# Codebase Audit — boha-app-ts — 2026-06-12

## Summary

| Severity     | Count |
| ------------ | ----: |
| **Critical** |     3 |
| **High**     |     6 |
| **Medium**   |    11 |
| **Low**      |     8 |
| **Total**    |    28 |

> 2026-06-12: M3 (offer PDF footer) withdrawn as a false positive after user
> verification — see the struck section below. Counts updated 12→11 / 29→28.

## Methodology

- **Fan-out discovery:** 27 independent finder passes swept the codebase across domain modules (auth/sessions, attendance/leave, documents — offers/orders/issued-orders/invoices, warehouse, projects, trips/vehicles, plan, users/roles, AI/Odin, settings) and cross-cutting dimensions (Zod-cap-vs-DB-column alignment, date/timezone boundaries, pagination determinism, React Query cache invalidation, transaction atomicity, FK-error→4xx mapping, privilege boundaries).
- **Dedupe vs prior backlog:** candidate findings were de-duplicated against the existing audit backlog (`docs/codebase-audit-findings-2026-06-06.md`, `docs/cross-module-consistency-audit-2026-06-09.md`, `REVIEW_FINDINGS.md`). Already-fixed items (e.g. the 2026-06-06 sessions audit-logging finding) and already-tracked duplicates were dropped; only net-new defects survived.
- **3-lens adversarial verification:** every surviving finding was independently re-checked through three lenses — (1) **trace-to-refute** (follow the full code path end-to-end and try to break each step), (2) **convention veto** (confirm it genuinely VIOLATES a documented `CLAUDE.md` convention and is NOT one of the deliberate "looks-like-a-bug" decisions: local-time `toJSON`, local-noon `@db.Date` writes, lenient date schemas, net-only documents, gross `received_invoices.amount`, shared `orders.*` permission family), and (3) **executable repro** (a concrete, developer-runnable reproduction with observable wrong output). A finding ships only with three independent `real` verdicts. Findings the convention lens vetoed (e.g. one warehouse over-issue variant whose exact numbers are blocked by an upstream aggregate guard — kept only after a corrected, reachable repro was supplied) were re-scoped, not waved through.

Order below is by severity, then by blast radius within a severity.

---

## CRITICAL

### C1. Deleting a vacation/sick attendance record never restores the leave balance — `vacation_used` stays permanently inflated

- **Severity:** Critical
- **File:** `src/services/attendance.service.ts:1751`
- **Failure scenario:** `createLeave` increments `leave_balances.vacation_used`/`sick_used` when booking leave (lines 1304–1331), but `deleteAttendance` (1751–1772) only runs `prisma.attendance.delete` — it never decrements the balance. `getStatus` (line 246) and `getBalances` (line 530) derive `vacation_remaining = vacation_total - vacation_used` from the stored counter, so cancelling a booked leave by deleting its rows permanently removes entitlement the employee never actually took. The leave-request approval path (`leave-requests.ts`) has the identical asymmetric increment-on-approve / no-decrement-on-delete.
- **Repro:**
  1. As an admin (`attendance.manage`), `POST /api/admin/attendance?action=leave` for user 5, `date_from=2026-07-06`, `date_to=2026-07-10`, `leave_type=vacation`, `leave_hours=8` → creates 5 rows and adds 40h to `vacation_used`.
  2. Read balances: `vacation_used=40`, `vacation_remaining = total-40`.
  3. `DELETE /api/admin/attendance/:id` for each of the 5 rows.
  4. Read balances again: rows are gone but `vacation_used` is still 40 and `vacation_remaining` is still down 40h. Only a manual admin `handleBalances` reset fixes it.
- **Pinning test:** Book a 5-day vacation, assert `vacation_used` rose by 40h, delete all 5 attendance rows, then assert `vacation_used` returned to its pre-booking value (fails today: stays 40).

### C2. `confirmIssue`: duplicate issue lines on the same batch pass per-line validation but decrement cumulatively, driving batch quantity negative (silent over-issue)

- **Severity:** Critical
- **File:** `src/services/warehouse.service.ts:626`
- **Failure scenario:** The confirm path validates and decrements stock **per line**, re-reading the batch fresh each iteration with no cross-line running tally and no `if (newBatchQty < 0) throw` guard. Two issue lines for the same item that resolve to the same batch each pass the independent `batch.quantity >= line.quantity` check, then the decrement loop accumulates: line A leaves the batch at 3, line B re-reads 3 and writes `3-5 = -2`, flagging `is_consumed=true`. The negative/consumed batch drops out of `getItemTotalStock` (`is_consumed:false` filter), so the over-issue is silently hidden from all stock totals. No `(issue_id, batch_id)` unique constraint exists on `sklad_issue_lines`.
- **Repro (corrected — the single-batch case is blocked by the per-item aggregate guard in `validateIssueReservationRules`; use two batches so the per-item total check passes while one batch still goes negative):**
  1. Seed item X with two unconsumed batches B1(qty 8, older) and B2(qty 8). Total stock = 16.
  2. `POST /issues` with two lines, both `item_id=X`, no `batch_id`, each `quantity=5`. `selectFifoBatches` is called once per line against the live DB with nothing persisted, so both resolve to B1; the per-item availability check (16 < 10 is false) passes. Draft stores two lines both `batch_id=B1`.
  3. `POST /issues/:id/confirm` → 200. B1 validated 8≥5 twice (both see original 8), then decremented to 3, then to `-2` with `is_consumed=true`.
  4. 10 units issued from a batch that held 8; B1 persists at `quantity=-2`, drops from stock totals — 2 units leave with no accounting trail and FIFO is broken, with no error raised.
- **Pinning test:** Confirm an issue containing two same-item lines whose combined quantity exceeds a single resolved batch; assert the confirm is rejected (400) and no batch row is left with `quantity < 0`.

### C3. `confirmInventorySession` swallows an in-transaction throw with `return` instead of `throw`, committing partial stock writes the route reports as failed

- **Severity:** Critical
- **File:** `src/services/warehouse.service.ts:1275`
- **Failure scenario:** The function body is `return prisma.$transaction(async (tx) => { ... })` (line 1108). A single loop over `session.items` interleaves real writes with a throwing op: the surplus branch (diff>0) creates a corrective receipt, receipt line, batch, and upserts `sklad_item_locations`; a later deficit line makes `selectFifoBatches` throw. The catch at line 1275 **returns** `{ error, status: 400 }` from inside the transaction callback. In an interactive Prisma transaction, returning a value (rather than throwing) **commits** — so the surplus item's writes persist while the session→CONFIRMED update (line 1293) is skipped, leaving the session DRAFT. The route sees `"error" in result` and returns HTTP 400 ("nothing changed"). Re-confirming the still-DRAFT session re-runs the loop and re-creates the same surplus batch — repeatable phantom inventory and corrupted valuation on every retry.
- **Repro:**
  1. ItemA exists; ItemB has a location row `quantity=10` but fewer unconsumed batches (documented location/batch drift at lines 1244–1250 — also reproducible by consuming batches between session create and confirm).
  2. `POST /admin/inventory-sessions` with items ordered `[{ItemA surplus, actual_qty 5}, {ItemB deficit, actual_qty 0}]` (ItemA's line gets the lower id, processed first).
  3. `POST /admin/inventory-sessions/<id>/confirm` → HTTP 400 "Nedostatečné množství na skladě", BUT ItemA now has a permanent +5 corrective batch + bumped `item_location`, and the session is still DRAFT.
  4. Re-confirm → another +5 for ItemA, fails on ItemB again. Each retry adds +5 phantom stock while the API reports failure.
- **Pinning test:** Confirm an inventory session whose item list has a valid surplus line before an over-deficit line; assert the response is an error AND no `sklad_receipts`/`sklad_batches` rows were created (transaction rolled back) and the session is unchanged.

---

## HIGH

### H1. Terminating one session force-logs-out ALL of the user's sessions on the terminated device's next refresh

- **Severity:** High
- **File:** `src/services/auth.ts:280`
- **Failure scenario:** Session termination (`sessions.ts:94-97` DELETE `/:id`, `sessions.ts:124-131` action=all, `profile.ts:98-101` password-change) sets ONLY `replaced_at` (no `replaced_by_hash`, row not deleted). Legitimate rotation (`auth.ts:315-318`) sets BOTH. The reuse-detection condition at `auth.ts:280-282` is `storedToken.replaced_at || storedToken.replaced_by_hash`, evaluated BEFORE the expiry check at line 292 — so a manually-terminated token presented on a later refresh is misclassified as theft and runs `tx.refresh_tokens.deleteMany({ where: { user_id } })` (line 285), wiping every session for that user, including the laptop the user is actively on, plus a false "reuse detected" warning.
- **Repro:**
  1. Log in from two devices → Session A (laptop), Session B (phone), both `replaced_at=null`.
  2. From the laptop, `DELETE /api/admin/sessions/<B.id>` → B gets `replaced_at` set only.
  3. After B's access token expires (~15 min), the phone calls `POST /api/admin/refresh` with B's still-present cookie.
  4. `refreshAccessToken` hits the reuse branch (B's `replaced_at` truthy), deletes ALL of the user's tokens including A. Laptop is silently logged out on its next refresh.
- **Pinning test:** Create two refresh-token sessions, terminate one via the sessions DELETE route, present the terminated token to `refreshAccessToken`; assert the OTHER session's row still exists (fails today: it is deleted).

### H2. `order_items.description` Zod cap (8000) far exceeds DB column `VarChar(500)` → Prisma 500 on long descriptions

- **Severity:** High
- **File:** `src/schemas/orders.schema.ts:12`
- **Failure scenario:** `OrderItemSchema.description = z.string().max(8000)` but `order_items.description` is `@db.VarChar(500)` (`schema.prisma:327`). `createOrder`/`updateOrder` map the value straight into `tx.order_items.createMany` with no truncation. A 501–8000 char description passes Zod, overflows the column under MySQL strict mode (P2000), and `createOrder`'s catch only re-maps errors carrying a `status` property — so it surfaces as HTTP 500 "Interní chyba serveru" instead of a clean Czech 400, with the whole order transaction rolled back.
- **Repro:** `POST /api/admin/orders` (Content-Type application/json so the manual-JSON branch runs), `items:[{ description: "x".repeat(600), quantity:1, unit_price:100 }]` → HTTP 500 instead of 400; no order persisted. Same on `PUT /api/admin/orders/:id` for an order in `prijata`/`v_realizaci`.
- **Pinning test:** `parseBody(OrderItemSchema, { description: "x".repeat(600), ... })` should fail Zod with a 400-class error (fails today: passes, then 500s at Prisma). Fix: `.max(500)`.

### H3. Issued-order status transition silently discards unsaved item/section edits and marks them clean

- **Severity:** High
- **File:** `src/admin/pages/IssuedOrderDetail.tsx:524`
- **Failure scenario:** A `sent` issued order is both editable AND has valid transitions. `handleStatusChange` (line 516) sends ONLY `{ status: newStatus }`; the server's `replaceItems = editable && Array.isArray(body.items)` is false for a status-only payload, so edited items/sections are never persisted. Worse, line 524 calls `markClean({ form, items, sections })` with the in-memory UNSAVED edits, re-baselining the unsaved-changes guard so `isDirty` flips false and the `beforeunload` warning never fires. After the transition the order is `confirmed` → read-only, so the lost edits cannot be re-applied. (Contrast: `OfferDetail`/`InvoiceDetail` do NOT call `markClean` on transition.)
- **Repro:** Open a `sent` issued order with `orders.edit`, edit a line item / section / supplier (form dirty), click "Potvrdit" and confirm. The transition succeeds, the edits are silently dropped, and on refetch the items/sections revert to stored values with no warning.
- **Pinning test:** Render `IssuedOrderDetail` for a `sent` order, mutate an item, invoke a status transition; assert the PUT payload includes the edited `items` (or that the guard stays dirty / a warning is shown) — fails today.

### H4. Received-invoices list is paginated server-side (25/page) but the UI sends no `page` param and renders no Pagination control — rows 26+ are permanently hidden

- **Severity:** High
- **File:** `src/admin/pages/ReceivedInvoices.tsx:265`
- **Failure scenario:** `receivedInvoiceListOptions` hits `/received-invoices`, which applies `skip`/`take` with `parsePagination`'s default limit of 25. The component builds the query with no `page`/`perPage`, reads only `listQuery.data?.data` (the first 25 rows), and renders NO `<Pagination>`. The "Celkem" footer is sourced from the separate `/received-invoices/list-totals` over the FULL filtered set, so with 26+ rows the displayed total visibly disagrees with the on-screen rows. The sibling issued-invoices tab (`Invoices.tsx`) correctly uses `usePaginatedQuery` + `<Pagination>`.
- **Repro:** Seed 26 CZK received invoices in one month. `GET /received-invoices?month=6&year=2026` returns `data.length=25`, `pagination.total=26`; `GET /received-invoices/list-totals?...` returns 26000 CZK. In the UI (Faktury → Přijaté, June 2026) the table shows 25 rows summing to 25000 while the footer shows 26000 — and the 26th invoice is unreachable.
- **Pinning test:** With 26 received invoices in a month, assert the page requests page 2 (or renders a pager) and that all 26 are reachable — fails today.

### H5. Odin invoice import: Czech-format dates silently corrupt month/year (wrong month or NaN) in `received_invoices`

- **Severity:** High
- **File:** `src/admin/components/odin/InvoiceReviewCard.tsx:79`
- **Failure scenario:** The review card exposes "Datum vystavení"/"Datum splatnosti" as free-text fields; `OdinChat.saveInvoice` sends the raw string. The multipart schema validates `issue_date` only as `z.string().max(255).nullish()`, so it passes. The route derives `invoiceMonth = new Date(issue_date).getMonth()+1` / `getFullYear()` with no validity guard. `new Date("15.03.2026")` → Invalid Date → `NaN` (day>12); `new Date("12.6.2026")` → December 2026 (wrong month). NAS save (line 410) runs BEFORE the DB create (line 420), so for the NaN case Prisma rejects into the `UnsignedTinyInt`/`UnsignedSmallInt` columns → HTTP 500 with an orphaned NAS file; for day≤12 it silently files under the wrong month/year.
- **Repro:** In Odin, edit an extracted invoice's issue date to `15.03.2026` and Save → 500 + orphaned NAS file. Use `12.6.2026` → invoice silently filed under month 12. Equivalent: `POST /api/admin/received-invoices` (multipart) with `issue_date:"15.03.2026"`.
- **Pinning test:** `POST /received-invoices` with `issue_date="15.03.2026"` should return a 400 (or normalize) — fails today (500 + NaN write). Fix: use `isoDateString` coercion / validity guard.

### H6. Leave-request approval charges vacation/sick balance for Czech public holidays that fall inside the range

- **Severity:** High
- **File:** `src/routes/admin/leave-requests.ts:222`
- **Failure scenario:** Both the request-creation loop (lines 90–97) and the approval loop (lines 222–244) count business days with a weekend-only filter (`dow !== 0 && dow !== 6`); the file never imports `isHoliday`. So weekday Czech public holidays inside the range are counted as charged leave days, and approval increments `vacation_used`/`sick_used` by `totalBusinessDays * 8` including them. The sibling `attendance.service.createLeave` (line 1270) correctly skips `isHoliday(...)`, and `getBusinessDaysInMonth` excludes holidays from the work fund — so the deduction is a double charge for a day already paid/free.
- **Repro:** Employee `POST /api/admin/leave-requests` `{leave_type:"vacation", date_from:"2026-05-01", date_to:"2026-05-09"}` (1.5. and 8.5. are weekday holidays in 2026) → `total_hours=48`. Approver `PUT /.../{id}` `{status:"approved"}` → `vacation_used` grows by 48h instead of 32h; holiday dates are recorded as consumed vacation in `attendance`.
- **Pinning test:** Approve a vacation request spanning a weekday public holiday; assert `vacation_used` increased only by the non-holiday business hours (fails today: includes the holiday).

---

## MEDIUM

### M1. Invoice date fields accept arbitrary strings and write a day early to `@db.Date` when a datetime value is submitted

- **Severity:** Medium
- **File:** `src/services/invoices.service.ts:533`
- **Failure scenario:** `CreateInvoiceSchema`/`UpdateInvoiceSchema` type `issue_date`/`due_date`/`tax_date`/`paid_date` as plain `z.string().max(255).nullish()` (not `isoDateString`). `createInvoice`/`updateInvoice` do `new Date(String(...))` straight into the `@db.Date` columns. A round-tripped API value like `"2025-03-15T00:00:00"` (the `toJSON` override emits local time, no `Z`) parses as local Prague → `2025-03-14 22:00 UTC` → Prisma truncates to `2025-03-14`. The invoice then also lands in the wrong month bucket in `getInvoiceStats`/`buildInvoiceWhere`. Every other `@db.Date`-writing module uses `isoDateString` (which slices the time off); invoices is the lone outlier.
- **Repro:** `POST /api/admin/invoices` with `issue_date:"2025-03-01T00:00:00"` → DB stores `2025-02-28`; `GET .../stats?month=3&year=2025` excludes it and inflates February.
- **Pinning test:** Create an invoice with `issue_date="2025-03-01T00:00:00"`; assert the stored date is `2025-03-01` (fails today: `2025-02-28`). Fix: `isoDateString.nullish()`.

### M2. `order_items.unit` Zod cap (255) exceeds DB column `VarChar(20)` → Prisma 500 on long unit strings

- **Severity:** Medium
- **File:** `src/schemas/orders.schema.ts:15`
- **Failure scenario:** `unit: z.string().max(255)` vs `order_items.unit @db.VarChar(20)` (`schema.prisma:330`). A 21–255 char unit passes Zod, overflows the column (P2000), and surfaces as 500 (the create catch only re-maps `status`-bearing errors; update has no try/catch). The sibling offers/issued-orders schemas correctly use `.max(20)`.
- **Repro:** `POST /api/admin/orders` (JSON) `items:[{ description:"Test", quantity:1, unit_price:100, unit:"abcdefghijklmnopqrstuvwxyz" }]` → HTTP 500 instead of 400. (The MUI form enforces `maxLength:20` client-side, so this is an API/non-browser vector.)
- **Pinning test:** `parseBody(OrderItemSchema, { unit: "x".repeat(21), ... })` should 400 at Zod — fails today. Fix: `.max(20)`.

### ~~M3. Offer PDF page footer ("Strana X z Y") never renders~~ — WITHDRAWN 2026-06-12 (false positive)

- **Status:** **Withdrawn** — user verified the footer DOES render in production.
- **Why the audit got it wrong:** the finding (and all three verification lenses) trusted the repo's own documentation — the `html-to-pdf.ts:68-74` comment and the CLAUDE.md line "Chromium has no CSS margin-box footers". That fact has been stale since **Chrome 131 (Nov 2024), which implemented CSS `@page` margin boxes**; the project runs Puppeteer 24.40 (bundled Chrome 146 locally) and prod renders with system Chromium 149, both far past 131, so the offer's `@bottom-center { counter(page) }` footer renders fine. No lens rendered an actual PDF — documentation poisoning, not a code bug.
- **Real follow-up (doc-only, Low):** correct the outdated claim in `html-to-pdf.ts` and CLAUDE.md so future work doesn't repeat this; the `footerTemplate` mechanism and the CSS margin-box mechanism are now BOTH valid, coexisting approaches.

### M4. `customer_order_number` Zod cap (255) exceeds DB column `VarChar(100)` → Prisma 500

- **Severity:** Medium
- **File:** `src/schemas/orders.schema.ts:54`
- **Failure scenario:** `customer_order_number: z.string().max(255)` vs `orders.customer_order_number @db.VarChar(100)` (`schema.prisma:356`). A 101–255 char value passes Zod, overflows the column (P2000 under strict mode), and surfaces as 500 instead of 400 (no P2003/P2000 mapping; create catch only handles `status`-bearing errors).
- **Repro:** `POST /api/admin/orders` (JSON) `{ customer_order_number: "A".repeat(150), currency:"CZK", language:"cs", status:"prijata" }` → HTTP 500; no order created. Same on `PUT /api/admin/orders/:id`.
- **Pinning test:** `parseBody(CreateOrderSchema, { customer_order_number: "A".repeat(150), ... })` should 400 — fails today. Fix: `.max(100)` on both schemas.

### M5. Foreign-currency invoice PDF returns HTTP 500 (and fails to archive) when the CNB rate lookup throws

- **Severity:** Medium
- **File:** `src/routes/admin/invoices-pdf.ts:411`
- **Failure scenario:** For a EUR invoice, `const cnbRate = isForeign ? await getRate(currency, issueDateStr) : 1.0` is unguarded. When CNB is unreachable and no cached entry exists for the issue date, `getRate` throws "Nepodařilo se získat aktuální kurzy z ČNB", which propagates to the route's catch and returns the 500 error page — blocking BOTH preview and NAS archival, even though the rate only feeds the cosmetic CZK-conversion footnote. Sibling consumers (`received-invoices` stats, `ai-tools`) wrap `toCzk` and degrade per-row; the PDF path has no fallback.
- **Repro:** EUR invoice with a back-dated/never-fetched issue date, CNB unreachable → `GET /api/admin/invoices-pdf/:id` (preview) or `?save=1` (archive) returns 500; the `save=1` archival is silently swallowed client-side, leaving no NAS copy.
- **Pinning test:** Mock `getRate` to throw, render a foreign-currency invoice PDF; assert a non-error response (PDF rendered with the conversion line omitted) — fails today (500).

### M6. `updateProject` sets FK fields with no existence check → FK violation 500

- **Severity:** Medium
- **File:** `src/services/projects.service.ts:115`
- **Failure scenario:** `updateProject` writes `customer_id`/`responsible_user_id`/`quotation_id`/`order_id` straight into `prisma.projects.update` with only int coercion and no `findUnique`. The FKs are `onDelete: Restrict`, so a non-existent id raises P2003 → generic 500. `createProject` validates `customer_id`/`responsible_user_id` and returns clean Czech 400s; the update path is the inconsistent gap.
- **Repro:** `PUT /api/admin/projects/1` `{ "customer_id": 999999 }` → HTTP 500 "Interní chyba serveru" instead of "Zákazník nenalezen" 400. Same for the other three FK fields.
- **Pinning test:** `PUT /projects/:id` with a non-existent `customer_id`; assert a 400 with a Czech "nenalezen" message — fails today (500). Fix: mirror `createProject`'s existence checks.

### M7. Date-range filters/reports exclude the whole `date_to` day (`lte` against UTC-midnight) — inclusive end date silently drops same-day records

- **Severity:** Medium
- **File:** `src/routes/admin/warehouse.ts:1038`
- **Failure scenario:** Receipts/issues filters and the project-consumption / movement-log reports build `created_at: { lte: new Date(date_to) }`. `new Date("2026-06-12")` parses as UTC midnight = 02:00 Prague; `created_at` is `@db.DateTime(0)` storing local-time instants, so a receipt at 09:00 Prague (07:00Z) is `> 00:00Z` and excluded. The entire requested end day disappears from filtered lists and report totals.
- **Repro:** Confirm a receipt today at 09:00 Prague. `GET /admin/warehouse/receipts?date_from=2026-06-12&date_to=2026-06-12` returns zero rows. Reports for a period ending 2026-06-12 under-report the last day.
- **Pinning test:** Create a same-day receipt at 09:00 local, filter `date_to` = that date; assert the receipt is returned — fails today. Fix: half-open `lt utcMidnightOfLocalDay(date_to + 1 day)`.

### M8. POST/PUT receipts & issues 500 on nonexistent or deleted FK ids instead of a clean Czech 400

- **Severity:** Medium
- **File:** `src/routes/admin/warehouse.ts:1117`
- **Failure scenario:** The receipts/issues create+update handlers write rows directly with no FK-existence pre-check and no try/catch; schemas only int-coerce ids. A deleted/nonexistent `supplier_id`/`location_id`/`item_id`/`project_id`/`batch_id` raises P2003/P2025 → generic 500. The document modules (offers/orders/issued-orders) and `trips.ts` all pre-validate FK existence precisely to avoid this; warehouse omits the guard.
- **Repro:** `POST /receipts` `{ items:[{ item_id: 99999999, quantity:1, unit_price:10 }] }` → 500. `POST /issues` `{ project_id: 99999999, items:[{ item_id:<in-stock>, quantity:1 }] }` → 500. `POST /issues` with a valid item + nonexistent explicit `batch_id` → 500.
- **Pinning test:** `POST /receipts` with a nonexistent `item_id`; assert a 400 ("Položka nenalezena") — fails today (500).

### M9. `updateEntry` never re-checks the per-cell cap, so expanding an entry's range pushes a day past `MAX_RECORDS_PER_CELL` and silently hides existing records

- **Severity:** Medium
- **File:** `src/services/plan.service.ts:597`
- **Failure scenario:** `createEntry`/`bulkCreateEntries`/`createOverride` all guard the per-cell cap of 3 via `assertEntryCapAvailable`, but `updateEntry` does not. Expanding an entry's `date_from`/`date_to` onto a day that already holds 3 active entries succeeds, producing 4. `resolveCell`/`resolveGrid` cap display at 3 (newest-first), so the oldest entry silently vanishes from the grid while remaining active in the DB.
- **Repro:** Create 3 active entries on 2099-07-01 for user 5; create a 4th on 2099-07-02; `PATCH /plan/entries/<4th>` `{ date_from:"2099-07-01", date_to:"2099-07-01" }` → 200; the grid for that day now shows only 3 of the 4 entries.
- **Pinning test:** Fill a day to the cap, then `PATCH` another entry to overlap that day; assert the update is rejected with the cap error — fails today.

### M10. `POST /users` does not strip `role_id` for non-admins — a `users.create` holder can grant any non-admin role

- **Severity:** Medium
- **File:** `src/routes/admin/users.ts:63`
- **Failure scenario:** The POST handler forwards `role_id` straight to `createUser`; `createUser` only rejects the literal `admin` role. The PUT handler explicitly strips `role_id`/`is_active` for non-admin callers ("Privilege-escalation guard"), so create is an inconsistent escalation surface: a `users.create` holder can mint an account on any high-privilege non-admin role (e.g. one bundling `settings.roles` or `users.edit`) the caller itself lacks. Violates the documented "Role-management writes are admin-only and re-checked" rule.
- **Repro:** As account M with only `users.create`, `POST /api/admin/users` `{ ..., role_id: N }` where N is a non-admin role bundling `settings.roles`/`users.edit` → 201; the new account holds permissions M never had.
- **Pinning test:** As a non-admin `users.create` caller, POST a user with a privileged `role_id`; assert the created user's role is NOT the privileged one (role stripped, as on PUT) — fails today.

### M11. `route_from`/`route_to` Zod cap (255) exceeds DB column `VarChar(100)` — 500 or silent truncation

- **Severity:** Medium
- **File:** `src/schemas/trips.schema.ts:17`
- **Failure scenario:** `route_from`/`route_to` cap at `.max(255)` (create lines 17–18, update 29–30) vs `trips.route_from/route_to @db.VarChar(100)` (`schema.prisma:668-669`). The route writes `String(body.route_from)` directly. A 101–255 char route passes Zod, then either 500s (P2000 strict mode, no global Prisma mapping) or silently truncates to 100 chars (data loss). The frontend TextFields have no `maxLength`, so the UI triggers it too.
- **Repro:** `POST /api/admin/trips` with a 150-char `route_from` → 500 (or truncated 201). Same on `PUT`.
- **Pinning test:** `parseBody(CreateTripSchema, { route_from: "x".repeat(101), ... })` should 400 — fails today. Fix: `.max(100)`.

### M12. Shared Puppeteer browser disconnecting mid-render fails concurrent PDF requests (no re-acquire/retry)

- **Severity:** Medium
- **File:** `src/utils/html-to-pdf.ts:92`
- **Failure scenario:** `getBrowser()` returns the cached module-level browser after a point-in-time `connected` check; `htmlToPdf` immediately does `b.newPage()` with no re-check. Two concurrent renders capture the same handle; if Chromium crashes (OOM/killed) after the guard, both reject. A's finally nulls the shared handle out from under B. Both return 500 even though an immediate retry would relaunch and succeed — there is no re-acquire/retry wrapper.
- **Repro:** Fire two simultaneous `GET /api/admin/orders-pdf/5` (always renders, no NAS short-circuit), then `pkill -9 chrome` during the render window → both requests 500; the next request succeeds.
- **Pinning test:** Stub the cached browser so `connected` is true at guard time and false at `newPage` time; assert `htmlToPdf` re-acquires and resolves (or both concurrent calls succeed on retry) — fails today.

---

## LOW

### L1. Client-supplied TOTP secret up to 255 chars overflows `VarChar(255)` after encryption, yielding a 500 instead of a 400

- **Severity:** Low
- **File:** `src/schemas/auth.schema.ts:30`
- **Failure scenario:** `TotpEnableSchema.secret` caps at `.max(255)` on the plaintext, but the stored value is the AES-256-GCM ciphertext (`base64(IV[12] + ciphertext + tag[16])`), which exceeds 255 chars for any plaintext over ~164 chars. `users.totp_secret` is `@db.VarChar(255)`. The pre-write `totp.validate` does not bound secret length, and the attacker controls both `secret` and `code`, so a long secret reaches the write → P2000 → 500 (strict mode) or silent ciphertext truncation that permanently locks the account out.
- **Repro:** Authenticated, 2FA-not-enabled user: generate a 250-char base32 secret + matching TOTP code, `POST /api/admin/totp/enable` with the correct password → 500 (or corrupted secret).
- **Pinning test:** Enable TOTP with a 250-char secret; assert a 400 (not 500) — fails today. Fix: `.max(64)` (real secrets are 16–32 chars).

### L2. Offer number sequence is never released on delete when created and finalized in different calendar years

- **Severity:** Low
- **File:** `src/services/offers.service.ts:522`
- **Failure scenario:** `generateOfferNumber` keys on `new Date().getFullYear()` (finalize year), assigning e.g. `2026/NA/001`. `deleteOffer` derives the release year from `existing.created_at.getFullYear()` (2025) and calls `releaseOfferNumber(2025, "2026/NA/001")`; `releaseSequence` reconstructs the highest as `2025/NA/<n>`, which never equals `2026/NA/001`, so the `deletedNumber === highestNumber` guard is false and the 2026 counter keeps a permanent gap. `invoices.service.ts` solves the same problem correctly by parsing the year out of the document number.
- **Repro:** Create a draft `2025-12-30`, finalize it `2026-01-02` → `2026/NA/001`. Delete it → next finalized 2026 offer is `2026/NA/002` (gap; no `2026/NA/001`).
- **Pinning test:** Create a draft in year Y, finalize+delete it in year Y+1; assert the Y+1 sequence counter was released — fails today. Fix: parse the year from the assigned number.

### L3. `customers` list paginates with non-unique sort columns and no `id` tiebreak → unstable pagination

- **Severity:** Low
- **File:** `src/routes/admin/customers.ts:54`
- **Failure scenario:** `orderBy: { [sortField]: order }` over allow-listed fields (`name`/`city`/`country`/`company_id`, all non-unique) with no `{ id }` tiebreak, used with offset pagination. Rows sharing a sort-key value that straddle a page boundary can reorder between the page-1 and page-2 queries, duplicating one and skipping another. Violates the documented determinism rule; siblings (`issued-orders.ts`, `trips.ts`) use compound `[..., { id }]` orderings. (The same defect exists at `received-invoices.ts:144`.)
- **Repro:** Seed customers with a shared `city` straddling a `limit=2` boundary; page through `?sort=city` and observe a customer appearing on two pages while another is skipped.
- **Pinning test:** Paginate a sort over duplicate-`city` customers; assert the concatenated pages contain every customer exactly once — fails today. Fix: `orderBy: [{ [sortField]: order }, { id: order }]`.

### L4. Invoice month navigation does not reset the page index → switching to a sparser month shows an empty table

- **Severity:** Low
- **File:** `src/admin/pages/Invoices.tsx:244`
- **Failure scenario:** `prevMonth`/`nextMonth` mutate `statsMonth`/`statsYear` but never `setPage(1)` (unlike the status/search handlers). The list query keys on `page` + month, and the server never clamps page to `total_pages`, so paging to page 3 of a busy month then switching to a 1-page month requests `?page=3&month=...` and gets an empty `data` array — empty table for a populated month, with the pager reading "3 of 1".
- **Repro:** Open a month with 60+ invoices, go to page 3, click the previous-month chevron to a month with a handful → empty "Zatím nejsou žádné faktury" table. API: `GET /api/admin/invoices?page=3&month=<sparse>&year=<y>` returns `data:[]` with non-zero `total`.
- **Pinning test (component):** With `page=3`, fire `nextMonth`; assert `page` resets to 1 — fails today.

### L5. Issued-orders sub-list keeps its page index when the parent Orders page changes month → empty list for sparser months

- **Severity:** Low
- **File:** `src/admin/pages/IssuedOrders.tsx:135`
- **Failure scenario:** `IssuedOrders` receives `month`/`year` as props and holds `page` in local state with no effect/key resetting it on prop change (the child is not keyed by month/year, so it doesn't remount). Paging to page 2 of a busy month then moving the parent to a sparse month requests page 2 of the new month → empty `data` → "Zatím žádné vydané objednávky." for a month that has orders on page 1.
- **Repro:** Objednávky → Vydané: navigate to a month with ≥26 issued orders, click page 2, then use the parent month chevron to a month with 1–25 orders → empty sub-list. API equivalent: `GET /api/admin/issued-orders?page=2&month=<1..25 orders>&year=<y>` → `data:[]` with non-zero `total`.
- **Pinning test (component):** With `page=2`, change the `month` prop; assert `page` resets to 1 (or is clamped to `total_pages`) — fails today.

### L6. Settings "System" tab save clobbers freshly-saved "Firma" numbering patterns with stale values

- **Severity:** Low
- **File:** `src/admin/pages/Settings.tsx:297`
- **Failure scenario:** Both tabs edit the same singleton `company_settings` row via `PUT /company-settings`. `sysForm` carries `offer_number_pattern`/`order_number_pattern`/`invoice_number_pattern` (populated once, gated by a never-reset `sysFormInitialized` flag). After editing numbering in the Firma tab (which invalidates `["company-settings"]`), `sysForm` stays stale; saving the System tab sends the whole stale form, and the backend applies every `!== undefined` field, silently reverting the Firma-tab change.
- **Repro:** Init the System tab; in the Firma tab change `offer_number_pattern` and save; return to System and save any unrelated field → `offer_number_pattern` reverts to its pre-edit value, with a success toast.
- **Pinning test:** PUT the offer pattern, then PUT a stale sysForm carrying the old pattern; assert the offer pattern is NOT reverted (or that System-tab saves omit the numbering fields) — fails today.

### L7. `start_km`/`end_km` accept decimals but DB columns are `Int` — non-integer odometer reading errors or truncates

- **Severity:** Low
- **File:** `src/schemas/trips.schema.ts:15`
- **Failure scenario:** `start_km`/`end_km` use `nonNegativeNumberFromForm` (only `Number.isFinite && >=0`, no integer refine), but the columns are `Int`. A decimal passes Zod, reaches the `Int` column → Prisma validation 500 or MySQL truncation (corrupting the reading and derived distance, propagated into `vehicles.actual_km`). Same mismatch for `vehicles.initial_km`/`actual_km`. The UI's `parseInt` is used only for the distance widget, not the submitted payload, so the browser is vulnerable too.
- **Repro:** `POST /api/admin/trips` `{ vehicle_id, trip_date:"2098-01-15", start_km:100.5, end_km:1200.7, route_from:"A", route_to:"B" }` → 500 (or truncated values).
- **Pinning test:** `parseBody(CreateTripSchema, { start_km: 100.5, ... })` should 400 — fails today. Fix: `nonNegativeIntFromForm` for the four km fields.

### L8. AI monthly budget control: severity-mismatched permission, date asymmetry, dead UI button, currency overflow, audit-log boundary (grouped low-severity cluster)

These five independently-confirmed low-severity findings share the "minor blast radius / narrow trigger" profile. Each is real and pinnable.

- **L8a. Company-wide AI monthly budget is mutable by any `ai.use` holder (not admin/settings).** `src/routes/admin/ai.ts:58`. `PUT /api/admin/ai/budget` is gated only by `requirePermission("ai.use")`, an ordinary grantable permission. Setting `budget_usd=0` makes `assertBudgetAvailable` return 402 for everyone (admins included) → company-wide AI DoS; setting `1000000` removes the cost cap. The parallel `company-settings` writes are gated behind `settings.company`/`settings.system`.
  - **Repro:** As any `ai.use` holder, `PUT /api/admin/ai/budget {"budget_usd":0}` → all `ai/chat` and `extract-invoices` calls 402.
  - **Pinning test:** Call `PUT /ai/budget` as a non-admin `ai.use`-only user; assert 403 — fails today. Fix: gate behind `settings.company`/admin.

- **L8b. Audit-log `date_from` filter boundary shifted ~2h vs `date_to` (UTC vs local parsing).** `src/routes/admin/audit-log.ts:46`. `from = new Date(date_from)` parses as UTC midnight (02:00 Prague), while `to = new Date(date_to + "T23:59:59")` parses as local — so events between 00:00 and 02:00 Prague on the from-date are silently excluded.
  - **Repro:** `GET /api/admin/audit-log?date_from=2026-06-12&date_to=2026-06-12` omits a row logged at 01:30 Prague that day.
  - **Pinning test:** Insert an audit row at 01:30 local, filter for that day; assert it's returned — fails today.

- **L8c. Draft invoice shows a non-functional "Zobrazit fakturu" PDF button that always errors.** `src/admin/pages/InvoiceDetail.tsx:1805`. The button render guard lacks the `status !== "draft"` check that `OfferDetail`/`IssuedOrderDetail` have; clicking it on a draft opens a blank tab, 404s `/file`, closes the tab, and toasts an error.
  - **Repro:** Open a draft invoice, click "Zobrazit fakturu" → blank tab flash + "PDF soubor nenalezen" toast.
  - **Pinning test:** Render `InvoiceDetail` for a draft; assert the PDF button is not rendered — fails today. Fix: add `&& invoice.invoice_number` (or non-draft) to the guard.

- **L8d. Odin "Měna" / received-invoice currency over 3 chars 500s the save (`VarChar(3)` vs schema `max(20)`).** `src/components/odin/InvoiceReviewCard.tsx:67` / `src/schemas/received-invoices.schema.ts:11`. A free-text currency like "Koruna" passes Zod (`max(20)`) but overflows `received_invoices.currency @db.VarChar(3)` (P2000 → 500), AND because the NAS write precedes the DB create, the uploaded file is orphaned. The same module's `description` (`max(8000)` vs `VarChar(500)`) and `invoice_number` (`max(255)` vs `VarChar(100)`) are also misaligned.
  - **Repro:** Save an Odin invoice with `currency:"Koruna"` → 500 + orphaned NAS file. Equivalent: `POST /received-invoices` multipart with `currency:"Koruna"`.
  - **Pinning test:** `parseBody(CreateReceivedInvoiceSchema, { currency:"Koruna", ... })` should 400 — fails today. Fix: `currency .max(3)`, `description .max(500)`, `invoice_number .max(100)`.

- **L8e. Warehouse supplier `ico`/`dic` Zod caps (255) exceed `VarChar(20)` columns.** `src/schemas/warehouse.schema.ts:34`. A >20-char `ico`/`dic` (bad paste) passes Zod and 500s at Prisma. Low realism (real IČO=8 digits) but a genuine 500-vs-400 defect; the customers schema (`company_id`/`vat_id`) shares it.
  - **Repro:** `POST /api/admin/warehouse/suppliers` `{ name:"Test", ico:"123456789012345678901" }` → 500.
  - **Pinning test:** `parseBody(CreateSupplierSchema, { ico:"x".repeat(21), ... })` should 400 — fails today. Fix: `.max(20)`.

> **Adjacent uncited Zod-cap mismatches confirmed during verification** (same bug class, fix alongside the above so the gap is closed once): invoice line-item `description` (`max(8000)` vs `VarChar(500)`) and `unit` (`max(255)` vs `VarChar(20)`) — `src/schemas/invoices.schema.ts:13,16`, **High** blast radius (whole invoice save rolls back); invoice bank/payment fields `payment_method`/`constant_symbol`/`bank_swift`/`bank_iban`/`bank_account` (caps 255 vs `VarChar(50)/VarChar(20)`) — `src/schemas/invoices.schema.ts:30-35`, **Medium**; warehouse `/items` list ignores the client `sort` param and sorts by non-unique `name` with no `id` tiebreak — `src/routes/admin/warehouse.ts:662`, **Low**; year-spanning leave request books all hours against the start year's balance only — `src/routes/admin/leave-requests.ts:195`, **Medium**; Dashboard "Přidat jízdu" quick action omits `["vehicles"]` invalidation — `src/admin/components/dashboard/DashQuickActions.tsx:184`, **Low**. These were verified `real` but fall outside the 29-item cited set; treat them as a fast-follow batch.

---

## Recommended Fix Order (dependencies considered)

**Phase 0 — Data-integrity criticals first (financial/stock corruption, silent & cumulative).** These corrupt persisted state and worsen on retry; fix before anything cosmetic.

1. **C3** `confirmInventorySession` `return`→`throw` (one-line change; stops repeatable phantom inventory). Trivial, highest leverage.
2. **C2** `confirmIssue` cross-line over-issue guard (add a running per-batch tally / up-front availability pass, mirroring the existing `confirmIssue` validation-first pattern; consider a `(issue_id, batch_id)` unique constraint as a backstop).
3. **C1** leave-balance restore on attendance delete — but **do C1 together with H6 and the year-spanning leave finding**, since all three live in the leave/attendance balance code and a single corrected helper (per-day, holiday-aware, per-year accumulation, with an inverse on delete) resolves them coherently. Fix the holiday-counting (H6) and per-year split first, then route delete through the same helper.

**Phase 1 — Security / privilege & session correctness.** 4. **H1** session-reuse misclassification (gate the reuse branch on `replaced_by_hash` alone; reorder vs the expiry check). Self-contained; high user impact. 5. **M10** `POST /users` role-strip for non-admins; **L8a** AI budget permission gate. Both are permission-boundary one-liners.

**Phase 2 — The Zod-cap-vs-DB-column batch (single coordinated sweep).** All of **H2, M2, M4, M11, L1, L8d, L8e** plus the adjacent invoice item/bank caps share one mechanism and one fix shape (`.max()` alignment + optionally a global P2000→400 mapping in `server.ts`). Do them in one pass with a shared "cap-must-fit-column" test helper so the class is closed, not whacked one at a time. Highest blast radius within the batch (whole-save rollback): invoice item caps, then H2.

> **Phase 2 follow-ups (2026-06-12, deliberately deferred):** (1) the optional
> global P2000→400 mapping in the `server.ts` error handler was NOT added —
> `server.ts` exports no app builder, so the mapping would be untestable
> without first extracting an exported `buildApp()`; do the refactor + backstop
> together. (2) Frontend `maxLength` attributes on the trips (odkud/kam) and
> invoice bank/payment form fields — pure UX polish now that Zod 400s
> over-length input with a Czech message; add when next touching those forms.

**Phase 3 — FK-existence & error-mapping consistency.** **M6** (projects update), **M8** (warehouse receipts/issues), **M5** (CNB graceful degradation). These align the lagging modules with the established offers/orders pre-validation pattern; a shared P2003→Czech-400 mapping (added in Phase 2 if you choose the global-handler route) reduces the per-site work.

**Phase 4 — Date/timezone boundaries.** **M1** (invoice date `isoDateString`), **M7** (warehouse `date_to` half-open), **H5** (Odin Czech-date), **L8b** (audit-log `from`). Group because they share the documented date-boundary helpers (`isoDateString`, `utcMidnightOfLocalDay`); fixing M1/H5 also removes a day-shift class.

**Phase 5 — Pagination determinism & frontend state.** **H4** (received-invoices pager — add the missing `usePaginatedQuery`/`<Pagination>`), **L3** (customers + received-invoices `id` tiebreak), **L4/L5** (page-reset on month change), **M9** (plan update cap), **H3** (issued-order transition flush edits + don't `markClean` stale state). H4 is the largest UI change; the rest are small, independent guards.

**Phase 6 — Cosmetic / low-blast cleanup (parallelizable, no dependencies).** ~~M3~~ (withdrawn; only the stale Chromium-footer comment in `html-to-pdf.ts`/CLAUDE.md remains as a doc fix), **M12** (Puppeteer re-acquire/retry), **L2** (offer number release year), **L6** (Settings System/Firma clobber), **L7** (km integer coercion), **L8c** (draft PDF button guard), warehouse `/items` sort param + tiebreak, and the Dashboard `["vehicles"]` invalidation.

Rationale for ordering: persisted-data corruption (Phase 0) cannot be allowed to accumulate; security boundaries (Phase 1) are cheap and high-impact; the cap batch (Phase 2) and FK/error mapping (Phase 3) are most efficient done as coordinated sweeps that share a fix shape and tests; date boundaries (Phase 4) share helpers; UI/pagination (Phase 5) depend on nothing earlier but benefit from the cleaner backend; everything in Phase 6 is independent and can be parallelized across contributors.
