log_store_xml_get_events_for_file: replace edited messages.

This should support "b supersedes a ; c supersedes a" as well as
"b supersedes a ; c supersedes b"

Also, the list of returned events should only contain the most recent
version (for backwards compat with dumb log viewers, as suggested by
sjoerd).

* make a event_queue_add_text_event responsible for adding the event to
  the returned gqueue (replacing the event it supersedes as needed).
* use a GHashTable of {token: place to put message} for already edited
  messages, and check that first, then walk through the queue (starting
  at the most recent event) trying to find it.
* add a dummy event if none can be found.

1 files changed, 78 insertions, 6 deletions

diff --git a/telepathy-logger/log-store-xml.c b/telepathy-logger/log-store-xml.c
index 045cdb9..89dd08c 100644
--- a/telepathy-logger/log-store-xml.c
+++ b/telepathy-logger/log-store-xml.c
@@ -1261,6 +1261,68 @@ event_queue_insert_sorted_after (GQueue *events,
     }
 }
 
+static GList *
+event_queue_add_text_event (GQueue *events,
+    GList *index,
+    GHashTable *superseded_links,
+    TplTextEvent *event)
+{
+  GList *l = NULL;
+  const gchar *supersedes_token = tpl_text_event_get_supersedes_token (event);
+  TplTextEvent *dummy_event;
+
+  if (supersedes_token == NULL)
+    return event_queue_insert_sorted_after (events, index, TPL_EVENT (event));
+
+  l = g_hash_table_lookup (superseded_links, supersedes_token);
+  if (l != NULL)
+    {
+      tpl_text_event_add_supersedes (event, l->data);
+      g_object_unref (l->data);
+      l->data = event;
+      g_hash_table_insert (superseded_links, (gpointer) supersedes_token, l);
+      return index;
+    }
+
+  /* Search backwards from "now" and insert (but don't update "now") */
+  for (l = index; l != NULL; l = l->prev)
+    {
+      if (!tp_strdiff (tpl_text_event_get_message_token (l->data),
+          supersedes_token))
+        {
+          tpl_text_event_add_supersedes (event, l->data);
+          g_object_unref (l->data);
+          l->data = event;
+          g_hash_table_insert (superseded_links, (gpointer) supersedes_token, l);
+          return index;
+        }
+    }
+
+  DEBUG ("Can't find event %s (superseded by %s). "
+      "Better <s>drink my own piss</s> fake it.",
+      supersedes_token, tpl_text_event_get_message_token (event));
+
+  dummy_event = g_object_new (TPL_TYPE_TEXT_EVENT,
+      /* TplEvent */
+      "account", tpl_event_get_account (TPL_EVENT (event)),
+      /* MISSING: "channel-path", channel_path, */
+      "receiver", tpl_event_get_receiver (TPL_EVENT (event)),
+      "sender", tpl_event_get_sender (TPL_EVENT (event)),
+      "timestamp", tpl_event_get_timestamp (TPL_EVENT (event)),
+      /* TplTextEvent */
+      "message-type", tpl_text_event_get_message_type (event),
+      "message", "",
+      "message-token", supersedes_token,
+      NULL);
+
+  tpl_text_event_add_supersedes (event, dummy_event);
+  index = event_queue_insert_sorted_after (events, index,
+      TPL_EVENT (event));
+  g_hash_table_insert (superseded_links, (gpointer) supersedes_token,
+      index);
+  return index;
+}
+
 /* returns a Glist of TplEvent instances */
 static void
 log_store_xml_get_events_for_file (TplLogStoreXml *self,
@@ -1278,6 +1340,7 @@ log_store_xml_get_events_for_file (TplLogStoreXml *self,
   gchar *tmp;
   gchar *target_id;
   gchar *self_id;
+  GHashTable *supersedes_links;
   GError *error = NULL;
   guint num_events = 0;
   GList *index;
@@ -1340,6 +1403,11 @@ log_store_xml_get_events_for_file (TplLogStoreXml *self,
   g_free (dirname);
   g_free (tmp);
 
+  /* Temporary hash from borrowed supersedes-token to borrowed link in
+   * events, so that we can efficiently replace repeatedly superseded
+   * events as their replacements come in. */
+  supersedes_links = g_hash_table_new (g_str_hash, g_str_equal);
+
   /* Now get the events. */
   index = events->head;
   for (node = log_node->children; node; node = node->next)
@@ -1348,15 +1416,18 @@ log_store_xml_get_events_for_file (TplLogStoreXml *self,
 
       if (type == TPL_TYPE_TEXT_EVENT
           && strcmp ((const gchar *) node->name, "message") == 0)
-        event = parse_text_node (self, node, is_room, target_id, self_id,
-            account);
+        {
+          event = parse_text_node (self, node, is_room, target_id, self_id,
+              account);
+          index = event_queue_add_text_event (events, index,
+              supersedes_links, TPL_TEXT_EVENT (event));
+          num_events++;
+        }
       else if (type == TPL_TYPE_CALL_EVENT
           && strcmp ((const char*) node->name, "call") == 0)
-        event = parse_call_node (self, node, is_room, target_id, self_id,
-            account);
-
-      if (event != NULL)
         {
+          event = parse_call_node (self, node, is_room, target_id, self_id,
+              account);
           index = event_queue_insert_sorted_after (events, index, event);
           num_events++;
         }
@@ -1367,6 +1438,7 @@ log_store_xml_get_events_for_file (TplLogStoreXml *self,
   g_free (target_id);
   xmlFreeDoc (doc);
   xmlFreeParserCtxt (ctxt);
+  g_hash_table_destroy (supersedes_links);
 }