moved transfer queueing out of watcher and into committer

This cleaned up the code quite a bit; now the committer just looks at the
Change to see if it's a change that needs to have a transfer queued for it.
If I later want to add dropping keys for files that were removed, or
something like that, this should make it straightforward.

This also fixes a bug. In direct mode, moving a file out of an archive
directory failed to start a transfer to get its content. The problem
was that the file had not been committed to git yet, and so the transfer
code didn't want to touch it, since fileKey failed to get its key.
Only starting transfers after a commit avoids this problem.

Assistant/Threads/Committer.hs

@@ -16,6 +16,7 @@ import Assistant.Commits
 import Assistant.Alert
 import Assistant.DaemonStatus
 import Assistant.TransferQueue
+import Assistant.Drop
 import Logs.Transfer
 import Logs.Location
 import qualified Annex.Queue
@@ -64,6 +65,7 @@ commitThread = namedThread "Committer" $ do
 						void $ alertWhile commitAlert $
 							liftAnnex commitStaged
 						recordCommit
+						mapM_ checkChangeContent readychanges
 					else refill readychanges
 			else refill changes
   where
@@ -196,7 +198,7 @@ handleAdds delayadd cs = returnWhen (null incomplete) $ do
 					key <- liftAnnex $ do
 						showStart "add" $ keyFilename ks
 						Command.Add.ingest $ Just ks
-					done (finishedChange change) (keyFilename ks) key
+					maybe failedingest (done change $ keyFilename ks) key
 	  where
 		{- Add errors tend to be transient and will be automatically
 		 - dealt with, so don't pass to the alert code. -}
@@ -204,10 +206,11 @@ handleAdds delayadd cs = returnWhen (null incomplete) $ do
 		ret _ = (True, Nothing)
 	add _ = return Nothing
 
-	done _ _ Nothing = do
+	failedingest = do
 		liftAnnex showEndFail
 		return Nothing
-	done change file (Just key) = do
+
+	done change file key = do
 		liftAnnex $ do
 			logStatus key InfoPresent
 			link <- ifM isDirect
@@ -217,8 +220,7 @@ handleAdds delayadd cs = returnWhen (null incomplete) $ do
 			whenM (pure DirWatcher.eventsCoalesce <||> isDirect) $ do
 				stageSymlink file =<< hashSymlink link
 				showEndOk
-		queueTransfers "newly added file" Next key (Just file) Upload
-		return $ Just change
+		return $ Just $ finishedChange change key
 
 	{- Check that the keysource's keyFilename still exists,
 	 - and is still a hard link to its contentLocation,
@@ -299,3 +301,22 @@ safeToAdd delayadd pending inprocess = do
 			tmpdir <- fromRepo gitAnnexTmpDir
 			liftIO $ Lsof.queryDir tmpdir
 		)
+
+{- After a Change is committed, queue any necessary transfers or drops
+ - of the content of the key.
+ -
+ - This is not done during the startup scan, because the expensive
+ - transfer scan does the same thing then.
+ -}
+checkChangeContent :: Change -> Assistant ()
+checkChangeContent (Change { changeInfo = i , changeFile = f }) =
+	case changeInfoKey i of
+		Nothing -> noop
+		Just k -> whenM (scanComplete <$> getDaemonStatus) $ do
+			present <- liftAnnex $ inAnnex k
+			if present
+				then queueTransfers "new file created" Next k (Just f) Upload
+				else queueTransfers "new or renamed file wanted" Next k (Just f) Download
+			handleDrops "file renamed" present k (Just f) Nothing
+checkChangeContent _ = noop
+