# What happens when light gets reflected and refracted at the same point?

Suppose that medium of refractive index n is placed on a mirror (as seen from the image), and the rest of the place is vacuum. A light ray is incident on the common point of vacuum, glass and mirror. What would be the path of light after reflection.

What seems sensible by symmetry to me is that refraction would take place as if light is coming from 'behind' the mirror. Thus, the angle between the mirror and refracted ray would be:\begin{align}\arcsin{(\frac{\sin\theta}{n})}\end{align} But I cannot justify this, nor am I certain about this.