How to make connection between a typescript file and a single file components in vue.js

i have a function in my single file components

function moveCircle(step: number) {
  if (activeCircle.value < 2) {
    activeCircle.value += step;
    activeLine.value += step;
  }
}

and i would like to make a signal to use this function in my index.ts (router)

        router.beforeEach((to, from, next) => {
            if (to.path > from.path) {
                console.log('forward');
                
            } else {
                console.log('back');
            }
            next();
        })

try to use a bus -> it,s not possible because to inject is use only on components try to call a function -> it's not possible to make this