Comparing smoking cessation pharmacotherapy: NRT vs varenicline vs bupropion — which to choose and when?

A 50-year-old male smoker (25 cigarettes/day for 30 years) wants to quit. He has mild depression and is currently on sertraline. He has tried NRT patches twice without success. How do we choose between varenicline, bupropion, and NRT combination in this patient? Are there any safety concerns with varenicline in patients on antidepressants or with psychiatric history?