#region Copyright notice and license

// Copyright 2015 gRPC authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#endregion

using System;
using System.Collections.Generic;
using System.Threading.Tasks;

using Grpc.Core.Internal;
using Grpc.Core.Utils;

namespace Grpc.Core
{
    /// <summary>
    /// Asynchronous authentication interceptor for <see cref="CallCredentials"/>.
    /// </summary>
    /// <param name="context">The interceptor context.</param>
    /// <param name="metadata">Metadata to populate with entries that will be added to outgoing call's headers.</param>
    /// <returns></returns>
    public delegate Task AsyncAuthInterceptor(AuthInterceptorContext context, Metadata metadata);

    /// <summary>
    /// Context for an RPC being intercepted by <see cref="AsyncAuthInterceptor"/>.
    /// </summary>
    public class AuthInterceptorContext
    {
        readonly string serviceUrl;
        readonly string methodName;

        /// <summary>
        /// Initializes a new instance of <c>AuthInterceptorContext</c>.
        /// </summary>
        public AuthInterceptorContext(string serviceUrl, string methodName)
        {
            this.serviceUrl = GrpcPreconditions.CheckNotNull(serviceUrl);
            this.methodName = GrpcPreconditions.CheckNotNull(methodName);
        }

        /// <summary>
        /// The fully qualified service URL for the RPC being called.
        /// </summary>
        public string ServiceUrl
        {
            get { return serviceUrl; }
        }

        /// <summary>
        /// The method name of the RPC being called.
        /// </summary>
        public string MethodName
        {
            get { return methodName; }
        }
    }
}