//
//  PostJson.cs
//
//  Author:
//       Paul Schneider <paulschneider@free.fr>
//
//  Copyright (c) 2015 Paul Schneider
//
//  This program is free software: you can redistribute it and/or modify
//  it under the terms of the GNU Lesser General Public License as published by
//  the Free Software Foundation, either version 3 of the License, or
//  (at your option) any later version.
//
//  This program is distributed in the hope that it will be useful,
//  but WITHOUT ANY WARRANTY; without even the implied warranty of
//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//  GNU Lesser General Public License for more details.
//
//  You should have received a copy of the GNU Lesser General Public License
//  along with this program.  If not, see <http://www.gnu.org/licenses/>.
using System.Net;
using System.IO;
using System.Threading.Tasks;
using Newtonsoft.Json;
using System;

namespace Yavsc.Server.Helpers
{
    /// <summary>
    /// Simple json post method.
    /// </summary>
    public class SimpleJsonPostMethod : IDisposable
	{
    private HttpWebRequest request=null;

		/// <summary>
		/// Initializes a new instance of the Yavsc.Helpers.SimpleJsonPostMethod class.
		/// </summary>
		/// <param name="pathToMethod">Path to method.</param>
		public SimpleJsonPostMethod (string pathToMethod, string authorizationHeader = null, string method = "POST")
		{
			request = (HttpWebRequest) WebRequest.Create (pathToMethod);
			request.Method = method;
			request.Accept = "application/json";
			request.ContentType = "application/json";
			request.SendChunked = true;
			request.TransferEncoding = "UTF-8";
            if (authorizationHeader!=null)
                request.Headers["Authorization"]=authorizationHeader;
		}

        public void Dispose()
        {
            request.Abort();
        }

        /// <summary>
        /// Invoke the specified query.
        /// </summary>
        /// <param name="query">Query.</param>
        public async Task<TAnswer> Invoke<TAnswer>(object query)
		{

			using (Stream streamQuery = await request.GetRequestStreamAsync()) {
				using (StreamWriter writer = new StreamWriter(streamQuery)) {
					writer.Write (JsonConvert.SerializeObject(query));
				}}
			TAnswer ans = default (TAnswer);
			using (WebResponse response = await request.GetResponseAsync ()) {
				using (Stream responseStream =  response.GetResponseStream ()) {
					using (StreamReader rdr = new StreamReader (responseStream)) {
						ans = (TAnswer) JsonConvert.DeserializeObject<TAnswer> (rdr.ReadToEnd ());
					}
				}
				response.Close();
			}
			return ans;
		}
		
	}
}