What is the test for finding a statute facially unconstitutional?

"A statute is not facially unconstitutional simply because it may not be constitutionally applied to some persons or circumstances; at a minimum its unlawful application must be substantial and real when judged in relation to the statute's plainly legitimate sweep. Unless it is in total conflict with the Constitution, any overbreadth is cured by a case-by-case analysis of the particular fact situation. [Citation.] A statute will be declared invalid in its entirety only when its scope cannot be limited to constitutionally applicable situations except by reading in numerous qualifications and exceptions, i.e., rewriting it, or if it is invalid in certain situations and cannot be enforced in others without danger of an uncertain or vague future application." (Mounts v. Uyeda, supra, 227 Cal.App.3d at p. 122, 277 Cal.Rptr. 730.)