I was texting a friend earlier and I tried speaking Japanese with her (utterly failing) and she sent "ばーーーか". I understand that this word means "fool; stupid", but I'm confused about the usage of dashes.
P.S.: I'm not learning Japanese at the moment so I have no idea about the usage of dashes in the language, or the entirety of the Japanese language in general. She's a native speaker and I attempted to converse with her with my trusty translator. Should I see this statement as offensive or should I simply take it as a joke? And what do those dashes mean in the context of this text?