using System;
using System.IO;
using System.Net;
using System.Text;
using System.Collections.Generic;

namespace Endpoint
{
	/// <summary>
	/// Http Endpoint - such as a webserver, a webservice, etc
	/// </summary>
	[Serializable]
	public class HttpEndpoint : IServiceEndpoint
	{
		/// <summary>
		/// Returns the response string grabbed from the passed in URL.
		/// </summary>
		/// <param name="url">The URL.</param>
		/// <param name="contentType">The HTTP contentType.</param>
		/// <param name="requestContent">The request content.</param>
		/// <param name="webHeaders">The web headers.</param>
		/// <returns>A string containing response</returns>
		protected static string GetUrlContent(Uri url, string contentType, string requestContent, Dictionary<string,string> webHeaders)
		{
			// POST request
			if (!string.IsNullOrEmpty(contentType) && !string.IsNullOrEmpty(requestContent))
			{
				HttpWebRequest webRequest = (HttpWebRequest)WebRequest.Create(url);

				// NOTE: proxy?
				// webRequest.Proxy = new WebProxy();

				// SOAP
				webRequest.ContentType = contentType;
				if (webHeaders != null && webHeaders.Count > 0)
					foreach (KeyValuePair<string, string> webHeader in webHeaders)
						webRequest.Headers.Add(webHeader.Key, webHeader.Value);
					

				// NOTE: SOAPACtion
				//webRequest.Headers.Add("SOAPAction", "\"urn:getPaymentKey\"");

				// FORM
				//webRequest.ContentType = "application/x-www-form-urlencoded";

				webRequest.Method = "POST";
				// webRequest.Accept = "text/xml";

				//We need to count how many bytes we're sending. Post'ed Faked Forms should be name=value&
				byte[] bytes = Encoding.ASCII.GetBytes(requestContent);
				webRequest.ContentLength = bytes.Length;
				using (Stream requestStream = webRequest.GetRequestStream())
				{
					requestStream.Write(bytes, 0, bytes.Length); //write it to the stream
				}
				WebResponse webResponse = webRequest.GetResponse();
				if (webResponse == null)
					return null;
				using (var streamReader = new StreamReader(webResponse.GetResponseStream()))
				{
					return streamReader.ReadToEnd();
				}
			}

			// GET Request
			var client = new WebClient();
			using (Stream data = client.OpenRead(url))
			using (var reader = new StreamReader(data))
			{
				return reader.ReadToEnd();
			}
		}

		protected readonly IHttpEndpointConfiguration _httpEndpointConfiguration;
		
		/// <summary>
		/// Returns a string explaining details on the current status
		/// </summary>
		/// <returns>string with status message</returns>
		public virtual string StatusDescription
		{
			get; protected set;
		}

		public IServiceEndpointConfiguration ServiceEndpointConfiguration
		{
			get { return _httpEndpointConfiguration; }
		}

		/// <summary>
		/// Gets the service name
		/// </summary>
		/// <value></value>
		public string ServiceName
		{
			get { return _httpEndpointConfiguration.Name; }
		}

		/// <summary>
		/// Gets the HTTP endpoint configuration.
		/// </summary>
		/// <value>The HTTP endpoint configuration.</value>
		public IHttpEndpointConfiguration HttpEndpointConfiguration
		{
			get { return _httpEndpointConfiguration; }
		}

		/// <summary>
		/// Gets the current status result of the endpoint
		/// </summary>
		/// <returns>Status</returns>
		public virtual Status GetStatus()
		{
			try
			{
				WebRequest request = WebRequest.Create(HttpEndpointConfiguration.Uri);

				using (HttpWebResponse response = (HttpWebResponse)request.GetResponse())
				{
					StatusDescription = response.StatusDescription;
					if (response.StatusCode == HttpStatusCode.OK)
						return Status.Up;
					return Status.Unreachable;
				}
			}
			catch (WebException ex)
			{
				StatusDescription = ex.Message + " (" + ex.Status + ")";
				
				// TODO: LOG
				if (ex.Status == WebExceptionStatus.Timeout)
				{
					return Status.Timeout;
				}
				return Status.Unreachable;
			}
		}

		/// <summary>
		/// Initializes a new instance of the <see cref="HttpEndpoint"/> class.
		/// </summary>
		/// <param name="config">The HttpEndpointConfiguration.</param>
		public HttpEndpoint(IHttpEndpointConfiguration config)
		{
			_httpEndpointConfiguration = config;
		}
	}
}