Refactored "SQLMappingFunction"

*This commit is related to issue #529 [1]*

[1] #529

data/src/main/java/org/cryptomator/data/db/SQLiteCacheControl.kt

@@ -12,9 +12,13 @@ object SQLiteCacheControl {
 		private val newIdentifier: String
 			get() = UUID.randomUUID().toString()
 
-		override fun invoke(sql: String): String {
+		override fun map(sql: String): String {
 			return "$sql -- $newIdentifier"
 		}
+
+		override fun mapWhereClause(whereClause: String?): String {
+			return map(whereClause ?: "1 = 1")
+		}
 	}
 
 	fun SupportSQLiteOpenHelper.Factory.asCacheControlled(): SupportSQLiteOpenHelper.Factory = asMapped(RandomUUIDMapping)

data/src/main/java/org/cryptomator/data/db/sqlmapping/MappingSupportSQLiteDatabase.kt

@@ -72,18 +72,18 @@ internal class MappingSupportSQLiteDatabase(
 	private val helper = AOP_SQLiteDatabase()
 
 	private fun map(sql: String): String {
-		return mappingFunction(sql)
+		return mappingFunction.map(sql)
 	}
 
 	private fun map(query: SupportSQLiteQuery): SupportSQLiteQuery {
 		return MappingSupportSQLiteQuery(query)
 	}
 
-	private fun mapWhereClause(whereClause: String?): String {
+	private fun mapWhereClause(whereClause: String?): String? {
 		if (whereClause != null && whereClause.isBlank()) {
 			throw IllegalArgumentException()
 		}
-		return map(whereClause ?: "1 = 1")
+		return mappingFunction.mapWhereClause(whereClause)
 	}
 
 	private inner class MappingSupportSQLiteStatement(
@@ -188,4 +188,10 @@ fun SupportSQLiteOpenHelper.Factory.asMapped(mappingFunction: SQLMappingFunction
 	return MappingSupportSQLiteOpenHelperFactory(this, mappingFunction)
 }
 
-interface SQLMappingFunction : (String) -> String
+interface SQLMappingFunction {
+
+	fun map(sql: String): String
+
+	fun mapWhereClause(whereClause: String?): String?
+
+}