package middleware

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

// Logger is structured request-logging middleware using log/slog.
// It records method, path, status code, and response duration for every request.
func Logger(next http.Handler) 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)
		slog.Info("request",
			"method", r.Method,
			"path", r.URL.Path,
			"status", wrapped.status,
			"duration_ms", time.Since(start).Milliseconds(),
		)
	})
}

// responseWriter wraps http.ResponseWriter to capture the status code.
type responseWriter struct {
	http.ResponseWriter
	status int
}

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