Add Funds or Reward Points in Customer Account

I intend to directly add reward points to customer account.

I will create new account for the customer and add reward points in their account. Facility to send Email to customer informing him about the reward points in his account. Customer can then buy on the site and redeem the reward points in his account. I should also be able to add more reward points to the existing customer account.

Is this built in feature of Opencart or is there any module which can do this?

I am new to Opencart so assistance is very much appreciated.

- Harish

Built in feature. Edit the customer in the Admin->Sales->Customer area and on the "Transaction" tab, you can add store credits