func MinAvailable(deployment *apps.Deployment) int32 {
	if !IsRollingUpdate(deployment) {
		return int32(0)
	}
	return *(deployment.Spec.Replicas) - MaxUnavailable(*deployment)
}

// MaxSurge returns the maximum surge pods a rolling deployment can take.
func MaxSurge(deployment apps.Deployment) int32 {
	if !IsRollingUpdate(&deployment) {
		return int32(0)
	}
	// Error caught by validation