package config

import (
	"fmt"
	"net"
	"net/url"
	"strconv"
	"strings"

	"git.apinb.com/bsm-sdk/core/conf"
)

var Spec SrvConfig

type AlertForwardConf struct {
	BaseURL         string `yaml:"base_url"`
	InternalKey     string `yaml:"internal_key"`
	Enabled         bool   `yaml:"enabled"`
	DefaultPolicyID uint   `yaml:"default_policy_id"`
}

type IngestConf struct {
	SyslogListenAddr string `yaml:"syslog_listen_addr"`
	TrapListenAddr   string `yaml:"trap_listen_addr"`
	RuleRefreshSecs  int    `yaml:"rule_refresh_secs"`
}

type ResourceEventConf struct {
	// HMACSecret 用于校验 dc-control 推送签名（X-Event-Signature）。
	HMACSecret string `yaml:"hmac_secret"`
	// MaxSkewSecs 允许事件时间与服务端时间的最大偏差（秒）。
	MaxSkewSecs int `yaml:"max_skew_secs"`
}

type OTLPConf struct {
	InternalKey string `yaml:"internal_key"`
}

type SystemSettingsConf struct {
	BaseURL        string `yaml:"base_url"`
	RefreshSeconds int    `yaml:"refresh_seconds"`
	TimeoutSeconds int    `yaml:"timeout_seconds"`
}

type SrvConfig struct {
	conf.Base      `yaml:",inline"`
	Databases      *conf.DBConf            `yaml:"Databases"`
	MicroService   *conf.MicroServiceConf  `yaml:"MicroService"`
	Rpc            map[string]conf.RpcConf `yaml:"Rpc"`
	Gateway        *conf.GatewayConf       `yaml:"Gateway"`
	Apm            *conf.ApmConf           `yaml:"APM"`
	AlertForward   *AlertForwardConf       `yaml:"AlertForward"`
	Ingest         IngestConf              `yaml:"Ingest"`
	ResourceEvent  ResourceEventConf       `yaml:"ResourceEvent"`
	OTLP           OTLPConf                `yaml:"OTLP"`
	SystemSettings SystemSettingsConf      `yaml:"SystemSettings"`
}

func New(srvKey string) {
	conf.New(srvKey, &Spec)
	if err := Validate(); err != nil {
		panic(fmt.Errorf("logs 配置校验失败: %w", err))
	}
	Spec.Addr = net.JoinHostPort(Spec.BindIP, Spec.Port)
	conf.PrintInfo(Spec.Addr)
}

// Validate 校验日志服务配置，不生成随机端口、监听地址或刷新间隔。
func Validate() error {
	Spec.Service = strings.TrimSpace(Spec.Service)
	Spec.Port = strings.TrimSpace(Spec.Port)
	Spec.BindIP = strings.TrimSpace(Spec.BindIP)
	Spec.ResourceEvent.HMACSecret = strings.TrimSpace(Spec.ResourceEvent.HMACSecret)
	Spec.OTLP.InternalKey = strings.TrimSpace(Spec.OTLP.InternalKey)
	Spec.SystemSettings.BaseURL = strings.TrimRight(strings.TrimSpace(Spec.SystemSettings.BaseURL), "/")
	if Spec.Service == "" {
		return fmt.Errorf("Service 不能为空")
	}
	port, err := strconv.Atoi(Spec.Port)
	if err != nil || port < 1 || port > 65535 {
		return fmt.Errorf("Port 必须是 1 到 65535 的整数")
	}
	if net.ParseIP(Spec.BindIP) == nil {
		return fmt.Errorf("BindIP 必须是明确的 IPv4 或 IPv6 地址")
	}
	if Spec.Databases == nil || strings.TrimSpace(Spec.Databases.Driver) == "" || len(Spec.Databases.Source) == 0 {
		return fmt.Errorf("Databases.Driver 和 Databases.Source 不能为空")
	}
	if strings.TrimSpace(Spec.Cache) == "" {
		return fmt.Errorf("Cache 不能为空")
	}
	if Spec.ResourceEvent.HMACSecret == "" || Spec.ResourceEvent.MaxSkewSecs <= 0 {
		return fmt.Errorf("ResourceEvent.hmac_secret 和 max_skew_secs 必须有效")
	}
	if Spec.OTLP.InternalKey == "" {
		return fmt.Errorf("OTLP.internal_key 不能为空")
	}
	parsedSystemSettingsURL, err := url.Parse(Spec.SystemSettings.BaseURL)
	if err != nil || parsedSystemSettingsURL.Host == "" || (parsedSystemSettingsURL.Scheme != "http" && parsedSystemSettingsURL.Scheme != "https") {
		return fmt.Errorf("SystemSettings.base_url 必须是完整的 HTTP 或 HTTPS 地址")
	}
	if Spec.SystemSettings.RefreshSeconds <= 0 || Spec.SystemSettings.TimeoutSeconds <= 0 {
		return fmt.Errorf("SystemSettings.refresh_seconds 和 timeout_seconds 必须大于 0")
	}
	if Spec.Ingest.RuleRefreshSecs <= 0 {
		return fmt.Errorf("Ingest.rule_refresh_secs 必须大于 0")
	}
	for name, addr := range map[string]string{
		"syslog_listen_addr": Spec.Ingest.SyslogListenAddr,
		"trap_listen_addr":   Spec.Ingest.TrapListenAddr,
	} {
		addr = strings.TrimSpace(addr)
		if addr == "" {
			continue
		}
		if _, err := net.ResolveUDPAddr("udp", addr); err != nil {
			return fmt.Errorf("Ingest.%s 无效: %w", name, err)
		}
	}
	if Spec.AlertForward != nil && Spec.AlertForward.Enabled {
		Spec.AlertForward.BaseURL = strings.TrimSpace(Spec.AlertForward.BaseURL)
		Spec.AlertForward.InternalKey = strings.TrimSpace(Spec.AlertForward.InternalKey)
		parsed, err := url.Parse(Spec.AlertForward.BaseURL)
		if err != nil || parsed.Host == "" || (parsed.Scheme != "http" && parsed.Scheme != "https") {
			return fmt.Errorf("AlertForward.base_url 必须是完整的 HTTP 或 HTTPS 地址")
		}
		if Spec.AlertForward.InternalKey == "" {
			return fmt.Errorf("AlertForward.internal_key 不能为空")
		}
	}
	return nil
}