package server

import (
	"net/http"
	"strings"
)

func applyCORSHeaders(w http.ResponseWriter, r *http.Request, allowedOrigins []string) {
	origin := strings.TrimSpace(r.Header.Get("Origin"))
	if origin == "" || len(allowedOrigins) == 0 {
		return
	}
	for _, allowed := range allowedOrigins {
		if strings.TrimSpace(allowed) == origin {
			w.Header().Set("Access-Control-Allow-Origin", origin)
			w.Header().Set("Vary", "Origin")
			return
		}
	}
}

func (s *Server) writeCORS(w http.ResponseWriter, r *http.Request) {
	if s.cfg == nil {
		return
	}
	applyCORSHeaders(w, r, s.cfg.CORSAllowedOrigins)
}