const (
	// DefaultKubeComponent is the component name for k8s control plane components.
	DefaultKubeComponent = "kube"
)

type ComponentGlobals struct {
	// contains filtered or unexported fields
}

type ComponentGlobalsRegistry interface {
	// EffectiveVersionFor returns the EffectiveVersion registered under the component.
	// Returns nil if the component is not registered.
	EffectiveVersionFor(component string) EffectiveVersion
	// FeatureGateFor returns the FeatureGate registered under the component.
	// Returns nil if the component is not registered.
	FeatureGateFor(component string) featuregate.FeatureGate
	// Register registers the EffectiveVersion and FeatureGate for a component.
	// returns error if the component is already registered.
	Register(component string, effectiveVersion MutableEffectiveVersion, featureGate featuregate.MutableVersionedFeatureGate) error
	// ComponentGlobalsOrRegister would return the registered global variables for the component if it already exists in the registry.
	// Otherwise, the provided variables would be registered under the component, and the same variables would be returned.
	ComponentGlobalsOrRegister(component string, effectiveVersion MutableEffectiveVersion, featureGate featuregate.MutableVersionedFeatureGate) (MutableEffectiveVersion, featuregate.MutableVersionedFeatureGate)
	// AddFlags adds flags of "--emulated-version" and "--feature-gates"
	AddFlags(fs *pflag.FlagSet)
	// Set sets the flags for all global variables for all components registered.
	// A component's feature gate and effective version would not be updated until Set() is called.
	Set() error
	// SetFallback calls Set() if it has never been called.
	SetFallback() error
	// Validate calls the Validate() function for all the global variables for all components registered.
	Validate() []error
	// Reset removes all stored ComponentGlobals, configurations, and version mappings.
	Reset()
	// SetEmulationVersionMapping sets the mapping from the emulation version of one component
	// to the emulation version of another component.
	// Once set, the emulation version of the toComponent will be determined by the emulation version of the fromComponent,
	// and cannot be set from cmd flags anymore.
	// For a given component, its emulation version can only depend on one other component, no multiple dependency is allowed.
	SetEmulationVersionMapping(fromComponent, toComponent string, f VersionMapping) error
}

type EffectiveVersion interface {
	// BinaryVersion is the binary version of a component. Tied to a particular binary release.
	BinaryVersion() *version.Version
	// EmulationVersion is the version a component emulate its capabilities (APIs, features, ...) of.
	// If EmulationVersion is set to be different from BinaryVersion, the component will emulate the behavior of this version instead of the underlying binary version.
	EmulationVersion() *version.Version
	// MinCompatibilityVersion is the minimum version a component is compatible with (in terms of storage versions, validation rules, ...).
	MinCompatibilityVersion() *version.Version
	EqualTo(other EffectiveVersion) bool
	String() string
	Validate() []error
	// AllowedEmulationVersionRange returns the string of the allowed range of emulation version.
	// Used only for docs/help.
	AllowedEmulationVersionRange() string
	// AllowedMinCompatibilityVersionRange returns the string of the allowed range of min compatibility version.
	// Used only for docs/help.
	AllowedMinCompatibilityVersionRange() string

	// Info returns the version information of a component.
	Info() *apimachineryversion.Info
}

type MutableEffectiveVersion interface {
	EffectiveVersion
	SetEmulationVersion(emulationVersion *version.Version)
	SetMinCompatibilityVersion(minCompatibilityVersion *version.Version)
}

type VersionMapping func(from *version.Version) *version.Version