China Mathematical Competition (Hainan)

Let $f$: $\mathbb{R}\to \mathbb{R}$ be a function such that $f(0)=1$ and for any $x$, $y\in \mathbb{R}$, $f(xy+1)=f(x)f(y)-f(y)-x+2$ holds. Then $f(x)=\underline{}$.