// Holds info about a given container image such as where to pull / push it to / from as well as the pull secret to use.
type ImageInfo struct {
    Pullspec       string
    PullSecretName string
}

// Holds the basic inputs needed to perform an OS image build.
type OSBuildInput struct {
    Dockerfile            string
    BaseImage             ImageInfo
    FinalImage            ImageInfo
    EntitlementSecretName string
}

type BuildStatus string

const (
    BuildStatusSuccess BuildStatus = "success"
    BuildStatusFailure BuildStatus = "failure"
    BuildStatusError   BuildStatus = "error"
)

// Holds info about the build status and outcome as well as a reference to the pod that is performing / performed the build.
type OSBuildStatus struct {
    Status       BuildStatus
    Err          error
    PodReference *metav1.ObjectReference
}

// The interface to implement
type MachineOSBuilderBackend interface {
    Build(*OSBuildInput) error
    Status() (*OSBuildStatus, error)
}

// A backend that uses OpenShift Builds
type OpenshiftBuildBackend struct{}func (o *OpenshiftBuildBackend) Build(i *OSBuildInput) error {
    // Implement me!
    return nil
}

func (o *OpenshiftBuildBackend) Status() (*OSBuildStatus, error) {
    // Implement me!
    return nil, nil
}

// A backend that uses custom Pods.
type CustomBuildBackend struct{}func (c *CustomBuildBackend) Build(i *OSBuildInput) error {
    // Implement me!
    return nil
}

func (c *CustomBuildBackend) Status() (*OSBuildStatus, error) {
    // Implement me!
    return nil, nil
}

// A backend that is optimized for single-node OpenShift
type SingleNodeBuildBackend struct{}func (s *SingleNodeBuildBackend) Build(i *OSBuildInput) error {
    // Implement me!
    return nil
}

func (s *SingleNodeBuildBackend) Status() (*OSBuildStatus, error) {
    // Implement me!
    return nil, nil
}

// A dynamic way to detect which backend should be used.
func GetBackend() MachineOSBuilderBackend {
    if isSNO() {
        return &SingleNodeBuildBackend{}
    }    if hasOpenshiftBuildCapability() {
        return &OpenshiftBuildBackend{}
    }    return &CustomBuildBackend{}
}