I have the mean Doctor - LOL.
2 weeks pre-op is all liquid, high Protein. No more than 30 carbs per day and 600-800 calories per day. Which I am in the middle of right now. It isn't horrible. I'm not hungry. I just crave nutritional good for me food (no junk food cravings). Avoiding temptation is key -- at the office where I can't control the environment it is tough.
Post-surgery is all liquid for two weeks. Carb restriction is lifted, but target 90 grams of protein per day and 800-1000 calories.
Weeks 3-4 post surgery is just mushies.
Weeks 5 & 6 - gradually bring back "normal" food.