fix(numbering): keep order and bill numbers unique across resets

docs/architecture/data-and-migrations.md

@@ -112,6 +112,20 @@ After migrations and with `foreign_keys` re-enabled, startup runs:
   non-daily reset periods are tracked dynamically.
 - `autoRepairPaymentDetails` and `autoRepairDefaultPrinter` - the two targeted data repairs.
 
+## Order and bill numbers
+
+`generateOrderNumber` and `generateBillNumber` in `main/db.ts` draw from the `sequences` table
+(`name`, `date` bucket) and format `[prefix-][date-or-period-]NNNN`. `orders.order_number` and
+`bills.bill_number` are `UNIQUE`, so two rules keep every number issuable:
+
+- A series that resets (daily orders; daily, monthly, or financial-year bills) always carries its
+  date or period, whatever the include toggle says; only a non-resetting series may omit it. The
+  `PUT /api/settings/order-numbering` route stores the effective flag, and `GET` reports it, so the
+  settings screen shows the include toggle only for a non-resetting series.
+- A candidate that is already issued (a mid-day setting change, a reused prefix, restored or
+  imported rows) lifts the counter past the highest number issued under the same head instead of
+  failing the sale. The allocation throws only if three attempts cannot find a free number.
+
 ## Backup and restore
 
 | Operation | Entry point | Notes |

frontend/src/app/(dashboard)/settings/page.tsx

@@ -3649,7 +3649,14 @@ export default function SettingsPage() {
         invoice_financial_year_start_month: orderNumberForm.invoiceFinancialYearStartMonth,
         invoice_financial_year_start_day: orderNumberForm.invoiceFinancialYearStartDay,
       });
-      const saved = { ...orderNumberForm, prefix, invoicePrefix };
+      const saved = {
+        ...orderNumberForm,
+        prefix,
+        invoicePrefix,
+        includeDate: orderNumberForm.includeDate || orderNumberForm.resetDaily,
+        invoiceIncludePeriod:
+          orderNumberForm.invoiceIncludePeriod || orderNumberForm.invoiceResetPeriod !== 'never',
+      };
       setOrderNumberForm(saved);
       setSavedOrderNumberForm(saved);
       if (!silent) toast.success(t('orderNumberingSaved'));

frontend/src/components/settings/GeneralSettingsTab.tsx

@@ -637,7 +637,7 @@ export function GeneralSettingsTab({
               <Ltr>
                 {[
                   orderNumberForm.prefix,
-                  orderNumberForm.includeDate ? sampleOrderDate : '',
+                  orderNumberForm.includeDate || orderNumberForm.resetDaily ? sampleOrderDate : '',
                   '0001',
                 ]
                   .filter(Boolean)
@@ -648,24 +648,26 @@ export function GeneralSettingsTab({
         </div>
 
         <div className="mt-5 pt-5 border-t border-border space-y-3">
-          <div className="flex items-center justify-between py-2">
-            <div>
-              <span className="text-sm text-foreground">{t('orderNumberIncludeDate')}</span>
-              <p className="text-xs text-muted-foreground">{t('orderNumberIncludeDateHint')}</p>
+          {!orderNumberForm.resetDaily && (
+            <div className="flex items-center justify-between py-2">
+              <div>
+                <span className="text-sm text-foreground">{t('orderNumberIncludeDate')}</span>
+                <p className="text-xs text-muted-foreground">{t('orderNumberIncludeDateHint')}</p>
+              </div>
+              <Toggle
+                value={orderNumberForm.includeDate}
+                label={t('orderNumberIncludeDate')}
+                onChange={
+                  isAdmin
+                    ? (v) => {
+                        markHydrationTouched('includeDate');
+                        setOrderNumberForm((p) => ({ ...p, includeDate: v }));
+                      }
+                    : () => {}
+                }
+              />
             </div>
-            <Toggle
-              value={orderNumberForm.includeDate}
-              label={t('orderNumberIncludeDate')}
-              onChange={
-                isAdmin
-                  ? (v) => {
-                      markHydrationTouched('includeDate');
-                      setOrderNumberForm((p) => ({ ...p, includeDate: v }));
-                    }
-                  : () => {}
-              }
-            />
-          </div>
+          )}
           <div className="flex items-center justify-between py-2">
             <div>
               <span className="text-sm text-foreground">{t('orderNumberResetDaily')}</span>
@@ -722,7 +724,8 @@ export function GeneralSettingsTab({
                 <Ltr>
                   {[
                     orderNumberForm.invoicePrefix,
-                    orderNumberForm.invoiceIncludePeriod
+                    orderNumberForm.invoiceIncludePeriod ||
+                    orderNumberForm.invoiceResetPeriod !== 'never'
                       ? invoicePreviewSegment(
                           orderNumberForm.invoiceResetPeriod,
                           orderNumberForm.invoiceFinancialYearStartMonth,
@@ -809,28 +812,30 @@ export function GeneralSettingsTab({
             )}
           </div>
 
-          <div className="mt-5 pt-5 border-t border-border">
-            <div className="flex items-center justify-between py-2">
-              <div>
-                <span className="text-sm text-foreground">{t('invoiceNumberIncludePeriod')}</span>
-                <p className="text-xs text-muted-foreground">
-                  {t('invoiceNumberIncludePeriodHint')}
-                </p>
+          {orderNumberForm.invoiceResetPeriod === 'never' && (
+            <div className="mt-5 pt-5 border-t border-border">
+              <div className="flex items-center justify-between py-2">
+                <div>
+                  <span className="text-sm text-foreground">{t('invoiceNumberIncludePeriod')}</span>
+                  <p className="text-xs text-muted-foreground">
+                    {t('invoiceNumberIncludePeriodHint')}
+                  </p>
+                </div>
+                <Toggle
+                  value={orderNumberForm.invoiceIncludePeriod}
+                  label={t('invoiceNumberIncludePeriod')}
+                  onChange={
+                    isAdmin
+                      ? (v) => {
+                          markHydrationTouched('invoiceIncludePeriod');
+                          setOrderNumberForm((p) => ({ ...p, invoiceIncludePeriod: v }));
+                        }
+                      : () => {}
+                  }
+                />
               </div>
-              <Toggle
-                value={orderNumberForm.invoiceIncludePeriod}
-                label={t('invoiceNumberIncludePeriod')}
-                onChange={
-                  isAdmin
-                    ? (v) => {
-                        markHydrationTouched('invoiceIncludePeriod');
-                        setOrderNumberForm((p) => ({ ...p, invoiceIncludePeriod: v }));
-                      }
-                    : () => {}
-                }
-              />
             </div>
-          </div>
+          )}
         </div>
       </div>
 

main/db.ts

@@ -8752,29 +8752,90 @@ function requireTenantTimezone(): string {
   }).timezone;
 }
 
+/** A series that restarts every day repeats its counter, so the date is what keeps each number unique. */
+export function orderNumberIncludesDate(includeDate: boolean, resetDaily: boolean): boolean {
+  return includeDate || resetDaily;
+}
+
+/** A series that restarts every period repeats its counter, so the period is what keeps each number unique. */
+export function invoiceNumberIncludesPeriod(includePeriod: boolean, resetPeriod: string): boolean {
+  return includePeriod || resetPeriod !== 'never';
+}
+
+// Longer suffixes are foreign numbers; lifting the counter to them could exhaust its integer range.
+const MAX_COUNTER_DIGITS = 9;
+
+/**
+ * Draws the next counter value for `bucket` and formats it as `<head>NNNN`. A candidate that is
+ * already issued (settings changed mid-day, a reused prefix, restored or imported rows) lifts the
+ * counter past the highest number issued under the same head instead of failing the sale.
+ */
+function allocateUniqueNumber(
+  sequence: string,
+  bucket: string,
+  table: 'orders' | 'bills',
+  column: 'order_number' | 'bill_number',
+  headParts: string[],
+): string {
+  const head = headParts.length ? `${headParts.join('-')}-` : '';
+  const isIssued = db.prepare(`SELECT 1 FROM ${table} WHERE ${column} = ?`);
+  const highestIssued = db.prepare(`
+    SELECT MAX(CAST(substr(${column}, ?) AS INTEGER)) AS highest
+    FROM ${table}
+    WHERE ${column} GLOB ? AND substr(${column}, ?) NOT GLOB '*[^0-9]*'
+      AND length(${column}) - ? <= ${MAX_COUNTER_DIGITS}
+  `);
+  const liftCounter = db.prepare(
+    'UPDATE sequences SET current_value = MAX(current_value, ?) WHERE name = ? AND date = ?',
+  );
+
+  for (let attempt = 0; attempt < 3; attempt++) {
+    const candidate = head + String(getNextSequence(sequence, bucket)).padStart(4, '0');
+    if (!isIssued.get(candidate)) return candidate;
+    const row = highestIssued.get(
+      head.length + 1,
+      `${head}[0-9]*`,
+      head.length + 1,
+      head.length,
+    ) as { highest: number | null } | undefined;
+    liftCounter.run(row?.highest ?? 0, sequence, bucket);
+  }
+  throw new Error(`Could not allocate a unique ${column}`);
+}
+
 export function generateOrderNumber(): string {
   const prefix = sanitizedNumberPrefix(getSettingValue('order_number_prefix'), 'ORD');
-  const includeDate = getSettingValue('order_number_include_date') !== 'false';
   const resetDaily = getSettingValue('order_number_reset_daily') !== 'false';
+  const includeDate = orderNumberIncludesDate(
+    getSettingValue('order_number_include_date') !== 'false',
+    resetDaily,
+  );
   const timezone = requireTenantTimezone();
 
   // Per-day bucket when reset daily, otherwise a single bucket.
-  const bucket = resetDaily ? dateStampInTimezone(timezone) : 'ALL';
-  const next = getNextSequence('orders', bucket);
-
-  const dateSegment = includeDate ? dateStampInTimezone(timezone) : '';
-  return [prefix, dateSegment, String(next).padStart(4, '0')].filter(Boolean).join('-');
+  const dateStamp = dateStampInTimezone(timezone);
+  const bucket = resetDaily ? dateStamp : 'ALL';
+  return allocateUniqueNumber(
+    'orders',
+    bucket,
+    'orders',
+    'order_number',
+    [prefix, includeDate ? dateStamp : ''].filter(Boolean),
+  );
 }
 
 export function generateBillNumber(): string {
   const prefix = sanitizedNumberPrefix(getSettingValue('invoice_number_prefix'), 'INV');
-  const includePeriod = getSettingValue('invoice_number_include_period') !== 'false';
   const configuredPeriod = getSettingValue('invoice_number_reset_period') || 'daily';
   const resetPeriod: InvoiceResetPeriod = ['never', 'daily', 'monthly', 'financial_year'].includes(
     configuredPeriod,
   )
     ? (configuredPeriod as InvoiceResetPeriod)
     : 'daily';
+  const includePeriod = invoiceNumberIncludesPeriod(
+    getSettingValue('invoice_number_include_period') !== 'false',
+    resetPeriod,
+  );
   const timezone = requireTenantTimezone();
   const fyStart = clampFinancialYearStart(
     getSettingValue('invoice_financial_year_start_month'),
@@ -8787,10 +8848,13 @@ export function generateBillNumber(): string {
     fyStart.day,
   );
   const bucket = resetPeriod === 'never' ? 'ALL' : periodSegment;
-  const next = getNextSequence('bills', bucket);
-  return [prefix, includePeriod ? periodSegment : '', String(next).padStart(4, '0')]
-    .filter(Boolean)
-    .join('-');
+  return allocateUniqueNumber(
+    'bills',
+    bucket,
+    'bills',
+    'bill_number',
+    [prefix, includePeriod ? periodSegment : ''].filter(Boolean),
+  );
 }
 
 export function now(): string {

main/routes/settings.ts

@@ -1,7 +1,14 @@
 import { Router, Request, Response, RequestHandler } from 'express';
 import expressRateLimit from 'express-rate-limit';
 import { randomUUID } from 'crypto';
-import { getDatabase, getSettingValue, now, parseBackupPaginationQuery } from '../db';
+import {
+  getDatabase,
+  getSettingValue,
+  invoiceNumberIncludesPeriod,
+  now,
+  orderNumberIncludesDate,
+  parseBackupPaginationQuery,
+} from '../db';
 import {
   CloudRequestError,
   cloudSync,
@@ -874,18 +881,26 @@ router.delete(
 
 // ─── Order numbering settings (must come BEFORE /:key wildcard) ─────────────
 
+const INVOICE_RESET_PERIODS = new Set(['never', 'daily', 'monthly', 'financial_year']);
+
 function orderNumberingShape(s: Record<string, string>) {
+  const resetPeriod = INVOICE_RESET_PERIODS.has(s.invoice_number_reset_period)
+    ? s.invoice_number_reset_period
+    : 'daily';
+  const orderResetDaily = s.order_number_reset_daily !== 'false';
   return {
     order_number_prefix: s.order_number_prefix ?? 'ORD',
-    order_number_include_date: s.order_number_include_date !== 'false',
-    order_number_reset_daily: s.order_number_reset_daily !== 'false',
+    order_number_include_date: orderNumberIncludesDate(
+      s.order_number_include_date !== 'false',
+      orderResetDaily,
+    ),
+    order_number_reset_daily: orderResetDaily,
     invoice_number_prefix: s.invoice_number_prefix ?? 'INV',
-    invoice_number_include_period: s.invoice_number_include_period !== 'false',
-    invoice_number_reset_period: ['never', 'daily', 'monthly', 'financial_year'].includes(
-      s.invoice_number_reset_period,
-    )
-      ? s.invoice_number_reset_period
-      : 'daily',
+    invoice_number_include_period: invoiceNumberIncludesPeriod(
+      s.invoice_number_include_period !== 'false',
+      resetPeriod,
+    ),
+    invoice_number_reset_period: resetPeriod,
     invoice_financial_year_start_month: parseBoundedInt(
       s.invoice_financial_year_start_month,
       1,
@@ -898,7 +913,6 @@ function orderNumberingShape(s: Record<string, string>) {
 
 // Alphanumeric only to avoid collisions with automatic hyphen separators.
 const ORDER_NUMBER_PREFIX_PATTERN = /^[A-Za-z0-9]{0,12}$/;
-const INVOICE_RESET_PERIODS = new Set(['never', 'daily', 'monthly', 'financial_year']);
 
 function parseBoundedInt(value: unknown, min: number, max: number, fallback: number): number {
   const parsed = typeof value === 'number' ? value : Number.parseInt(String(value ?? ''), 10);
@@ -979,16 +993,25 @@ router.put(
       }
 
       const db = getDatabase();
-      upsertSettings(db, {
-        order_number_prefix,
-        order_number_include_date: boolFlag(order_number_include_date),
-        order_number_reset_daily: boolFlag(order_number_reset_daily),
-        invoice_number_prefix,
-        invoice_number_include_period: boolFlag(invoice_number_include_period),
-        invoice_number_reset_period,
-        invoice_financial_year_start_month,
-        invoice_financial_year_start_day,
-      });
+      db.transaction(() => {
+        upsertSettings(db, {
+          order_number_prefix,
+          order_number_include_date: boolFlag(order_number_include_date),
+          order_number_reset_daily: boolFlag(order_number_reset_daily),
+          invoice_number_prefix,
+          invoice_number_include_period: boolFlag(invoice_number_include_period),
+          invoice_number_reset_period,
+          invoice_financial_year_start_month,
+          invoice_financial_year_start_day,
+        });
+        // Persist the effective flags so a series that must carry its date or period never
+        // stores a contradictory "off" that would resurface when the reset option changes.
+        const effective = orderNumberingShape(getAllSettings(db));
+        upsertSettings(db, {
+          order_number_include_date: String(effective.order_number_include_date),
+          invoice_number_include_period: String(effective.invoice_number_include_period),
+        });
+      })();
       res.json(orderNumberingShape(getAllSettings(db)));
     } catch (error: any) {
       console.error('[API] Internal error:', error);