package etcd

import (
	"context"
	"encoding/json"
	"fmt"
	clientv3 "go.etcd.io/etcd/client/v3"
	"time"
)

var (
	cli *clientv3.Client
)

//需要手机的日志的配置信息

type LogEntry struct {
	Path  string `json:"path"`  //日志存放的路径
	Topic string `json:"topic"` //日志要发往kafka中的哪个Topic
}

//初始化etcd

func Init(addr string, timeout time.Duration) (err error) {
	cli, err = clientv3.New(clientv3.Config{
		Endpoints:   []string{addr},
		DialTimeout: timeout,
	})
	if err != nil {
		//handle error!
		fmt.Println("connect etcd server failed,error:", err)
		return
	}
	fmt.Println("connect etcd server success")
	return
}

// 从etcd中根据key获取配置项

func GetConf(key string) (logEntryConf []*LogEntry, err error) {

	ctx, cancel := context.WithTimeout(context.Background(), time.Second)
	resp, err := cli.Get(ctx, key)
	cancel()
	if err != nil {
		fmt.Println("get etcd config failed,error:", err)
	}
	for _, ev := range resp.Kvs {
		err = json.Unmarshal(ev.Value, &logEntryConf)
		if err != nil {
			fmt.Println("parse etcd config failed,error:", err)
			return
		}
	}
	return
}

//etcd的哨兵

func Watcher(key string, newConfCh chan<- []*LogEntry) {
	ch := cli.Watch(context.Background(), key)
	for w := range ch {
		for _, evt := range w.Events {
			fmt.Printf("index:%v value:%v\n", evt.Type, string(evt.Kv.Value))
			//通知taillog.tailTskMgr
			//1.先判断操作的类型
			var newConf []*LogEntry
			if evt.Type != clientv3.EventTypeDelete {
				err := json.Unmarshal(evt.Kv.Value, &newConf)
				if err != nil {
					fmt.Println("parse etcd config failed,error:", err)
					continue
				}
			}
			fmt.Println("get etcd new config success", newConf)
			newConfCh <- newConf

		}
	}
}