--- nfo/perl/libs/Data/Storage/Handler/Tangram.pm	2002/12/16 20:49:17	1.20
+++ nfo/perl/libs/Data/Storage/Handler/Tangram.pm	2003/05/10 17:31:18	1.36
@@ -1,8 +1,61 @@
 ############################################
 #
-#  $Id: Tangram.pm,v 1.20 2002/12/16 20:49:17 jonen Exp $
+#  $Id: Tangram.pm,v 1.36 2003/05/10 17:31:18 jonen Exp $
 #
 #  $Log: Tangram.pm,v $
+#  Revision 1.36  2003/05/10 17:31:18  jonen
+#  + added new functions related to 'create' item
+#   - createNode()
+#     # creates non-persistent 'deep dummy filled' object
+#   -
+#
+#  Revision 1.35  2003/04/19 16:09:48  jonen
+#  + added operator dispatching (currently for getting ref-type) at 'getListFiltered'
+#
+#  Revision 1.34  2003/04/11 01:18:53  joko
+#  sendQuery:
+#  + introduced crud action 'DELETE'
+#
+#  Revision 1.33  2003/04/09 06:07:43  joko
+#  revamped 'sub sendQuery'
+#
+#  Revision 1.32  2003/04/08 22:52:22  joko
+#  modified 'querySchema': better behaviour regarding filtering result
+#
+#  Revision 1.31  2003/04/05 21:24:09  joko
+#  modified 'sub getChildNodes': now contains code from 'querySchema'
+#
+#  Revision 1.30  2003/03/27 15:31:14  joko
+#  fixes to modules regarding new namespace(s) below Data::Mungle::*
+#
+#  Revision 1.29  2003/02/21 01:47:18  joko
+#  purged old code
+#  minor cosmetics
+#
+#  Revision 1.28  2003/02/20 20:20:26  joko
+#  tried to get auto-disconnect working again - failed with that
+#
+#  Revision 1.27  2003/01/31 06:30:59  joko
+#  + enabled 'sendQuery'
+#
+#  Revision 1.26  2003/01/30 22:29:47  joko
+#  + fixed module usage (removed dependency on 'libp.pm')
+#
+#  Revision 1.25  2003/01/19 02:30:05  joko
+#  + fix: modified call to '_initSchema'
+#
+#  Revision 1.24  2002/12/22 14:13:01  joko
+#  + sub dropDb
+#
+#  Revision 1.23  2002/12/19 16:31:53  joko
+#  +- renamed sub to 'rebuildDb'
+#
+#  Revision 1.22  2002/12/18 22:28:16  jonen
+#  + added extended logging at 'getObjectByGuid()'
+#
+#  Revision 1.21  2002/12/16 22:20:49  jonen
+#  + fixed bug at 'getObjectByGuid()'
+#
 #  Revision 1.20  2002/12/16 20:49:17  jonen
 #  + added sub 'getObjectByGuid()'
 #  + added functionality to use 'getObjectByGuid' at 'getObjectAsHash()'
@@ -20,7 +73,7 @@
 #  + fix: encapsulated object-loading inside an 'eval'
 #
 #  Revision 1.15  2002/12/05 13:55:21  joko
-#  + now utilizing 'object2hash' instead of 'var_deref'
+#  + now utilizing 'expand' instead of 'var_deref'
 #  + played around with having fresh-objects - no progress....
 #
 #  Revision 1.14  2002/12/05 09:40:30  jonen
@@ -93,14 +146,14 @@
 use base ("Data::Storage::Handler");
 use base ("Data::Storage::Handler::Abstract");
 
-use Tangram;
+
 use Data::Dumper;
-use libp qw( getNewPerlObjectByPkgName );
-use Data::Storage::Result::Tangram;
-use Data::Compare::Struct qw( isEmpty );
-use Data::Transform::Deep qw( object2hash );
-use Data::Transform::Encode qw( var2utf8 );
+use Tangram;
 
+use DesignPattern::Object;
+use Data::Storage::Result::Tangram;
+use Data::Mungle::Compare::Struct qw( isEmpty );
+use Data::Mungle::Transform::Deep qw( expand deep_copy merge_to );
 
 # get logger instance
 my $logger = Log::Dispatch::Config->instance;
@@ -121,7 +174,8 @@
   my $self = shift;
   $logger->debug( __PACKAGE__ . "->_initSchema()" );
   #if (!$schema_tangram) {
-    my $obj = getNewPerlObjectByPkgName($self->{locator}->{schema}, { EXPORT_OBJECTS => $self->{locator}->{classnames}, want_transactions => $self->{locator}->{want_transactions} } );
+    #my $obj = getNewPerlObjectByPkgName($self->{locator}->{schema}, { EXPORT_OBJECTS => $self->{locator}->{classnames}, want_transactions => $self->{locator}->{want_transactions} } );
+    my $obj = DesignPattern::Object->fromPackage($self->{locator}->{schema}, { 'EXPORT_OBJECTS' => $self->{locator}->{classnames}, 'want_transactions' => $self->{locator}->{want_transactions} } );
     $schema_tangram = $obj->getSchema();
   #}
   if (!$schema_tangram) {
@@ -154,8 +208,12 @@
     my $self = shift;
     
     my $dsn = shift;
+
+#print Dumper($self);
+#exit;
+
+    # TODO: re-enable
     $dsn ||= $self->{locator}->{dbi}->{dsn};
-    
     $logger->debug( __PACKAGE__ . "->connect( dsn $dsn )" );
     
     #my $storage = Tangram::Relational->connect( $schema, $dsn );
@@ -167,7 +225,8 @@
 #      return;
 #    }
 
-    return unless $self->_initSchema();
+    #return unless $self->_initSchema();
+    $self->_initSchema();
 
     # create the main tangram storage object
     #$self->{COREHANDLE} = Tangram::Relational->connect( $schema, $dsn );
@@ -194,33 +253,64 @@
 sub getChildNodes {
 
   my $self = shift;
-  my @nodes;
+  my $mode = shift;
+  my $filter = shift;
+  
+  $mode ||= 'core';
+  $filter ||= 'all';
+  
+  $logger->debug( __PACKAGE__ . "->getChildNodes($mode)" );
 
-  $logger->debug( __PACKAGE__ . "->getChildNodes()" );
+  if ($mode eq 'core') {
 
-  # create new DBI - Data::Storage - object from already connected DBI::db - handle inside the current COREHANDLE
-  #my $loc = new Data::Storage::Locator( type => "DBI", dbi => { db => $self->{COREHANDLE}->{db} });
-  #my $loc = new Data::Storage::Locator( type => "DBI", COREHANDLE => $self->{COREHANDLE}->{db} );
-  
-  # todo: should we retrieve information from the schema here
-  # rather than poorly getting table names from underlying dbi?
-  my $storage = $self->_getSubLayerHandle();
-  @nodes = @{$storage->getChildNodes()};
-  #$storage->_configureCOREHANDLE();
-#print "getchildnodes\n";
-#print Dumper($self);
-  #if (my $result = $self->sendCommand( 'SHOW TABLES;' ) ) {
+    my @nodes;
+    
+    # create new DBI - Data::Storage - object from already connected DBI::db - handle inside the current COREHANDLE
+    #my $loc = new Data::Storage::Locator( type => "DBI", dbi => { db => $self->{COREHANDLE}->{db} });
+    #my $loc = new Data::Storage::Locator( type => "DBI", COREHANDLE => $self->{COREHANDLE}->{db} );
+    
+    # todo: should we retrieve information from the schema here
+    # rather than poorly getting table names from underlying dbi?
+    my $storage = $self->_getSubLayerHandle();
+    @nodes = @{$storage->getChildNodes()};
+    #$storage->_configureCOREHANDLE();
+  #print "getchildnodes\n";
+  #print Dumper($self);
+    #if (my $result = $self->sendCommand( 'SHOW TABLES;' ) ) {
+    
+    # TODO: REVIEW
+    #$storage->disconnect();
+    
+    $self->{meta}->{childnodes} = \@nodes;
+
+    return \@nodes;
   
-  # TODO: REVIEW
-  #$storage->disconnect();
+  } elsif ($mode eq 'root') {
+    
+    # FIXME: this will return *all* known classes to 'Class::Tangram',
+    # which might not be what you expect since more than one instance
+    # of Tangram may be in memory and Class::Tangram seems to 
+    # offer no methods to determine this or filter its result(s) according
+    # to a specific database.
+    my @object_names = Class::Tangram::known_classes();
+    my @concret_names;
+    my $o_cnt;
+    foreach (sort @object_names) {
+      push @concret_names, $_  if (!Class::Tangram::class_is_abstract($_));
+      $o_cnt++;
+    }
+
+    if ($filter eq 'all') {
+      return \@object_names;
+    } elsif ($filter eq 'concrete') {
+      return \@concret_names;
+    }
   
-  $self->{meta}->{childnodes} = \@nodes;
+  }
   
-  return \@nodes;
 
 }
 
-
 sub testIntegrity {
 
   my $self = shift;
@@ -294,6 +384,8 @@
   $logger->debug( __PACKAGE__ . "->configureCOREHANDLE" );
 
   #my $subLayer = $self->_getSubLayerHandle();
+  #print Dumper($self);
+  #exit;
 
   # apply configured modifications
     if (exists $self->{dbi}->{trace_level} && exists $self->{dbi}->{trace_file}) {
@@ -359,9 +451,9 @@
   return $ok;
 }
 
-sub rebuildDbAndSchema {
+sub rebuildDb {
   my $self = shift;
-  $logger->info( __PACKAGE__ . "->rebuildDbAndSchema()" );
+  $logger->info( __PACKAGE__ . "->rebuildDb()" );
   my @results;
 
   # sum up results (bool (0/1)) in array
@@ -401,7 +493,7 @@
   my @results;
   $logger->debug( __PACKAGE__ . "->getListFiltered( nodename => '" . $nodename . "' )" );
 
-  #print Dumper($filters);
+#print Dumper($filters);
   
   my @tfilters;
   
@@ -423,8 +515,14 @@
   #    objects => $objects,
   #  );
   
-    # HACK: build eval-string (sorry) to get filtered list - please give advice here
-    push @tfilters, '$remote->{' . $filter->{key} . '}' . " $filter->{op} '$filter->{val}'";
+    # TODO: is_op?
+    # dispatch un-common operators if exists
+    if($filter->{op} eq "ref") {
+      push @tfilters, 'ref($remote->{' . $filter->{key} . '})' . " eq '$filter->{val}'";
+    } else {
+      # HACK: build eval-string (sorry) to get filtered list - please give advice here
+      push @tfilters, '$remote->{' . $filter->{key} . '}' . " $filter->{op} '$filter->{val}'";
+    }
 
   }
 
@@ -440,6 +538,8 @@
   # HACK: build eval-string (sorry) to get filtered list - please give advice here
   my $evalstring = 'return $self->{_COREHANDLE}->select($remote, ' . $tfilter . ');';
   
+  #print "eval: $evalstring", "\n";
+  
   # get filtered list/set
   @results = eval($evalstring);
   die $@ if $@;
@@ -475,49 +575,167 @@
 sub sendQuery {
   my $self = shift;
   my $query = shift;
-  #my $sql = "SELECT cs FROM $self->{metainfo}->{$descent}->{node} WHERE $self->{metainfo}->{$descent}->{IdentProvider}->{arg}='$self->{entry}->{source}->{ident}';";
-  #my $result = $self->{metainfo}->{$descent}->{storage}->sendCommand($sql);
 
   #print Dumper($query);
 
-  # HACK: special case: querying by id does not translate into a common tangram query
-  # just load the object by given id(ent)
-  if ($query->{criterias}->[0]->{key} eq 'id' && $query->{criterias}->[0]->{op} eq 'eq') {
-    #print "LOAD!!!", "\n";
-    #exit;
-    #return Set::Object->new( $self->{COREHANDLE}->load($query->{criterias}->[0]->{val}) );
-    my $ident = $query->{criterias}->[0]->{val};
-#print "load obj", "\n";
-    #return $self->createSet() if $ident == 5;
-    $self->{_COREHANDLE}->unload($ident);
-    my $object = $self->{_COREHANDLE}->load($ident);
-#print "get id", "\n";
-    my $oid = $self->{_COREHANDLE}->id($object);
-#print Dumper($object);
-#print "oid: $oid", "\n";
-    return $self->createSet($object);
-    #return $self->createSet( $self->{COREHANDLE}->load('300090018') );
-  }
-
-  die("This should not be reached for now - redirect to \$self->getListFiltered() here!");
-
-  # TODO: do a common tangram query here
-
-  my @crits;
-  foreach (@{$query->{criterias}}) {
-    my $op = '';
-    $op = '=' if lc $_->{op} eq 'eq';
-    push @crits, "$_->{key}$op'$_->{val}'";
-  }
-  my $subnodes = {};
-  map { $subnodes->{$_}++ } @{$query->{subnodes}};
-  # HACK: this is hardcoded ;(    expand possibilities!
-  #my $crit = join(' AND ', @crits);
-  #my $sql = hash2Sql($query->{node}, $subnodes, 'SELECT', $crit);
-  #return $self->sendCommand($sql);
-  #my $h = $self->{COREHANDLE}->remote($query->{node});
-  #my $res = $self->{COREHANDLE}->select($h, $h->{);
-  return $self->createCursor($query->{node});
+  # type = ITEM|LIST|TRANSPARENT
+  my $type = '';
+  # mode = OID|SPECIAL
+  my $mode = '';
+  my $ident = '';
+  my $crud = '';
+  
+  
+  # dispatch type and mode
+  
+    # defaults - 1
+    if ($query->{options}) {
+      $crud = $query->{options}->{crud};
+      $crud ||= $query->{options}->{action};
+    }
+
+    # defaults - 2
+    $type ||= 'TRANSPARENT'; 
+    $crud ||= 'RETRIEVE';
+
+    if ($query->{options}->{OID}) {
+      $type = 'ITEM';
+      $mode = 'OID';
+      $ident = $query->{options}->{OID};
+    
+    } elsif (my $guid = $query->{options}->{GUID}) {
+      $type = 'TRANSPARENT';
+      $query->{criterias} = [ { key => 'guid', op => 'eq', val => $guid } ];    
+
+    # if operator is different (dispatcher for 'getListFiltered')
+    } elsif (my $op = $query->{options}->{op}) {
+      $type = 'TRANSPARENT';
+      $query->{criterias} = [ { key => $query->{options}->{meta_label}, op => $op, val => $query->{options}->{meta_value} } ];    
+
+    }
+  
+    # HACK: special case: querying by id does not translate into a common tangram query
+    # just load the object by given identifier (OID) named 'id' - this is required by Data::Transfer::Sync!
+    if ($query->{criterias} && ($query->{criterias}->[0]->{key} eq 'id' && $query->{criterias}->[0]->{op} eq 'eq')) {
+      $type = 'ITEM';
+      $mode = 'SPECIAL.SYNC';
+      $ident = $query->{criterias}->[0]->{val};
+    }
+  
+
+  # execute query
+  my $result;
+
+  if ($type eq 'ITEM' && $ident) {
+
+    if ($mode eq 'OID') {    
+      # TODO: review this case!
+      $result = $self->getObject($ident, $query->{options});
+    
+    } elsif ($mode eq 'SPECIAL.SYNC') {
+
+      # V1 - failed
+      #return Set::Object->new( $self->{COREHANDLE}->load($query->{criterias}->[0]->{val}) );
+  
+      # hmm....
+      #return $self->createSet() if $ident == 5;
+      
+      # Unload single object before doing any further operations to 
+      # expect a "fresh" object from orm when performing the next calls.
+      $self->{_COREHANDLE}->unload($ident);
+      
+      # Load object from orm.
+      my $object = $self->{_COREHANDLE}->load($ident);
+  
+      # determine object identifier (OID)
+      my $oid = $self->{_COREHANDLE}->id($object);
+      
+      # encapsulate into result/response container and return this one
+      $result = $self->createSet($object);
+      
+      # debugging
+      #$result = $self->createSet( $self->{COREHANDLE}->load('300090018') );
+
+    }
+    
+  
+  } elsif ($type eq 'TRANSPARENT') {
+
+    if ($crud eq 'RETRIEVE') {
+
+      my $list = $self->getListFiltered($query->{node}, $query->{criterias});
+      #return $self->createSet($object);
+      #return $self->createSet($list);
+      return $self->createSet(@$list);
+    
+      #die("This should not be reached for now - redirect to \$self->getListFiltered() here!");
+    
+      # try a generic tangram query here
+      # TODO: try to place an oql on top of that (search.cpan.org!)
+      my @crits;
+      foreach (@{$query->{criterias}}) {
+        my $op = '';
+        $op = '=' if lc $_->{op} eq 'eq';
+        push @crits, "$_->{key}$op'$_->{val}'";
+      }
+      my $subnodes = {};
+      map { $subnodes->{$_}++ } @{$query->{subnodes}};
+      # HACK: this is hardcoded ;(    expand possibilities!
+      #my $crit = join(' AND ', @crits);
+      #my $sql = hash2Sql($query->{node}, $subnodes, 'SELECT', $crit);
+      #return $self->sendCommand($sql);
+      #my $h = $self->{COREHANDLE}->remote($query->{node});
+      #my $res = $self->{COREHANDLE}->select($h, $h->{);
+      $result = $self->createCursor($query->{node});
+
+    } elsif ($crud eq 'UPDATE') {
+
+      # Patch current query to be a loader (e.g. change action, remove payload) ...
+      my $childquery = deep_copy($query);
+      $childquery->{options}->{crud} = 'RETRIEVE';
+      delete $childquery->{payload};
+
+      # ... to use it to fetch a fresh object using ourselves (sendQuery).
+      my $cursor = $self->sendQuery($childquery);
+      my $status = $cursor->getStatus();
+      my $object = $cursor->getNextEntry();
+
+      # Merge values and apply value modifiers.
+      my $options = { utf8 => 1, php => 1 };
+      merge_to($object, $query->{payload}, $options);
+
+      # Execute update operation at orm.
+      $self->update($object);
+    
+    } elsif ($crud eq 'DELETE') {
+
+      # Patch current query to be a loader (e.g. change action) ...
+      my $childquery = deep_copy($query);
+      $childquery->{options}->{crud} = 'RETRIEVE';
+
+      # ... to use it to fetch a fresh object using ourselves (sendQuery).
+      my $cursor = $self->sendQuery($childquery);
+      my $status = $cursor->getStatus();
+      my $object = $cursor->getNextEntry();
+
+      $self->erase($object);
+
+    } elsif ($crud eq 'CREATE') {
+      
+      my $nodename = $query->{node};      
+      my $newnode = $self->createNode($nodename);
+      my $id = $self->{_COREHANDLE}->insert($newnode);
+  
+      print "Saved new node $nodename with GUID $newnode->{guid}, OID '$id': " . Dumper($newnode) . "\n";
+      
+      return $newnode;
+
+    }
+
+  }
+
+  return $result;
+
 }
 
 sub eraseAll {
@@ -553,13 +771,14 @@
   return $object if $object;
 }
 
-sub getObjectByGuid {
+sub getObjectByGuid_old {
   my $self = shift;
   my $guid = shift;
   my $options = shift;
   
   # Guid and Classname is needed
   if(!$guid || !$options->{classname}) {
+   $logger->error( __PACKAGE__ . "->getObjectByGuid: No 'guid' OR no Classname in options hash was given but needed!" );
     return;
   }
   
@@ -568,20 +787,21 @@
   $self->{_COREHANDLE}->unload() if ($options->{destroy});
 
   # search for object with given Classname and Guid
-  my $obj_tmp = $self->{_COREHANDLE}->remote($classname);
+  my $obj_tmp = $self->{_COREHANDLE}->remote($options->{classname});
   my @result = $self->{_COREHANDLE}->select($obj_tmp, $obj_tmp->{guid} eq $guid);
   
   # we searched for global unique identifer of some object,
-  # so it think we can trust there would be only one result
+  # so I think we can trust there would be only one result
   if($result[0]) {
     return $result[0];
   } else {
-    return "No Object with Classname $classname and GUID $options->{guid} found!";
+    $logger->error( __PACKAGE__ . "->getObjectByGuid: No Object with Classname $options->{classname} and GUID $guid found!" );
+    return;
   }
   
 }
 
-sub getObjectAsHash {
+sub getObjectAsHash_old {
   my $self = shift;
   my $oid = shift;
   my $options = shift;  
@@ -596,27 +816,29 @@
   # build options (a callback to unload autovivified objects) for 'expand'
   # TODO: use $logger to write to debug here!
   my $cb; # = sub {};
+
+  # deactivated way to get rid of used instances, if requested
 =pod
-  if ($options->{destroy}) {
-    $options->{cb}->{destroy} = sub {
-      print "================ DESTROY", "\n";
-      my $object = shift;
-      #print Dumper($object);
-      $self->{_COREHANDLE}->unload($object);
-      #undef($object);
-    };
-  }
+    if ($options->{destroy}) {
+      $options->{cb}->{destroy} = sub {
+        print "================ DESTROY", "\n";
+        my $object = shift;
+        #print Dumper($object);
+        $self->{_COREHANDLE}->unload($object);
+        #undef($object);
+      };
+    }
 =cut
 
-  my $hash = object2hash($obj, $options);
-  #$options->{cb}->{destroy}->($obj);
-  #$self->{_COREHANDLE}->unload($obj);
-  
-  # convert values in hash to utf8 to be ready for (e.g.) encapsulation in XML
-  # now done in object2hash
-  #var2utf8($hash) if ($options->{utf8});
+  my $hash = expand($obj, $options);
+
+  # old (unsuccessful) attempts to get rid of used instances, if requested
+
+    # V1:
+    #$options->{cb}->{destroy}->($obj);
+    #$self->{_COREHANDLE}->unload($obj);
   
-  # old (wrong) attempts to get rid of used instances, if requested
+    # V2:
     #$obj->clear_refs;
     #$self->{COREHANDLE}->unload($obj) if($options->{destroy});
     #$obj->DESTROY;
@@ -634,4 +856,150 @@
   return $self->{_COREHANDLE};
 }
 
+sub dropDb {
+  my $self = shift;
+  my $storage = $self->_getSubLayerHandle();
+  return $storage->dropDb();
+}
+
+sub testAvailability {
+  my $self = shift;
+  my $storage = $self->_getSubLayerHandle();
+  return $storage->testAvailability();
+}
+
+sub disconnect2 {
+  my $self = shift;
+  my $storage = $self->_getSubLayerHandle();
+  print "DISC!", "\n";
+
+  my $storage_ll = $storage->{_COREHANDLE};
+  $storage_ll->disconnect();
+  
+  print Dumper($storage);
+  exit;
+  
+  #$self->{_COREHANDLE}
+  #$storage->disconnect();
+  $self->{dataStorageLayer}->disconnect();
+}
+
+
+sub createNode {
+  my $self = shift;
+  my $classname = shift;
+
+  my $obj = $classname->new();
+  
+  my $attr_options = Class::Tangram::attribute_options($classname);
+  #print "Attribute Options: " . Dumper($attr_options);
+
+  my $attr_types = Class::Tangram::attribute_types($classname);
+  #print "Attribute Types: " . Dumper($attr_types);
+  
+  foreach(keys %{$attr_types}) {
+    if($attr_types->{$_} eq 'string') {
+      $obj->{$_} = '';
+    } elsif($attr_types->{$_} eq 'int') {
+      $obj->{$_} = 0;
+    } elsif($attr_types->{$_} eq 'real') {
+      $obj->{$_} = 0;
+    } elsif($attr_types->{$_} eq 'rawdatetime') {
+      $obj->{$_} = '0000-00-00 00:00:00';
+    } elsif($attr_types->{$_} eq 'ref') {
+      if($attr_options->{$_}->{class}) {
+        $obj->{$_} = $self->createNode($attr_options->{$_}->{class});
+      } else {
+        #$obj->{$_} = undef();
+      }
+    } elsif($attr_types->{$_} eq 'iarray') {
+        $obj->{$_} = [ ];
+    } elsif($attr_types->{$_} eq 'hash') {
+        $obj->{$_} = {  };
+    } elsif($attr_types->{$_} eq 'flat_hash') {
+        $obj->{$_} = { };
+    }
+  }
+  
+  #print "New Object: " . Dumper($obj);
+  
+  return $obj;
+}
+
+
+  sub insertChildNode {
+    my $self = shift;
+    my $child_entry = shift;
+    my $query_args = shift;
+    
+    my $core = $self->{_COREHANDLE};
+    my $nodename = $query_args->{nodename};
+    
+    # get parent object
+    my $query = {
+          node => $query_args->{parent}->{nodename},
+          options => { GUID => $query_args->{parent}->{guid}, },
+          };
+    my $cursor = $self->sendQuery($query);
+    my $parent = $cursor->getNextEntry();
+
+    # debug
+    #print "Parent_org: " . Dumper($parent);
+        
+    # Create child node object if isn't already done 
+    # ($child_entry have to be the class name then...)
+    if(!ref($child_entry)) {
+      $child_entry = $self->createNode($child_entry);
+      # it could be insert 'manually' or will be insert 'transparent' if parent will be updated
+      #$core->insert($child_entry);
+      #print "Create child object [$nodename]: " . Dumper($child_entry);
+    }
+
+    # get reference of tied node
+    my $tied_node = tied $parent->{$nodename};
+
+    # insert/change child entry at parent
+    #print "reference: " . ref($parent->{$nodename}) . "\n";
+    if(ref($parent->{$nodename}) eq 'ARRAY') {
+      # all tangram types are tied as 'SCALAR' with special 'FETCH', 'STORE' methods per type,
+      # so a 'PUSH' is not implemented (which could be then done transparently)
+      my $array = $tied_node->FETCH;
+      push @$array, $child_entry;
+      $tied_node->STORE($array);
+      # node will be normaly untied at 'STORE'
+      if(tied $parent->{$nodename}) { print "already tied !!\n"; }
+      else { undef $tied_node; }
+    }
+    elsif(ref($parent->{$nodename}) eq 'HASH') {
+      if(my $key = $query_args->{hash_key}) {
+        # same problem as with 'ARRAY':
+        # all tangram types are tied as 'SCALAR' with special 'FETCH', 'STORE' methods per type.
+        my $hash = $tied_node->FETCH;
+        $hash->{$key} = $child_entry;
+        $tied_node->STORE($hash); 
+        # node will be normaly untied at 'STORE'
+        if(tied $parent->{$nodename}) { print "already tied !!\n"; }
+        else { undef $tied_node; }
+      } else {
+       print "ERROR: No HASH KEY given, so not able to insert hash entry!";
+      }
+    } 
+    else {
+      $parent->{$nodename} = $child_entry;
+    }
+
+    # debug
+    #print "Parent_new: " . Dumper($parent);
+    
+    # save parent
+    $core->update($parent);
+    
+    # debug
+    #print "Saved Parent: ". Dumper($parent);
+    
+    return $child_entry;
+  }
+
+
 1;
+__END__