package api

import (
	"net"
	"net/http"
	"net/url"
	"strings"

	"github.com/gorilla/websocket"
)

var upgrader = websocket.Upgrader{
	ReadBufferSize:  1024,
	WriteBufferSize: 1024,
	CheckOrigin: func(r *http.Request) bool {
		origin := r.Header.Get("Origin")
		if origin == "" {
			return true
		}
		originURL, err := url.Parse(origin)
		if err != nil {
			return false
		}
		originHost := strings.ToLower(stripPort(originURL.Host))
		requestHost := strings.ToLower(stripPort(r.Host))
		return originHost != "" && originHost == requestHost
	},
}

func stripPort(host string) string {
	if parsedHost, _, err := net.SplitHostPort(host); err == nil {
		return parsedHost
	}
	return strings.Trim(host, "[]")
}