/// <summary>
        /// Populates the view model from the data received from the request.
        /// </summary>
        /// <returns></returns>
        public void PopulateViewModel(RedwoodRequestContext context, RedwoodView view, string serializedPostData)
        {
            var viewModelConverter = new ViewModelJsonConverter();

            // get properties
            var data = context.ReceivedViewModelJson = JObject.Parse(serializedPostData);
            var viewModelToken = (JObject)data["viewModel"];

            // load CSRF token
            context.CsrfToken = viewModelToken["$csrfToken"].Value<string>();

            if (viewModelToken["$encryptedValues"] != null)
            {
                // load encrypted values
                var encryptedValuesString = viewModelToken["$encryptedValues"].Value<string>();
                viewModelConverter.EncryptedValues = JArray.Parse(viewModelProtector.Unprotect(encryptedValuesString, context));
            }
            else viewModelConverter.EncryptedValues = new JArray();

            // get validation path
            context.ModelState.ValidationTargetPath = data["validationTargetPath"].Value<string>();

            // populate the ViewModel
            var serializer = new JsonSerializer();
            serializer.Converters.Add(viewModelConverter);
            viewModelConverter.Populate(viewModelToken, serializer, context.ViewModel);

            // load the control state
            var walker = new ViewModelJTokenControlTreeWalker(viewModelToken, view);
            walker.ProcessControlTree(walker.LoadControlState);
        }
 /// <summary>
 /// Serializes the validation rules.
 /// </summary>
 private JObject SerializeValidationRules(ViewModelJsonConverter viewModelConverter)
 {
     var validationRules = new JObject();
     foreach (var map in viewModelConverter.UsedSerializationMaps)
     {
         var rule = new JObject();
         foreach (var property in map.Properties.Where(p => p.ClientValidationRules.Any()))
         {
             rule[property.Name] = JToken.FromObject(property.ClientValidationRules);
         }
         if (rule.Count > 0) validationRules[map.Type.ToString()] = rule;
     }
     return validationRules;
 }
        /// <summary>
        /// Builds the view model for the client.
        /// </summary>
        public void BuildViewModel(RedwoodRequestContext context, RedwoodView view)
        {
            // serialize the ViewModel
            var serializer = new JsonSerializer();
            var viewModelConverter = new ViewModelJsonConverter()
            {
                EncryptedValues = new JArray(),
                UsedSerializationMaps = new HashSet<ViewModelSerializationMap>()
            };
            serializer.Converters.Add(viewModelConverter);
            var writer = new JTokenWriter();
            serializer.Serialize(writer, context.ViewModel);

            // save the control state
            var walker = new ViewModelJTokenControlTreeWalker(writer.Token, view);
            walker.ProcessControlTree(walker.SaveControlState);

            // persist CSRF token
            writer.Token["$csrfToken"] = context.CsrfToken;

            // persist encrypted values
            if (viewModelConverter.EncryptedValues.Count > 0)
                writer.Token["$encryptedValues"] = viewModelProtector.Protect(viewModelConverter.EncryptedValues.ToString(Formatting.None), context);

            // serialize validation rules
            var validationRules = SerializeValidationRules(viewModelConverter);

            // create result object
            var result = new JObject();
            result["viewModel"] = writer.Token;
            result["url"] = context.OwinContext.Request.Uri.PathAndQuery;
            result["virtualDirectory"] = RedwoodMiddleware.GetVirtualDirectory(context.OwinContext);
            if (context.IsPostBack || context.IsSpaRequest)
            {
                result["action"] = "successfulCommand";

                result["resources"] = BuildResourcesJson(context, _ => true);
            }
            else
            {
                result["renderedResources"] = JArray.FromObject(context.ResourceManager.RequiredResources);
            }
            // TODO: do not send on postbacks
            if (validationRules.Count > 0) result["validationRules"] = validationRules;

            context.ViewModelJson = result;
        }