package http

import (
	"log/slog"
	"net/http"
	"time"

	"github.com/go-chi/chi/v5/middleware"
)

// requestLogger logs each request once it completes, including method, path,
// status, byte count, duration, and the chi request id.
func requestLogger(log *slog.Logger) func(http.Handler) http.Handler {
	return func(next http.Handler) http.Handler {
		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
			ww := middleware.NewWrapResponseWriter(w, r.ProtoMajor)
			start := time.Now()

			defer func() {
				log.Info("http request",
					"method", r.Method,
					"path", r.URL.Path,
					"status", ww.Status(),
					"bytes", ww.BytesWritten(),
					"duration_ms", time.Since(start).Milliseconds(),
					"request_id", middleware.GetReqID(r.Context()),
				)
			}()

			next.ServeHTTP(ww, r)
		})
	}
}

// limitRequestBody caps every request body at maxBytes (http.MaxBytesReader),
// so a client cannot stream an unbounded upload to memory or to the temporary
// files multipart parsing spills to. A non-positive maxBytes disables the cap.
// JSON endpoints apply their own, smaller cap in httputil.DecodeJSON.
func limitRequestBody(maxBytes int64) func(http.Handler) http.Handler {
	return func(next http.Handler) http.Handler {
		if maxBytes <= 0 {
			return next
		}
		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
			r.Body = http.MaxBytesReader(w, r.Body, maxBytes)
			next.ServeHTTP(w, r)
		})
	}
}

// securityHeaders sets response headers that are safe for every route.
// nosniff stops browsers from MIME-sniffing user-supplied content (downloads,
// GeoJSON) into an executable type.
func securityHeaders(next http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.Header().Set("X-Content-Type-Options", "nosniff")
		next.ServeHTTP(w, r)
	})
}