Convert a Ruby code into PHP function.

Convert a Ruby code into a PHP function. OpenStreetMaps is an open source mapping service that accepts URLs in two formats: 1)permalink [login to view URL] 2)Shortlink http://osm.org/go/0EEQjE== Details and specifications on Openstreetmaps and the Ruby code is available from ([login to view URL]) for encoding the shortlink. We require you to convert the this Ruby code into a PHP function for use within our web app. The intended use of this function is to generate shortlink URLs that will trigger a third party iPhone app called OpenMaps in the following format openmaps://go/0EEQjE== iOS or Apple app development skills are not required for this project. Ruby and PHP skills is a Must.