Hulk Hogan can't be happy Ben Affleck and Matt Damon are doing a movie on what we're told is the "darkest period of his life," and if Ben and Matt cross the line, he's ready, willing and able to take legal action ... TMZ has learned.

B&M are producing a flick on the lawsuit the WWE legend filed and won against Gawker, after the site posted a sex tape video of Hogan and the wife of a friend. A racial epithet was captured on the vid. Hulk sued Gawker for invasion of privacy and in 2016 won a whopping $140 million verdict ... which eventually tanked Gawker.

Sources connected to Hulk tell TMZ he has no involvement whatsoever in the film project and is currently "indifferent" about it. HOWEVER, if the movie treads into territory that a jury already found was protected by his right to privacy, Hulk will not hesitate to pursue legal options ... which he's clearly done before.

Our sources say Hulk "is in a really good place in his life right now" ... he has a new wife, he's become spiritual and he's pursuing an exciting new business opportunity with his beer. He's also doing charitable work with a homeless shelter in Tampa, shelling out money to make life for residents more comfortable.