/// <summary>
/// Executes content negotiation on current <see cref="HttpResponse"/>, utilizing an accepted media type if possible and defaulting to "application/json" if none found.
/// </summary>
/// <param name="response">Current <see cref="HttpResponse"/></param>
/// <param name="obj">View model</param>
/// <param name="cancellationToken"><see cref="CancellationToken"/></param>
/// <returns><see cref="Task"/></returns>
public static async Task Negotiate(this HttpResponse response, object obj, CancellationToken cancellationToken = default)
{
var negotiators = response.HttpContext.RequestServices.GetServices <IResponseNegotiator>();
IResponseNegotiator negotiator = null;
MediaTypeHeaderValue.TryParseList(response.HttpContext.Request.Headers["Accept"], out var accept);
if (accept != null)
{
var ordered = accept.OrderByDescending(x => x.Quality ?? 1);
foreach (var acceptHeader in ordered)
{
negotiator = negotiators.FirstOrDefault(x => x.CanHandle(acceptHeader));
if (negotiator != null)
{
break;
}
}
}
if (negotiator == null)
{
negotiator = negotiators.FirstOrDefault(x => x.CanHandle(new MediaTypeHeaderValue("application/json")));
}
await negotiator.Handle(response.HttpContext.Request, response, obj, cancellationToken);
}
