[PATCH 07/15] lib: calculate message depth in thread

[David Bremner <david@tethera.net>]

This will be used in reparenting messages without useful in-reply-to,
but with useful references
---
 lib/message.cc        | 23 +++++++++++++++++++++++
 lib/notmuch-private.h |  5 +++++
 2 files changed, 28 insertions(+)

diff --git a/lib/message.cc b/lib/message.cc
index db5ce0a2..3c547298 100644
--- a/lib/message.cc
+++ b/lib/message.cc
@@ -32,6 +32,7 @@ struct _notmuch_message {
     int frozen;
     char *message_id;
     char *thread_id;
+    size_t thread_depth;
     char *in_reply_to;
     notmuch_string_list_t *tag_list;
     notmuch_string_list_t *filename_term_list;
@@ -118,6 +119,9 @@ _notmuch_message_create_for_document (const void *talloc_owner,
     /* the message is initially not synchronized with Xapian */
     message->last_view = 0;
 
+    /* Calculated after the thread structure is computed */
+    message->thread_depth = 0;
+
     /* Each of these will be lazily created as needed. */
     message->message_id = NULL;
     message->thread_id = NULL;
@@ -599,6 +603,25 @@ _notmuch_message_add_reply (notmuch_message_t *message,
     _notmuch_message_list_add_message (message->replies, reply);
 }
 
+size_t
+_notmuch_message_get_thread_depth (notmuch_message_t *message) {
+    return message->thread_depth;
+}
+
+void
+_notmuch_message_label_depths (notmuch_message_t *message,
+			       size_t depth)
+{
+    message->thread_depth = depth;
+
+    for (notmuch_messages_t *messages = _notmuch_messages_create (message->replies);
+	 notmuch_messages_valid (messages);
+	 notmuch_messages_move_to_next (messages)) {
+	notmuch_message_t *child = notmuch_messages_get (messages);
+	_notmuch_message_label_depths (child, depth+1);
+    }
+}
+
 const notmuch_string_list_t *
 _notmuch_message_get_references (notmuch_message_t *message)
 {
diff --git a/lib/notmuch-private.h b/lib/notmuch-private.h
index 7603e1f4..083fc013 100644
--- a/lib/notmuch-private.h
+++ b/lib/notmuch-private.h
@@ -539,6 +539,11 @@ _notmuch_message_remove_unprefixed_terms (notmuch_message_t *message);
 const char *
 _notmuch_message_get_thread_id_only(notmuch_message_t *message);
 
+size_t _notmuch_message_get_thread_depth (notmuch_message_t *message);
+
+void
+_notmuch_message_label_depths (notmuch_message_t *message,
+			       size_t depth);
 void
 _notmuch_message_sort_subtree (notmuch_message_t *message);
 
-- 
2.18.0