#! /usr/bin/perl
# -----------------------------------------------------------------------------
# Copyright (c) 2006, 2007 - OpenSLX GmbH
#
# This program is free software distributed under the GPL version 2.
# See http://openslx.org/COPYING
#
# If you have any feedback please consult http://openslx.org/feedback and
# send your suggestions, praise, or complaints to feedback@openslx.org
#
# General information about OpenSLX can be found at http://openslx.org/
# -----------------------------------------------------------------------------
# slxsettings
#    - OpenSLX-script to show & change local settings
# -----------------------------------------------------------------------------
use strict;
use warnings;

my $abstract = q[
slxsettings
    This script can be used to show or change the local settings for OpenSLX.

    Any cmdline-argument passed to this script will change the local OpenSLX
    settings file (usually /etc/opt/openslx/settings).

    If you invoke the script without any arguments, it will print the current
    settings and exit.

    Please use the --man option in order to read the full manual.
];

# add the lib-folder and the folder this script lives in to perl's search
# path for modules:
use FindBin;
use lib "$FindBin::RealBin/../lib";
use lib "$FindBin::RealBin";
# development path to config-db stuff

use Config::General;
use Getopt::Long qw(:config pass_through);
use Pod::Usage;

use OpenSLX::Basics;
use OpenSLX::Utils;

my (@reset, %givenSettings, %option);

GetOptions(
    'quiet'   => \$option{quiet},
    'help|?'  => \$option{helpReq},
    'man'     => \$option{manReq},
    'version' => \$option{versionReq},
);
pod2usage(-msg => $abstract, -verbose => 0, -exitval => 1) if $option{helpReq};
pod2usage(-verbose => 2) if $option{manReq};
if ($option{versionReq}) {
    system('slxversion');
    exit 1;
}

if ($> != 0) {
    die _tr("Sorry, this script can only be executed by the superuser!\n");
}

openslxInit() or pod2usage(2);

# some settings must match a certain pattern:
my %configPattern = (
    'db-type' => '(SQLite|mysql)',
);

# the remaining cmdline arguments are set or reset actions, each followed
# by a single argument:
while (scalar @ARGV) {
    my $action = shift || '';
    my $arg    = shift || '';
    if ($action eq 'set') {
        if ($arg !~ m[^([-\w]+)=(.+)$]) {
            die _tr(
                "set-argument '%s' has unknown format, expected '<key>=<value>!'",
                $arg
            );
        }
        $givenSettings{$1} = $2;
    }
    elsif ($action eq 'reset') {
        push @reset, $arg;
    }
    else {
        die _tr(unshiftHereDoc(<<'        END-OF-HERE'), $arg, $0);
            action '%s' is not understood! Known actions are:
                set
                reset
            Try '%s --help' for more info.
        END-OF-HERE
    }
}

# fetch current content of local settings file...
my $fileName = "$openslxConfig{'config-path'}/settings";
if (!-e $fileName) {
    # create empty default settings file with tight mode (root-only access)
    # [I know this isn't *secure* as such, but it's still better than nothing]
    slxsystem("touch $fileName && chmod 0600 $fileName");
}
my $configObj = Config::General->new(
    -ConfigFile     => $fileName, 
    -SplitDelimiter => '\s*=\s*',
    -SplitPolicy    => 'custom',
    -StoreDelimiter => '=',
);
my %settings = $configObj->getall();

my %changed;

# ...set new values...
foreach my $key (keys %givenSettings) {
    my $value = $givenSettings{$key};
    next if !defined $value;
    if (!exists $openslxConfig{$key}) {
        die _tr("option '%s' is not known!", $key);
    }
    if ($key =~ m{^(base-path|config-path)$}) {
        die _tr("option '%s' is fixed!", $key);
    }
    if (exists $configPattern{$key} && $value !~ m{$configPattern{$key}}) {
        die _tr(
            "option '%s' must match pattern '%s'!", $key, $configPattern{$key}
        );
    }

    vlog(0, _tr("setting %s to '%s'", $key, $value)) unless $option{quiet};
    my $externalKey = externalKeyFor($key);
    if (!exists $settings{$externalKey} || $settings{$externalKey} ne $value) {
        $settings{$externalKey} = $value;
    }
    $changed{$key}++;
}

# reset specified keys to fall back to default:
foreach my $key (@reset) {
    my $externalKey = externalKeyFor($key);
    if (exists $settings{$externalKey}) {
        delete $settings{$externalKey};
        vlog(0,
            _tr("removing option '%s' from local settings", $key))
              unless $option{quiet};
    } else {
        vlog(0,
            _tr("option '%s' didn't exist in local settings!", $key))
              unless $option{quiet};
    }
    $changed{$key}++;
}

# ... and write local settings file if necessary
if (keys %changed) {
    $configObj->save_file($fileName, \%settings);

    openslxInit();

    foreach my $key (keys %changed) {
        changedHandler($key, $openslxConfig{$key});
    }
}

if (!keys %changed) {
    print _tr("paths fixed at installation time:\n");
    print qq[\tbase-path='$openslxConfig{'base-path'}'\n];
    print qq[\tconfig-path='$openslxConfig{'config-path'}'\n];
    my $text =
      keys %changed
      ? "resulting base settings (cmdline options):\n"
      : "current base settings (cmdline options):\n";
    print $text;
    my @baseSettings = grep { exists $cmdlineConfig{$_} } keys %openslxConfig;
    foreach my $key (sort @baseSettings) {
        my $val = $openslxConfig{$key} || '';
        print qq[\t$key='$val'\n];
    }
    print _tr("extended settings:\n");
    my @extSettings = grep { !exists $cmdlineConfig{$_} } keys %openslxConfig;
    foreach my $key (sort @extSettings) {
        next if $key =~ m[^(base-path|config-path)$];
        my $val = $openslxConfig{$key};
        if (defined $val) {
            print qq[\t$key='$val'\n];
        }
        else {
            print qq[\t$key=<unset>\n];
        }
    }
}

sub externalKeyFor
{
    my $key = shift;

    $key =~ tr[-][_];
    return "SLX_" . uc($key);
}

sub changedHandler
{
    my $key   = shift;
    my $value = shift;

    # invoke a key-specific change handler if it exists:
    $key =~ tr[-][_];

    # we do the following function call in an eval as that function may simply
    # not exist:
    eval {
        no strict 'refs';        ## no critic (ProhibitNoStrict)
        "${key}_changed_handler"->();
    };
    
    return;
}

sub private_path_changed_handler
{
    # create the default config folders (for default system only):
    require OpenSLX::ConfigFolder;
    OpenSLX::ConfigFolder::createConfigFolderForDefaultSystem();
    OpenSLX::ConfigFolder::createConfigFolderForDefaultVendorOS();

    return;
}

=head1 NAME

slxsettings - OpenSLX-script to show & change local settings

=head1 SYNOPSIS

slxsettings [options] [action ...]

=head3 Script Actions

      set <option-name=value>    sets the option to the given value
      reset <option-name>        resets the given option to its default

=head3 List of Known Option Names

      db-name=<string>           name of database
      db-spec=<string>           full DBI-specification of database
      db-type=<string>           type of database to connect to
      locale=<string>            locale to use for translations
      log-level=<int>            level of logging verbosity (0-3)
      logfile=<string>           file to write logging output to
      private-path=<string>      path to private data
      public-path=<string>       path to public (client-accesible) data
      temp-path=<string>         path to temporary data

=head3 General Options

      --help                     brief help message
      --man                      full documentation
      --quiet                    do not print anything
      --version                  show version

=head3 Actions

=over 8

=item B<<     set <openslx-option>=<value> >>

sets the specified option to the given value

=item B<<     reset <setting> >>

removes the given setting from the local settings (resets it to its default
value)

=back

=head1 DESCRIPTION

B<slxsettings> can be used to show or change the local settings for OpenSLX.

Any cmdline-argument passed to this script will change the local OpenSLX
settings file (usually /etc/opt/openslx/settings).

If you invoke the script without any arguments, it will print the current
settings and exit.

=head1 OPTIONS

=head3 Known Option Names

=over 8

=item B<<     db-name=<string> >>

Gives the name of the database to connect to.

Default is $SLX_DB_NAME (usually C<openslx>).

=item B<<     db-spec=<string> >>

Gives the full DBI-specification of database to connect to. Content depends
on the db-type.

Default is $SLX_DB_SPEC (usually empty as it will be built automatically).

=item B<<     db-type=<string> >>

Sets the type of database to connect to (SQLite, mysql, ...).

Default $SLX_DB_TYPE (usually C<SQLite>).

=item B<<     locale=<string> >>

Sets the locale to use for translations.

Defaults to the system's standard locale.

=item B<<     logfile=<string> >>

Specifies a file where logging output will be written to.

Default is to log to STDERR.

=item B<<     private-path=<string> >>

Sets path to private data, where the config-db, vendor_oses and configurational
extensions will be stored.

Default is $SLX_PRIVATE_PATH (usually F</var/opt/openslx>.

=item B<<     public-path=<string> >>

Sets path to public (client-accesible) data.

Default is $SLX_PUBLIC_PATH (usually F</srv/openslx>.

=item B<<     temp-path=<string> >>

Sets path to temporary data.

Default is $SLX_TEMP_PATH (usually F</tmp>.

=item B<<     log-level=<int> >>

Sets the level of logging verbosity (0-3).
Prints additional output for debugging. N is a number between 0 and 3. Level
1 provides more information than the default, while 2 provides traces. With
level 3 you get extreme debug output, e.g. database commands are printed.

Default is $SLX_VERBOSE_LEVEL (usually 0, no logging).

=back

=head3 General Options

=over 8

=item B<    --help>

Prints a brief help message and exits.

=item B<    --man>

Prints the manual page and exits.

=item B<    --quiet>

Runs the script without printing anything.

=item B<    --version>

Prints the version and exits.

=back

=head1 SEE ALSO

slxos-setup, slxos-export, slxconfig, slxconfig-demuxer

=cut