package etcd

import (
	"context"
	"reflect"
	"time"

	"go.etcd.io/etcd/client/v3"

	"mongo.games.com/goserver/core"
	"mongo.games.com/goserver/core/basic"
	"mongo.games.com/goserver/core/logger"

	"mongo.games.com/game/proto"
)

/*
 ETCD Manager
*/

var (
	defaultUrl         = []string{"localhost:2379"}
	defaultUser        = ""
	defaultPasswd      = ""
	defaultDialTimeout = time.Minute
)

var globalClient = new(Client)

// Register 注册etcd监听方法
// key:监听的key
// msgType:数据类型
// f:数据变更回调方法, completeKey:完整键, isInit:第一次主动拉取数据,event:事件类型, data:已经反序列化的数据，类型为msgType,是指针类型
func Register(key string, msgType interface{}, f func(ctx context.Context, completeKey string, isInit bool, event *clientv3.Event, data interface{})) {
	createFunc := func() interface{} {
		tp := reflect.TypeOf(msgType)
		if tp.Kind() == reflect.Ptr {
			tp = tp.Elem()
		}
		return reflect.New(tp).Interface()
	}

	initFunc := func() int64 {
		logger.Logger.Info("ETCD 拉取数据:", key)
		res, err := globalClient.GetValueWithPrefix(key)
		if err == nil {
			for i := int64(0); i < res.Count; i++ {
				data := createFunc()
				v, ok := data.(proto.Message)
				if !ok {
					logger.Logger.Errorf("ETCD %v error: not proto message", key)
					continue
				}
				err := proto.Unmarshal(res.Kvs[i].Value, v)
				if err != nil {
					logger.Logger.Errorf("ETCD %v unmarshal error:%v", key, err)
					continue
				}
				logger.Logger.Tracef("ETCD 拉取成功 %v ==> %v", string(res.Kvs[i].Key), v)
				event := &clientv3.Event{
					Type: 0,
				}
				f(context.TODO(), string(res.Kvs[i].Key), true, event, v)
			}
			if res.Header != nil {
				return res.Header.Revision
			}
		} else {
			logger.Logger.Errorf("ETCD get WithPrefix(%v) panic:%v", key, err)
		}
		return -1
	}

	// 监控数据变动
	watchFunc := func(ctx context.Context, revision int64) {
		globalClient.GoWatch(ctx, revision, key, func(res clientv3.WatchResponse) error {
			obj := core.CoreObject()
			if obj != nil {
				obj.SendCommand(basic.CommandWrapper(func(*basic.Object) error {
					for _, ev := range res.Events {
						switch ev.Type {
						case clientv3.EventTypePut:
							data := createFunc()
							v, ok := data.(proto.Message)
							if !ok {
								logger.Logger.Errorf("ETCD %v error: not proto message", string(ev.Kv.Key))
								continue
							}
							err := proto.Unmarshal(ev.Kv.Value, v)
							if err != nil {
								logger.Logger.Errorf("etcd unmarshal(%v) error:%v", string(ev.Kv.Key), err)
								continue
							}
							logger.Logger.Tracef("ETCD 更新事件 %v ==> %v", string(ev.Kv.Key), v)
							f(ctx, string(ev.Kv.Key), false, ev, v)
						case clientv3.EventTypeDelete:
							logger.Logger.Tracef("ETCD 删除事件 %v", string(ev.Kv.Key))
							f(ctx, string(ev.Kv.Key), false, ev, nil)
						}
					}
					return nil
				}), true)
			}
			return nil
		})
	}

	globalClient.AddFunc(initFunc, watchFunc)
}

func Reset() {
	globalClient.Close()
	Start(defaultUrl, defaultUser, defaultPasswd, defaultDialTimeout)
}

func Close() {
	globalClient.Close()
}

func Start(url []string, user, passwd string, dialTimeout time.Duration) {
	defaultUrl = url
	defaultUser = user
	defaultPasswd = passwd
	if dialTimeout > 0 {
		defaultDialTimeout = dialTimeout
	}

	err := globalClient.Open(defaultUrl, defaultUser, defaultPasswd, defaultDialTimeout)
	if err != nil {
		logger.Logger.Errorf("etcd.Open err:%v", err)
	}
	globalClient.ReInitAndWatchAll()
}