///////////////////////////////////////////////////////////////////////////////
//
//  Microsoft Research Singularity
//
//  Copyright (c) Microsoft Corporation.  All rights reserved.
//
//  File:   MapPointProxyContract.sg
//  Note:   Contract for a ChildMapPointProxy process
//

using System;
using Microsoft.SingSharp;
using Microsoft.Singularity.Channels;
using Microsoft.Singularity.Extending;

namespace Microsoft.Singularity.MapPointProxy.Contracts
{
    public contract MapPointProxyContract : ExtensionContract
    {
        public rep struct PushPin : ITracked
        {
            // Everything as character vectors; the coordinates
            // are floating-point
            public char[] in ExHeap latitude;
            public char[] in ExHeap longitude;
            public char[] in ExHeap icon;
            public char[] in ExHeap label;
        }

        public const string ModuleName = "/dev/MapPointProxy";

        in message GetMap(char[]! in ExHeap centerLat, char[]! in ExHeap centerLong,
                          int zoom, PushPin[] in ExHeap pushPins);
        in message Ack();

        out message MapPointReady();
        out message MapDataBegin();
        out message MapDataChunk(byte[]! in ExHeap chunkData);
        out message Done();
        out message Failed();

        override state Start : MapPointReady! -> ReadyState;

        state ReadyState : GetMap? -> MapResult;

        state MapResult : one
        {
            MapDataBegin! -> SendingState;
            Failed! -> ReadyState;
        }

        state SendingState : one
        {
            MapDataChunk! -> Ack? -> SendingState;
            Done! -> ReadyState;
        }
    }
}