copy JS function from one php file to another

i have a dekstop file and a mobile file and i need to copy a JS function/code from the desktop file to the mobile file
i tried but its not working properly
the file structure is slightly different so requires delicate handling
i have the code/js but need to place it correctly in the file and handle any JS references/errors

i will show u exactly the code and u can help me to insert it

i need a call with u to discuss the job and u will fix in live time over a screen share
its a simple fast job for a skilled php/js coder.

no time wasters