package config

import (
	"fmt"
	"io/ioutil"
	"time"

	"gopkg.in/yaml.v3"
)

// Config 客户端配置结构
type Config struct {
	ServiceType      string           `yaml:"serviceType"`
	Server           Server           `yaml:"server"`
	Proxy            Proxy            `yaml:"proxy"`
	GlobalProxy      GlobalProxy      `yaml:"globalProxy"`
	TransparentProxy TransparentProxy `yaml:"transparentProxy"`
	LogLevel         string           `yaml:"logLevel"`
	Timeout          time.Duration    `yaml:"timeout"`
}

// Server SOCKS5服务器配置
type Server struct {
	Address  string `yaml:"address"`
	Port     int    `yaml:"port"`
	Username string `yaml:"username"`
	Password string `yaml:"password"`
}

// Proxy 代理模式配置
type Proxy struct {
	Mode      string `yaml:"mode"`
	LocalPort int    `yaml:"localPort"`
}

// GlobalProxy 全局代理配置
type GlobalProxy struct {
	Enabled  bool    `yaml:"enabled"`
	DNSProxy bool    `yaml:"dnsProxy"`
	DNSPort  int     `yaml:"dnsPort"`
	Routing  Routing `yaml:"routing"`
}

// TransparentProxy 透明代理配置
type TransparentProxy struct {
	Enabled     bool `yaml:"enabled"`
	Port        int  `yaml:"port"`
	DNSPort     int  `yaml:"dnsPort"`
	ModifyDNS   bool `yaml:"modifyDNS"`
	ModifyRoute bool `yaml:"modifyRoute"`
}

// Routing 路由规则配置
type Routing struct {
	BypassLocal   bool     `yaml:"bypassLocal"`
	BypassPrivate bool     `yaml:"bypassPrivate"`
	BypassDomains []string `yaml:"bypassDomains"`
	ForceDomains  []string `yaml:"forceDomains"`
}

// LoadConfig 从文件加载配置
func LoadConfig(configPath string) (*Config, error) {
	data, err := ioutil.ReadFile(configPath)
	if err != nil {
		return nil, fmt.Errorf("failed to read config file: %v", err)
	}

	var config Config
	if err := yaml.Unmarshal(data, &config); err != nil {
		return nil, fmt.Errorf("failed to parse config file: %v", err)
	}

	// 设置默认值
	if config.LogLevel == "" {
		config.LogLevel = "info"
	}
	if config.Timeout == 0 {
		config.Timeout = 30 * time.Second
	}
	if config.Proxy.LocalPort == 0 {
		config.Proxy.LocalPort = 8080
	}

	return &config, nil
}

// GetServerAddr 获取服务器地址
func (c *Config) GetServerAddr() string {
	return fmt.Sprintf("%s:%d", c.Server.Address, c.Server.Port)
}

// Validate 验证配置
func (c *Config) Validate() error {
	if c.Server.Address == "" {
		return fmt.Errorf("server address is required")
	}
	if c.Server.Port <= 0 || c.Server.Port > 65535 {
		return fmt.Errorf("invalid server port: %d", c.Server.Port)
	}

	validModes := map[string]bool{"http": true, "global": true, "transparent": true}
	if !validModes[c.Proxy.Mode] {
		return fmt.Errorf("invalid proxy mode: %s", c.Proxy.Mode)
	}

	return nil
}