Function parsePaysafeWebhookEvent

Parses a Paysafe webhook delivery into a UnifiedWebhookEvent. Call it only after verifyPaysafeWebhookSignature accepted the same raw body.

The envelope is read where Paysafe documents it: top-level payload, eventName, resourceId and eventDate, or the same fields nested under variables, as the Bacs page shows them. The older eventType/event name fields are still read; the top-level type is the resource category ("PAYMENT"), never the event name.

pspPaymentId names a payment and nothing else:

• a bank return (type "PAYMENT_RETURN", or a PAYMENT_RETURN… / PAYMENT_RETURNED… event) reports the returned payment from payload.paymentId, never the return's own payload.id;
• other payment events report payload.id, else resourceId;
• refund events report the refund as refundId and no pspPaymentId, since the refund payload names no payment;
• handle, settlement and every other resource leave it unset (correlate those by the payload merchantRefNum on raw).

amount is left out when the payload's currency is one the adapter refuses (see PaysafeServerAdapter), whose Paysafe minor units may not be PayFanout's; currency and every other field are reported as for any currency. A payload that states no currency, as Paysafe does not promise one on card refunds, keeps its amount as delivered.

id survives Paysafe's redeliveries. Paysafe sends no event id and repeats a notification with the next attemptNumber ("1", "2", "3"), so a hash of the raw bytes would give every attempt its own id. The id is paysafe_ + the SHA-256 hex of the JSON array [name, resourceId, status, time]: the normalized event name, the resource id (payload.id, else resourceId), the payload status, and the payload statusTime, else its txnTime, else the envelope eventDate. Distinct notifications agreeing on all four share an id (Paysafe's card and refund webhook examples carry no statusTime), so a host that must see every transition re-reads with retrievePayment / retrieveRefund whether or not the id was seen — except a bank return, which no documented read reflects: act on the return event itself. A top-level id is ignored — Paysafe's webhook page shows the resource's own id there — and a body naming no resource hashes its key-sorted JSON without attemptNumber.