package adapters

import (
	"crypto/tls"
	"fmt"
	"net"
	"net/url"
	"sync"
	"time"

	C "github.com/Dreamacro/clash/constant"
)

const (
	tcpTimeout = 5 * time.Second
)

var (
	globalClientSessionCache tls.ClientSessionCache
	once                     sync.Once
)

func urlToMetadata(rawURL string) (addr C.Metadata, err error) {
	u, err := url.Parse(rawURL)
	if err != nil {
		return
	}

	port := u.Port()
	if port == "" {
		if u.Scheme == "https" {
			port = "443"
		} else if u.Scheme == "http" {
			port = "80"
		} else {
			err = fmt.Errorf("%s scheme not Support", rawURL)
			return
		}
	}

	addr = C.Metadata{
		AddrType: C.AtypDomainName,
		Host:     u.Hostname(),
		IP:       nil,
		Port:     port,
	}
	return
}

func tcpKeepAlive(c net.Conn) {
	if tcp, ok := c.(*net.TCPConn); ok {
		tcp.SetKeepAlive(true)
		tcp.SetKeepAlivePeriod(30 * time.Second)
	}
}

func getClientSessionCache() tls.ClientSessionCache {
	once.Do(func() {
		globalClientSessionCache = tls.NewLRUClientSessionCache(128)
	})
	return globalClientSessionCache
}