HTML: track changes on DOM Elements

2 files changed, 90 insertions, 6 deletions

diff --git a/content/handlers/html/box/manager.c b/content/handlers/html/box/manager.c
index d8dadf300..6d558e41e 100644
--- a/content/handlers/html/box/manager.c
+++ b/content/handlers/html/box/manager.c
@@ -6,6 +6,17 @@
 #include "utils/corestrings.h"
 #include "utils/log.h"
 
+/* Flags for DOM Element nodes */
+
+#define BM_DOM_FLAG_STRUCTURE_CHANGED		0x00000001
+/* Document structure has changed at this node: recompute style information
+ * for it, its descendants, its subsequent siblings, and their descendants.
+ * If styles have changed, rebuild box subtree */
+
+#define BM_DOM_FLAG_TEXT_CONTENTS_CHANGED	0x00000002
+/* Text contents of this node have changed: rebuild box subtree */
+
+
 struct box_manager
 {
 	dom_document *doc;
@@ -198,13 +209,65 @@ _find_parent_element_or_document(dom_node *target)
 	return parent;
 }
 
+static dom_exception
+_foreach_element_sibling(dom_node *cur,
+		dom_exception (*cb)(dom_node *, void *), void *pw)
+{
+	dom_node *sibling = NULL;
+	dom_exception exc;
+
+	dom_node_ref(cur);
+
+	do {
+		exc = dom_node_get_next_sibling(cur, &sibling);
+		dom_node_unref(cur);
+		cur = sibling;
+		sibling = NULL;
+
+		if (exc == DOM_NO_ERR && cur != NULL) {
+			dom_node_type sibling_type;
+
+			exc = dom_node_get_node_type(cur, &sibling_type);
+			if (exc == DOM_NO_ERR &&
+					sibling_type == DOM_ELEMENT_NODE) {
+				exc = cb(cur, pw);
+			}
+		}
+	} while (exc == DOM_NO_ERR && cur != NULL);
+
+	dom_node_unref(cur);
+
+	return exc;
+}
+
+static dom_exception
+_set_node_flags(dom_node *node, void *pw)
+{
+	uintptr_t flags_to_set = (uintptr_t) pw;
+	uintptr_t node_flags = 0;
+	dom_exception exc;
+
+	exc = dom_node_get_user_data(node,
+			corestring_dom___ns_key_bm_node_data,
+			(void **) &node_flags);
+	if (exc == DOM_NO_ERR) {
+		node_flags |= flags_to_set;
+		exc = dom_node_set_user_data(node,
+				corestring_dom___ns_key_bm_node_data,
+				(void *) node_flags,
+				NULL,
+				(void **) &node_flags);
+	}
+	return exc;
+}
+
 static void
 box_manager_handle_dom_event(dom_event *evt, void *pw)
 {
 	box_manager *mgr = pw;
 	dom_node *parent = NULL;
 	dom_event_target *target = NULL;
-	dom_node_type node_type;
+	dom_node_type target_type;
 	dom_string *evt_type = NULL, *computed_type = NULL;
 	dom_exception exc;
 
@@ -244,9 +307,9 @@ box_manager_handle_dom_event(dom_event *evt, void *pw)
 	}
 
 	/* 3. The event target must be an Element or Text node */
-	exc = dom_node_get_node_type(target, &node_type);
-	if (exc != DOM_NO_ERR || (node_type != DOM_ELEMENT_NODE &&
-			node_type != DOM_TEXT_NODE)) {
+	exc = dom_node_get_node_type(target, &target_type);
+	if (exc != DOM_NO_ERR || (target_type != DOM_ELEMENT_NODE &&
+			target_type != DOM_TEXT_NODE)) {
 		dom_node_unref(target);
 		return;
 	}
@@ -258,9 +321,29 @@ box_manager_handle_dom_event(dom_event *evt, void *pw)
 		return;
 	}
 
-	/* 5. mark target dirty */
-	// XXX: we probably want a uintptr_t's worth of user data containing flags for now
+	/* 5. update node flags */
+	if (target_type == DOM_ELEMENT_NODE) {
+		/* Mark nodes as structurally changed */
+		if (computed_type == corestring_dom_DOMNodeRemoved) {
+			/* All subsequent sibling elements */
+			exc = _foreach_element_sibling((dom_node *) target,
+				_set_node_flags,
+				(void *) BM_DOM_FLAG_STRUCTURE_CHANGED);
+		} else {
+			/* Just target itself */
+			exc = _set_node_flags((dom_node *) target,
+				(void *) BM_DOM_FLAG_STRUCTURE_CHANGED);
+		}
+	} else if (target_type == DOM_TEXT_NODE) {
+		/* Mark parent as text content changed */
+		exc = _set_node_flags((dom_node *) parent,
+				(void *) BM_DOM_FLAG_TEXT_CONTENTS_CHANGED);
+	}
 	dom_node_unref(target);
+	if (exc != DOM_NO_ERR) {
+		dom_node_unref(parent);
+		return;
+	}
 
 	/* 6. Capture parent node (ensuring we keep a ref) into list of
 	 * pending events. */
diff --git a/utils/corestringlist.h b/utils/corestringlist.h
index ff8e49a35..b96039b41 100644
--- a/utils/corestringlist.h
+++ b/utils/corestringlist.h
@@ -366,6 +366,7 @@ CORESTRING_DOM_STRING(wheel);
 CORESTRING_DOM_STRING(sort);
 CORESTRING_DOM_STRING(toggle);
 /* DOM userdata keys, not really CSS */
+CORESTRING_DOM_STRING(__ns_key_bm_node_data);
 CORESTRING_DOM_STRING(__ns_key_box_node_data);
 CORESTRING_DOM_STRING(__ns_key_libcss_node_data);
 CORESTRING_DOM_STRING(__ns_key_file_name_node_data);