// Licensed to the LF AI & Data foundation under one
// or more contributor license agreements. See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership. The ASF licenses this file
// to you 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 flusherimpl

import (
	"context"

	"github.com/cockroachdb/errors"
	"github.com/samber/lo"
	"go.uber.org/zap"

	"github.com/milvus-io/milvus-proto/go-api/v2/msgpb"
	"github.com/milvus-io/milvus/internal/distributed/streaming"
	"github.com/milvus-io/milvus/internal/flushcommon/util"
	"github.com/milvus-io/milvus/internal/flushcommon/writebuffer"
	"github.com/milvus-io/milvus/internal/streamingnode/server/resource"
	"github.com/milvus-io/milvus/pkg/v2/log"
	"github.com/milvus-io/milvus/pkg/v2/proto/internalpb"
	"github.com/milvus-io/milvus/pkg/v2/streaming/util/message"
	"github.com/milvus-io/milvus/pkg/v2/streaming/util/types"
	"github.com/milvus-io/milvus/pkg/v2/util/funcutil"
	"github.com/milvus-io/milvus/pkg/v2/util/merr"
	"github.com/milvus-io/milvus/pkg/v2/util/retry"
)

func newMsgHandler(wbMgr writebuffer.BufferManager) *msgHandlerImpl {
	return &msgHandlerImpl{
		wbMgr: wbMgr,
	}
}

type msgHandlerImpl struct {
	wbMgr writebuffer.BufferManager
}

func (impl *msgHandlerImpl) HandleCreateSegment(ctx context.Context, vchannel string, createSegmentMsg message.ImmutableCreateSegmentMessageV2) error {
	body, err := createSegmentMsg.Body()
	if err != nil {
		return errors.Wrap(err, "failed to get create segment message body")
	}
	for _, segmentInfo := range body.GetSegments() {
		if err := impl.wbMgr.CreateNewGrowingSegment(ctx, vchannel, segmentInfo.GetPartitionId(), segmentInfo.GetSegmentId()); err != nil {
			log.Warn("fail to create new growing segment",
				zap.String("vchannel", vchannel),
				zap.Int64("partition_id", segmentInfo.GetPartitionId()),
				zap.Int64("segment_id", segmentInfo.GetSegmentId()))
			return err
		}
		log.Info("create new growing segment",
			zap.String("vchannel", vchannel),
			zap.Int64("partition_id", segmentInfo.GetPartitionId()),
			zap.Int64("segment_id", segmentInfo.GetSegmentId()))
	}
	return nil
}

func (impl *msgHandlerImpl) HandleFlush(vchannel string, flushMsg message.ImmutableFlushMessageV2) error {
	body, err := flushMsg.Body()
	if err != nil {
		return errors.Wrap(err, "failed to get flush message body")
	}
	if err := impl.wbMgr.SealSegments(context.Background(), vchannel, body.GetSegmentId()); err != nil {
		return errors.Wrap(err, "failed to seal segments")
	}
	return nil
}

func (impl *msgHandlerImpl) HandleManualFlush(vchannel string, flushMsg message.ImmutableManualFlushMessageV2) error {
	if err := impl.wbMgr.FlushChannel(context.Background(), vchannel, flushMsg.Header().GetFlushTs()); err != nil {
		return errors.Wrap(err, "failed to flush channel")
	}
	return nil
}

func (impl *msgHandlerImpl) HandleImport(ctx context.Context, vchannel string, importMsg *msgpb.ImportMsg) error {
	return retry.Do(ctx, func() (err error) {
		defer func() {
			if err == nil {
				err = streaming.WAL().Broadcast().Ack(ctx, types.BroadcastAckRequest{
					BroadcastID: uint64(importMsg.GetJobID()),
					VChannel:    vchannel,
				})
			}
		}()
		client, err := resource.Resource().DataCoordClient().GetWithContext(ctx)
		if err != nil {
			return err
		}
		importResp, err := client.ImportV2(ctx, &internalpb.ImportRequestInternal{
			CollectionID:   importMsg.GetCollectionID(),
			CollectionName: importMsg.GetCollectionName(),
			PartitionIDs:   importMsg.GetPartitionIDs(),
			ChannelNames:   []string{vchannel},
			Schema:         importMsg.GetSchema(),
			Files:          lo.Map(importMsg.GetFiles(), util.ConvertInternalImportFile),
			Options:        funcutil.Map2KeyValuePair(importMsg.GetOptions()),
			DataTimestamp:  importMsg.GetBase().GetTimestamp(),
			JobID:          importMsg.GetJobID(),
		})
		err = merr.CheckRPCCall(importResp, err)
		if errors.Is(err, merr.ErrCollectionNotFound) {
			log.Ctx(ctx).Warn("import message failed because of collection not found, skip it", zap.String("job_id", importResp.GetJobID()), zap.Error(err))
			return nil
		}
		if err != nil {
			log.Ctx(ctx).Warn("import message failed", zap.String("job_id", importResp.GetJobID()), zap.Error(err))
			return err
		}
		log.Ctx(ctx).Info("import message handled", zap.String("job_id", importResp.GetJobID()))
		return nil
	}, retry.AttemptAlways())
}