It is hard with crazy hours. Protein and high fiber will keep you fuller longer than any other foods. You could bring a cooler of planned snacks like yogurt, cheese sticks, apples, veggies and hummus, small salad with chicken or tuna, etc. As a guy, you could probably eat more than 1200 calories and still lose. You could also try zig zagging your calories. If your working and on your feet you will burn off a lot of food.