src/model.c: support node copying and changing attribute (e.g. ID) on the fly

src/model.c

@@ -38,6 +38,8 @@
 
 struct model_t *knownModels = NULL;
 
+static xmlHashTablePtr hashTable == NULL;
+
 /* -------------------------------------------------------------------------- */
 
 /**
@@ -48,11 +50,12 @@ struct model_t *knownModels = NULL;
  * @param currentPath The path to the current node.
  */
 void model_populate_hashtable (xmlNode *node,
-                              xmlHashTablePtr hashTable,
                               char *currentPath)
 {
     if (node == NULL) return;
 
+    assert(hashTable == NULL);
+
     // Skip text nodes and others that are not element nodes
     if (node->type != XML_ELEMENT_NODE) {
         model_populate_hashtable(node->next, hashTable, currentPath);
@@ -86,6 +89,8 @@ void model_populate_hashtable (xmlNode *node,
  */
 char* model_find_node_by_path (xmlNode *node, const char *path)
 {
+    assert(hashTable != NULL);
+
     return (xmlNodePtr)xmlHashLookup(hashTable, (const xmlChar *)path);
 }
 
@@ -97,10 +102,11 @@ char* model_find_node_by_path (xmlNode *node, const char *path)
  * @param newContent The new content to set for the node.
  * @return 1 if the node was found and modified, 0 otherwise.
  */
-int model_modify_node (xmlHashTablePtr hashTable,
-                      const char *path,
+int model_modify_node (const char *path,
                       const char *newContent)
 {
+    assert(hashTable != NULL);
+
     xmlNodePtr node = model_find_node_by_path(hashTable, path);
     if (node) {
         // Free the current content of the node, if any
@@ -120,10 +126,11 @@ int model_modify_node (xmlHashTablePtr hashTable,
  * @param attributeName The name of the attribute.
  * @return The value of the attribute, or NULL if not found.
  */
-char* model_get_attribute (xmlHashTablePtr hashTable,
-                           const char* nodePath,
+char* model_get_attribute (const char* nodePath,
                            const char* attributeName)
 {
+    assert(hashTable != NULL);
+
     xmlNodePtr node = (xmlNodePtr)xmlHashLookup(hashTable, (const xmlChar*)nodePath);
     if (node) {
         return getAttributeValue(node, attributeName);
@@ -141,11 +148,12 @@ char* model_get_attribute (xmlHashTablePtr hashTable,
  * @param attributeValue The value to set for the attribute.
  * @return 1 on success, 0 on failure.
  */
-int model_set_attribute (xmlHashTablePtr hashTable,
-                         const char* nodePath,
+int model_set_attribute (const char* nodePath,
                          const char* attributeName,
                          const char* attributeValue)
 {
+    assert(hashTable != NULL);
+
     xmlNodePtr node = (xmlNodePtr)xmlHashLookup(hashTable, (const xmlChar*)nodePath);
     if (node) {
         return setAttributeValue(node, attributeName, attributeValue);
@@ -154,6 +162,46 @@ int model_set_attribute (xmlHashTablePtr hashTable,
     }
 }
 
+/**
+ * Copies a node recursively to a new sibling node with a modified attribute and updates the hashtable.
+ *
+ * @param doc The document to which the nodes belong.
+ * @param node The node to copy.
+ * @param hashTable The hashtable for tracking nodes by path.
+ * @param originalNodePath The path of the original node in the hashtable.
+ * @param attributeName The name of the attribute to modify in the copied node.
+ * @param newAttributeValue The new value for the specified attribute in the copied node.
+ * @return The copied node with the modified attribute, or NULL on failure.
+ */
+xmlNodePtr model_copy_node(struct model_t *self,
+                           xmlNodePtr node,
+                           const char* originalNodePath,
+                           const char* attributeName,
+                           const char* newAttributeValue)
+{
+    assert(hashTable != NULL);
+
+    // Deep copy the node
+    xmlNodePtr copiedNode = xmlDocCopyNode(node, self->doc, 1);
+    if (copiedNode == NULL) {
+        return NULL; // Failed to copy
+    }
+
+    // Modify the specified attribute in the copied node
+    xmlSetProp(copiedNode, (const xmlChar*)attributeName, (const xmlChar*)newAttributeValue);
+
+    // Insert the copied node as the next sibling of the original node
+    xmlAddNextSibling(node, copiedNode);
+
+    // Calculate the new node's path.
+    char newPath[1024];
+    snprintf(newPath, sizeof(newPath), "%s_copy", originalNodePath);
+
+    // Update the hashtable with the new node's path
+    xmlHashAddEntry(hashTable, (const xmlChar*)newPath, copiedNode);
+
+    return copiedNode;
+}
 /* -------------------------------------------------------------------------- */
 
 char model_get_dim (struct model_t *self)