package oci

import (
	"context"
	"fmt"

	"github.com/google/go-containerregistry/pkg/name"
	v1 "github.com/google/go-containerregistry/pkg/v1"
	"github.com/google/go-containerregistry/pkg/v1/remote"
)

type RegistryImageDetailsResolver struct {
	*ImageSpec
	descriptor *v1.Descriptor
}

func NewRegistryImageDetailsResolver(src *ImageSpec) (*RegistryImageDetailsResolver, error) {
	return &RegistryImageDetailsResolver{
		ImageSpec: src,
	}, nil
}

func (r *RegistryImageDetailsResolver) ImageName(_ context.Context) (string, error) {
	return r.Identifier, nil
}

func (r *RegistryImageDetailsResolver) ImagePlatform(_ context.Context) (*v1.Platform, error) {
	return r.Platform, nil
}

func (r *RegistryImageDetailsResolver) ImageDescriptor(ctx context.Context) (*v1.Descriptor, error) {
	if r.descriptor == nil {
		subjectRef, err := name.ParseReference(r.Identifier)
		if err != nil {
			return nil, fmt.Errorf("failed to parse reference: %w", err)
		}
		options := WithOptions(ctx, r.Platform)
		image, err := remote.Image(subjectRef, options...)
		if err != nil {
			return nil, fmt.Errorf("failed to get image manifest: %w", err)
		}
		digest, err := image.Digest()
		if err != nil {
			return nil, fmt.Errorf("failed to get image digest: %w", err)
		}
		size, err := image.Size()
		if err != nil {
			return nil, fmt.Errorf("failed to get image size: %w", err)
		}
		mediaType, err := image.MediaType()
		if err != nil {
			return nil, fmt.Errorf("failed to get image media type: %w", err)
		}
		r.descriptor = &v1.Descriptor{
			Digest:    digest,
			Size:      size,
			MediaType: mediaType,
		}
	}
	return r.descriptor, nil
}