package pool

import (
	"context"

	sdkClient "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/client"
	apistatus "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/client/status"
	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/object"
	oid "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/object/id"
	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/object/transformer"
	"go.uber.org/zap"
	"go.uber.org/zap/zapcore"
	"google.golang.org/grpc/codes"
	"google.golang.org/grpc/status"
)

type logger interface {
	log(level zapcore.Level, msg string, fields ...zap.Field)
}

type PrmObjectPutClientCutInit struct {
	PrmObjectPut
}

func (c *clientWrapper) objectPutInitTransformer(prm PrmObjectPutClientCutInit) (*objectWriterTransformer, error) {
	cl, err := c.getClient()
	if err != nil {
		return nil, err
	}
	var w objectWriterTransformer

	w.it = internalTarget{
		client:  cl,
		prm:     prm,
		address: c.address(),
		logger:  &c.clientStatusMonitor,
	}

	key := &c.prm.key
	if prm.key != nil {
		key = prm.key
	}

	w.ot = transformer.NewPayloadSizeLimiter(transformer.Params{
		Key:                    key,
		NextTargetInit:         func() transformer.ObjectWriter { return &w.it },
		MaxSize:                prm.networkInfo.MaxObjectSize(),
		WithoutHomomorphicHash: prm.withoutHomomorphicHash,
		NetworkState:           prm.networkInfo,
		SessionToken:           prm.stoken,
	})
	return &w, nil
}

type objectWriterTransformer struct {
	ot  transformer.ChunkedObjectWriter
	it  internalTarget
	err error
}

func (x *objectWriterTransformer) WriteHeader(ctx context.Context, hdr object.Object) bool {
	x.err = x.ot.WriteHeader(ctx, &hdr)
	return x.err == nil
}

func (x *objectWriterTransformer) WritePayloadChunk(ctx context.Context, chunk []byte) bool {
	_, x.err = x.ot.Write(ctx, chunk)
	return x.err == nil
}

// ResObjectPut groups the final result values of ObjectPutInit operation.
type ResObjectPut struct {
	Status apistatus.Status
	OID    oid.ID
}

// Close return non nil result in any case. If error occurred, the result contains only buffer for further reusing.
func (x *objectWriterTransformer) Close(ctx context.Context) (*ResObjectPut, error) {
	ai, err := x.ot.Close(ctx)
	if err != nil {
		return nil, err
	}

	if ai != nil && ai.ParentID != nil {
		x.it.res.OID = *ai.ParentID
	}
	return &x.it.res, nil
}

type internalTarget struct {
	client               *sdkClient.Client
	res                  ResObjectPut
	prm                  PrmObjectPutClientCutInit
	useStream            bool
	address              string
	logger               logger
	resolveFrostFSErrors bool
}

func (it *internalTarget) WriteObject(ctx context.Context, o *object.Object) error {
	putSingleImplemented, err := it.tryPutSingle(ctx, o)
	if putSingleImplemented {
		return err
	}

	it.logger.log(zapcore.DebugLevel, "putSingle not implemented, trying put as stream", zap.String("address", it.address))

	it.useStream = true
	return it.putAsStream(ctx, o)
}

func (it *internalTarget) putAsStream(ctx context.Context, o *object.Object) error {
	cliPrm := sdkClient.PrmObjectPutInit{
		CopiesNumber: it.prm.copiesNumber,
		Session:      it.prm.stoken,
		Key:          it.prm.key,
		BearerToken:  it.prm.btoken,
	}

	wrt, err := it.client.ObjectPutInit(ctx, cliPrm)
	if err != nil {
		return err
	}
	if wrt.WriteHeader(ctx, *o) {
		wrt.WritePayloadChunk(ctx, o.Payload())
	}
	res, err := wrt.Close(ctx)
	if res != nil {
		it.res.Status = res.Status()
		it.res.OID = res.StoredObjectID()
	}
	return err
}

func (it *internalTarget) tryPutSingle(ctx context.Context, o *object.Object) (bool, error) {
	if it.useStream {
		return false, nil
	}
	cliPrm := sdkClient.PrmObjectPutSingle{
		CopiesNumber: it.prm.copiesNumber,
		Key:          it.prm.key,
		Session:      it.prm.stoken,
		BearerToken:  it.prm.btoken,
		Object:       o,
	}

	res, err := it.client.ObjectPutSingle(ctx, cliPrm)
	if err != nil && status.Code(err) == codes.Unimplemented {
		return false, err
	}

	if err == nil {
		id, _ := o.ID()
		it.res = ResObjectPut{
			Status: res.Status(),
			OID:    id,
		}
		if !it.resolveFrostFSErrors && !apistatus.IsSuccessful(it.res.Status) {
			return true, apistatus.ErrFromStatus(it.res.Status)
		}
		return true, nil
	}
	return true, err
}