package config

import (
	"encoding/json"
	"io/ioutil"
)

// DNSConfig DNS服务器配置
type DNSConfig struct {
	Port        int      `json:"port"`
	UpstreamDNS []string `json:"upstreamDNS"`
	Timeout     int      `json:"timeout"`
}

// HTTPConfig HTTP控制台配置
type HTTPConfig struct {
	Port      int    `json:"port"`
	Host      string `json:"host"`
	EnableAPI bool   `json:"enableAPI"`
}

// ShieldConfig 屏蔽规则配置
type ShieldConfig struct {
	LocalRulesFile string   `json:"localRulesFile"`
	RemoteRules    []string `json:"remoteRules"`
	UpdateInterval int      `json:"updateInterval"`
	HostsFile      string   `json:"hostsFile"`
	BlockMethod    string   `json:"blockMethod"`   // 屏蔽方法: "NXDOMAIN", "refused", "emptyIP", "customIP"
	CustomBlockIP  string   `json:"customBlockIP"` // 自定义屏蔽IP，当BlockMethod为"customIP"时使用
}

// LogConfig 日志配置
type LogConfig struct {
	File       string `json:"file"`
	Level      string `json:"level"`
	MaxSize    int    `json:"maxSize"`
	MaxBackups int    `json:"maxBackups"`
	MaxAge     int    `json:"maxAge"`
}

// Config 整体配置
type Config struct {
	DNS    DNSConfig    `json:"dns"`
	HTTP   HTTPConfig   `json:"http"`
	Shield ShieldConfig `json:"shield"`
	Log    LogConfig    `json:"log"`
}

// LoadConfig 加载配置文件
func LoadConfig(path string) (*Config, error) {
	data, err := ioutil.ReadFile(path)
	if err != nil {
		return nil, err
	}

	var config Config
	err = json.Unmarshal(data, &config)
	if err != nil {
		return nil, err
	}

	// 设置默认值
	if config.DNS.Port == 0 {
		config.DNS.Port = 53
	}
	if len(config.DNS.UpstreamDNS) == 0 {
		config.DNS.UpstreamDNS = []string{"8.8.8.8:53", "1.1.1.1:53"}
	}
	if config.HTTP.Port == 0 {
		config.HTTP.Port = 8080
	}
	if config.HTTP.Host == "" {
		config.HTTP.Host = "0.0.0.0"
	}
	if config.Shield.UpdateInterval == 0 {
		config.Shield.UpdateInterval = 3600
	}
	if config.Shield.BlockMethod == "" {
		config.Shield.BlockMethod = "NXDOMAIN" // 默认屏蔽方法为NXDOMAIN
	}
	if config.Log.Level == "" {
		config.Log.Level = "info"
	}

	return &config, nil
}