using System;
using System.Collections.Generic;
using System.Text;
using System.Net;
using System.IO;
using FastReport.Export;
using FastReport.Cloud.OAuth;
using FastReport.Utils;

namespace FastReport.Cloud.StorageClient.SkyDrive
{
    /// <summary>
    /// SkyDrive cloud storage client.
    /// </summary>
    public class SkyDriveStorageClient : CloudStorageClient
    {
        #region Fields

        private ClientInfo clientInfo;
        private string authCode;
        private string accessToken;

        #endregion // Fields

        #region Properties

        /// <summary>
        /// Gets or sets the client info.
        /// </summary>
        public ClientInfo ClientInfo
        {
            get { return clientInfo; }
            set { clientInfo = value; }
        }

        /// <summary>
        /// Gets or sets the authorization code.
        /// </summary>
        public string AuthCode
        {
            get { return authCode; }
            set { authCode = value; }
        }

        /// <summary>
        /// Gets or sets the access token.
        /// </summary>
        public string AccessToken
        {
            get { return accessToken; }
            set { accessToken = value; }
        }

        #endregion // Properties

        #region Constructors

        /// <summary>
        /// Initializes a new instance of the <see cref="SkyDriveStorageClient"/> class.
        /// </summary>
        public SkyDriveStorageClient() : base()
        {
            clientInfo = new ClientInfo("", "", "");
            authCode = "";
            accessToken = "";
        }

        /// <summary>
        /// Initializes a new instance of the <see cref="SkyDriveStorageClient"/> class.
        /// </summary>
        /// <param name="clientInfo">The client info.</param>
        public SkyDriveStorageClient(ClientInfo clientInfo) : base()
        {
            this.clientInfo = clientInfo;
            authCode = "";
            accessToken = "";
        }

        /// <summary>
        /// Initializes a new instance of the <see cref="SkyDriveStorageClient"/> class.
        /// </summary>
        /// <param name="clientId">Client ID.</param>
        /// <param name="clientSecret">Client Secret.</param>
        public SkyDriveStorageClient(string clientId, string clientSecret) : base()
        {
            this.clientInfo = new ClientInfo("", clientId, clientSecret);
            authCode = "";
            accessToken = "";
        }

        #endregion // Constructors

        #region Private Methods

        private byte[] BuildGetAccessTokenRequestContent()
        {
            Dictionary<string, string> data = new Dictionary<string, string>();
            data.Add("client_id", clientInfo.Id);
            data.Add("redirect_uri", @"https://login.microsoftonline.com/common/oauth2/nativeclient");
            data.Add("grant_type", "authorization_code");
            data.Add("code", authCode);
            return Encoding.UTF8.GetBytes(HttpUtils.UrlDataEncode(data));
        }

        #endregion // Private Methods

        #region Protected Methods

        /// <inheritdoc/>
        protected override void SaveMemoryStream(MemoryStream ms)
        {
            string url = String.Format(@"https://graph.microsoft.com/v1.0/me/drive/items/root:/{0}:/content", Filename);
            try
            {
                System.Net.ServicePointManager.SecurityProtocol = (SecurityProtocolType)(0xc0 | 0x300 | 0xc00);
                WebRequest request = WebRequest.Create(url);
                request.Method = HttpMethod.Put;
                RequestUtils.SetProxySettings(request, ProxySettings);
                request.Headers.Add("Authorization", $"Bearer {accessToken}");

                int length = Convert.ToInt32(ms.Length);
                byte[] buffer = new byte[length];
                ms.Read(buffer, 0, length);
                request.ContentLength = buffer.Length;
                request.ContentType = "application/octet-stream";
                using (Stream rs = request.GetRequestStream())
                {
                    rs.Write(buffer, 0, length);
                }

                WebResponse response = request.GetResponse();
                Stream stream = response.GetResponseStream();
            }
            catch (Exception ex)
            {
                throw new CloudStorageException(ex.Message, ex);
            }
        }

        #endregion // Protected Methods

        #region Public Methods

        /// <summary>
        /// Gets the authorization URL.
        /// </summary>
        /// <returns>The authorization URL string.</returns>
        public string GetAuthorizationUrl()
        {
            return String.Format($@"https://login.microsoftonline.com/common/oauth2/v2.0/authorize?response_type=code&client_id={clientInfo.Id}&scope=files.readwrite offline_access&redirect_uri=https://login.microsoftonline.com/common/oauth2/nativeclient");
        }

        /// <summary>
        /// Gets the access token.
        /// </summary>
        /// <returns>The access token value.</returns>
        public string GetAccessToken()
        {
            System.Net.ServicePointManager.SecurityProtocol = (SecurityProtocolType)(0xc0 | 0x300 | 0xc00);
            WebRequest request = WebRequest.Create(@"https://login.microsoftonline.com/common/oauth2/v2.0/token");
            request.Method = HttpMethod.Post;
            RequestUtils.SetProxySettings(request, ProxySettings);

            request.ContentType = "application/x-www-form-urlencoded";
            byte[] content = BuildGetAccessTokenRequestContent();
            request.ContentLength = content.Length;
            using (Stream rs = request.GetRequestStream())
            {
                rs.Write(content, 0, content.Length);
            }

            using (WebResponse response = request.GetResponse())
            {
                accessToken = Parser.ParseSkyDriveToken(response.GetResponseStream());
            }

            return accessToken;
        }

        #endregion // Public Methods
    }
}