_;

    my @config_lines;
    # Module or root-level config?
    if ($optref->{'module'}) {
        # Read the module config file
        @config_lines = load_config($optref->{'config'}, "$optref->{'module'}/config");
    } else {
        @config_lines = load_config($optref->{'config'}, "miniserv.conf");
    }

    # Display either a single item or the whole thing
    if ($optref->{'option'}) {
        # Show one item
        my $value;
        if ($optref->{'module'} and $optref->{'describe'}) {
            $value = get_description($optref);
        } else {
            $value = get_config_value($optref->{'option'}, \@config_lines)
                || die RED, "Unable to retrieve value of $optref->{'option'}", RESET;
        }
        say $value;
    } else {
        # Show all
        if ($optref->{'module'} and $optref->{'describe'}) {
            @config_lines = get_description($optref);
        } elsif ($optref->{'describe'}) {
            die RED, "--describe only available for modules", RESET;
        }
        say for @config_lines;
    }
}

sub load_config {
    my ($config_dir, $file_path) = @_;

    my @config_lines;
    if (-e "$config_dir/$file_path") {
        open my $fh, '<', "$config_dir/$file_path"
            || die RED, "Unable to open $config_dir/$file_path", RESET;
        chomp(@config_lines = <$fh>);
        close $fh;
    } else {
        die RED, "Unable to open $config_dir/$file_path.", RESET;
    }
    return @config_lines;
}

# get_config_var
# Read the file at $config and return the value of key
sub get_config_value {
    my ($key, $config_lines_ref) = @_;
    my $value;
    
    foreach my $line (@$config_lines_ref) {
        if ($line =~ /^${key}=(.*)/) {
            $value = $1;
        }
    }

    return $value;
}

# get_description
# Return a description of one or more options from config.info
sub get_description {
    my ($optref) = @_;

    my $root = root($optref->{'config'});
    my $config_info = "$root/$optref->{'module'}/config.info";
    my $key = $optref->{'option'};

    open my $fh, '<', $config_info
      or die RED, "Unable to open $config_info", RESET;
    if ($optref->{'option'}) {
        my $found = 0;
        # return one description
        while (<$fh>) {
            if (/^${key}=([^,]*)/) {
                $found++;
                return "$key - $1";
            }
        }
        $found or die RED, "Unrecognized option $key", RESET;
    } else {
        my $found;
        # return all descriptions
        my @lines;
        while (<$fh>) {
            if (/^(.*)=([^,]*)/) {
                push (@lines, "$1 - $2");
                $found++;
            }
        }
        $found or die RED, "No options found for module $optref->{'module'}";
        return @lines;
    }
}

sub root {
    my ($config) = @_;
    open(my $CONF, "<", "$config/miniserv.conf") || die RED,
        "Failed to open $config/miniserv.conf", RESET;
    my $root;
    while (<$CONF>) {
        if (/^root=(.*)/) {
            $root = $1;
        }
    }
    close($CONF);
    # Does the Webmin root exist?
    if ( $root ) {
        die "$root is not a directory. Is --config correct?" unless (-d $root);
    } else {
        # Try to guess where Webmin lives, since config file didn't know.
        die "Unable to determine Webmin installation directory from $ENV{'WEBMIN_CONFIG'}";
    }

    return $root;
}

1;

=pod

=head1 NAME

list-config

=head1 DESCRIPTION

List one or all configuration directives for C<miniserv.conf> or a module C<config> file.

=head1 SYNOPSIS

webmin list-config [options]

=head1 OPTIONS

=over

=item --help, -h

Print this usage summary and exit.

=item --config, -c

Specify the full path to the Webmin configuration directory. Defaults to
C</etc/webmin>

=item --module, -m

Specify which module configuration to display. If none given, configuration will be assumed to be the Webmin core configuration (/etc/webmin/miniserv.conf).

=item --option, -o

Specify a single option to display. By default, the entire configuration file will be displayed. If this option is given, only the option specified will be shown.

=item --describe, -d

Display the description of the option from the module C<config.info> file, instead of it's current value. This option is only available for modules, as miniserv.conf does not have a config.info.



=back

=head1 LICENSE AND COPYRIGHT

 Copyright 2018 Jamie Cameron <jcameron@webmin.com>
                Joe Cooper <joe@virtualmin.com>