I. The court may, in its discretion, order a presentence investigation for a defendant convicted of a felony or a misdemeanor; provided that, upon the recommendation of the prosecution, the court shall order a presentence investigation report where the felony or misdemeanor was violent and the court has reason to believe that the defendant committed a similar act within the past year. The report shall include a recommendation as to disposition, together with reference to such material disclosed by the investigation as supports such recommendation.
II. Before imposing sentence, the court shall take such steps as may be necessary so that the defendant is advised, by counsel or otherwise, as the situation warrants, of the factual contents of any presentence investigation, and afforded a fair opportunity to contest them. The sources of confidential information need not, however, be disclosed.