// Copyright (C) 2019-2020 Zilliz. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance
// with the License. You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software distributed under the License
// is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
// or implied. See the License for the specific language governing permissions and limitations under the License.

package tsoutil

import (
	"path"
	"time"

	etcdkv "github.com/milvus-io/milvus/internal/kv/etcd"
	"go.etcd.io/etcd/clientv3"
)

const (
	logicalBits     = 18
	logicalBitsMask = (1 << logicalBits) - 1
)

func ComposeTS(physical, logical int64) uint64 {
	return uint64((physical << logicalBits) + logical)
}

// ParseTS parses the ts to (physical,logical).
func ParseTS(ts uint64) (time.Time, uint64) {
	logical := ts & logicalBitsMask
	physical := ts >> logicalBits
	physicalTime := time.Unix(int64(physical/1000), int64(physical)%1000*time.Millisecond.Nanoseconds())
	return physicalTime, logical
}

func NewTSOKVBase(etcdAddr []string, tsoRoot, subPath string) *etcdkv.EtcdKV {
	client, _ := clientv3.New(clientv3.Config{
		Endpoints:   etcdAddr,
		DialTimeout: 5 * time.Second,
	})
	return etcdkv.NewEtcdKV(client, path.Join(tsoRoot, subPath))
}