package client

import (
	"context"

	buffPool "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/api/util/pool"
	apistatus "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/client/status"
	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/object"
	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/object/transformer"
	"google.golang.org/grpc/codes"
	"google.golang.org/grpc/status"
)

func (c *Client) objectPutInitTransformer(prm PrmObjectPutInit) (*objectWriterTransformer, error) {
	var w objectWriterTransformer
	w.it = internalTarget{
		client: c,
		prm:    prm,
	}
	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.MaxSize,
		WithoutHomomorphicHash: prm.WithoutHomomorphHash,
		NetworkState:           prm.EpochSource,
		Pool:                   prm.Pool,
	})
	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
}

func (x *objectWriterTransformer) Close(ctx context.Context) (*ResObjectPut, error) {
	if x.err != nil {
		return nil, x.err
	}

	ai, err := x.ot.Close(ctx)
	if err != nil {
		return nil, err
	}

	if ai != nil {
		x.it.res.epoch = ai.Epoch
		if ai.ParentID != nil {
			x.it.res.obj = *ai.ParentID
		}
	}
	return x.it.res, nil
}

type internalTarget struct {
	client    *Client
	res       *ResObjectPut
	prm       PrmObjectPutInit
	useStream bool
}

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

func (it *internalTarget) putAsStream(ctx context.Context, o *object.Object) error {
	wrt, err := it.client.objectPutInitRaw(ctx, it.prm)
	if err != nil {
		return err
	}
	if wrt.WriteHeader(ctx, *o) {
		wrt.WritePayloadChunk(ctx, o.Payload())
	}
	it.res, err = wrt.Close(ctx)
	if err == nil && it.client.prm.DisableFrostFSErrorResolution && !apistatus.IsSuccessful(it.res.st) {
		err = apistatus.ErrFromStatus(it.res.st)
	}
	return err
}

func (it *internalTarget) tryPutSingle(ctx context.Context, o *object.Object) (bool, error) {
	if it.useStream {
		return false, nil
	}

	prm := PrmObjectPutSingle{
		XHeaders:     it.prm.XHeaders,
		BearerToken:  it.prm.BearerToken,
		Session:      it.prm.Session,
		Local:        it.prm.Local,
		CopiesNumber: it.prm.CopiesNumber,
		Object:       o,
		Key:          it.prm.Key,
	}

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

	if err == nil {
		it.returnBuffPool(o.Payload())
		id, _ := o.ID()
		it.res = &ResObjectPut{
			statusRes: res.statusRes,
			obj:       id,
			epoch:     res.epoch,
		}
		if it.client.prm.DisableFrostFSErrorResolution && !apistatus.IsSuccessful(it.res.st) {
			return true, apistatus.ErrFromStatus(it.res.st)
		}
		return true, nil
	}
	return true, err
}

func (it *internalTarget) returnBuffPool(playback []byte) {
	if it.prm.Pool == nil {
		return
	}
	var buffer buffPool.Buffer
	buffer.Data = playback
	it.prm.Pool.Put(&buffer)
}