////////////////////////////////////////////////////////////////////////////////
//
//  Microsoft Research Singularity
//
//  Copyright (c) Microsoft Corporation.  All rights reserved.
//
//  File:   DirectoryServiceContract.sg
//

using Microsoft.SingSharp;
using Microsoft.Singularity.Channels;

namespace Microsoft.Singularity.Directory
{
    public enum NodeType
    {
        Inner       = 0,
        Dir         = 1,
        Provider    = 2,
        SymLink     = 3,
        File        = 4,
        IoMemory    = 5,
    }

    public rep struct FindResponse : ITracked
    {
        public char[]! in ExHeap Path;
        public NodeType Type;
    }

    public contract DirectoryServiceContract : ServiceContract
    {
        // ReadOnly part

        in     message Bind(char[]! in ExHeap path, ServiceContract.Exp:Start! exp);
        out    message AckBind();
        out    message NakBind(ServiceContract.Exp:Start exp); // return unconnected endpoint

        in     message Notify(char[]! in ExHeap pathSpec, NotifyContract.Imp:Start! imp);
        out    message AckNotify();
        out    message NakNotify(NotifyContract.Imp:Start! imp); // return unconnected endpoint

        in     message Find(char[]! in ExHeap pathSpec, char[]! in ExHeap pattern);
        out    message AckFind(FindResponse[]! in ExHeap results);
        out    message NakFind();

        out message Success();

        override state Start: one {
            Success! -> Ready;
        }
        state Ready: one
        {
            Bind? ->    ( AckBind! or NakBind!  ) -> Ready;
            Find? ->    ( AckFind! or NakFind!  ) -> Ready;
            Notify? ->  ( AckNotify! or NakNotify! ) -> Ready;
       }
   }
}