version

type Application interface {
	Version
	App() string
	Compatible(Application) error
	Before(Application) bool
}

type ApplicationParser interface {
	Parse(string) (Application, error)
}

type Compatibility interface {
	// Returns the local version
	Version() Application

	// Returns nil if the provided version is able to connect with the local
	// version. This means that the node will keep connections open with the
	// peer.
	Connectable(Application) error

	// Returns nil if the provided version is compatible with the local version.
	// This means that the version is connectable and that consensus messages
	// can be made to them.
	Compatible(Application) error

	// Returns nil if the provided version shouldn't be masked. This means that
	// the version is connectable but not compatible. The version is so old that
	// it should just be masked.
	Unmaskable(Application) error

	// Returns nil if the provided version will not be masked by this version.
	WontMask(Application) error

	// Returns when additional masking will occur.
	MaskTime() time.Time
}

type Parser interface {
	Parse(string) (Version, error)
}

type Version interface {
	fmt.Stringer

	Major() int
	Minor() int
	Patch() int
	// Compare returns a positive number if v > o, 0 if v == o, or a negative number if v < 0.
	Compare(o Version) int
}