I'd start counting calories, just to get an idea of where you actually are at. Just by looking at your list, I'd say maybe more protein, definitely more carbs, and more fat. What you are eating now is closer to cutting than adding muscle. You don't have to dramatically increase your calories suddenly, but obviously what you are eating now isn't enough even for maintence if you are losing fat.
If you don't like diving deep into counting calories and macronutrients, I'd just focus on getting at least 250g of protein in a day (at least more than 1g per pound of bodyweight) and slowly adding more food/calories into what you currently eat. More oatmeal, sweet potatoes are great, rice, etc are some good carb choices in to add in. As for fat, a little olive oil, beef fat, etc.
Just start slowly adding, and when you find your maintence range then you know to go from there and add some calories to build muscle.
I know this thread is about nutrition, but don't neglect your training either.