package middleware

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

	"github.com/konduktor/konduktor/internal/logging"
)

type responseWriter struct {
	http.ResponseWriter
	status int
	size   int
}

func (rw *responseWriter) WriteHeader(code int) {
	rw.status = code
	rw.ResponseWriter.WriteHeader(code)
}

func (rw *responseWriter) Write(b []byte) (int, error) {
	size, err := rw.ResponseWriter.Write(b)
	rw.size += size
	return size, err
}

func ServerHeader(next http.Handler, version string) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.Header().Set("Server", fmt.Sprintf("konduktor/%s", version))
		next.ServeHTTP(w, r)
	})
}

func AccessLog(next http.Handler, logger *logging.Logger) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		start := time.Now()

		wrapped := &responseWriter{
			ResponseWriter: w,
			status:         http.StatusOK,
		}

		next.ServeHTTP(wrapped, r)

		duration := time.Since(start)

		logger.Info("HTTP request",
			"method", r.Method,
			"path", r.URL.Path,
			"status", wrapped.status,
			"duration_ms", duration.Milliseconds(),
			"client_ip", r.RemoteAddr,
			"user_agent", r.UserAgent(),
		)
	})
}

func Recovery(next http.Handler, logger *logging.Logger) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		defer func() {
			if err := recover(); err != nil {
				logger.Error("Panic recovered",
					"error", fmt.Sprintf("%v", err),
					"stack", string(debug.Stack()),
				)
				http.Error(w, "Internal Server Error", http.StatusInternalServerError)
			}
		}()

		next.ServeHTTP(w, r)
	})
}