Subscription of products on AceShop (Joomla extension for OpenCart)
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I am trying to modify AceShop module (extension OpenCart in Joomla) such that subscription facility is provided to users on some specific products. The default functionality of AceShop is straightforward one-time order, but I want my shop to have some specific products that can be subscribed by the user as well. I know that payment gateways like Paypal and Authorize.net provide subscription facility, but I want my shop to keep track of those subscribed products, so that notification is sent to the subscribed users 5 days prior to their order that needs to be shipped and hence they could change the subscription details. 

In case of credit card charging gets failed, user is informed and if the subscription is still placed, system again tries to charge from the credit card after some defined period. Order completion invoice is sent each time the credit card gets charged, not for the first time only.

Out of confusion, I want to know if there is a way to do, and I am thinking in a right direction.