// Copyright (c) .NET Foundation. All rights reserved.
// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.

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

namespace Microsoft.AspNetCore.Http.Connections.Client.Internal
{
    internal class AccessTokenHttpMessageHandler : DelegatingHandler
    {
        private readonly HttpConnection _httpConnection;

        public AccessTokenHttpMessageHandler(HttpMessageHandler inner, HttpConnection httpConnection) : base(inner)
        {
            _httpConnection = httpConnection;
        }

        protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
        {
            var accessToken = await _httpConnection.GetAccessTokenAsync();

            if (!string.IsNullOrEmpty(accessToken))
            {
                request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", accessToken);
            }

            return await base.SendAsync(request, cancellationToken);
        }
    }
}