//******************************************************************************************************
//  IHostedHttpHandler.cs - Gbtc
//
//  Copyright © 2016, Grid Protection Alliance.  All Rights Reserved.
//
//  Licensed to the Grid Protection Alliance (GPA) under one or more contributor license agreements. See
//  the NOTICE file distributed with this work for additional information regarding copyright ownership.
//  The GPA licenses this file to you under the MIT License (MIT), the "License"; you may not use this
//  file except in compliance with the License. You may obtain a copy of the License at:
//
//      http://opensource.org/licenses/MIT
//
//  Unless agreed to in writing, the subject software distributed under the License is distributed on an
//  "AS-IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. Refer to the
//  License for the specific language governing permissions and limitations.
//
//  Code Modification History:
//  ----------------------------------------------------------------------------------------------------
//  07/28/2016 - J. Ritchie Carroll
//       Generated original version of source code.
//
//******************************************************************************************************

using System.Net.Http;
using System.Threading;
using System.Threading.Tasks;

namespace GSF.Web.Hosting
{
    /// <summary>
    /// Defines an HTTP handler for self-hosted <see cref="WebServer"/> instances.
    /// </summary>
    public interface IHostedHttpHandler
    {
        /// <summary>
        /// Enables processing of HTTP web requests by a custom handler that implements the <see cref="IHostedHttpHandler"/> interface.
        /// </summary>
        /// <param name="request">HTTP request message.</param>
        /// <param name="response">HTTP response message.</param>
        /// <param name="cancellationToken">Propagates notification from client that operations should be canceled.</param>
        Task ProcessRequestAsync(HttpRequestMessage request, HttpResponseMessage response, CancellationToken cancellationToken);

        /// <summary>
        /// Determines if client cache should be enabled for rendered handler content.
        /// </summary>
        /// <remarks>
        /// If rendered handler content does not change often, the server and client will use the
        /// <see cref="GetContentHash"/> to determine if the client needs to refresh the content.
        /// </remarks>
        bool UseClientCache { get;  }

        /// <summary>
        /// Gets hash of response content based on any <paramref name="request"/> parameters.
        /// </summary>
        /// <param name="request">HTTP request message.</param>
        /// <remarks>
        /// Value is only used when <see cref="UseClientCache"/> is <c>true</c>.
        /// </remarks>
        long GetContentHash(HttpRequestMessage request);
    }
}