You read the light level once in setup(). I think you should be reading it more often than that.
You declared a variable called position but never used it.
You have an expression () directly following the else. Perhaps you meant to write another if() there? Then there's a semicolon after that so simply changing to "if" won't make any difference to the block {} of code that follows.
Add some hysteresis. Turn on when it's darker than 'dark' and turn off when lighter than 'sunny'. Make those two different numbers.