package public

import (
	"net/http"
	"time"

	sresponse "git.sendico.io/tech/sxchnge/product/auth/response"
	"github.com/go-chi/chi/v5/middleware"
	"github.com/prometheus/client_golang/prometheus"
	"github.com/prometheus/client_golang/prometheus/promauto"
)

var flowRequests = promauto.NewCounterVec(prometheus.CounterOpts{Name: "sxchnge_auth_flow_requests_total", Help: "Authentication flow outcomes; success means this HTTP step completed, not email delivery."}, []string{"operation", "outcome"})
var flowDuration = promauto.NewHistogramVec(prometheus.HistogramOpts{Name: "sxchnge_auth_flow_duration_seconds", Help: "Authentication HTTP step latency."}, []string{"operation"})

func measured(operation string, handler sresponse.HandlerFunc) sresponse.HandlerFunc {
	return func(r *http.Request) http.HandlerFunc {
		start := time.Now()
		response := handler(r)
		return func(w http.ResponseWriter, r *http.Request) {
			wrapped := middleware.NewWrapResponseWriter(w, r.ProtoMajor)
			response(wrapped, r)
			outcome := "accepted"
			if wrapped.Status() >= 500 {
				outcome = "unavailable"
			} else if wrapped.Status() == 429 {
				outcome = "limited"
			} else if wrapped.Status() >= 400 {
				outcome = "rejected"
			}
			flowRequests.WithLabelValues(operation, outcome).Inc()
			flowDuration.WithLabelValues(operation).Observe(time.Since(start).Seconds())
		}
	}
}