package main

import (
	"net/http"
	"strings"
)

func withCORS(next http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		origin := strings.TrimSpace(r.Header.Get("Origin"))

		// Dev-Origins erlauben
		if origin == "http://localhost:5173" || origin == "http://127.0.0.1:5173" {
			w.Header().Set("Access-Control-Allow-Origin", origin)
			w.Header().Set("Vary", "Origin")
			w.Header().Set("Access-Control-Allow-Methods", "GET,POST,DELETE,HEAD,OPTIONS")
			w.Header().Set("Access-Control-Allow-Headers", "Content-Type, Range, Last-Event-ID")
			w.Header().Set("Access-Control-Expose-Headers", "Content-Length, Content-Range, Accept-Ranges")
			// Nur wenn du wirklich Cookies/Authorization cross-origin brauchst:
			// w.Header().Set("Access-Control-Allow-Credentials", "true")
		}

		if r.Method == http.MethodOptions {
			w.WriteHeader(http.StatusNoContent)
			return
		}

		next.ServeHTTP(w, r)
	})
}