The intestate share of the surviving spouse is as follows:
(1) As to separate property: If there is no surviving issue or parent of the decedent, the entire intestate estate;
(2) If there is no surviving issue but the decedent is survived by a parent or parents, one-half (½) of the intestate estate;
(3) If there are surviving issue of the deceased spouse, one-half (½) of the intestate estate.
(4) As to community property: The one-half (½) of community property which belongs to the decedent passes to the surviving spouse.