almost finished with applySimCommand

Added checks that repo names are ones that have been added to the sim.

Implemented preferred content etc setting. It does not need to parse the
expression in applySimCommand, instead that can be done when running the
sim. This keeps it pure.

But, it can't be entirely pure because of CommandAddTree. So made it
return an Annex action when necessary.

Moved makeMatcher into Annex.FileMatcher in preparation for using it,
but it's not used yet. Also moved checkPreferredContentExpression.

Annex/FileMatcher.hs

@@ -13,10 +13,12 @@ module Annex.FileMatcher (
 	checkFileMatcher',
 	checkMatcher,
 	checkMatcher',
+	makeMatcher,
 	matchAll,
 	PreferredContentData(..),
 	preferredContentTokens,
 	preferredContentParser,
+	checkPreferredContentExpression,
 	ParseToken,
 	parsedToMatcher,
 	mkMatchExpressionParser,
@@ -41,6 +43,8 @@ import Annex.SpecialRemote.Config (preferreddirField)
 import Git.FilePath
 import Types.Remote (RemoteConfig)
 import Types.ProposedAccepted
+import Types.StandardGroups
+import Logs.Group
 import Annex.CheckAttr
 import Annex.RepoSize.LiveUpdate
 import qualified Git.Config
@@ -302,3 +306,56 @@ call desc (Right sub) = Right $ Operation $ MatchFiles
 	, matchDesc = matchDescSimple desc
 	}
 call _ (Left err) = Left err
+
+makeMatcher
+	:: GroupMap
+	-> M.Map UUID RemoteConfig
+	-> M.Map Group PreferredContentExpression
+	-> UUID
+	-> (Matcher (MatchFiles Annex) -> Matcher (MatchFiles Annex))
+	-> (PreferredContentData -> [ParseToken (MatchFiles Annex)])
+	-> Either String (Matcher (MatchFiles Annex))
+	-> PreferredContentExpression
+	-> Either String (Matcher (MatchFiles Annex))
+makeMatcher groupmap configmap groupwantedmap u matcherf mktokens unknownmatcher = go True True
+  where
+	go expandstandard expandgroupwanted expr
+		| null (lefts tokens) = Right $ matcherf $ generate $ rights tokens
+		| otherwise = Left $ unwords $ lefts tokens
+	  where
+		tokens = preferredContentParser (mktokens pcd) expr
+		pcd = PCD
+			{ matchStandard = matchstandard
+			, matchGroupWanted = matchgroupwanted
+			, getGroupMap = pure groupmap
+			, configMap = configmap
+			, repoUUID = Just u
+			}
+		matchstandard
+			| expandstandard = maybe unknownmatcher (go False False)
+				(standardPreferredContent <$> getStandardGroup mygroups)
+			| otherwise = unknownmatcher
+		matchgroupwanted
+			| expandgroupwanted = maybe unknownmatcher (go True False)
+				(groupwanted mygroups)
+			| otherwise = unknownmatcher
+		mygroups = fromMaybe S.empty (u `M.lookup` groupsByUUID groupmap)
+		groupwanted s = case M.elems $ M.filterWithKey (\k _ -> S.member k s) groupwantedmap of
+			[pc] -> Just pc
+			_ -> Nothing
+
+{- Checks if an expression can be parsed, if not returns Just error -}
+checkPreferredContentExpression :: PreferredContentExpression -> Maybe String
+checkPreferredContentExpression expr = 
+	case parsedToMatcher (MatcherDesc mempty) tokens of
+		Left e -> Just e
+		Right _ -> Nothing
+  where
+	tokens = preferredContentParser (preferredContentTokens pcd) expr
+	pcd = PCD
+		{ matchStandard = Right matchAll
+		, matchGroupWanted = Right matchAll
+		, getGroupMap = pure emptyGroupMap
+		, configMap = M.empty
+		, repoUUID = Nothing
+		}