How can I have a custom button on a page to modify its page title?

[Chengteng Li]

Hi,
So with ScriptRunner For Confluence, I have created a custom button on every page. I'd like to have a page title changed by clicking this button. More precisely, I need to append a special character (like "@") before the title on the first click, and if an "@" already exists, the clicking should replace it with "$".
Also, this "title change" should be saved into the database of Confluence. So I'm guessing I should use Groovy or send a web request in some way. I'm not familiar with programming. Any idea is much appreaciated!
Thanks in advance!