#!/usr/bin/perl -w

use Linux::LVM;
use JSON;

my $what = $ARGV[0];

open STDERR, '>/dev/null';

my $json;
@{$json->{data}} = ();

if ($what eq "volumes"){
    foreach my $group (get_volume_group_list()){
        my %lvs = get_logical_volume_information($group);
        foreach my $lv (keys %lvs){
            $lv = ($lv =~ m!^/dev/$group!) ? $lv : "/dev/$group/$lv";
            push @{$json->{data}}, { "{#LVMVOL}" => "$lv" };
        }
    }
}
elsif ($what eq "snapshots"){
    foreach my $group (get_volume_group_list()){
        my %lvs = get_logical_volume_information($group);
        foreach my $lv (keys %lvs){
            if (defined $lvs{$lv}->{allocated_to_snapshot}){
                $lv = ($lv =~ m!^/dev/$group!) ? $lv : "/dev/$group/$lv";
                push @{$json->{data}}, { "{#LVMSNAP}" => "$lv" };
            }
        }
    }
}
elsif ($what eq "thin_pools"){
    foreach my $group (get_volume_group_list()){
        my %lvs = get_logical_volume_information($group);
        foreach my $lv (keys %lvs){
            if (defined $lvs{$lv}->{allocated_pool_data}){
                $lv = ($lv =~ m!^/dev/$group!) ? $lv : "/dev/$group/$lv";
                push @{$json->{data}}, { "{#LVMTHINP}" => "$lv" };
            }
        }
    }
}
elsif ($what eq "groups"){
    foreach my $group (get_volume_group_list()){
        push @{$json->{data}}, { "{#LVMGRP}" => $group };
    }
}
else{
    print <<"EOF";

Usage: $0 [volumes|snapshots|groups]

EOF
}

print to_json($json);
exit(0);