package msgstream

import (
	"sync"

	"github.com/zilliztech/milvus-distributed/internal/errors"
	"github.com/zilliztech/milvus-distributed/internal/proto/commonpb"
	"github.com/zilliztech/milvus-distributed/internal/proto/internalpb2"
	"github.com/zilliztech/milvus-distributed/internal/util/typeutil"
)

type UniqueID = typeutil.UniqueID
type Timestamp = typeutil.Timestamp
type IntPrimaryKey = typeutil.IntPrimaryKey

type MsgPack struct {
	BeginTs Timestamp
	EndTs   Timestamp
	Msgs    []TsMsg
}

type RepackFunc func(msgs []TsMsg, hashKeys [][]int32) (map[int32]*MsgPack, error)

type MsgStream interface {
	Start()
	Close()

	Produce(*MsgPack) error
	Broadcast(*MsgPack) error
	Consume() *MsgPack
	Chan() <-chan *MsgPack
}

//TODO test InMemMsgStream
/*
type InMemMsgStream struct {
	buffer chan *MsgPack
}

func (ms *InMemMsgStream) Start() {}
func (ms *InMemMsgStream) Close() {}

func (ms *InMemMsgStream) ProduceOne(msg TsMsg) error {
	msgPack := MsgPack{}
	msgPack.BeginTs = msg.BeginTs()
	msgPack.EndTs = msg.EndTs()
	msgPack.Msgs = append(msgPack.Msgs, msg)
	buffer <- &msgPack
	return nil
}

func (ms *InMemMsgStream) Produce(msgPack *MsgPack) error {
	buffer <- msgPack
	return nil
}

func (ms *InMemMsgStream) Broadcast(msgPack *MsgPack) error {
	return ms.Produce(msgPack)
}

func (ms *InMemMsgStream) Consume() *MsgPack {
	select {
	case msgPack := <-ms.buffer:
		return msgPack
	}
}

func (ms *InMemMsgStream) Chan() <- chan *MsgPack {
	return buffer
}
*/

func CheckTimeTickMsg(msg map[int]Timestamp, isChannelReady []bool, mu *sync.RWMutex) (Timestamp, bool) {
	checkMap := make(map[Timestamp]int)
	var maxTime Timestamp = 0
	for _, v := range msg {
		checkMap[v]++
		if v > maxTime {
			maxTime = v
		}
	}
	if len(checkMap) <= 1 {
		for i := range msg {
			isChannelReady[i] = false
		}
		return maxTime, true
	}
	for i := range msg {
		mu.RLock()
		v := msg[i]
		mu.Unlock()
		if v != maxTime {
			isChannelReady[i] = false
		} else {
			isChannelReady[i] = true
		}
	}

	return 0, false
}

func InsertRepackFunc(tsMsgs []TsMsg, hashKeys [][]int32) (map[int32]*MsgPack, error) {
	result := make(map[int32]*MsgPack)
	for i, request := range tsMsgs {
		if request.Type() != commonpb.MsgType_kInsert {
			return nil, errors.New("msg's must be Insert")
		}
		insertRequest := request.(*InsertMsg)
		keys := hashKeys[i]

		timestampLen := len(insertRequest.Timestamps)
		rowIDLen := len(insertRequest.RowIDs)
		rowDataLen := len(insertRequest.RowData)
		keysLen := len(keys)

		if keysLen != timestampLen || keysLen != rowIDLen || keysLen != rowDataLen {
			return nil, errors.New("the length of hashValue, timestamps, rowIDs, RowData are not equal")
		}
		for index, key := range keys {
			_, ok := result[key]
			if !ok {
				msgPack := MsgPack{}
				result[key] = &msgPack
			}

			sliceRequest := internalpb2.InsertRequest{
				Base: &commonpb.MsgBase{
					MsgType:   commonpb.MsgType_kInsert,
					MsgID:     insertRequest.Base.MsgID,
					Timestamp: insertRequest.Timestamps[index],
					SourceID:  insertRequest.Base.SourceID,
				},
				CollectionName: insertRequest.CollectionName,
				PartitionName:  insertRequest.PartitionName,
				SegmentID:      insertRequest.SegmentID,
				ChannelID:      insertRequest.ChannelID,
				Timestamps:     []uint64{insertRequest.Timestamps[index]},
				RowIDs:         []int64{insertRequest.RowIDs[index]},
				RowData:        []*commonpb.Blob{insertRequest.RowData[index]},
			}

			insertMsg := &InsertMsg{
				BaseMsg: BaseMsg{
					MsgCtx: request.GetMsgContext(),
				},
				InsertRequest: sliceRequest,
			}
			result[key].Msgs = append(result[key].Msgs, insertMsg)
		}
	}
	return result, nil
}

func DeleteRepackFunc(tsMsgs []TsMsg, hashKeys [][]int32) (map[int32]*MsgPack, error) {
	result := make(map[int32]*MsgPack)
	for i, request := range tsMsgs {
		if request.Type() != commonpb.MsgType_kDelete {
			return nil, errors.New("msg's must be Delete")
		}
		deleteRequest := request.(*DeleteMsg)
		keys := hashKeys[i]

		timestampLen := len(deleteRequest.Timestamps)
		primaryKeysLen := len(deleteRequest.PrimaryKeys)
		keysLen := len(keys)

		if keysLen != timestampLen || keysLen != primaryKeysLen {
			return nil, errors.New("the length of hashValue, timestamps, primaryKeys are not equal")
		}

		for index, key := range keys {
			_, ok := result[key]
			if !ok {
				msgPack := MsgPack{}
				result[key] = &msgPack
			}

			sliceRequest := internalpb2.DeleteRequest{
				Base: &commonpb.MsgBase{
					MsgType:   commonpb.MsgType_kDelete,
					MsgID:     deleteRequest.Base.MsgID,
					Timestamp: deleteRequest.Timestamps[index],
					SourceID:  deleteRequest.Base.SourceID,
				},
				CollectionName: deleteRequest.CollectionName,
				ChannelID:      deleteRequest.ChannelID,
				Timestamps:     []uint64{deleteRequest.Timestamps[index]},
				PrimaryKeys:    []int64{deleteRequest.PrimaryKeys[index]},
			}

			deleteMsg := &DeleteMsg{
				BaseMsg: BaseMsg{
					MsgCtx: request.GetMsgContext(),
				},
				DeleteRequest: sliceRequest,
			}
			result[key].Msgs = append(result[key].Msgs, deleteMsg)
		}
	}
	return result, nil
}

func DefaultRepackFunc(tsMsgs []TsMsg, hashKeys [][]int32) (map[int32]*MsgPack, error) {
	result := make(map[int32]*MsgPack)
	for i, request := range tsMsgs {
		keys := hashKeys[i]
		if len(keys) != 1 {
			return nil, errors.New("len(msg.hashValue) must equal 1")
		}
		key := keys[0]
		_, ok := result[key]
		if !ok {
			msgPack := MsgPack{}
			result[key] = &msgPack
		}
		result[key].Msgs = append(result[key].Msgs, request)
	}
	return result, nil
}