Invoice States

Implemented invoice statuses and billing lifecycle transitions.

Invoice States

In a nutshell

Invoice status tracks where an invoice is in the collection lifecycle.

Invoice statuses

Status	Meaning
draft	Prepared before the due date.
open	Due and ready for collection.
paid	Fully paid.
failed	Payment failed.
refunded	Reserved for refund workflows.

Payment attempt statuses

Status	Meaning
PENDING_BILLING	A payment attempt has been created.
SUCCESS	Payment succeeded.
PAYMENT_FAILED	Payment failed.
REFUND	Reserved for refund workflows.
CANCELLED	Reserved for cancelled attempts.

Lifecycle

draft -> open -> paid
open -> failed