Imagine you are a healthcare professional and a 42-year-old male comes into your office complaining of headaches, thirst, and frequent urination. You perform a urinalysis and notice that his urine is abnormally dark and tests positive for glucose. Explain (from a physiological perspective) why he has glucose in his urine, why he is experiencing frequent urination, thirst, and headaches, and why his urine is abnormally dark.