Ajax chat for embedding in a website?

Question

JavaScript

I couldn't find it myself, so I'm asking for advice.

There is a website, php, CodeIgniter, VPS. There are users in the system.

It is necessary to fasten the chat with the following properties:
1. A strip appears at the bottom of the site, in which there is information about the number of users online, etc.
2. When you click something on the strip, the chat grows up by 200-300 pixels, preferably with the ability to change the height user.
3. Users are not able to change their nickname, it must be requested from our site (login or guest4118).
4. The server must be able to assign rooms to participants, but they themselves should not have such an opportunity. That is, everyone is sitting in a general chat, then something happened and 10 people ended up in a general
5. Ability to administer the chat, the appointment of moderators.
6. No java or flash applets. You can use IRC or someone else's service, you can load our server. No more than 1000 users at the same time.

Similar can be found on Facebook or Mail.ru, when there is a chat at the bottom right, but there is actually IM, chatting 1 on 1, and here you need a common room and separate ones.

It is clear that a lot will have to be finished, but I ask you to suggest something close.

Answer 1

Mel.chat, written in php using long polling. Author from habr, you can thank him.

Answer 2

Here meebo rooms is a pretty suitable thing, although half of the named ones are not there, only the video interferes with them a lot.

Answer 3

Try ajaxim.com/ (uses Node.js)