package writecache

import (
	"context"
	"time"

	"git.frostfs.info/TrueCloudLab/frostfs-node/pkg/local_object_storage/blobstor/common"
	storagelog "git.frostfs.info/TrueCloudLab/frostfs-node/pkg/local_object_storage/internal/log"
	"git.frostfs.info/TrueCloudLab/frostfs-node/pkg/local_object_storage/internal/metaerr"
	"git.frostfs.info/TrueCloudLab/frostfs-observability/tracing"
	"go.opentelemetry.io/otel/attribute"
	"go.opentelemetry.io/otel/trace"
)

// Put puts object to write-cache.
//
// Returns ErrReadOnly if write-cache is in R/O mode.
// Returns ErrNotInitialized if write-cache has not been initialized yet.
// Returns ErrOutOfSpace if saving an object leads to WC's size overflow.
// Returns ErrBigObject if an objects exceeds maximum object size.
func (c *cache) Put(ctx context.Context, prm common.PutPrm) (common.PutRes, error) {
	ctx, span := tracing.StartSpanFromContext(ctx, "writecache.Put",
		trace.WithAttributes(
			attribute.String("address", prm.Address.EncodeToString()),
			attribute.Bool("dont_compress", prm.DontCompress),
		))
	defer span.End()

	startedAt := time.Now()
	added := false
	storageType := StorageTypeUndefined
	defer func() {
		c.metrics.Put(time.Since(startedAt), added, storageType)
	}()

	if !c.modeMtx.TryRLock() {
		return common.PutRes{}, ErrNotInitialized
	}
	defer c.modeMtx.RUnlock()
	if c.readOnly() {
		return common.PutRes{}, ErrReadOnly
	}
	if c.noMetabase() {
		return common.PutRes{}, ErrDegraded
	}

	sz := uint64(len(prm.RawData))
	if sz > c.maxObjectSize {
		return common.PutRes{}, ErrBigObject
	}

	storageType = StorageTypeFSTree
	err := c.putBig(ctx, prm)
	if err == nil {
		added = true
	}
	return common.PutRes{}, metaerr.Wrap(err)
}

// putBig writes object to FSTree and pushes it to the flush workers queue.
func (c *cache) putBig(ctx context.Context, prm common.PutPrm) error {
	if !c.hasEnoughSpaceFS() {
		return ErrOutOfSpace
	}

	_, err := c.fsTree.Put(ctx, prm)
	if err != nil {
		return err
	}

	storagelog.Write(ctx, c.log,
		storagelog.AddressField(prm.Address.EncodeToString()),
		storagelog.StorageTypeField(wcStorageType),
		storagelog.OpField("fstree PUT"),
	)
	// counter changed by fstree
	c.estimateCacheSize()

	return nil
}