using FluentValidation;

namespace WebApi.Filters;

public sealed class ValidationFilter : IEndpointFilter
{
    public async ValueTask<object?> InvokeAsync(EndpointFilterInvocationContext context, EndpointFilterDelegate next)
    {
        foreach (var argument in context.Arguments)
        {
            if (argument is null)
                continue;

            var validatorType = typeof(IValidator<>).MakeGenericType(argument.GetType());

            if (context.HttpContext.RequestServices.GetService(validatorType) is not IValidator validator)
                continue;

            var validationContext = new ValidationContext<object>(argument);
            var result = await validator.ValidateAsync(validationContext, context.HttpContext.RequestAborted);

            if (!result.IsValid)
                return Results.ValidationProblem(result.ToDictionary());
        }

        return await next(context);
    }
}