package blobovniczatree

import (
	"context"
	"errors"
	"path/filepath"
	"time"

	"git.frostfs.info/TrueCloudLab/frostfs-node/internal/logs"
	"git.frostfs.info/TrueCloudLab/frostfs-node/pkg/local_object_storage/blobovnicza"
	"git.frostfs.info/TrueCloudLab/frostfs-node/pkg/local_object_storage/blobstor/common"
	tracingPkg "git.frostfs.info/TrueCloudLab/frostfs-node/pkg/tracing"
	"git.frostfs.info/TrueCloudLab/frostfs-observability/tracing"
	"go.opentelemetry.io/otel/attribute"
	"go.opentelemetry.io/otel/trace"
	"go.uber.org/zap"
)

// Put saves object in the maximum weight blobobnicza.
//
// returns error if could not save object in any blobovnicza.
func (b *Blobovniczas) Put(ctx context.Context, prm common.PutPrm) (common.PutRes, error) {
	var (
		success   bool
		size      int
		startedAt = time.Now()
	)
	defer func() {
		b.metrics.Put(time.Since(startedAt), size, success)
	}()

	_, span := tracing.StartSpanFromContext(ctx, "Blobovniczas.Put",
		trace.WithAttributes(
			attribute.String("address", prm.Address.EncodeToString()),
			attribute.Bool("dont_compress", prm.DontCompress),
		))
	defer span.End()

	if b.readOnly {
		return common.PutRes{}, common.ErrReadOnly
	}

	if !prm.DontCompress {
		prm.RawData = b.compression.Compress(prm.RawData)
	}
	size = len(prm.RawData)

	var putPrm blobovnicza.PutPrm
	putPrm.SetAddress(prm.Address)
	putPrm.SetMarshaledObject(prm.RawData)

	it := &putIterator{
		B:       b,
		ID:      nil,
		AllFull: true,
		PutPrm:  putPrm,
	}

	if err := b.iterateDeepest(ctx, prm.Address, func(s string) (bool, error) { return it.iterate(ctx, s) }); err != nil {
		return common.PutRes{}, err
	} else if it.ID == nil {
		if it.AllFull {
			return common.PutRes{}, common.ErrNoSpace
		}
		return common.PutRes{}, errPutFailed
	}

	success = true
	return common.PutRes{StorageID: it.ID.Bytes()}, nil
}

type putIterator struct {
	B       *Blobovniczas
	ID      *ID
	AllFull bool
	PutPrm  blobovnicza.PutPrm
}

func (i *putIterator) iterate(ctx context.Context, lvlPath string) (bool, error) {
	active, err := i.B.activeDBManager.GetOpenedActiveDBForLevel(lvlPath)
	if err != nil {
		if !isLogical(err) {
			i.B.reportError(logs.BlobovniczatreeCouldNotGetActiveBlobovnicza, err)
		} else {
			i.B.log.Debug(logs.BlobovniczatreeCouldNotGetActiveBlobovnicza,
				zap.String("error", err.Error()),
				zap.String("trace_id", tracingPkg.GetTraceID(ctx)))
		}

		return false, nil
	}

	if active == nil {
		i.B.log.Debug(logs.BlobovniczatreeBlobovniczaOverflowed, zap.String("level", lvlPath),
			zap.String("trace_id", tracingPkg.GetTraceID(ctx)))
		return false, nil
	}
	defer active.Close()

	i.AllFull = false

	_, err = active.Blobovnicza().Put(ctx, i.PutPrm)
	if err != nil {
		if !isLogical(err) {
			i.B.reportError(logs.BlobovniczatreeCouldNotPutObjectToActiveBlobovnicza, err)
		} else {
			i.B.log.Debug(logs.BlobovniczatreeCouldNotPutObjectToActiveBlobovnicza,
				zap.String("path", active.SystemPath()),
				zap.String("error", err.Error()),
				zap.String("trace_id", tracingPkg.GetTraceID(ctx)))
		}
		if errors.Is(err, blobovnicza.ErrNoSpace) {
			i.AllFull = true
		}
		return false, nil
	}

	idx := u64FromHexString(filepath.Base(active.SystemPath()))
	i.ID = NewIDFromBytes([]byte(filepath.Join(lvlPath, u64ToHexString(idx))))

	return true, nil
}