/**
  * Handle an incoming request.
  *
  * @param  \Illuminate\Http\Request  $request
  * @param  \Closure  $next
  * @return mixed
  */
 public function handle($request, Closure $next)
 {
     if (!$this->auth->user()->is_admin) {
         // All activities that belongs to the centres that the authenticated user is in charge of
         $activitiesInCentres = collect(Activity::ofCentreForStaff($this->auth->user())->get()->lists('activity_id'));
         // Redirect user if activity accessed is not in list
         if (!$activitiesInCentres->contains($request->route()->parameter('activities'))) {
             return redirect('/activities');
         }
     }
     return $next($request);
 }