package mw

import (
	"net/http"
	"runtime/debug"

	"code.nochebuena.dev/einherjar/contracts/logging"
)

// Recover catches panics in downstream handlers, writes a 500 response, and
// logs the recovered value with a stack trace. Place it as the outermost middleware.
func Recover(logger logging.Logger) func(http.Handler) http.Handler {
	return func(next http.Handler) http.Handler {
		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
			defer func() {
				if rec := recover(); rec != nil {
					logger.WithContext(r.Context()).Error("recover: panic", nil,
						"panic", rec,
						"stack", string(debug.Stack()),
					)
					http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
				}
			}()
			next.ServeHTTP(w, r)
		})
	}
}