Three StaffUser constants carried plaintext PINs (1234/2345/3456) in
auth_controller.dart. Every build shipped every till's credentials, readable
by anyone who unzipped the APK. Across 100 deployed devices that is one
credential, not a hundred.
- Schema v5 adds a staff table. Only a PBKDF2-HMAC-SHA256 hash and a per-user
random salt are stored; the PIN itself exists nowhere, including there.
12,000 iterations, tuned so one sign-in is imperceptible while working
through all 10,000 four-digit PINs against a stolen database takes ~15
minutes per account instead of milliseconds.
- Verification is constant-time. String == returns at the first differing
byte, and that timing leaks how much of a guess was right.
- StaffUser no longer has a pin field at all, so the credential cannot drift
back into memory, into widgets, or into a const declaration.
- Weak PINs are refused: under four digits, non-numeric, repeated digits, and
sequences. Two staff cannot share a PIN — the till identifies a cashier by
PIN alone, so a shared one would attribute bills to whichever row was
checked first.
- The last admin cannot be demoted or deactivated. A till with no admin cannot
be administered, including to appoint one, and recovering means editing the
database by hand.
- Staff are deactivated, never deleted, so bills already rung keep naming a
real person.
Seed accounts are now 4821/5093/6274 rather than 1234/2345/3456 — the weak-PIN
rule refuses the old ones, and a default the rule itself would reject is not a
defensible default. All three are flagged must-change-pin so they get a shop
trading on day one without becoming permanent.
Store details are now editable data, not compile-time constants. Name,
address, GSTIN and phone persist to the database and are read back rather than
falling through to the build's constants, which would silently undo a failed
save. GSTIN is format-validated including the state code — it prints on every
invoice as a legal requirement, so a typo is a compliance problem across
hundreds of bills before anyone notices.
Tests: 141 -> 160. Includes a test that reads every column of every staff row
and asserts no seed PIN appears anywhere in the database.
Migration test now asserts v5 and that an upgraded terminal comes up with the
staff table present but empty — seeding is the store's job on first open, so
an existing shop is never handed accounts it did not create.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Bills were persisted correctly but read back wrong. The read path rebuilt a
cart from its lines alone, dropping bill-level discounts and loyalty, so every
figure derived from a stored bill was overstated: the upload payload, the day
archive and the shift report. A discounted 529 bill read back as 620.
Money and data integrity
- order_dao: restore bill_discount and points_redeemed when rebuilding a cart;
keep the reconstruction tier-less so the membership discount is not applied
twice. Trust the recorded total and points via SaleTransaction.storedTotal.
- checkout_sale + order_dao.commitSale: write the bill, its stock movement and
the loyalty update in one transaction. Previously a failure part-way through
left a persisted bill the cashier believed had failed, inviting a duplicate.
- checkout_sale: re-check every line against live stock. A parked bill resumed
after its stock was sold passed validation and oversold.
- catalogue_dao: allocate the invoice sequence in one transaction; the previous
read-modify-write could hand two sales the same number and fail UNIQUE.
- local_store: replay unsynced sales after a catalogue import, so a mid-shift
re-import cannot restore stock that has already been sold.
- payment_controller: stamp the signed-in operator on the bill instead of the
hardcoded seed session, and pass the terminal id through.
- cart: reconcile per-slab GST against the bill total so the parts sum to the
whole on a tax invoice.
Sync and reporting
- sync_repository: drain unsynced bills in a loop rather than silently capping
at one page; stop on rejection so rejected rows cannot loop forever.
- sync_log_dao (new): persist the sync history to the sync_log table, which the
schema already defined but nothing used. It was in memory, so the only record
that bills had been uploaded died at restart.
- Scope shift reports by cashier. day_archive is re-keyed to
(business_date, cashier_name) so a till stays settleable after its bills are
uploaded and deleted. Schema v4 with a migration that carries v3 rows across.
Input and UI
- barcode_service: consume machine-paced keystrokes so a scan cannot also land
in the focused field, and raise the bar to 60ms/char while a text field has
focus so typing a mobile number is not read as a scan. Clock and focus check
injected so the behaviour is testable.
- primary_button: make the label flexible; label plus trailing total overflowed
the Charge button by up to 131px.
- app_router: redirect instead of null-casting when the receipt route is
entered without its transaction.
- customer_repository: reduce the search query to digits so a punctuated mobile
number matches.
Cleanup
- Remove TransactionRepository.save, CustomerRepository.recordSale and
OrderDao.insertOrder, all superseded by commitSale.
- dart fix across the tree; 251 analyzer issues down to 3 info-level.
Tests: 23 passing / 15 failing -> 90 passing. Fixed the two defects that broke
the existing suite (containsAll type argument, reset() needing a catalogue) and
deleted the leftover template test. Added coverage for the order round trip,
the day archive after a real sync, stock safety, checkout atomicity, the v3->v4
migration, scanner-versus-human input, and an app-level smoke test that renders
every module.
Note: bills already uploaded with a discount went up overstated. This stops it
happening again but does not correct historical server data.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
