RhSolutions-Api/RhSolutions.Api/Middleware/QueryModifier.cs

using Microsoft.AspNetCore.Http.Extensions;
using RhSolutions.Api.Services;

namespace RhSolutions.Api.Middleware;

public class QueryModifier
{
    private RequestDelegate _next;

    public QueryModifier(RequestDelegate nextDelegate)
    {
        _next = nextDelegate;
    }

    public async Task Invoke(HttpContext context, IProductTypePredicter typePredicter, ProductQueryModifierFactory productQueryModifierFactory)
    {
        if (context.Request.Method == HttpMethods.Get
                && context.Request.Path == "/api/search")
        {
            string query = context.Request.Query["query"].ToString();
            var productType = typePredicter.GetPredictedProductType(query);
            var modifier = productQueryModifierFactory.GetModifier(productType!);
            if (modifier.TryQueryModify(context.Request.Query, out var newQuery))
            {
                context.Request.QueryString = newQuery;
            }
        }
        await _next(context);
    }
}