using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Runtime.Serialization.Json;
using System.ServiceModel.Channels;
using System.ServiceModel.Dispatcher;
using System.Text;

namespace Taloyhtio.GeneralSSO.Server.CodeFiles.Infrastructure.WCF
{
    // See http://stackoverflow.com/questions/1149037/how-to-make-custom-wcf-error-handler-return-json-response-with-non-ok-http-code
    public class JsonErrorHandler : IErrorHandler
    {
        public bool HandleError(Exception error)
        {
            // yes, we handled this exception
            return true;
        }

        public void ProvideFault(Exception error, MessageVersion version, ref Message fault)
        {
            // create message
            var jsonError = new JsonErrorDetails { Message = error.Message, ExceptionType = error.GetType().FullName };
            fault = Message.CreateMessage(version, "", jsonError, new DataContractJsonSerializer(typeof(JsonErrorDetails)));

            // tell WCF to use JSON encoding rather than default XML
            var wbf = new WebBodyFormatMessageProperty(WebContentFormat.Json);
            fault.Properties.Add(WebBodyFormatMessageProperty.Name, wbf);

            // modify response
            var rmp = new HttpResponseMessageProperty
            {
                StatusCode = HttpStatusCode.InternalServerError,
                StatusDescription = "Internal server error",
            };
            rmp.Headers[HttpResponseHeader.ContentType] = "application/json";
            fault.Properties.Add(HttpResponseMessageProperty.Name, rmp);
        }
    }
}