Zac Efron covers the new issue of The Hollywood Reporter, and the 26-year-old star chats about his new movie, Neighbors, but most of the interview is spent talking about his recent personal struggles, specifically with substance abuse.

Efron opens up about his fight with a homeless man in downtown Los Angeles, and he says, "I was drinking a lot, way too much," acknowledging that there were drugs, too. "It's never one specific thing. I mean, you're in your 20s, single, going through life in Hollywood, you know? Everything is thrown at you."

So what's Zac's interpretation of events?
    "I had a friend come pick me up late at nightwe were looking for a place downtown to get a bite and catch up," he says. "We were having trouble finding somewhere...and the car ran out of gas off the 110. It was ridiculous. We had to pull over, and I called Uber [car service]. A homeless guy, or vagrant, tapped on the driver's-side window. Before I knew it, [my friend] was out of the car, and they started fighting. I saw that [the homeless man] was carrying some sort of a knife, or shank, and I got out of the car to disarm him. At some point, he dropped the knife, and I got hit pretty hard in the faceand almost instantly the police were there to break up the fight."

Though he had reportedly gone to rehab twice last year, he clearly wasn't taking his sobriety seriously, but he insists he is now. Zac says he's joined Alcoholics Anonymous and added that he's been seeing a therapist. "I just started going," he says. "And I think it's changed my life. I'm much more comfortable in my own skin. Things are so much easier now." Still, "it's a never-ending struggle."

"It's impossible to lead an honest and fulfilling life as a man and not make mistakes and 'fess up to them when you need to," he says. "But it's especially humiliating when they happen to be so public and so scrutinized ... At the same time, I'm a human being, and I've made a lot of mistakes. I've learned from each one."

So what is Zac doing these days to stay on track? He says he exercises daily (obviously!), eats healthy and goes to bed by 9pm. "I sit here in front of you today much happier and healthier than I've probably ever been," he concluded.

Let's hope it stays that way!