[BackStacked]

Requested by Himanshu · project thread

This covers C1 and C2 from the handoff: a booking can be changed after it is made, and it can be billed in the same request that creates it.

updateBooking (booking:update)

A booking can be edited while it is booked, sample collected or in process.

• Doctor, collection type, time, address and notes. Fields left out stay as they are. null clears the doctor, the time or the address.
• Add tests. A new sample type gets a new pending tube.
• Remove tests. Only while the test has no results; its empty report is dropped.
  • A tube that hasn't been collected yet is dropped when no remaining test needs it.
  • The last test can't be removed. Cancel the booking instead.
• Billing follows, in the same transaction.

The invoice is	What happens	Extra permission
Unpaid	Cancelled and issued again with the booking's tests. Line discounts and the bill discount (capped) are kept.	invoice:create, plus invoice:cancel when tests are removed
Paid or credited	A credit note for each removed test's line. refundablePaise says what can be refunded.	accounts:post
Paid, and tests are added	A new invoice for the added tests	invoice:create

• Booking.invoice stays on the first live invoice. The new Booking.invoices lists every invoice of the booking, and cancelBooking now checks all of them.
• Every edit is audited as booking.update with what changed.

Front desk can add tests, but can't remove a billed test, because that needs invoice:cancel or accounts:post.

createBooking bill (C2)

bill: { payments, billDiscountPaise, applyTaxRules } issues the invoice for the booked tests inside the booking's transaction. A bad discount or payment leaves no booking behind. It needs invoice:create, plus invoice:discount for a discount and payment:create for payments, the same as issueInvoice.

Releases needed first

1. client 1.10.0 (feat: bookings.update, bill at booking, Booking.invoices (1.10.0) client#17). kits.json already points at it.
2. Then refresh the lockfile with npm install @mgpl-diagnostics/client@1.10.0. Until then, CI's check that every operation exists in the client fails on updateBooking.

No other kit changes: it uses db-kit 2.1.1 and finance-kit 1.0.1 as they are. Version 0.1.4. Tag v0.1.4 after merge; that release also carries #33.

Checks

• PostgreSQL: TEST_BACKENDS=pg npm test, with client 1.10.0 installed from its packed tarball, gives 260 passed, 0 failed. That includes 22 new end-to-end checks:
  • billing at booking, including rollback on a bad payment and the discount permission;
  • an unpaid invoice replaced;
  • a paid invoice credited, with a separate invoice for the added test;
  • the permission checks for front desk;
  • results locking a test in;
  • tenant isolation and the audit entries;
  • the trial balance still balancing.
• MongoDB: not run here, because this container can't download MongoDB. CI runs it.
• Typecheck passes. The schema, API reference and llms files are regenerated. docs/07-domain-flows.md and docs/examples/lab-day.graphql are updated.

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