// 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 job

import (
	"context"
	"time"

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

	"github.com/milvus-io/milvus/internal/querycoordv2/checkers"
	"github.com/milvus-io/milvus/internal/querycoordv2/meta"
	"github.com/milvus-io/milvus/internal/querycoordv2/observers"
	"github.com/milvus-io/milvus/pkg/log"
	"github.com/milvus-io/milvus/pkg/util/typeutil"
)

// waitCollectionReleased blocks until
// all channels and segments of given collection(partitions) are released,
// empty partition list means wait for collection released
func waitCollectionReleased(dist *meta.DistributionManager, checkerController *checkers.CheckerController, collection int64, partitions ...int64) {
	partitionSet := typeutil.NewUniqueSet(partitions...)
	for {
		var (
			channels []*meta.DmChannel
			segments []*meta.Segment = dist.SegmentDistManager.GetByFilter(meta.WithCollectionID(collection))
		)
		if partitionSet.Len() > 0 {
			segments = lo.Filter(segments, func(segment *meta.Segment, _ int) bool {
				return partitionSet.Contain(segment.GetPartitionID())
			})
		} else {
			channels = dist.ChannelDistManager.GetByCollectionAndFilter(collection)
		}

		if len(channels)+len(segments) == 0 {
			break
		} else {
			log.Info("wait for release done", zap.Int64("collection", collection),
				zap.Int64s("partitions", partitions),
				zap.Int("channel", len(channels)),
				zap.Int("segments", len(segments)),
			)
		}

		// trigger check more frequently
		checkerController.Check()
		time.Sleep(200 * time.Millisecond)
	}
}

func waitCurrentTargetUpdated(ctx context.Context, targetObserver *observers.TargetObserver, collection int64) error {
	// manual trigger update next target
	ready, err := targetObserver.UpdateNextTarget(collection)
	if err != nil {
		log.Warn("failed to update next target for sync partition job", zap.Error(err))
		return err
	}

	// accelerate check
	targetObserver.TriggerUpdateCurrentTarget(collection)
	// wait current target ready
	select {
	case <-ready:
		return nil
	case <-ctx.Done():
		return ctx.Err()
	}
}