What is the test for determining the best interest of a parent in a custody dispute?

In an initial custody determination, such as here, the trial court has the "widest discretion to choose a parenting plan that is in the best interest of the child." ( 3040, subd. (b); In re Marriage of Burgess (1996) 13 Cal.4th 25, 31-32 (Burgess); Ragghanti v. Reyes (2004) 123 Cal.App.4th 989, 996 [trial court used correct "best interest" analysis where parties stipulated there was no existing final permanent custody order].) Section 3011 lists specific factors that the trial court must consider in determining the child's best interest: (a) the health, safety, and welfare of the child; (b) any history of abuse by one parent against the child or against the other parent; (c) the nature and amount of contact with both parents; and (d) the habitual or continual illegal use of controlled substances, or the habitual or continual abuse of alcohol. ( 3011, subd. (a); see also Burgess, supra, 13 Cal.4th at pp. 31-32.)