# Copyright (c) 2008 - 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/
# -----------------------------------------------------------------------------
# BootEnvironment::Preboot.pm
#    - provides general preboot implementation of the BootEnvironment API.
# -----------------------------------------------------------------------------
package OpenSLX::BootEnvironment::Preboot;

use strict;
use warnings;

use base qw(OpenSLX::BootEnvironment::Base);

use Clone qw(clone);
use File::Basename;
use File::Path;

use OpenSLX::Basics;
use OpenSLX::ConfigDB qw(:support);
use OpenSLX::Utils;

sub initialize
{
    my $self   = shift;
    my $params = shift;
    
    return if !$self->SUPER::initialize($params);

    $self->{'original-path'} = "$openslxConfig{'public-path'}/preboot";
    $self->{'target-path'}   = "$openslxConfig{'public-path'}/preboot.new";

    $self->{'requires-default-client-config'} = 0;
        # we do not need a default.tgz since there's always an explicit client
    
    if (!$self->{'dry-run'}) {
        mkpath([$self->{'original-path'}]);
        rmtree($self->{'target-path'});
        mkpath("$self->{'target-path'}/client-config");
    }

    return 1;
}

sub writeBootloaderMenuFor
{
    my $self             = shift;
    my $client           = shift;
    my $externalClientID = shift;
    my $systemInfos      = shift || [];

    $self->_prepareBootloaderConfigFolder() 
        unless $self->{preparedBootloaderConfigFolder};

    my $prebootSystemInfo
        = clone($self->_pickSystemWithNewestKernel($systemInfos));

    $self->_createImages($client, $prebootSystemInfo);

    my $externalClientName   = externalConfigNameForClient($client);
    my $bootloaderPath       = "$self->{'target-path'}/bootloader";
    my $bootloaderConfigPath = "$bootloaderPath/$externalClientName";
    mkpath($bootloaderConfigPath)   unless $self->{'dry-run'};
    my $menuFile = "$bootloaderConfigPath/bootmenu.dialog";
    
    my $clientAppend = $client->{attrs}->{kernel_params_client} || '';
    vlog(1, _tr("writing bootmenu %s", $menuFile));

    # set label for each system
    foreach my $info (@$systemInfos) {
        my $label = $info->{label} || '';
        if (!length($label) || $label eq $info->{name}) {
            $label = $info->{name};
        }
        $info->{label} = $label;
    }
    my $bootmenuEntries = '';
    my $entryState = 'on';
    my $counter = 1;
    foreach my $info (sort { $a->{label} cmp $b->{label} } @$systemInfos) {
        my $vendorOSName = $info->{'vendor-os'}->{name};
        my $kernelName   = basename($info->{'kernel-file'});
        my $append       = $info->{attrs}->{kernel_params} || '';
        $append .= " $clientAppend";
        $bootmenuEntries .= qq{ "$counter" "$info->{label}" };
        $entryState = 'off';

        # create a file containing the boot-configuration for this system
        my $systemDescr = unshiftHereDoc(<<"        End-of-Here");
            label="$info->{label}"
            kernel="$vendorOSName/$kernelName"
            initramfs="$vendorOSName/$info->{'initramfs-name'}"
            append="$append"
        End-of-Here
        my $systemFile = "$bootloaderConfigPath/$info->{name}";
        spitFile(
            $systemFile, $systemDescr, { 'io-layer' => 'encoding(iso8859-1)' } 
        )    unless $self->{'dry-run'};
        slxsystem(qq{ln -sf $info->{name} $bootloaderConfigPath/$counter});
        $counter++;
    }

    my $entryCount = @$systemInfos;
    my $bootmenu = unshiftHereDoc(<<"    End-of-Here");
        --no-cancel --menu "OpenSLX Boot Menu" 20 65 $entryCount $bootmenuEntries
    End-of-Here
    
    if (!$self->{'dry-run'}) {
        # default to iso encoding, let's see how uclibc copes with it ...
        spitFile($menuFile, $bootmenu, { 'io-layer' => 'encoding(iso8859-1)' });

        # copy the preboot script into the folder to be tared
        my $prebootBasePath 
            = "$openslxConfig{'base-path'}/share/boot-env/preboot";
        slxsystem(qq{cp $prebootBasePath/preboot.sh $bootloaderConfigPath/});
        slxsystem(qq{cp -r $prebootBasePath/preboot-scripts $bootloaderConfigPath/});
        slxsystem(qq{chmod a+x $bootloaderConfigPath/preboot.sh});

        # create a tar which can/will be downloaded by prebooting clients
        my $tarCMD 
            = qq{cd $bootloaderConfigPath; tar -czf "${bootloaderConfigPath}.env" *};
        slxsystem($tarCMD);
        rmtree($bootloaderConfigPath);
    }

    return 1;
}

sub _createImages
{
    my $self   = shift;
    my $client = shift;
    my $info   = shift;

    my %mediaMap = (
        'cd'     => 'CD',
    );
    my $prebootMedia = $client->{attrs}->{preboot_media} || '';
    if (!$prebootMedia) {
        warn _tr(
            "no preboot-media defined for client %s, no images will be generated!",
            $client->{name}
        );
        return 0;
    }
    foreach my $mediumName (split m{, }, $prebootMedia) {
        my $moduleName = $mediaMap{$mediumName}
            or die _tr(
                "'%s' is not one of the supported preboot-medias (cd)", 
                $mediumName
            );

        my $prebootMedium = instantiateClass(
            "OpenSLX::BootEnvironment::Preboot::$moduleName"
        );
        $prebootMedium->initialize($self);
        $prebootMedium->createImage($client, $info);
    }
    
    return 1;
}

sub _prepareBootloaderConfigFolder
{
    my $self = shift;
    
    my $bootloaderPath = "$self->{'target-path'}/bootloader";
    if (!$self->{'dry-run'}) {
        rmtree($bootloaderPath);
        mkpath($bootloaderPath);
    }

    $self->{preparedBootloaderConfigFolder} = 1;

    return 1;
}

sub _pickSystemWithNewestKernel
{
    my $self        = shift;
    my $systemInfos = shift;

    my $systemWithNewestKernel;
    my $newestKernelFileSortKey = '';
    foreach my $system (@$systemInfos) {
        next unless $system->{'kernel-file'} =~ m{
            (?:vmlinuz|x86)-(\d+)\.(\d+)\.(\d+)(?:\.(\d+))?-(\d+(?:\.\d+)?)
        }x;
        my $sortKey 
            = sprintf("%02d.%02d.%02d.%02d-%2.1f", $1, $2, $3, $4||0, $5);
        if ($newestKernelFileSortKey lt $sortKey) {
            $systemWithNewestKernel  = $system;
            $newestKernelFileSortKey = $sortKey;
        }
    }

    if (!defined $systemWithNewestKernel) {
        die _tr("unable to pick a system to be used for preboot!");
    }
    return $systemWithNewestKernel;
}

1;