using System;
using System.Net;
using System.Text;

using RestSharp;

namespace RestSharpExtensions
{
  internal static class RestSharpExtensions
  {
    public static bool IsSuccessStatusCode(this HttpStatusCode responseCode)
    {
      var numericResponse = (int)responseCode;

      const int statusCodeOk = (int)HttpStatusCode.OK;

      const int statusCodeBadRequest = (int)HttpStatusCode.BadRequest;

      return numericResponse >= statusCodeOk &&
             numericResponse < statusCodeBadRequest;
    }

    public static bool IsSuccessful(this IRestResponse response)
    {
      return response.StatusCode.IsScuccessStatusCode() &&
             response.ResponseStatus == ResponseStatus.Completed;
    }

    public static void EnsureResponseWasSuccessful(this IRestClient client, IRestRequest request, IRestResponse response)
    {
      if (response.IsSuccessful())
      {
        return;
      }

      var requestUri = client.BuildUri(request);

      throw RestException.CreateException(requestUri, response);
    }
  }

  public class RestException : Exception
  {
    public RestException(HttpStatusCode httpStatusCode, Uri requestUri, string content, string message, Exception innerException)
      : base(message, innerException)
    {
      HttpStatusCode = httpStatusCode;
      RequestUri = requestUri;
      Content = content;
    }

    public HttpStatusCode HttpStatusCode { get; private set; }

    public Uri RequestUri { get; private set; }

    public string Content { get; private set; }

    public static RestException CreateException(Uri requestUri, IRestResponse response)
    {
      Exception innerException = null;

      var messageBuilder = new StringBuilder();

      messageBuilder.AppendLine(string.Format("Processing request [{0}] resulted with following errors:", requestUri));

      if (response.StatusCode.IsScuccessStatusCode() == false)
      {
        messageBuilder.AppendLine("- Server responded with unsuccessfult status code: " + response.StatusDescription);
      }

      if (response.ErrorException != null)
      {
        messageBuilder.AppendLine("- An exception occurred while processing request: " + response.ErrorMessage);

        innerException = response.ErrorException;
      }

      return new RestException(response.StatusCode, requestUri, response.Content, messageBuilder.ToString(), innerException);
    }
  }
}