config.go

// [Input] ~/.sshlogin/servers.json 配置文件
// [Output] 解析后的 Server/Group 结构体
// [Pos] 配置加载层，负责读取和校验 JSON 配置
package main

import (
	"encoding/json"
	"fmt"
	"os"
	"os/exec"
	"path/filepath"
	"strings"
)

// Server 单台服务器配置
type Server struct {
	Name     string `json:"name"`
	Host     string `json:"host"`
	Port     int    `json:"port"`
	User     string `json:"user"`
	Password string `json:"password"`
	Group    string `json:"-"` // 运行时填充，所属组名
}

// Group 服务器分组
type Group struct {
	Name    string   `json:"name"`
	Servers []Server `json:"servers"`
}

// Config 顶层配置结构
type Config struct {
	Groups []Group `json:"groups"`
}

// configPath 返回配置文件路径
func configPath() string {
	home, _ := os.UserHomeDir()
	return filepath.Join(home, ".sshlogin", "servers.json")
}

// exampleConfig 生成示例配置内容
func exampleConfig() []byte {
	cfg := Config{
		Groups: []Group{
			{
				Name: "生产环境",
				Servers: []Server{
					{Name: "Web Server", Host: "192.168.1.10", Port: 22, User: "root", Password: "your-password"},
				},
			},
			{
				Name: "测试环境",
				Servers: []Server{
					{Name: "Test Server", Host: "10.0.0.5", Port: 22, User: "test", Password: "test123"},
				},
			},
		},
	}
	data, _ := json.MarshalIndent(cfg, "", "  ")
	return data
}

// loadConfig 加载配置文件，若不存在则生成示例配置
func loadConfig() ([]Server, error) {
	path := configPath()
	data, err := os.ReadFile(path)
	if err != nil {
		if os.IsNotExist(err) {
			return nil, generateExampleConfig(path)
		}
		return nil, fmt.Errorf("read config failed: %w", err)
	}

	var cfg Config
	if err := json.Unmarshal(data, &cfg); err != nil {
		return nil, fmt.Errorf("parse config failed: %w", err)
	}

	// 展平分组为服务器列表
	var servers []Server
	for _, g := range cfg.Groups {
		for i := range g.Servers {
			s := &g.Servers[i]
			s.Group = g.Name
			if s.Port == 0 {
				s.Port = 22
			}
			s.Password = resolvePassword(s.Password)
			servers = append(servers, *s)
		}
	}

	if len(servers) == 0 {
		return nil, fmt.Errorf("no servers configured")
	}
	return servers, nil
}

// generateExampleConfig 生成示例配置文件
func generateExampleConfig(path string) error {
	dir := filepath.Dir(path)
	if err := os.MkdirAll(dir, 0700); err != nil {
		return fmt.Errorf("create config dir failed: %w", err)
	}
	data := exampleConfig()
	if err := os.WriteFile(path, data, 0600); err != nil {
		return fmt.Errorf("write example config failed: %w", err)
	}
	return fmt.Errorf("config not found, example created at %s\nPlease edit it and run again", path)
}

// resolvePassword 解析密码，支持 $ENV:VAR_NAME 格式
func resolvePassword(pwd string) string {
	if envName, ok := strings.CutPrefix(pwd, "$ENV:"); ok {
		if val := os.Getenv(envName); val != "" {
			return val
		}
	}
	return pwd
}

// checkSshpass 检查 sshpass 是否已安装
func checkSshpass() error {
	_, err := exec.LookPath("sshpass")
	if err != nil {
		return fmt.Errorf("sshpass not found, install with: brew install sshpass")
	}
	return nil
}