using System.Linq;
using Swashbuckle.AspNetCore.Swagger;
using Swashbuckle.AspNetCore.SwaggerGen;

namespace Infrastructure.Web.Mvc.Swagger.Filters
{
    public class SwaggerDefaultValues : IOperationFilter
    {
        public void Apply(Operation operation, OperationFilterContext context)
        {
            if (operation.Parameters == null) return;

            foreach (var parameter in operation.Parameters.OfType<NonBodyParameter>())
            {
                var description = context.ApiDescription
                    .ParameterDescriptions
                    .First(p => p.Name == parameter.Name);
                var routeInfo = description.RouteInfo;

                if (parameter.Description == null) parameter.Description = description.ModelMetadata?.Description;

                if (routeInfo == null) continue;

                if (parameter.Default == null) parameter.Default = routeInfo.DefaultValue;

                parameter.Required |= !routeInfo.IsOptional;
            }
        }
    }
}