Expand and reduce : normal

normal takes as argument a polynomial expression.
normal expand and reduce this expression in $\mathbb {Z}$/p$\mathbb {Z}$[x].
Input :

normal(((2*x^2+12)*( 5*x-4))%13)

Output :

(-3%13)*x^3+(5%13)*x^2+(-5%13)*x+4%13