changed semantics of default field, now referring to the only TREE field.

4 files changed, 198 insertions, 191 deletions

diff --git a/src/core/model/Domain.cpp b/src/core/model/Domain.cpp
index 787f1ff..3fb525f 100644
--- a/src/core/model/Domain.cpp
+++ b/src/core/model/Domain.cpp
@@ -173,20 +173,38 @@ bool Descriptor::doValidate(Logger &logger) const
 	}
 	// ensure that no attribute with the key "name" exists.
 	if (attributesDescriptor == nullptr) {
-		logger.error("This Descriptor has no Attribute specification!");
+		logger.error(std::string("Descriptor \"") + getName() +
+		             "\" has no Attribute specification!");
 		valid = false;
 	} else {
 		if (attributesDescriptor->hasAttribute("name")) {
 			logger.error(
-			    "This Descriptor has an attribute \"name\" which is a reserved "
-			    "word!");
+			    std::string("Descriptor \"") + getName() +
+			    "\" has an attribute \"name\" which is a reserved word!");
 			valid = false;
 		}
 		valid = valid & attributesDescriptor->validate(logger);
 	}
+	// check that only one FieldDescriptor is of type TREE.
+	auto fds = Descriptor::getFieldDescriptors();
+	bool hasTREE = false;
+	for (auto fd : fds) {
+		if (fd->getFieldType() == FieldDescriptor::FieldType::TREE) {
+			if (!hasTREE) {
+				hasTREE = true;
+			} else {
+				logger.error(
+				    std::string("Descriptor \"") + getName() +
+				        "\" has multiple TREE fields, which is not permitted",
+				    *fd);
+				valid = false;
+				break;
+			}
+		}
+	}
 
 	// check attributes and the FieldDescriptors
-	return valid & continueValidationCheckDuplicates(fieldDescriptors, logger);
+	return valid & continueValidationCheckDuplicates(fds, logger);
 }
 
 std::vector<Rooted<Node>> Descriptor::pathTo(
@@ -259,18 +277,39 @@ bool Descriptor::continuePath(Handle<StructuredClass> target,
 	return found;
 }
 
-ssize_t Descriptor::getFieldDescriptorIndex(const std::string &name) const
+static ssize_t getFieldDescriptorIndex(const NodeVector<FieldDescriptor> &fds,
+                                       const std::string &name)
 {
-	size_t f = 0;
-	for (auto &fd : getFieldDescriptors()) {
-		if (fd->getName() == name) {
+	if (fds.empty()) {
+		return -1;
+	}
+
+	if (name == DEFAULT_FIELD_NAME) {
+		if (fds.back()->getFieldType() == FieldDescriptor::FieldType::TREE) {
+			return fds.size() - 1;
+		} else {
+			/* The last field has to be the TREE field. If the last field does
+			 * not have the FieldType TREE no TREE-field exists at all. So we
+			 * return -1.
+			 */
+			return -1;
+		}
+	}
+
+	for (size_t f = 0; f < fds.size(); f++) {
+		if (fds[f]->getName() == name) {
 			return f;
 		}
-		f++;
 	}
 	return -1;
 }
 
+ssize_t Descriptor::getFieldDescriptorIndex(const std::string &name) const
+{
+	NodeVector<FieldDescriptor> fds = getFieldDescriptors();
+	return ousia::getFieldDescriptorIndex(fds, name);
+}
+
 ssize_t Descriptor::getFieldDescriptorIndex(Handle<FieldDescriptor> fd) const
 {
 	size_t f = 0;
@@ -286,33 +325,54 @@ ssize_t Descriptor::getFieldDescriptorIndex(Handle<FieldDescriptor> fd) const
 Rooted<FieldDescriptor> Descriptor::getFieldDescriptor(
     const std::string &name) const
 {
-	for (auto &fd : getFieldDescriptors()) {
-		if (fd->getName() == name) {
-			return fd;
-		}
+	NodeVector<FieldDescriptor> fds = getFieldDescriptors();
+	ssize_t idx = ousia::getFieldDescriptorIndex(fds, name);
+	if (idx != -1) {
+		return fds[idx];
+	} else {
+		return nullptr;
 	}
-	return nullptr;
 }
 
-void Descriptor::addFieldDescriptor(Handle<FieldDescriptor> fd)
+void Descriptor::addAndSortFieldDescriptor(Handle<FieldDescriptor> fd,
+                                           Logger &logger)
 {
 	// only add it if we need to.
-	if (fieldDescriptors.find(fd) == fieldDescriptors.end()) {
+	auto fds = getFieldDescriptors();
+	if (fds.find(fd) == fds.end()) {
 		invalidate();
-		fieldDescriptors.push_back(fd);
+		// check if the previous field is a tree field already.
+		if (!fds.empty() &&
+		    fds.back()->getFieldType() == FieldDescriptor::FieldType::TREE &&
+		    fd->getFieldType() != FieldDescriptor::FieldType::TREE) {
+			// if so we add the new field before the TREE field and log a
+			// warning.
+
+			logger.warning(
+			    std::string("Field \"") + fd->getName() +
+			        "\" was declared after main field \"" +
+			        fds.back()->getName() +
+			        "\". The order of fields was changed to make the "
+			        "main field the last field.",
+			    *fd);
+			fieldDescriptors.insert(fieldDescriptors.end() - 1, fd);
+		} else {
+			fieldDescriptors.push_back(fd);
+		}
 	}
+}
+
+void Descriptor::addFieldDescriptor(Handle<FieldDescriptor> fd, Logger &logger)
+{
+	addAndSortFieldDescriptor(fd, logger);
 	if (fd->getParent() == nullptr) {
 		fd->setParent(this);
 	}
 }
 
-void Descriptor::moveFieldDescriptor(Handle<FieldDescriptor> fd)
+void Descriptor::moveFieldDescriptor(Handle<FieldDescriptor> fd, Logger &logger)
 {
-	// only add it if we need to.
-	if (fieldDescriptors.find(fd) == fieldDescriptors.end()) {
-		invalidate();
-		fieldDescriptors.push_back(fd);
-	}
+	addAndSortFieldDescriptor(fd, logger);
 	Handle<Managed> par = fd->getParent();
 	if (par != this) {
 		if (par != nullptr) {
@@ -494,18 +554,35 @@ void StructuredClass::removeSubclass(Handle<StructuredClass> sc, Logger &logger)
 	sc->setSuperclass(nullptr, logger);
 }
 
-const void StructuredClass::gatherFieldDescriptors(
+void StructuredClass::gatherFieldDescriptors(
     NodeVector<FieldDescriptor> &current,
-    std::set<std::string> &overriddenFields) const
+    std::set<std::string> &overriddenFields, bool hasTREE) const
 {
 	// append all FieldDescriptors that are not overridden.
 	for (auto &f : Descriptor::getFieldDescriptors()) {
 		if (overriddenFields.insert(f->getName()).second) {
-			current.push_back(f);
+			bool isTREE = f->getFieldType() == FieldDescriptor::FieldType::TREE;
+			if (hasTREE) {
+				if (!isTREE) {
+					/*
+					 * If we already have a tree field it has to be at the end
+					 * of the current vector. So ensure that all new non-TREE
+					 * fields are inserted before the TREE field such that after
+					 * this method the TREE field is still at the end.
+					 */
+					current.insert(current.end() - 1, f);
+				}
+			} else {
+				if (isTREE) {
+					hasTREE = true;
+				}
+				current.push_back(f);
+			}
 		}
 	}
+	// if we have a superclass, go there.
 	if (superclass != nullptr) {
-		superclass->gatherFieldDescriptors(current, overriddenFields);
+		superclass->gatherFieldDescriptors(current, overriddenFields, hasTREE);
 	}
 }
 
@@ -514,7 +591,7 @@ NodeVector<FieldDescriptor> StructuredClass::getFieldDescriptors() const
 	// in this case we return a NodeVector of Rooted entries without owner.
 	NodeVector<FieldDescriptor> vec;
 	std::set<std::string> overriddenFields;
-	gatherFieldDescriptors(vec, overriddenFields);
+	gatherFieldDescriptors(vec, overriddenFields, false);
 	return vec;
 }
 
diff --git a/src/core/model/Domain.hpp b/src/core/model/Domain.hpp
index 241c25d..43661c2 100644
--- a/src/core/model/Domain.hpp
+++ b/src/core/model/Domain.hpp
@@ -34,74 +34,46 @@
  *
  * \code{.xml}
  * <domain name="book">
- * 	<structs>
- * 		<struct name="book" cardinality="1" isRoot="true">
- * 			<fields>
- * 				<field>
- * 					<children>
- * 						<child name="book.chapter"/>
- * 						<child name="book.paragraph"/>
- * 					</children>
- * 				</field>
- * 			</fields>
- * 		</struct>
- * 		<struct name="chapter">
- * 			<fields>
- * 				<field>
- * 					<children>
- * 						<child name="book.section"/>
- * 						<child name="book.paragraph"/>
- * 					</children>
- * 				</field>
- * 			</fields>
- * 		</struct>
- * 		<struct name="section">
- * 			<fields>
- * 				<field>
- * 					<children>
- * 						<child name="book.subsection"/>
- * 						<child name="book.paragraph"/>
- * 					</children>
- * 				</field>
- * 			</fields>
- * 		</struct>
- * 		<struct name="subsection">
- * 			<fields>
- * 				<field>
- * 					<children>
- * 						<child name="book.paragraph"/>
- * 					</children>
- * 				</field>
- * 			</fields>
- * 		</struct>
- * 		<struct name="paragraph" transparent="true" role="paragraph">
- * 			<fields>
- * 				<field>
- * 					<children>
- * 						<child name="book.text"/>
- * 					</children>
- * 				</field>
- * 			</fields>
- * 		</struct>
- * 		<struct name="text" transparent="true" role="text">
- * 			<fields>
- * 				<field name="content" type="PRIMITIVE" primitiveType="string"/>
- * 			</fields>
- * 		</struct>
- * 	</structs>
+ * 	<struct name="book" cardinality="1" isRoot="true">
+ * 		<field>
+ * 			<childRef ref="book.chapter"/>
+ * 			<childRef ref="book.paragraph"/>
+ * 		</field>
+ * 	</struct>
+ * 	<struct name="chapter">
+ * 		<field>
+ * 			<childRef ref="book.section"/>
+ * 			<childRef ref="book.paragraph"/>
+ * 		</field>
+ * 	</struct>
+ * 	<struct name="section">
+ * 		<field>
+ * 			<childRef ref="book.subsection"/>
+ * 			<childRef ref="book.paragraph"/>
+ * 		</field>
+ * 	</struct>
+ * 	<struct name="subsection">
+ * 		<field>
+ * 			<childRef ref="book.paragraph"/>
+ * 		</field>
+ * 	</struct>
+ * 	<struct name="paragraph" transparent="true">
+ * 		<field>
+ * 			<childRef ref="book.text"/>
+ * 		</field>
+ * 	</struct>
+ * 	<struct name="text" transparent="true">
+ * 		<primitive type="string"/>
+ * 	</struct>
  * </domain>
  * \endcode
  *
  * Note that we define one field as the TREE (meaning the main or default
  * document structure) and one mearly as SUBTREE, relating to supporting
  * information. You are not allowed to define more than one field of type
- * "TREE". Accordingly for each StructuredClass in the main TREE there must be
- * at least one possible primitive child or one TREE field. Otherwise the
- * grammar would be nonterminal. For SUBTREE fields no children may define a
- * TREE field and at least one permitted child must exist, either primitive or
- * as another StructuredClass.
+ * "TREE".
  *
- * The translation to context free grammars is as follows:
+ * The translation to a context free grammar is as follows:
  *
  * \code{.txt}
  * BOOK              := <book> BOOK_TREE </book>
@@ -128,21 +100,14 @@
  *
  * \code{.xml}
  * <domain name="headings">
- * 	<head>
- * 		<import rel="domain" src="book.oxm"/>
- * 	</head>
- * 	<structs>
- * 		<struct name="heading" cardinality="0-1" transparent="true">
- * 			<parents>
- * 				<parent name="book.book">
- * 					<field name="heading" type="SUBTREE"/>
- * 				</parent>
- * 				...
- * 			</parents>
- * 			<fields>
- * 				<fieldRef name="book.paragraph.">
- * 			</fields>
- * 	</structs>
+ *	<import rel="domain" src="./book_domain.osxml"/>
+ * 	<struct name="heading" cardinality="1" transparent="true">
+ * 		<parentRef ref="book.book">
+ * 			<field name="heading" isSubtree="true" optional="true"/>
+ * 		</parentRef>
+ * 		...
+ * 		<fieldRef name="book.paragraph.">
+ * 	</struct>
  * </domain>
  * \endcode
  *
@@ -161,36 +126,36 @@
  *
  * \code{.xml}
  * <domain name="comments">
- * 	<head>
- * 		<import rel="domain" src="book.oxm"/>
- * 	</head>
- * 	<annos>
- * 		<anno name="comment">
- * 			<fields>
- * 				<field name="replies" type="SUBTREE">
- * 					<children>
- * 						<child name="reply"/>
- * 					</children>
- * 				</field>
- * 			</fields>
- * 		</anno>
- * 	</annos>
- * 	<structs>
- * 		<struct name="reply">
- * 			<fields>
- * 				<field name="replies" type="SUBTREE">
- * 					<children>
- * 						<child name="reply"/>
- * 					</children>
- * 				</field>
- * 				<field name="content" type="SUBTREE">
- * 					<children>
- * 						<child name="book.paragraph"/>
- * 					</children>
- * 				</field>
- * 			</fields>
- * 		</struct>
- * 	</structs>
+ *	<import rel="domain" src="./book_domain.osxml"/>
+ *
+ *	<annotation name="comment">
+ *		<field name="content" isSubtree="true">
+ *			<childRef ref="book.paragraph"/>
+ *		</field>
+ *		<field name="replies" isSubtree="true">
+ *			<childRef ref="reply"/>
+ *		</field>
+ *	</annotation>
+ *
+ *	<struct name="comment">
+ *		<field name="content">
+ *			<childRef ref="book.paragraph"/>
+ *		</field>
+ *		<field name="replies" isSubtree="true">
+ *			<childRef ref="reply"/>
+ *		</field>
+ *		<parentRef ref="book.paragraph">
+ *			<fieldRef ref="$default"/>
+ *		</parentRef>
+ *	</struct>
+ *	<struct name="reply">
+ *		<field name="content" isSubtree="true">
+ *			<childRef ref="book.paragraph"/>
+ *		</field>
+ *		<field name="replies" isSubtree="true">
+ *			<childRef ref="reply"/>
+ *		</field>
+ *	</struct>
  * </domain>
  * \endcode
  *
@@ -227,25 +192,15 @@ static const std::string DEFAULT_FIELD_NAME = "$default";
  * accordingly typed content without further descending in the Structure
  * Hierarchy.
  *
- * As an example consider the "paragraph" StructuredClass, which might allow
+ * As an example consider the "text" StructuredClass, which might allow
  * the actual text content. Here is the according XML:
  *
  * \code{.xml}
- * <struct name="paragraph" transparent="true" role="paragraph">
- * 	<fields>
- * 		<field>
- * 			<children>
- * 				<child name="book.text"/>
- * 			</children>
- * 		</field>
- * 	</fields>
- * </struct>
+ * 	<struct name="text" transparent="true">
+ * 		<primitive type="string"/>
+ * 	</struct>
  * \endcode
  *
- * Accordingly the primitiveType field of a FieldDescriptor may only be
- * defined if the type is set to "PRIMITIVE". If the type is something else
- * at least one child must be defined and the primitiveType remains in an
- * undefined state.
  */
 class FieldDescriptor : public Node {
 	friend Descriptor;
@@ -370,11 +325,11 @@ public:
 	}
 
 	/**
-	 * Returns true if and only if the type of this field is PRIMITIVE.
+	 * Returns if this field is primitive.
 	 *
-	 * @return true if and only if the type of this field is PRIMITIVE.
+	 * @return true if and only if this field is primitive.
 	 */
-	bool isPrimitive() const { return fieldType == FieldType::PRIMITIVE; }
+	bool isPrimitive() const { return primitive; }
 
 	/**
 	 * Returns the primitive type of this field, which is only allowed to be
@@ -449,8 +404,10 @@ private:
 	Owned<StructType> attributesDescriptor;
 	NodeVector<FieldDescriptor> fieldDescriptors;
 
-	bool continuePath(Handle<StructuredClass> target,
-	                  std::vector<Rooted<Node>> &path) const;
+	bool continuePath(Handle<StructuredClass> target, NodeVector<Node> &path,
+	                  bool start) const;
+
+	void addAndSortFieldDescriptor(Handle<FieldDescriptor> fd, Logger &logger);
 
 protected:
 	void doResolve(ResolutionState &state) override;
@@ -539,20 +496,7 @@ public:
 	 *
 	 * @param fd is a FieldDescriptor.
 	 */
-	void addFieldDescriptor(Handle<FieldDescriptor> fd);
-
-	/**
-	 * Adds the given FieldDescriptors to this Descriptor. This also sets the
-	 * parent of each given FieldDescriptor if it is not set yet.
-	 *
-	 * @param fds are FieldDescriptors.
-	 */
-	void addFieldDescriptors(const std::vector<Handle<FieldDescriptor>> &fds)
-	{
-		for (Handle<FieldDescriptor> fd : fds) {
-			addFieldDescriptor(fd);
-		}
-	}
+	void addFieldDescriptor(Handle<FieldDescriptor> fd, Logger &logger);
 
 	/**
 	 * Adds the given FieldDescriptor to this Descriptor. This also sets the
@@ -561,21 +505,7 @@ public:
 	 *
 	 * @param fd is a FieldDescriptor.
 	 */
-	void moveFieldDescriptor(Handle<FieldDescriptor> fd);
-
-	/**
-	 * Adds the given FieldDescriptors to this Descriptor. This also sets the
-	 * parent of each given FieldDescriptor if it is not set to this Descriptor
-	 * already and removes it from the old parent Descriptor.
-	 *
-	 * @param fds are FieldDescriptors.
-	 */
-	void moveFieldDescriptors(const std::vector<Handle<FieldDescriptor>> &fds)
-	{
-		for (Handle<FieldDescriptor> fd : fds) {
-			moveFieldDescriptor(fd);
-		}
-	}
+	void moveFieldDescriptor(Handle<FieldDescriptor> fd, Logger &logger);
 
 	/**
 	 * Copies a FieldDescriptor that belongs to another Descriptor to this
@@ -583,7 +513,7 @@ public:
 	 *
 	 * @param fd some FieldDescriptor belonging to another Descriptor.
 	 */
-	void copyFieldDescriptor(Handle<FieldDescriptor> fd);
+	void copyFieldDescriptor(Handle<FieldDescriptor> fd, Logger &logger);
 
 	/**
 	 * Removes the given FieldDescriptor from this Descriptor. This also sets
@@ -751,9 +681,9 @@ private:
 	/**
 	 * Helper method for getFieldDescriptors.
 	 */
-	const void gatherFieldDescriptors(
-	    NodeVector<FieldDescriptor> &current,
-	    std::set<std::string> &overriddenFields) const;
+	void gatherFieldDescriptors(NodeVector<FieldDescriptor> &current,
+	                            std::set<std::string> &overriddenFields,
+	                            bool hasTREE) const;
 
 protected:
 	bool doValidate(Logger &logger) const override;
diff --git a/src/plugins/html/DemoOutput.cpp b/src/plugins/html/DemoOutput.cpp
index d041c1d..cb34cbe 100644
--- a/src/plugins/html/DemoOutput.cpp
+++ b/src/plugins/html/DemoOutput.cpp
@@ -324,7 +324,7 @@ Rooted<xml::Element> DemoHTMLTransformer::transformParagraph(
 		if (childDescriptorName == "text") {
 			Handle<DocumentPrimitive> primitive =
 			    t->getField()[0].cast<DocumentPrimitive>();
-			if (primitive.isNull()) {
+			if (primitive == nullptr) {
 				throw OusiaException("Text field is not primitive!");
 			}
 			current->addChild(new xml::Text(
diff --git a/src/plugins/xml/XmlParser.cpp b/src/plugins/xml/XmlParser.cpp
index 22498f4..d7efa4d 100644
--- a/src/plugins/xml/XmlParser.cpp
+++ b/src/plugins/xml/XmlParser.cpp
@@ -603,7 +603,7 @@ public:
 		    [](Handle<Node> field, Handle<Node> parent, Logger &logger) {
 			    if (field != nullptr) {
 				    parent.cast<StructuredClass>()->addFieldDescriptor(
-				        field.cast<FieldDescriptor>());
+				        field.cast<FieldDescriptor>(), logger);
 			    }
 			});
 	}
@@ -969,7 +969,7 @@ static const ParserState DomainField =
         .parents({&DomainStruct, &DomainAnnotation})
         .createdNodeType(&RttiTypes::FieldDescriptor)
         .elementHandler(DomainFieldHandler::create)
-        .arguments({Argument::String("name", DEFAULT_FIELD_NAME),
+        .arguments({Argument::String("name", ""),
                     Argument::Bool("isSubtree", false),
                     Argument::Bool("optional", false)});
 
@@ -985,7 +985,7 @@ static const ParserState DomainStructPrimitive =
         .parents({&DomainStruct, &DomainAnnotation})
         .createdNodeType(&RttiTypes::FieldDescriptor)
         .elementHandler(DomainPrimitiveHandler::create)
-        .arguments({Argument::String("name", DEFAULT_FIELD_NAME),
+        .arguments({Argument::String("name", ""),
                     Argument::Bool("isSubtree", false),
                     Argument::Bool("optional", false),
                     Argument::String("type")});
@@ -1008,7 +1008,7 @@ static const ParserState DomainStructParentField =
         .parent(&DomainStructParent)
         .createdNodeType(&RttiTypes::FieldDescriptor)
         .elementHandler(DomainParentFieldHandler::create)
-        .arguments({Argument::String("name", DEFAULT_FIELD_NAME),
+        .arguments({Argument::String("name", ""),
                     Argument::Bool("isSubtree", false),
                     Argument::Bool("optional", false)});