Name This Tree

This is not an invasive species, although it originates from East Asia where it is known as “tea flower” and several species are used in the cultivation of tea leaves for beverage. The plant is evergreen, relatively short with a bushy shape, and has brightly colored flowers during the winter. Like other calcifuges known for their flowers, it prefers acidic soils. This is the state flower of Alabama. Do you know what tree this is?