refactor cluster connection in CLI

internal/cli/config/connection.go

@@ -0,0 +1,46 @@
+package config
+
+import (
+	"net"
+	"strconv"
+	"strings"
+	"uncloud/internal/secret"
+)
+
+const (
+	DefaultSSHUser = "root"
+	DefaultSSHPort = 22
+)
+
+type MachineConnection struct {
+	SSH       SSHDestination `toml:"ssh,omitempty"`
+	Host      string         `toml:"host,omitempty"`
+	PublicKey secret.Secret  `toml:"public_key,omitempty"`
+}
+
+type SSHDestination string
+
+func NewSSHDestination(user, host string, port int) SSHDestination {
+	dst := host
+	if port != 0 && port != DefaultSSHPort {
+		dst = net.JoinHostPort(host, strconv.Itoa(port))
+	}
+	if user == "" {
+		user = DefaultSSHUser
+	}
+	dst = user + "@" + dst
+	return SSHDestination(dst)
+}
+
+func (d SSHDestination) Parse() (user string, host string, port int, err error) {
+	host = string(d)
+	if strings.Contains(host, "@") {
+		user, host, _ = strings.Cut(host, "@")
+	}
+	h, p, sErr := net.SplitHostPort(host)
+	if sErr == nil {
+		host = h
+		port, err = strconv.Atoi(p)
+	}
+	return
+}