What is the ideal diet for a 16 year old male?

i currently eat around 1500 calories a day and i walk to school and back every day which is 2 miles and i walk around school a lot too, i am quite an active person and do cricket during the summer and i do 30 minutes of cardio on the wii most days so how many calories should i eat to maintain my weight, i am 16 5 ft 9/10 and currently weigh 46kg?