package containerd

import (
	"context"

	imagesapi "github.com/containerd/containerd/api/services/images/v1"
	"github.com/containerd/containerd/api/types"
	"github.com/containerd/containerd/errdefs"
	"github.com/containerd/containerd/images"
	ptypes "github.com/gogo/protobuf/types"
	ocispec "github.com/opencontainers/image-spec/specs-go/v1"
)

type remoteImages struct {
	client imagesapi.ImagesClient
}

// NewImageStoreFromClient returns a new image store client
func NewImageStoreFromClient(client imagesapi.ImagesClient) images.Store {
	return &remoteImages{
		client: client,
	}
}

func (s *remoteImages) Get(ctx context.Context, name string) (images.Image, error) {
	resp, err := s.client.Get(ctx, &imagesapi.GetImageRequest{
		Name: name,
	})
	if err != nil {
		return images.Image{}, errdefs.FromGRPC(err)
	}

	return imageFromProto(resp.Image), nil
}

func (s *remoteImages) List(ctx context.Context, filters ...string) ([]images.Image, error) {
	resp, err := s.client.List(ctx, &imagesapi.ListImagesRequest{
		Filters: filters,
	})
	if err != nil {
		return nil, errdefs.FromGRPC(err)
	}

	return imagesFromProto(resp.Images), nil
}

func (s *remoteImages) Create(ctx context.Context, image images.Image) (images.Image, error) {
	created, err := s.client.Create(ctx, &imagesapi.CreateImageRequest{
		Image: imageToProto(&image),
	})
	if err != nil {
		return images.Image{}, errdefs.FromGRPC(err)
	}

	return imageFromProto(&created.Image), nil
}

func (s *remoteImages) Update(ctx context.Context, image images.Image, fieldpaths ...string) (images.Image, error) {
	var updateMask *ptypes.FieldMask
	if len(fieldpaths) > 0 {
		updateMask = &ptypes.FieldMask{
			Paths: fieldpaths,
		}
	}

	updated, err := s.client.Update(ctx, &imagesapi.UpdateImageRequest{
		Image:      imageToProto(&image),
		UpdateMask: updateMask,
	})
	if err != nil {
		return images.Image{}, errdefs.FromGRPC(err)
	}

	return imageFromProto(&updated.Image), nil
}

func (s *remoteImages) Delete(ctx context.Context, name string) error {
	_, err := s.client.Delete(ctx, &imagesapi.DeleteImageRequest{
		Name: name,
	})

	return errdefs.FromGRPC(err)
}

func imageToProto(image *images.Image) imagesapi.Image {
	return imagesapi.Image{
		Name:      image.Name,
		Labels:    image.Labels,
		Target:    descToProto(&image.Target),
		CreatedAt: image.CreatedAt,
		UpdatedAt: image.UpdatedAt,
	}
}

func imageFromProto(imagepb *imagesapi.Image) images.Image {
	return images.Image{
		Name:      imagepb.Name,
		Labels:    imagepb.Labels,
		Target:    descFromProto(&imagepb.Target),
		CreatedAt: imagepb.CreatedAt,
		UpdatedAt: imagepb.UpdatedAt,
	}
}

func imagesFromProto(imagespb []imagesapi.Image) []images.Image {
	var images []images.Image

	for _, image := range imagespb {
		images = append(images, imageFromProto(&image))
	}

	return images
}

func descFromProto(desc *types.Descriptor) ocispec.Descriptor {
	return ocispec.Descriptor{
		MediaType: desc.MediaType,
		Size:      desc.Size_,
		Digest:    desc.Digest,
	}
}

func descToProto(desc *ocispec.Descriptor) types.Descriptor {
	return types.Descriptor{
		MediaType: desc.MediaType,
		Size_:     desc.Size,
		Digest:    desc.Digest,
	}
}