JS language definition

Hello!

You want to write a script to determine the users language.
Only js without php.

Thats the algorithm.

First visit:
The user visits the site (his language is determined).
Language is memorized in cookies
Redirect to the right section

Language Choice Selector:
When the language changes, the language in the cookies should be updated.

Re-visit:
A redirect is made to the desired section if there is a record in the cookies.