Fancy part title page with titleformat and centering problem

I would like to create a fancy part title page but I have some issues with titleformat. Currently, I use :

\titleformat{\part}[display]
{\normalfont\filcenter\thispagestyle{empty}}
{}{0pt}{
\LARGE\color{nicedarkblue}
\scshape\Huge\color{nicedarkblue}
\linebreak
#1
\linebreak
\LARGE\color{nicedarkblue}

• adds "Première partie\linebreak" (first part in french), "Deuxième partie\linebreak" (second part in french) in case of \partjust before the title of the part