// 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.Collections.Generic;
using System.Net;
using System.Net.Http;
using System.Net.WebSockets;
using System.Security.Cryptography.X509Certificates;
using System.Threading.Tasks;

namespace Microsoft.AspNetCore.Http.Connections.Client
{
    /// <summary>
    /// Options used to configure a <see cref="HttpConnection"/> instance.
    /// </summary>
    public class HttpConnectionOptions
    {
        private IDictionary<string, string> _headers;
        private X509CertificateCollection _clientCertificates;
        private CookieContainer _cookies;

        /// <summary>
        /// Initializes a new instance of the <see cref="HttpConnectionOptions"/> class.
        /// </summary>
        public HttpConnectionOptions()
        {
            _headers = new Dictionary<string, string>();
            _clientCertificates = new X509CertificateCollection();
            _cookies = new CookieContainer();

            Transports = HttpTransports.All;
        }

        /// <summary>
        /// Gets or sets a delegate for wrapping or replacing the <see cref="HttpMessageHandlerFactory"/>
        /// that will make HTTP requests.
        /// </summary>
        public Func<HttpMessageHandler, HttpMessageHandler> HttpMessageHandlerFactory { get; set; }

        /// <summary>
        /// Gets or sets a collection of headers that will be sent with HTTP requests.
        /// </summary>
        public IDictionary<string, string> Headers
        {
            get => _headers;
            set => _headers = value ?? throw new ArgumentNullException(nameof(value));
        }

        /// <summary>
        /// Gets or sets a collection of client certificates that will be sent with HTTP requests.
        /// </summary>
        public X509CertificateCollection ClientCertificates
        {
            get => _clientCertificates;
            set => _clientCertificates = value ?? throw new ArgumentNullException(nameof(value));
        }

        /// <summary>
        /// Gets or sets a collection of cookies that will be sent with HTTP requests.
        /// </summary>
        public CookieContainer Cookies
        {
            get => _cookies;
            set => _cookies = value ?? throw new ArgumentNullException(nameof(value));
        }

        /// <summary>
        /// Gets or sets the URL used to send HTTP requests.
        /// </summary>
        public Uri Url { get; set; }

        /// <summary>
        /// Gets or sets a bitmask comprised of one or more <see cref="HttpTransportType"/> that specify what transports the client should use to send HTTP requests.
        /// </summary>
        public HttpTransportType Transports { get; set; }

        /// <summary>
        /// Gets or sets a value indicating whether negotiation is skipped when connecting to the server.
        /// </summary>
        /// <remarks>
        /// Negotiation can only be skipped when using the <see cref="HttpTransportType.WebSockets"/> transport.
        /// </remarks>
        public bool SkipNegotiation { get; set; }

        /// <summary>
        /// Gets or sets an access token provider that will be called to return a token for each HTTP request.
        /// </summary>
        public Func<Task<string>> AccessTokenProvider { get; set; }

        /// <summary>
        /// Gets or sets a close timeout.
        /// </summary>
        public TimeSpan CloseTimeout { get; set; } = TimeSpan.FromSeconds(5);

        /// <summary>
        /// Gets or sets the credentials used when making HTTP requests.
        /// </summary>
        public ICredentials Credentials { get; set; }

        /// <summary>
        /// Gets or sets the proxy used when making HTTP requests.
        /// </summary>
        public IWebProxy Proxy { get; set; }

        /// <summary>
        /// Gets or sets a value indicating whether default credentials are used when making HTTP requests.
        /// </summary>
        public bool? UseDefaultCredentials { get; set; }

        /// <summary>
        /// Gets or sets a delegate that will be invoked with the <see cref="ClientWebSocketOptions"/> object used
        /// to configure the WebSocket when using the WebSockets transport.
        /// </summary>
        /// <remarks>
        /// This delegate is invoked after headers from <see cref="Headers"/> and the access token from <see cref="AccessTokenProvider"/>
        /// has been applied.
        /// </remarks>
        public Action<ClientWebSocketOptions> WebSocketConfiguration { get; set; }
    }
}