History question about June 1941 - PLEASE HELP

[Soviet]

Ok I have an obscured question to ask about the beginning of the war between the Nazi Germany and the Soviet Union. I just want to give you small background why I would like to ask such a question. I am a university student with German and Russian history. So I took 3 courses in the last 2 years about the Soviet Union history with 2 East European teachers (1 Russian and 1 Yugoslav, both specialists in Russian history). Both when they were talking about June 1941 said that Stalin never thought the German would attack, so that explains why the Soviets were so unprepared to the war against Germany. They said even thought that he didn’t want to believe the people who told him that the German could attack someday. So to sum up the position of my 2 teachers both teachers sustained that Stalin never thought the German would attack because it would have been too crazy for the German to fight on 2 Front.

After that, this year a have a Canadian teacher (he is a German specialist and not Russian this time) that denied this and says that Stalin knew that the German were to attack. He also says that is naïve to say that he didn’t know that. He said that explains why one week before the German attacked that the Soviets were doing military manoeuvres at the border to show their strength of power.

So finally, here is my question. Which thesis would you support and why: Did Stalin knew that the Germans would obviously attack the Soviet Union ?

What I think is that he somehow he knew they could attack but he didn’t believe in it. That would explain for me why Stalin disappear at is “dacha” for quite a long time after June 22nd 1941. I would more tend on the first thesis.

It’s somehow difficult for me to ask this question like this without speaking and only typing it. Hope you didn’t have any problem to understand my thoughts on that with my English.