/// <summary>
/// Parses the root node of an XMP Path, checks if namespace and prefix fit together
/// and resolve the property to the base property if it is an alias.
/// </summary>
/// <param name="schemaNS">the root namespace</param>
/// <param name="pos">the parsing position helper</param>
/// <param name="expandedXPath">the path to contribute to</param>
/// <exception cref="Com.Adobe.Xmp.XMPException">If the path is not valid.</exception>
private static void ParseRootNode(string schemaNS, PathPosition pos, XMPPath expandedXPath)
{
while (pos.stepEnd < pos.path.Length && "/[*".IndexOf(pos.path[pos.stepEnd]) < 0)
{
pos.stepEnd++;
}
if (pos.stepEnd == pos.stepBegin)
{
throw new XMPException("Empty initial XMPPath step", XMPErrorConstants.Badxpath);
}
string rootProp = VerifyXPathRoot(schemaNS, Sharpen.Runtime.Substring(pos.path, pos.stepBegin, pos.stepEnd));
XMPAliasInfo aliasInfo = XMPMetaFactory.GetSchemaRegistry().FindAlias(rootProp);
if (aliasInfo == null)
{
// add schema xpath step
expandedXPath.Add(new XMPPathSegment(schemaNS, XMPPath.SchemaNode));
XMPPathSegment rootStep = new XMPPathSegment(rootProp, XMPPath.StructFieldStep);
expandedXPath.Add(rootStep);
}
else
{
// add schema xpath step and base step of alias
expandedXPath.Add(new XMPPathSegment(aliasInfo.GetNamespace(), XMPPath.SchemaNode));
XMPPathSegment rootStep = new XMPPathSegment(VerifyXPathRoot(aliasInfo.GetNamespace(), aliasInfo.GetPropName()), XMPPath.StructFieldStep);
rootStep.SetAlias(true);
rootStep.SetAliasForm(aliasInfo.GetAliasForm().GetOptions());
expandedXPath.Add(rootStep);
if (aliasInfo.GetAliasForm().IsArrayAltText())
{
XMPPathSegment qualSelectorStep = new XMPPathSegment("[?xml:lang='x-default']", XMPPath.QualSelectorStep);
qualSelectorStep.SetAlias(true);
qualSelectorStep.SetAliasForm(aliasInfo.GetAliasForm().GetOptions());
expandedXPath.Add(qualSelectorStep);
}
else
{
if (aliasInfo.GetAliasForm().IsArray())
{
XMPPathSegment indexStep = new XMPPathSegment("[1]", XMPPath.ArrayIndexStep);
indexStep.SetAlias(true);
indexStep.SetAliasForm(aliasInfo.GetAliasForm().GetOptions());
expandedXPath.Add(indexStep);
}
}
}
}
// empty
/// <summary>
/// Split an XMPPath expression apart at the conceptual steps, adding the
/// root namespace prefix to the first property component.
/// </summary>
/// <remarks>
/// Split an XMPPath expression apart at the conceptual steps, adding the
/// root namespace prefix to the first property component. The schema URI is
/// put in the first (0th) slot in the expanded XMPPath. Check if the top
/// level component is an alias, but don't resolve it.
/// <p>
/// In the most verbose case steps are separated by '/', and each step can be
/// of these forms:
/// <dl>
/// <dt>prefix:name
/// <dd> A top level property or struct field.
/// <dt>[index]
/// <dd> An element of an array.
/// <dt>[last()]
/// <dd> The last element of an array.
/// <dt>[fieldName="value"]
/// <dd> An element in an array of structs, chosen by a field value.
/// <dt>[@xml:lang="value"]
/// <dd> An element in an alt-text array, chosen by the xml:lang qualifier.
/// <dt>[?qualName="value"]
/// <dd> An element in an array, chosen by a qualifier value.
/// <dt>@xml:lang
/// <dd> An xml:lang qualifier.
/// <dt>?qualName
/// <dd> A general qualifier.
/// </dl>
/// <p>
/// The logic is complicated though by shorthand for arrays, the separating
/// '/' and leading '*' are optional. These are all equivalent: array/*[2]
/// array/[2] array*[2] array[2] All of these are broken into the 2 steps
/// "array" and "[2]".
/// <p>
/// The value portion in the array selector forms is a string quoted by '''
/// or '"'. The value may contain any character including a doubled quoting
/// character. The value may be empty.
/// <p>
/// The syntax isn't checked, but an XML name begins with a letter or '_',
/// and contains letters, digits, '.', '-', '_', and a bunch of special
/// non-ASCII Unicode characters. An XML qualified name is a pair of names
/// separated by a colon.
/// </remarks>
/// <param name="schemaNS">schema namespace</param>
/// <param name="path">property name</param>
/// <returns>Returns the expandet XMPPath.</returns>
/// <exception cref="Com.Adobe.Xmp.XMPException">Thrown if the format is not correct somehow.</exception>
public static XMPPath ExpandXPath(string schemaNS, string path)
{
if (schemaNS == null || path == null)
{
throw new XMPException("Parameter must not be null", XMPErrorConstants.Badparam);
}
XMPPath expandedXPath = new XMPPath();
PathPosition pos = new PathPosition();
pos.path = path;
// Pull out the first component and do some special processing on it: add the schema
// namespace prefix and and see if it is an alias. The start must be a "qualName".
ParseRootNode(schemaNS, pos, expandedXPath);
// Now continue to process the rest of the XMPPath string.
while (pos.stepEnd < path.Length)
{
pos.stepBegin = pos.stepEnd;
SkipPathDelimiter(path, pos);
pos.stepEnd = pos.stepBegin;
XMPPathSegment segment;
if (path[pos.stepBegin] != '[')
{
// A struct field or qualifier.
segment = ParseStructSegment(pos);
}
else
{
// One of the array forms.
segment = ParseIndexSegment(pos);
}
if (segment.GetKind() == XMPPath.StructFieldStep)
{
if (segment.GetName()[0] == '@')
{
segment.SetName("?" + Sharpen.Runtime.Substring(segment.GetName(), 1));
if (!"?xml:lang".Equals(segment.GetName()))
{
throw new XMPException("Only xml:lang allowed with '@'", XMPErrorConstants.Badxpath);
}
}
if (segment.GetName()[0] == '?')
{
pos.nameStart++;
segment.SetKind(XMPPath.QualifierStep);
}
VerifyQualName(Sharpen.Runtime.Substring(pos.path, pos.nameStart, pos.nameEnd));
}
else
{
if (segment.GetKind() == XMPPath.FieldSelectorStep)
{
if (segment.GetName()[1] == '@')
{
segment.SetName("[?" + Sharpen.Runtime.Substring(segment.GetName(), 2));
if (!segment.GetName().StartsWith("[?xml:lang="))
{
throw new XMPException("Only xml:lang allowed with '@'", XMPErrorConstants.Badxpath);
}
}
if (segment.GetName()[1] == '?')
{
pos.nameStart++;
segment.SetKind(XMPPath.QualSelectorStep);
VerifyQualName(Sharpen.Runtime.Substring(pos.path, pos.nameStart, pos.nameEnd));
}
}
}
expandedXPath.Add(segment);
}
return(expandedXPath);
}
// empty
/// <summary>
/// Split an XMPPath expression apart at the conceptual steps, adding the
/// root namespace prefix to the first property component.
/// </summary>
/// <remarks>
/// Split an XMPPath expression apart at the conceptual steps, adding the
/// root namespace prefix to the first property component. The schema URI is
/// put in the first (0th) slot in the expanded XMPPath. Check if the top
/// level component is an alias, but don't resolve it.
/// <p>
/// In the most verbose case steps are separated by '/', and each step can be
/// of these forms:
/// <dl>
/// <dt>prefix:name
/// <dd> A top level property or struct field.
/// <dt>[index]
/// <dd> An element of an array.
/// <dt>[last()]
/// <dd> The last element of an array.
/// <dt>[fieldName="value"]
/// <dd> An element in an array of structs, chosen by a field value.
/// <dt>[@xml:lang="value"]
/// <dd> An element in an alt-text array, chosen by the xml:lang qualifier.
/// <dt>[?qualName="value"]
/// <dd> An element in an array, chosen by a qualifier value.
/// <dt>@xml:lang
/// <dd> An xml:lang qualifier.
/// <dt>?qualName
/// <dd> A general qualifier.
/// </dl>
/// <p>
/// The logic is complicated though by shorthand for arrays, the separating
/// '/' and leading '*' are optional. These are all equivalent: array/*[2]
/// array/[2] array*[2] array[2] All of these are broken into the 2 steps
/// "array" and "[2]".
/// <p>
/// The value portion in the array selector forms is a string quoted by '''
/// or '"'. The value may contain any character including a doubled quoting
/// character. The value may be empty.
/// <p>
/// The syntax isn't checked, but an XML name begins with a letter or '_',
/// and contains letters, digits, '.', '-', '_', and a bunch of special
/// non-ASCII Unicode characters. An XML qualified name is a pair of names
/// separated by a colon.
/// </remarks>
/// <param name="schemaNS">schema namespace</param>
/// <param name="path">property name</param>
/// <returns>Returns the expandet XMPPath.</returns>
/// <exception cref="Com.Adobe.Xmp.XMPException">Thrown if the format is not correct somehow.</exception>
public static XMPPath ExpandXPath(string schemaNS, string path)
{
if (schemaNS == null || path == null)
{
throw new XMPException("Parameter must not be null", XMPErrorConstants.Badparam);
}
XMPPath expandedXPath = new XMPPath();
PathPosition pos = new PathPosition();
pos.path = path;
// Pull out the first component and do some special processing on it: add the schema
// namespace prefix and and see if it is an alias. The start must be a "qualName".
ParseRootNode(schemaNS, pos, expandedXPath);
// Now continue to process the rest of the XMPPath string.
while (pos.stepEnd < path.Length)
{
pos.stepBegin = pos.stepEnd;
SkipPathDelimiter(path, pos);
pos.stepEnd = pos.stepBegin;
XMPPathSegment segment;
if (path[pos.stepBegin] != '[')
{
// A struct field or qualifier.
segment = ParseStructSegment(pos);
}
else
{
// One of the array forms.
segment = ParseIndexSegment(pos);
}
if (segment.GetKind() == XMPPath.StructFieldStep)
{
if (segment.GetName()[0] == '@')
{
segment.SetName("?" + Sharpen.Runtime.Substring(segment.GetName(), 1));
if (!"?xml:lang".Equals(segment.GetName()))
{
throw new XMPException("Only xml:lang allowed with '@'", XMPErrorConstants.Badxpath);
}
}
if (segment.GetName()[0] == '?')
{
pos.nameStart++;
segment.SetKind(XMPPath.QualifierStep);
}
VerifyQualName(Sharpen.Runtime.Substring(pos.path, pos.nameStart, pos.nameEnd));
}
else
{
if (segment.GetKind() == XMPPath.FieldSelectorStep)
{
if (segment.GetName()[1] == '@')
{
segment.SetName("[?" + Sharpen.Runtime.Substring(segment.GetName(), 2));
if (!segment.GetName().StartsWith("[?xml:lang="))
{
throw new XMPException("Only xml:lang allowed with '@'", XMPErrorConstants.Badxpath);
}
}
if (segment.GetName()[1] == '?')
{
pos.nameStart++;
segment.SetKind(XMPPath.QualSelectorStep);
VerifyQualName(Sharpen.Runtime.Substring(pos.path, pos.nameStart, pos.nameEnd));
}
}
}
expandedXPath.Add(segment);
}
return expandedXPath;
}
/// <summary>Constructor with optionsl initial values.</summary>
/// <remarks>
/// Constructor with optionsl initial values. If <code>propName</code> is provided,
/// <code>schemaNS</code> has also be provided.
/// </remarks>
/// <param name="xmp">the iterated metadata object.</param>
/// <param name="schemaNS">the iteration is reduced to this schema (optional)</param>
/// <param name="propPath">the iteration is redurce to this property within the <code>schemaNS</code></param>
/// <param name="options">
/// advanced iteration options, see
/// <see cref="Com.Adobe.Xmp.Options.IteratorOptions"/>
/// </param>
/// <exception cref="Com.Adobe.Xmp.XMPException">If the node defined by the paramters is not existing.</exception>
public XMPIteratorImpl(XMPMetaImpl xmp, string schemaNS, string propPath, IteratorOptions options)
{
// make sure that options is defined at least with defaults
this.options = options != null ? options : new IteratorOptions();
// the start node of the iteration depending on the schema and property filter
XMPNode startNode = null;
string initialPath = null;
bool baseSchema = schemaNS != null && schemaNS.Length > 0;
bool baseProperty = propPath != null && propPath.Length > 0;
if (!baseSchema && !baseProperty)
{
// complete tree will be iterated
startNode = xmp.GetRoot();
}
else
{
if (baseSchema && baseProperty)
{
// Schema and property node provided
XMPPath path = XMPPathParser.ExpandXPath(schemaNS, propPath);
// base path is the prop path without the property leaf
XMPPath basePath = new XMPPath();
for (int i = 0; i < path.Size() - 1; i++)
{
basePath.Add(path.GetSegment(i));
}
startNode = XMPNodeUtils.FindNode(xmp.GetRoot(), path, false, null);
baseNS = schemaNS;
initialPath = basePath.ToString();
}
else
{
if (baseSchema && !baseProperty)
{
// Only Schema provided
startNode = XMPNodeUtils.FindSchemaNode(xmp.GetRoot(), schemaNS, false);
}
else
{
// !baseSchema && baseProperty
// No schema but property provided -> error
throw new XMPException("Schema namespace URI is required", XMPErrorConstants.Badschema);
}
}
}
// create iterator
if (startNode != null)
{
if (!this.options.IsJustChildren())
{
nodeIterator = new XMPIteratorImpl.NodeIterator(this, startNode, initialPath, 1);
}
else
{
nodeIterator = new XMPIteratorImpl.NodeIteratorChildren(this, startNode, initialPath);
}
}
else
{
// create null iterator
nodeIterator = Sharpen.Collections.EmptyList().Iterator();
}
}
/// <summary>
/// Parses the root node of an XMP Path, checks if namespace and prefix fit together
/// and resolve the property to the base property if it is an alias.
/// </summary>
/// <param name="schemaNS">the root namespace</param>
/// <param name="pos">the parsing position helper</param>
/// <param name="expandedXPath">the path to contribute to</param>
/// <exception cref="Com.Adobe.Xmp.XMPException">If the path is not valid.</exception>
private static void ParseRootNode(string schemaNS, PathPosition pos, XMPPath expandedXPath)
{
while (pos.stepEnd < pos.path.Length && "/[*".IndexOf(pos.path[pos.stepEnd]) < 0)
{
pos.stepEnd++;
}
if (pos.stepEnd == pos.stepBegin)
{
throw new XMPException("Empty initial XMPPath step", XMPErrorConstants.Badxpath);
}
string rootProp = VerifyXPathRoot(schemaNS, Sharpen.Runtime.Substring(pos.path, pos.stepBegin, pos.stepEnd));
XMPAliasInfo aliasInfo = XMPMetaFactory.GetSchemaRegistry().FindAlias(rootProp);
if (aliasInfo == null)
{
// add schema xpath step
expandedXPath.Add(new XMPPathSegment(schemaNS, XMPPath.SchemaNode));
XMPPathSegment rootStep = new XMPPathSegment(rootProp, XMPPath.StructFieldStep);
expandedXPath.Add(rootStep);
}
else
{
// add schema xpath step and base step of alias
expandedXPath.Add(new XMPPathSegment(aliasInfo.GetNamespace(), XMPPath.SchemaNode));
XMPPathSegment rootStep = new XMPPathSegment(VerifyXPathRoot(aliasInfo.GetNamespace(), aliasInfo.GetPropName()), XMPPath.StructFieldStep);
rootStep.SetAlias(true);
rootStep.SetAliasForm(aliasInfo.GetAliasForm().GetOptions());
expandedXPath.Add(rootStep);
if (aliasInfo.GetAliasForm().IsArrayAltText())
{
XMPPathSegment qualSelectorStep = new XMPPathSegment("[?xml:lang='x-default']", XMPPath.QualSelectorStep);
qualSelectorStep.SetAlias(true);
qualSelectorStep.SetAliasForm(aliasInfo.GetAliasForm().GetOptions());
expandedXPath.Add(qualSelectorStep);
}
else
{
if (aliasInfo.GetAliasForm().IsArray())
{
XMPPathSegment indexStep = new XMPPathSegment("[1]", XMPPath.ArrayIndexStep);
indexStep.SetAlias(true);
indexStep.SetAliasForm(aliasInfo.GetAliasForm().GetOptions());
expandedXPath.Add(indexStep);
}
}
}
}