// Bits for XPathStepInfo options.
//
/// <summary>Append a path segment</summary>
/// <param name="segment">the segment to add</param>
public void Add(XmpPathSegment segment)
{
_segments.Add(segment);
}
// Bits for XPathStepInfo options.
//
/// <summary>Append a path segment</summary>
/// <param name="segment">the segment to add</param>
public void Add(XmpPathSegment segment)
{
_segments.Add(segment);
}
/// <summary>
/// After processing by ExpandXPath, a step can be of these forms:
/// </summary>
/// <remarks>
/// After processing by ExpandXPath, a step can be of these forms:
/// <list type="bullet">
/// <item>qualName - A top level property or struct field.</item>
/// <item>[index] - An element of an array.</item>
/// <item>[last()] - The last element of an array.</item>
/// <item>[qualName="value"] - An element in an array of structs, chosen by a field value.</item>
/// <item>[?qualName="value"] - An element in an array, chosen by a qualifier value.</item>
/// <item>?qualName - A general qualifier.</item>
/// </list>
/// Find the appropriate child node, resolving aliases, and optionally creating nodes.
/// </remarks>
/// <param name="parentNode">the node to start to start from</param>
/// <param name="nextStep">the xpath segment</param>
/// <param name="createNodes"></param>
/// <returns>returns the found or created XMPPath node</returns>
/// <exception cref="XmpException"></exception>
private static XmpNode FollowXPathStep(XmpNode parentNode, XmpPathSegment nextStep, bool createNodes)
{
XmpNode nextNode = null;
var stepKind = nextStep.Kind;
if (stepKind == XmpPath.StructFieldStep)
{
nextNode = FindChildNode(parentNode, nextStep.Name, createNodes);
}
else
{
if (stepKind == XmpPath.QualifierStep)
{
nextNode = FindQualifierNode(parentNode, nextStep.Name.Substring (1), createNodes);
}
else
{
// This is an array indexing step. First get the index, then get the node.
if (!parentNode.Options.IsArray)
{
throw new XmpException("Indexing applied to non-array", XmpErrorCode.BadXPath);
}
var index = 0;
if (stepKind == XmpPath.ArrayIndexStep)
{
index = FindIndexedItem(parentNode, nextStep.Name, createNodes);
}
else
{
if (stepKind == XmpPath.ArrayLastStep)
{
index = parentNode.GetChildrenLength();
}
else
{
if (stepKind == XmpPath.FieldSelectorStep)
{
var result = Utils.SplitNameAndValue(nextStep.Name);
var fieldName = result[0];
var fieldValue = result[1];
index = LookupFieldSelector(parentNode, fieldName, fieldValue);
}
else
{
if (stepKind == XmpPath.QualSelectorStep)
{
var result = Utils.SplitNameAndValue(nextStep.Name);
var qualName = result[0];
var qualValue = result[1];
index = LookupQualSelector(parentNode, qualName, qualValue, nextStep.AliasForm);
}
else
{
throw new XmpException("Unknown array indexing step in FollowXPathStep", XmpErrorCode.InternalFailure);
}
}
}
}
if (1 <= index && index <= parentNode.GetChildrenLength())
{
nextNode = parentNode.GetChild(index);
}
}
}
return nextNode;
}