package server

import (
	"context"
	"errors"
	"net"
	"sync"
	"time"
)

// 尝试连接到 address, 连接成功后不会发送任何数据
func pingServer(ctx context.Context, address string) error {
	dialer := net.Dialer{
		Timeout:         2*time.Second,
	}
	conn, err := dialer.DialContext(ctx, "tcp", address)
	if err != nil {
		return err
	}
	_ = conn.Close()
	return nil
}

// ConnectTest 尝试连接服务器是否连通
func ConnectTest(ctx context.Context, servers []string) error {
	errs := make(chan error, len(servers))
	var wg sync.WaitGroup
	wg.Add(len(servers))
	for _, server := range servers {
		wg.Go(func() {
			if err := pingServer(ctx, server); err != nil {
				errs <- err
			}
			wg.Done()
		})
	}
	wg.Wait()
	close(errs)
	var retErr error
	for err := range errs {
		retErr = errors.Join(retErr, err)
	}
	return retErr
}