feat: add math preferences (#710)

* feat(math): add MathSettings type and store defaults

* feat(math): add locale-aware formatting utilities with tests

* feat(math): integrate locale-aware formatting into math engine

Replace hardcoded 'en-US' locale and precision 6 in formatResult with
configurable activeLocale/activeDecimalPlaces backed by formatMathNumber
and formatMathDate utilities. Add setFormatSettings() to the engine API.
Update formatMathDate to include date+time (matching prior toLocaleString
behavior) and fix tests to use explicit en-US locale.

* feat(math): use locale-aware formatting for results total

* feat(math): wire math settings from store to workspace and results panel

* feat(math): add preferences page with i18n, routing, and navigation

* fix(math): apply locale formatting to unit results and exclude dates from total

Author: antonreshetov

src/main/i18n/locales/en_US/preferences.json

@@ -115,6 +115,17 @@
     "label": "Markdown",
     "codeRenderer": "Code block Renderer"
   },
+  "math": {
+    "label": "Math Notebook",
+    "locale": {
+      "label": "Region",
+      "description": "Number and date display format."
+    },
+    "decimalPlaces": {
+      "label": "Decimal Places",
+      "description": "Maximum decimal places in results (0\u201314)."
+    }
+  },
   "api": {
     "label": "API Port",
     "port": {

src/main/store/module/preferences.ts

@@ -1,6 +1,7 @@
 import type {
   EditorSettings,
   MarkdownSettings,
+  MathSettings,
   NotesEditorSettings,
   PreferencesStore,
 } from '../types'
@@ -20,6 +21,11 @@ const isWin = platform() === 'win32'
 
 const storagePath = isWin ? `${homedir()}\\massCode` : `${homedir()}/massCode`
 
+const MATH_DEFAULTS: MathSettings = {
+  locale: 'en-US',
+  decimalPlaces: 6,
+}
+
 const PREFERENCES_DEFAULTS: PreferencesStore = {
   appearance: {
     theme: 'auto',
@@ -41,6 +47,7 @@ const PREFERENCES_DEFAULTS: PreferencesStore = {
       scale: 1,
     },
   },
+  math: MATH_DEFAULTS,
 }
 
 function sanitizeCodeEditorSettings(value: unknown): EditorSettings {
@@ -143,6 +150,19 @@ function sanitizeMarkdownSettings(value: unknown): MarkdownSettings {
   }
 }
 
+function sanitizeMathSettings(value: unknown): MathSettings {
+  const source = asRecord(value)
+
+  return {
+    locale: readString(source, 'locale', MATH_DEFAULTS.locale),
+    decimalPlaces: readNumber(
+      source,
+      'decimalPlaces',
+      MATH_DEFAULTS.decimalPlaces,
+    ),
+  }
+}
+
 function sanitizePreferences(value: unknown): PreferencesStore {
   const source = asRecord(value)
   const appearanceSource = asRecord(source.appearance)
@@ -162,6 +182,7 @@ function sanitizePreferences(value: unknown): PreferencesStore {
     = Object.keys(asRecord(editorSource.markdown)).length > 0
       ? asRecord(editorSource.markdown)
       : asRecord(source.markdown)
+  const mathSource = asRecord(source.math)
 
   return {
     appearance: {
@@ -210,6 +231,7 @@ function sanitizePreferences(value: unknown): PreferencesStore {
       notes: sanitizeNotesEditorSettings(notesEditorSource),
       markdown: sanitizeMarkdownSettings(markdownSource),
     },
+    math: sanitizeMathSettings(mathSource),
   }
 }
 

src/main/store/types/index.ts

@@ -78,6 +78,11 @@ export interface NotesEditorSettings {
   indentSize: number
 }
 
+export interface MathSettings {
+  locale: string
+  decimalPlaces: number
+}
+
 export interface PreferencesStore {
   appearance: {
     theme: string
@@ -96,6 +101,7 @@ export interface PreferencesStore {
     notes: NotesEditorSettings
     markdown: MarkdownSettings
   }
+  math: MathSettings
 }
 
 export interface MathSheet {

src/renderer/components/math-notebook/ResultsPanel.vue

@@ -2,13 +2,16 @@
 import type { LineResult } from '@/composables/math-notebook'
 import { Button } from '@/components/ui/shadcn/button'
 import { useCopyToClipboard } from '@/composables'
+import { formatMathNumber } from '@/composables/math-notebook/math-engine/format'
 import { i18n, ipc } from '@/electron'
 import { LoaderCircle, Sigma } from 'lucide-vue-next'
 
 interface Props {
   results: LineResult[]
   scrollTop: number
   activeLine: number
+  locale: string
+  decimalPlaces: number
 }
 
 const props = defineProps<Props>()
@@ -21,7 +24,10 @@ const MATH_NOTEBOOK_DOCUMENTATION_URL
 const total = computed(() => {
   return props.results.reduce((sum, r) => {
     if (r.type === 'number' || r.type === 'assignment') {
-      const num = Number.parseFloat((r.value || '').replace(/,/g, ''))
+      const raw = r.value || ''
+      if (raw.includes(':'))
+        return sum
+      const num = Number.parseFloat(raw.replace(/[^\d.\-e+]/gi, ''))
       if (!Number.isNaN(num))
         return sum + num
     }
@@ -30,9 +36,7 @@ const total = computed(() => {
 })
 
 const formattedTotal = computed(() => {
-  return Number.isInteger(total.value)
-    ? total.value.toLocaleString('en-US')
-    : total.value.toLocaleString('en-US', { maximumFractionDigits: 6 })
+  return formatMathNumber(total.value, props.locale, props.decimalPlaces)
 })
 
 const resultsStyle = computed(() => {

src/renderer/components/math-notebook/Workspace.vue

@@ -1,7 +1,8 @@
 <script setup lang="ts">
 import type { LineResult } from '@/composables/math-notebook'
+import type { MathSettings } from '~/main/store/types'
 import { useMathEngine, useMathNotebook } from '@/composables'
-import { i18n, ipc } from '@/electron'
+import { i18n, ipc, store } from '@/electron'
 import { Calculator } from 'lucide-vue-next'
 
 interface CurrencyRatesPayload {
@@ -10,8 +11,25 @@ interface CurrencyRatesPayload {
 }
 
 const { activeSheet, updateSheet } = useMathNotebook()
-const { evaluateDocument, setCurrencyServiceState, updateCurrencyRates }
-  = useMathEngine()
+const {
+  evaluateDocument,
+  setCurrencyServiceState,
+  setFormatSettings,
+  updateCurrencyRates,
+} = useMathEngine()
+
+const mathSettings = reactive(store.preferences.get('math') as MathSettings)
+
+setFormatSettings(mathSettings.locale, mathSettings.decimalPlaces)
+
+watch(
+  mathSettings,
+  () => {
+    store.preferences.set('math', JSON.parse(JSON.stringify(mathSettings)))
+    setFormatSettings(mathSettings.locale, mathSettings.decimalPlaces)
+  },
+  { deep: true },
+)
 
 const scrollTop = ref(0)
 const activeLine = ref(0)
@@ -98,6 +116,8 @@ function handleActiveLine(line: number) {
       :results="results"
       :scroll-top="scrollTop"
       :active-line="activeLine"
+      :locale="mathSettings.locale"
+      :decimal-places="mathSettings.decimalPlaces"
     />
   </div>
 

src/renderer/components/preferences/Math.vue

@@ -0,0 +1,109 @@
+<script setup lang="ts">
+import type { MathSettings } from '~/main/store/types'
+import * as Select from '@/components/ui/shadcn/select'
+import {
+  formatMathDate,
+  formatMathNumber,
+} from '@/composables/math-notebook/math-engine/format'
+import { i18n, store } from '@/electron'
+
+const settings = reactive(store.preferences.get('math') as MathSettings)
+
+watch(
+  settings,
+  () => {
+    store.preferences.set('math', JSON.parse(JSON.stringify(settings)))
+  },
+  { deep: true },
+)
+
+const localeOptions = [
+  { label: 'English (US)', value: 'en-US' },
+  { label: 'English (UK)', value: 'en-GB' },
+  { label: 'Deutsch', value: 'de-DE' },
+  { label: 'Fran\u00E7ais', value: 'fr-FR' },
+  { label: '\u0420\u0443\u0441\u0441\u043A\u0438\u0439', value: 'ru-RU' },
+  { label: 'Espa\u00F1ol', value: 'es-ES' },
+  { label: 'Portugu\u00EAs (BR)', value: 'pt-BR' },
+  { label: '\u65E5\u672C\u8A9E', value: 'ja-JP' },
+  { label: '\u4E2D\u6587', value: 'zh-CN' },
+  { label: '\uD55C\uAD6D\uC5B4', value: 'ko-KR' },
+  { label: 'Italiano', value: 'it-IT' },
+  { label: 'Polski', value: 'pl-PL' },
+  {
+    label: '\u0423\u043A\u0440\u0430\u0457\u043D\u0441\u044C\u043A\u0430',
+    value: 'uk-UA',
+  },
+  { label: 'T\u00FCrk\u00E7e', value: 'tr-TR' },
+  { label: 'Nederlands', value: 'nl-NL' },
+]
+
+const decimalPlacesOptions = Array.from({ length: 15 }, (_, i) => ({
+  label: String(i),
+  value: String(i),
+}))
+
+const localePreview = computed(() => {
+  const num = formatMathNumber(
+    1234.5678,
+    settings.locale,
+    settings.decimalPlaces,
+  )
+  const date = formatMathDate(new Date(), settings.locale)
+  return `${num} \u00B7 ${date}`
+})
+
+const decimalPlacesPreview = computed(() => {
+  return `1/3 = ${formatMathNumber(1 / 3, settings.locale, settings.decimalPlaces)}`
+})
+</script>
+
+<template>
+  <div class="space-y-4">
+    <UiMenuFormSection :label="i18n.t('preferences:math.label')">
+      <UiMenuFormItem :label="i18n.t('preferences:math.locale.label')">
+        <Select.Select v-model="settings.locale">
+          <Select.SelectTrigger class="w-64">
+            <Select.SelectValue />
+          </Select.SelectTrigger>
+          <Select.SelectContent>
+            <Select.SelectItem
+              v-for="option in localeOptions"
+              :key="option.value"
+              :value="option.value"
+            >
+              {{ option.label }}
+            </Select.SelectItem>
+          </Select.SelectContent>
+        </Select.Select>
+        <template #description>
+          {{ i18n.t("preferences:math.locale.description") }}
+          {{ localePreview }}
+        </template>
+      </UiMenuFormItem>
+      <UiMenuFormItem :label="i18n.t('preferences:math.decimalPlaces.label')">
+        <Select.Select
+          :model-value="String(settings.decimalPlaces)"
+          @update:model-value="settings.decimalPlaces = Number($event)"
+        >
+          <Select.SelectTrigger class="w-64">
+            <Select.SelectValue />
+          </Select.SelectTrigger>
+          <Select.SelectContent>
+            <Select.SelectItem
+              v-for="option in decimalPlacesOptions"
+              :key="option.value"
+              :value="option.value"
+            >
+              {{ option.label }}
+            </Select.SelectItem>
+          </Select.SelectContent>
+        </Select.Select>
+        <template #description>
+          {{ i18n.t("preferences:math.decimalPlaces.description") }}
+          {{ decimalPlacesPreview }}
+        </template>
+      </UiMenuFormItem>
+    </UiMenuFormSection>
+  </div>
+</template>

src/renderer/composables/__tests__/useMathEngine.test.ts

@@ -543,7 +543,7 @@ describe('prev', () => {
     const results = evalLines('fromunix(1446587186)\nprev + 1 day')
     expect(results[1].type).toBe('date')
     expect(results[1].value).toBe(
-      new Date((1446587186 + 86400) * 1000).toLocaleString(),
+      new Date((1446587186 + 86400) * 1000).toLocaleString('en-US'),
     )
   })
 })
@@ -658,7 +658,7 @@ describe('fromunix', () => {
     const result = evalLine('fromunix(1446587186) + 2 day')
     expect(result.type).toBe('date')
     expect(result.value).toBe(
-      new Date((1446587186 + 2 * 86400) * 1000).toLocaleString(),
+      new Date((1446587186 + 2 * 86400) * 1000).toLocaleString('en-US'),
     )
   })
 
@@ -667,16 +667,20 @@ describe('fromunix', () => {
     expect(results[0].type).toBe('assignment')
     expect(results[1].type).toBe('date')
     expect(results[1].value).toBe(
-      new Date((1446587186 + 2 * 86400) * 1000).toLocaleString(),
+      new Date((1446587186 + 2 * 86400) * 1000).toLocaleString('en-US'),
     )
   })
 
   it('local dotted date assignment + 2 day', () => {
     const results = evalLines('x = 12.03.2025\nx + 2 day')
     expect(results[0].type).toBe('assignment')
-    expect(results[0].value).toBe(new Date(2025, 2, 12).toLocaleString())
+    expect(results[0].value).toBe(
+      new Date(2025, 2, 12).toLocaleString('en-US'),
+    )
     expect(results[1].type).toBe('date')
-    expect(results[1].value).toBe(new Date(2025, 2, 14).toLocaleString())
+    expect(results[1].value).toBe(
+      new Date(2025, 2, 14).toLocaleString('en-US'),
+    )
   })
 })
 
@@ -706,7 +710,7 @@ describe('time zones', () => {
     const result = evalLine('time() + 1 day')
     expect(result.type).toBe('date')
     expect(result.value).toBe(
-      new Date('2026-03-07T12:00:00Z').toLocaleString(),
+      new Date('2026-03-07T12:00:00Z').toLocaleString('en-US'),
     )
   })
 
@@ -720,7 +724,7 @@ describe('time zones', () => {
     const result = evalLine('now + 1 day')
     expect(result.type).toBe('date')
     expect(result.value).toBe(
-      new Date('2026-03-07T12:00:00Z').toLocaleString(),
+      new Date('2026-03-07T12:00:00Z').toLocaleString('en-US'),
     )
   })