#!/usr/bin/perl

use strict;
use warnings;

use Sort::Tree;
use YAML::XS;
use Data::Dumper;

## load structure
my $yaml = YAML::XS::Load( yaml() );

## convert structure to array
my @list;
foreach my $key (reverse sort keys %$yaml){
    my $item = $$yaml{$key};
    push(@list, $item);
}

## compare the output of these:
my @tree = list_to_tree(\@list, 'id', 'parent');
# my @tree = list_to_multileveltree(\@list, 'id', 'parent');

print Dumper(\@tree);


sub list_to_multileveltree {
        my ($arrayref,$id,$parent) = @_;

        my @tree = list_to_tree($arrayref, $id, $parent);
#       while(has_kids(\@list)){
                for my $index (0 .. $#tree){
                        my $task = $tree[$index];
                        if($task->{$parent}){
                                Sort::Tree::traverse(\@tree,
                                        method          => \&appendKid
+s,
                                        removeId        => $task->{$id
+},
                                        removeIndex     => $index,
                                        parentId        => $task->{$pa
+rent},
                                        treeref         => \@tree,
                                );
                        }
                }
#       }

        return @tree;
}
sub appendKids {
        my %details = @_;

        if($details{item}->{id} == $details{parentId}){
                $details{item}->{appendKids} = 'was here' . " ## $deta
+ils{removeId} $details{removeIndex} $details{parentId}";
                push(
                        @{ $details{item}->{kids} },
                        ${ $details{treeref} }[$details{removeIndex}]
                );
                splice(@{ $details{treeref} }, $details{removeIndex}, 
+1);
        }

        return 0; # continue processing tree
}
# check if the tree has kids left on top level (unused)
sub has_kids {
        my $ref = shift;

        my $has_kids;
        foreach my $key (keys %$ref){
                my $task = $$ref{$key};

                if($task->{parent}){
                        $has_kids = 1;
                }
        }

        return $has_kids;
}


sub yaml {
return "
---
'1317074400':
  id: 1317074400
'1320678979':
  id: 1320678979
  body: Nest Top
'1320678979.5':
  id: 1320678979.5
  parent: 1320678979
  body: Nest 1
'1320678979.01':
  id: 1320678979.01
  parent: 1320678979
  body: Nest 1.1
'1320678979.1':
  id: 1320678979.1
  body: Nest 2
'1320678979.2':
  id: 1320678979.2
  parent: 1320678979.1
  body: Nest G
'1320678979.3':
  id: 1320678979.3
  parent: 1320678979.2
  body: Nest 3.1
'1320678979.4':
  id: 1320678979.4
  parent: 1320678979.2
  body: Nest 3.2
'1320678981':
  id: 1320678981
  body: Nest 0
'1320678982':
  id: 1320678982
  body: Nest 1
  parent: 1320678981
'1320678983':
  id: 1320678983
  parent: 1320678982
  body: Nest 2
'1320678984':
  id: 1320678984
  parent: 1320678983
  body: Nest 4
'1320678985':
  id: 1320678985
  parent: 1320678984
  body: Nest 5
";
}
[download]