/// <param name="destXmp">The destination XMP object.</param>
/// <param name="sourceNode">the source node</param>
/// <param name="destParent">the parent of the destination node</param>
/// <param name="replaceOldValues">Replace the values of existing properties.</param>
/// <param name="deleteEmptyValues">flag if properties with empty values should be deleted in the destination object.</param>
/// <exception cref="XmpException"/>
private static void AppendSubtree(XmpMeta destXmp, XmpNode sourceNode, XmpNode destParent, bool replaceOldValues, bool deleteEmptyValues)
{
var destNode = XmpNodeUtils.FindChildNode(destParent, sourceNode.Name, false);
var valueIsEmpty = false;
if (deleteEmptyValues)
{
valueIsEmpty = sourceNode.Options.IsSimple ? string.IsNullOrEmpty(sourceNode.Value) : !sourceNode.HasChildren;
}
if (deleteEmptyValues && valueIsEmpty)
{
if (destNode != null)
{
destParent.RemoveChild(destNode);
}
}
else
{
if (destNode == null)
{
// The one easy case, the destination does not exist.
destParent.AddChild((XmpNode)sourceNode.Clone());
}
else
{
if (replaceOldValues)
{
// The destination exists and should be replaced.
destXmp.SetNode(destNode, sourceNode.Value, sourceNode.Options, true);
destParent.RemoveChild(destNode);
destNode = (XmpNode)sourceNode.Clone();
destParent.AddChild(destNode);
}
else
{
// The destination exists and is not totally replaced. Structs and arrays are merged.
var sourceForm = sourceNode.Options;
var destForm = destNode.Options;
if (sourceForm != destForm)
{
return;
}
if (sourceForm.IsStruct)
{
// To merge a struct process the fields recursively. E.g. add simple missing fields.
// The recursive call to AppendSubtree will handle deletion for fields with empty
// values.
for (var it = sourceNode.IterateChildren(); it.HasNext();)
{
var sourceField = (XmpNode)it.Next();
AppendSubtree(destXmp, sourceField, destNode, replaceOldValues, deleteEmptyValues);
if (deleteEmptyValues && !destNode.HasChildren)
{
destParent.RemoveChild(destNode);
}
}
}
else if (sourceForm.IsArrayAltText)
{
// Merge AltText arrays by the "xml:lang" qualifiers. Make sure x-default is first.
// Make a special check for deletion of empty values. Meaningful in AltText arrays
// because the "xml:lang" qualifier provides unambiguous source/dest correspondence.
for (var it = sourceNode.IterateChildren(); it.HasNext();)
{
var sourceItem = (XmpNode)it.Next();
if (!sourceItem.HasQualifier || !XmpConstants.XmlLang.Equals(sourceItem.GetQualifier(1).Name))
{
continue;
}
var destIndex = XmpNodeUtils.LookupLanguageItem(destNode, sourceItem.GetQualifier(1).Value);
if (deleteEmptyValues && string.IsNullOrEmpty(sourceItem.Value))
{
if (destIndex != -1)
{
destNode.RemoveChild(destIndex);
if (!destNode.HasChildren)
{
destParent.RemoveChild(destNode);
}
}
}
else if (destIndex == -1)
{
// Not replacing, keep the existing item.
if (!XmpConstants.XDefault.Equals(sourceItem.GetQualifier(1).Value) || !destNode.HasChildren)
{
sourceItem.CloneSubtree(destNode);
}
else
{
var destItem = new XmpNode(sourceItem.Name, sourceItem.Value, sourceItem.Options);
sourceItem.CloneSubtree(destItem);
destNode.AddChild(1, destItem);
}
}
}
}
else if (sourceForm.IsArray)
{
// Merge other arrays by item values. Don't worry about order or duplicates. Source
// items with empty values do not cause deletion, that conflicts horribly with
// merging.
for (var children = sourceNode.IterateChildren(); children.HasNext();)
{
var sourceItem = (XmpNode)children.Next();
var match = false;
for (var id = destNode.IterateChildren(); id.HasNext();)
{
var destItem = (XmpNode)id.Next();
if (ItemValuesMatch(sourceItem, destItem))
{
match = true;
}
}
if (!match)
{
destNode = (XmpNode)sourceItem.Clone();
destParent.AddChild(destNode);
}
}
}
}
}
}
}
/// <summary>Performs a deep clone of the XMPMeta-object</summary>
public object Clone()
{
var clonedTree = (XmpNode)_tree.Clone();
return(new XmpMeta(clonedTree));
}