diff --git a/src/main/scala/servlet/BasicAuthenticationFilter.scala b/src/main/scala/servlet/BasicAuthenticationFilter.scala
index 203c518..d849845 100644
--- a/src/main/scala/servlet/BasicAuthenticationFilter.scala
+++ b/src/main/scala/servlet/BasicAuthenticationFilter.scala
@@ -54,15 +54,9 @@
   }
 
   private def isWritableUser(username: String, password: String, repository: RepositoryService.RepositoryInfo): Boolean = {
-    getAccountByUserName(username) match {
-      case Some(account) if(account.password == encrypt(password)) => {
-        // TODO Use hasWritePermission?
-        (account.isAdmin // administrator
-          || account.userName == repository.owner // repository owner
-          || getCollaborators(repository.owner, repository.name).contains(account.userName)) // collaborator
-      }
-      case _ => false
-    }
+    getAccountByUserName(username).map { account =>
+      account.password == encrypt(password) && hasWritePermission(repository.owner, repository.name, Some(account))
+    } getOrElse false
   }
   
   private def requireAuth(response: HttpServletResponse): Unit = {