// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
 
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.Filters;
using Microsoft.AspNetCore.Mvc.Formatters;
using Microsoft.Extensions.Options;
 
namespace XmlFormattersWebSite;
 
[SetupOutputFormatters]
public class XmlDataContractApiController : XmlApiControllerBase
{
    private class SetupOutputFormattersAttribute : ResultFilterAttribute
    {
        public override void OnResultExecuting(ResultExecutingContext context)
        {
            if (!(context.Result is ObjectResult objectResult))
            {
                return;
            }
 
            // Both kinds of Xml serializers are configured for this application and use custom content-types to do formatter
            // selection. The globally configured formatters rely on custom content-type to perform conneg which does not play
            // well the ProblemDetails returning filters that defaults to using application/xml. We'll explicitly select the formatter for this controller.
            var mvcOptions = context.HttpContext.RequestServices.GetRequiredService<IOptions<MvcOptions>>();
            var xmlFormatter = mvcOptions.Value.OutputFormatters.OfType<XmlDataContractSerializerOutputFormatter>().First();
 
            objectResult.Formatters.Add(xmlFormatter);
        }
    }
}