lib/thread: rewrite _parent_or_toplevel to use depths

This is part 1/2 of changing the reparenting of alleged toplevel
messages to use a "deep" reference rather than just the first one
found.

diff --git a/lib/thread.cc b/lib/thread.cc
index bca1fb8f2c6a803a2663e6b4ca1b3b9d07b09edf..4f85a82934bbfe143d39b40cd05023e8b1893bd2 100644 (file)
--- a/lib/thread.cc
+++ b/lib/thread.cc
@@ -416,20 +416,40 @@ _parent_via_in_reply_to (notmuch_thread_t *thread, notmuch_message_t *message) {
 static void
 _parent_or_toplevel (notmuch_thread_t *thread, notmuch_message_t *message)
 {
-    bool found = false;
+    size_t max_depth = 0;
+    notmuch_message_t *new_parent;
     notmuch_message_t *parent = NULL;
     const notmuch_string_list_t *references =
        _notmuch_message_get_references (message);
+
+    THREAD_DEBUG("trying to reparent via references: %s\n",
+                    notmuch_message_get_message_id (message));
+
     for (notmuch_string_node_t *ref_node = references->head;
-        ! found && ref_node; ref_node = ref_node->next) {
-       if ((found = g_hash_table_lookup_extended (thread->message_hash,
-                                                  ref_node->string, NULL,
-                                                  (void **) &parent))) {
-           _notmuch_message_add_reply (parent, message);
+        ref_node; ref_node = ref_node->next) {
+       THREAD_DEBUG("checking reference=%s\n", ref_node->string);
+       if ((g_hash_table_lookup_extended (thread->message_hash,
+                                          ref_node->string, NULL,
+                                          (void **) &new_parent))) {
+           size_t new_depth = _notmuch_message_get_thread_depth (new_parent);
+           THREAD_DEBUG("got depth %lu\n", new_depth);
+           if (new_depth > max_depth || !parent) {
+               THREAD_DEBUG("adding at depth %lu parent=%s\n", new_depth, ref_node->string);
+               max_depth = new_depth;
+               parent = new_parent;
+           }
        }
     }
-    if (! found)
+    if (parent) {
+       THREAD_DEBUG("adding reply %s to parent=%s\n",
+                notmuch_message_get_message_id (message),
+                notmuch_message_get_message_id (parent));
+       _notmuch_message_add_reply (parent, message);
+    } else {
+       THREAD_DEBUG("adding as toplevel %s\n",
+                notmuch_message_get_message_id (message));
        _notmuch_message_list_add_message (thread->toplevel_list, message);
+    }
 }
 
 static void