Textarea for my web application

I am developing an application web based which would let the users extend a part of an applcation using javascript via java.scripting http://java.sun.com/javase/6/docs/technotes/guides/scripting/programmer_guide/index.html

The problem is that the user should write only some coditions and i want if possible to colour some special words and to check while typing if the variable that the user is typing exists.. Like a auto suggest thing... I searched at the web but didnt find many stuff. For WYSIWYG editors i couldnt determi开发者_如何学Cne if you can programaticcaly apply stuff and set/get caret position. Also i show that autosuggest is nearly impossible. It should be locatted outside of the textbox area.

I'd look into adapting ECCO into your project. I've not used it, but it looks amazing.