If a cop asks me if I want to buy drugs and I say yes, they most definitely have no case whatsoever here in Denmark even though I were willing to buy. Luckily we don't have these insane laws that cause police to get people in a bad place and then punish them for it.
That is also exactly how it works in the US. Intention and action, both are required.
If a cop asks you if you want to buy drugs, you say yes, he pulls out a baggie of white powder he claims is an 8-ball and then you hand over a wad of cash you are going to jail as soon as you accept the baggie in exchange for the cash. It was not a crime until you paid for the 'drugs'. The cop is giving you the opportunity to commit the crime, but the choice to do so is entirely made by you. That is not entrapment.
The key factor in most cases is if the actions of the police officer would have coerced a normally law-abiding citizen into breaking the law. An easy test for entrapment (but by no means a conclusive one) is if you swap out the cop with a criminal would the same transaction have occurred -- if you are ready to buy drugs from the cop it is likely that you would have bought them from a street dealer as well. Who was on the other side of the transaction didn't matter to you.
USA, circa 1993: I was in a car with a couple friends going to a neighborhood simply called "Temple", where meth labs were prevalent and you could procure any sort of drugs you wanted, if you knew where to park. Cops were everywhere and they stopped us, as we tried to turn around. "What are you white kids doing in Temple?" Before our driver could answer, a friend stuck his body between the front seats and yelled "we are here to buy drugs but you guys fucked it up!" - The cop did not laugh, but they let us go on our way.