A Maximum at One

Let $f(x) = a^2\ln x - \dfrac{1}{2}ax^2 - \left(a^2 - a\right)x$ with $a \neq 0$.

1. When $a = 1$, find the intervals on which $f(x)$ is monotonic. 2. If $f(x)$ attains a local maximum at $x = 1$, find the range of possible values of $a$.