package middlewares

import (
	"net/http"

	"gitea.konchin.com/go2025/backend/utils"
	"github.com/uptrace/bunrouter"
	"go.opentelemetry.io/otel/attribute"
	semconv "go.opentelemetry.io/otel/semconv/v1.17.0"
	"go.opentelemetry.io/otel/trace"
)

func BunrouterOtel(next bunrouter.HandlerFunc) bunrouter.HandlerFunc {
	return func(w http.ResponseWriter, req bunrouter.Request) error {
		span := trace.SpanFromContext(req.Context())
		if !span.IsRecording() {
			return next(w, req)
		}

		params := req.Params()
		span.SetName(req.Method + " " + params.Route())

		paramSlice := params.Slice()
		attrs := make([]attribute.KeyValue, 0, 3+len(paramSlice))

		attrs = append(attrs, semconv.HTTPRouteKey.String(req.Route()))

		if req.URL != nil {
			attrs = append(attrs, semconv.HTTPTargetKey.String(req.URL.RequestURI()))
		} else {
			// This should never occur if the request was generated by the net/http
			// package. Fail gracefully, if it does though.
			attrs = append(attrs, semconv.HTTPTargetKey.String(req.RequestURI))
		}

		attrs = append(attrs, semconv.HTTPClientIPKey.String(
			utils.GetRemoteAddr(req)))

		for _, param := range paramSlice {
			attrs = append(attrs, attribute.String("http.route.param."+param.Key,
				param.Value))
		}

		span.SetAttributes(attrs...)

		return next(w, req)
	}
}