using System;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Mvc.ModelBinding;

namespace RdtClient.Service.Helpers
{
    public class JsonModelBinder : IModelBinder
    {
        public Task BindModelAsync(ModelBindingContext bindingContext)
        {
            if (bindingContext == null)
            {
                throw new ArgumentNullException(nameof(bindingContext));
            }

            var valueProviderResult = bindingContext.ValueProvider.GetValue(bindingContext.ModelName);
            if (valueProviderResult != ValueProviderResult.None)
            {
                bindingContext.ModelState.SetModelValue(bindingContext.ModelName, valueProviderResult);

                var valueAsString = valueProviderResult.FirstValue;
                var result = Newtonsoft.Json.JsonConvert.DeserializeObject(valueAsString, bindingContext.ModelType);
                if (result != null)
                {
                    bindingContext.Result = ModelBindingResult.Success(result);
                    return Task.CompletedTask;
                }
            }

            return Task.CompletedTask;
        }
    }
}