What mental disorder could it be?

We have tried to get him to seek help and get a diagnosis. But he refuses. So we don't exactly know what's going on. But, He talks to himself all day long, and also has conversations with people who aren't there. he will walk into an empty room and say "Hey how ya doing?" and proceed to have a conversation, answering questions, and everything. He really thinks he's talking to someone. He does this multiple times a day. He also goes through rapid emotional changes. He will be sad and cry for almost no reason, then laugh and giggle inappropriately at things. Almost child like. Then be aggressively and even violently angry, and then back to sad. This happens all in a matter of just a few mins. He also has no since of time. You can leave for 30 mins, He thinks it's been 5 hours. He also has hallucinations. He asked me for the remote to change the TV, he was angry and yelling at the screen saying, "get off the screen Dammit, he did this for a few mins, before asking for the remote". But... there's no TV at all in that room. He then he gets up, walks around, becomes confused, And then he will stumble and fall down almost as if his brain just stops sending signals to his body. Like he forgets how to stand or walk. He is also a diabetic, And drinks excessively. His daughter was diagnosed with Schizophrenia a few years ago. Could that be what this is? Is it hereditary? Do these symptoms match those of schizophrenia? What does it sound like to you?