feat: load invoice templates from JSON files via backend

Templates are now loaded dynamically from data/templates/*.json
via the get_invoice_templates Tauri command instead of being
hardcoded in TypeScript. Preview and PDF renderer switch on
template.layout instead of template.id, allowing custom templates
to reuse built-in layouts with different colors.

src/components/InvoicePreview.vue

@@ -39,7 +39,7 @@ void clientAddress
   <!-- TEMPLATE 1: CLEAN                                                -->
   <!-- ================================================================ -->
   <div
-    v-if="template.id === 'clean'"
+    v-if="template.layout === 'clean'"
     :style="{
       backgroundColor: c.background,
       color: c.bodyText,
@@ -148,7 +148,7 @@ void clientAddress
   <!-- TEMPLATE 2: PROFESSIONAL                                         -->
   <!-- ================================================================ -->
   <div
-    v-else-if="template.id === 'professional'"
+    v-else-if="template.layout === 'professional'"
     :style="{
       backgroundColor: c.background,
       color: c.bodyText,
@@ -246,7 +246,7 @@ void clientAddress
   <!-- TEMPLATE 3: BOLD                                                 -->
   <!-- ================================================================ -->
   <div
-    v-else-if="template.id === 'bold'"
+    v-else-if="template.layout === 'bold'"
     :style="{
       backgroundColor: c.background,
       color: c.bodyText,
@@ -348,7 +348,7 @@ void clientAddress
   <!-- TEMPLATE 4: MINIMAL                                              -->
   <!-- ================================================================ -->
   <div
-    v-else-if="template.id === 'minimal'"
+    v-else-if="template.layout === 'minimal'"
     :style="{
       backgroundColor: c.background,
       color: c.bodyText,
@@ -444,7 +444,7 @@ void clientAddress
   <!-- TEMPLATE 5: CLASSIC                                              -->
   <!-- ================================================================ -->
   <div
-    v-else-if="template.id === 'classic'"
+    v-else-if="template.layout === 'classic'"
     :style="{
       backgroundColor: c.background,
       color: c.bodyText,
@@ -536,7 +536,7 @@ void clientAddress
   <!-- TEMPLATE 6: MODERN                                               -->
   <!-- ================================================================ -->
   <div
-    v-else-if="template.id === 'modern'"
+    v-else-if="template.layout === 'modern'"
     :style="{
       backgroundColor: c.background,
       color: c.bodyText,
@@ -636,7 +636,7 @@ void clientAddress
   <!-- TEMPLATE 7: ELEGANT                                              -->
   <!-- ================================================================ -->
   <div
-    v-else-if="template.id === 'elegant'"
+    v-else-if="template.layout === 'elegant'"
     :style="{
       backgroundColor: c.background,
       color: c.bodyText,
@@ -756,7 +756,7 @@ void clientAddress
   <!-- TEMPLATE 8: CREATIVE                                             -->
   <!-- ================================================================ -->
   <div
-    v-else-if="template.id === 'creative'"
+    v-else-if="template.layout === 'creative'"
     :style="{
       backgroundColor: c.background,
       color: c.bodyText,
@@ -859,7 +859,7 @@ void clientAddress
   <!-- TEMPLATE 9: COMPACT                                              -->
   <!-- ================================================================ -->
   <div
-    v-else-if="template.id === 'compact'"
+    v-else-if="template.layout === 'compact'"
     :style="{
       backgroundColor: c.background,
       color: c.bodyText,
@@ -954,7 +954,7 @@ void clientAddress
   <!-- TEMPLATE 10: DARK                                                -->
   <!-- ================================================================ -->
   <div
-    v-else-if="template.id === 'dark'"
+    v-else-if="template.layout === 'dark'"
     :style="{
       backgroundColor: c.background,
       color: c.bodyText,
@@ -1053,7 +1053,7 @@ void clientAddress
   <!-- TEMPLATE 11: VIBRANT                                             -->
   <!-- ================================================================ -->
   <div
-    v-else-if="template.id === 'vibrant'"
+    v-else-if="template.layout === 'vibrant'"
     :style="{
       backgroundColor: c.background,
       color: c.bodyText,
@@ -1151,7 +1151,7 @@ void clientAddress
   <!-- TEMPLATE 12: CORPORATE                                           -->
   <!-- ================================================================ -->
   <div
-    v-else-if="template.id === 'corporate'"
+    v-else-if="template.layout === 'corporate'"
     :style="{
       backgroundColor: c.background,
       color: c.bodyText,
@@ -1249,7 +1249,7 @@ void clientAddress
   <!-- TEMPLATE 13: FRESH                                               -->
   <!-- ================================================================ -->
   <div
-    v-else-if="template.id === 'fresh'"
+    v-else-if="template.layout === 'fresh'"
     :style="{
       backgroundColor: c.background,
       color: c.bodyText,
@@ -1352,7 +1352,7 @@ void clientAddress
   <!-- TEMPLATE 14: NATURAL                                             -->
   <!-- ================================================================ -->
   <div
-    v-else-if="template.id === 'natural'"
+    v-else-if="template.layout === 'natural'"
     :style="{
       backgroundColor: c.background,
       color: c.bodyText,
@@ -1452,7 +1452,7 @@ void clientAddress
   <!-- TEMPLATE 15: STATEMENT                                           -->
   <!-- ================================================================ -->
   <div
-    v-else-if="template.id === 'statement'"
+    v-else-if="template.layout === 'statement'"
     :style="{
       backgroundColor: c.background,
       color: c.bodyText,

src/utils/invoicePdfRenderer.ts

@@ -1825,7 +1825,7 @@ export function renderInvoicePdf(
   items: InvoiceItem[],
   businessInfo: BusinessInfo,
 ): jsPDF {
-  switch (config.id) {
+  switch (config.layout) {
     case 'clean': return renderClean(config, invoice, client, items, businessInfo)
     case 'professional': return renderProfessional(config, invoice, client, items, businessInfo)
     case 'bold': return renderBold(config, invoice, client, items, businessInfo)

src/utils/invoiceTemplates.ts

@@ -1,3 +1,6 @@
+import { ref } from 'vue'
+import { invoke } from '@tauri-apps/api/core'
+
 export interface InvoiceTemplateColors {
   primary: string
   secondary: string
@@ -15,318 +18,12 @@ export interface InvoiceTemplateColors {
 export interface InvoiceTemplateConfig {
   id: string
   name: string
-  category: 'essential' | 'creative' | 'warm' | 'premium'
+  layout: string
+  category: string
   description: string
   colors: InvoiceTemplateColors
 }
 
-const clean: InvoiceTemplateConfig = {
-  id: 'clean',
-  name: 'Clean',
-  category: 'essential',
-  description: 'Swiss minimalism with a single blue accent',
-  colors: {
-    primary: '#1e293b',
-    secondary: '#3b82f6',
-    background: '#ffffff',
-    headerBg: '#ffffff',
-    headerText: '#1e293b',
-    bodyText: '#374151',
-    tableHeaderBg: '#f8fafc',
-    tableHeaderText: '#374151',
-    tableRowAlt: '#f8fafc',
-    tableBorder: '#e5e7eb',
-    totalHighlight: '#3b82f6',
-  },
-}
-
-const professional: InvoiceTemplateConfig = {
-  id: 'professional',
-  name: 'Professional',
-  category: 'essential',
-  description: 'Navy header band with corporate polish',
-  colors: {
-    primary: '#1e3a5f',
-    secondary: '#2563eb',
-    background: '#ffffff',
-    headerBg: '#1e3a5f',
-    headerText: '#ffffff',
-    bodyText: '#374151',
-    tableHeaderBg: '#1e3a5f',
-    tableHeaderText: '#ffffff',
-    tableRowAlt: '#f3f4f6',
-    tableBorder: '#d1d5db',
-    totalHighlight: '#1e3a5f',
-  },
-}
-
-const bold: InvoiceTemplateConfig = {
-  id: 'bold',
-  name: 'Bold',
-  category: 'essential',
-  description: 'Large indigo block with oversized typography',
-  colors: {
-    primary: '#4f46e5',
-    secondary: '#a5b4fc',
-    background: '#ffffff',
-    headerBg: '#4f46e5',
-    headerText: '#ffffff',
-    bodyText: '#1f2937',
-    tableHeaderBg: '#4f46e5',
-    tableHeaderText: '#ffffff',
-    tableRowAlt: '#f5f3ff',
-    tableBorder: '#e0e7ff',
-    totalHighlight: '#4f46e5',
-  },
-}
-
-const minimal: InvoiceTemplateConfig = {
-  id: 'minimal',
-  name: 'Minimal',
-  category: 'essential',
-  description: 'Pure monochrome centered layout',
-  colors: {
-    primary: '#18181b',
-    secondary: '#18181b',
-    background: '#ffffff',
-    headerBg: '#ffffff',
-    headerText: '#18181b',
-    bodyText: '#3f3f46',
-    tableHeaderBg: '#ffffff',
-    tableHeaderText: '#18181b',
-    tableRowAlt: '#ffffff',
-    tableBorder: '#e4e4e7',
-    totalHighlight: '#18181b',
-  },
-}
-
-const classic: InvoiceTemplateConfig = {
-  id: 'classic',
-  name: 'Classic',
-  category: 'essential',
-  description: 'Traditional layout with burgundy accents',
-  colors: {
-    primary: '#7f1d1d',
-    secondary: '#991b1b',
-    background: '#ffffff',
-    headerBg: '#7f1d1d',
-    headerText: '#ffffff',
-    bodyText: '#374151',
-    tableHeaderBg: '#7f1d1d',
-    tableHeaderText: '#ffffff',
-    tableRowAlt: '#f5f5f4',
-    tableBorder: '#d6d3d1',
-    totalHighlight: '#7f1d1d',
-  },
-}
-
-const modern: InvoiceTemplateConfig = {
-  id: 'modern',
-  name: 'Modern',
-  category: 'creative',
-  description: 'Asymmetric header with teal accents',
-  colors: {
-    primary: '#0d9488',
-    secondary: '#14b8a6',
-    background: '#ffffff',
-    headerBg: '#ffffff',
-    headerText: '#0f172a',
-    bodyText: '#334155',
-    tableHeaderBg: '#ffffff',
-    tableHeaderText: '#0d9488',
-    tableRowAlt: '#f0fdfa',
-    tableBorder: '#99f6e4',
-    totalHighlight: '#0d9488',
-  },
-}
-
-const elegant: InvoiceTemplateConfig = {
-  id: 'elegant',
-  name: 'Elegant',
-  category: 'creative',
-  description: 'Gold double-rule accents on centered layout',
-  colors: {
-    primary: '#a16207',
-    secondary: '#ca8a04',
-    background: '#ffffff',
-    headerBg: '#ffffff',
-    headerText: '#422006',
-    bodyText: '#57534e',
-    tableHeaderBg: '#ffffff',
-    tableHeaderText: '#422006',
-    tableRowAlt: '#fefce8',
-    tableBorder: '#a16207',
-    totalHighlight: '#a16207',
-  },
-}
-
-const creative: InvoiceTemplateConfig = {
-  id: 'creative',
-  name: 'Creative',
-  category: 'creative',
-  description: 'Purple sidebar with card-style rows',
-  colors: {
-    primary: '#7c3aed',
-    secondary: '#a78bfa',
-    background: '#ffffff',
-    headerBg: '#ffffff',
-    headerText: '#1f2937',
-    bodyText: '#374151',
-    tableHeaderBg: '#faf5ff',
-    tableHeaderText: '#7c3aed',
-    tableRowAlt: '#faf5ff',
-    tableBorder: '#e9d5ff',
-    totalHighlight: '#7c3aed',
-  },
-}
-
-const compact: InvoiceTemplateConfig = {
-  id: 'compact',
-  name: 'Compact',
-  category: 'creative',
-  description: 'Data-dense layout with tight spacing',
-  colors: {
-    primary: '#475569',
-    secondary: '#64748b',
-    background: '#ffffff',
-    headerBg: '#ffffff',
-    headerText: '#0f172a',
-    bodyText: '#334155',
-    tableHeaderBg: '#f1f5f9',
-    tableHeaderText: '#334155',
-    tableRowAlt: '#f8fafc',
-    tableBorder: '#e2e8f0',
-    totalHighlight: '#475569',
-  },
-}
-
-const dark: InvoiceTemplateConfig = {
-  id: 'dark',
-  name: 'Dark',
-  category: 'warm',
-  description: 'Near-black background with cyan highlights',
-  colors: {
-    primary: '#06b6d4',
-    secondary: '#22d3ee',
-    background: '#0f172a',
-    headerBg: '#020617',
-    headerText: '#e2e8f0',
-    bodyText: '#cbd5e1',
-    tableHeaderBg: '#020617',
-    tableHeaderText: '#06b6d4',
-    tableRowAlt: '#1e293b',
-    tableBorder: '#334155',
-    totalHighlight: '#06b6d4',
-  },
-}
-
-const vibrant: InvoiceTemplateConfig = {
-  id: 'vibrant',
-  name: 'Vibrant',
-  category: 'warm',
-  description: 'Coral-to-orange gradient header band',
-  colors: {
-    primary: '#ea580c',
-    secondary: '#f97316',
-    background: '#ffffff',
-    headerBg: '#ea580c',
-    headerText: '#ffffff',
-    bodyText: '#1f2937',
-    tableHeaderBg: '#fff7ed',
-    tableHeaderText: '#9a3412',
-    tableRowAlt: '#fff7ed',
-    tableBorder: '#fed7aa',
-    totalHighlight: '#ea580c',
-  },
-}
-
-const corporate: InvoiceTemplateConfig = {
-  id: 'corporate',
-  name: 'Corporate',
-  category: 'warm',
-  description: 'Deep blue header with info bar below',
-  colors: {
-    primary: '#1e40af',
-    secondary: '#3b82f6',
-    background: '#ffffff',
-    headerBg: '#1e40af',
-    headerText: '#ffffff',
-    bodyText: '#1f2937',
-    tableHeaderBg: '#1e40af',
-    tableHeaderText: '#ffffff',
-    tableRowAlt: '#eff6ff',
-    tableBorder: '#bfdbfe',
-    totalHighlight: '#1e40af',
-  },
-}
-
-const fresh: InvoiceTemplateConfig = {
-  id: 'fresh',
-  name: 'Fresh',
-  category: 'premium',
-  description: 'Oversized watermark invoice number',
-  colors: {
-    primary: '#0284c7',
-    secondary: '#38bdf8',
-    background: '#ffffff',
-    headerBg: '#ffffff',
-    headerText: '#0c4a6e',
-    bodyText: '#334155',
-    tableHeaderBg: '#0284c7',
-    tableHeaderText: '#ffffff',
-    tableRowAlt: '#f0f9ff',
-    tableBorder: '#bae6fd',
-    totalHighlight: '#0284c7',
-  },
-}
-
-const natural: InvoiceTemplateConfig = {
-  id: 'natural',
-  name: 'Natural',
-  category: 'premium',
-  description: 'Warm beige background with terracotta accents',
-  colors: {
-    primary: '#c2703e',
-    secondary: '#d97706',
-    background: '#fdf6ec',
-    headerBg: '#fdf6ec',
-    headerText: '#78350f',
-    bodyText: '#57534e',
-    tableHeaderBg: '#c2703e',
-    tableHeaderText: '#ffffff',
-    tableRowAlt: '#fef3c7',
-    tableBorder: '#d6d3d1',
-    totalHighlight: '#c2703e',
-  },
-}
-
-const statement: InvoiceTemplateConfig = {
-  id: 'statement',
-  name: 'Statement',
-  category: 'premium',
-  description: 'Total-forward design with hero amount',
-  colors: {
-    primary: '#18181b',
-    secondary: '#be123c',
-    background: '#ffffff',
-    headerBg: '#ffffff',
-    headerText: '#18181b',
-    bodyText: '#3f3f46',
-    tableHeaderBg: '#ffffff',
-    tableHeaderText: '#18181b',
-    tableRowAlt: '#ffffff',
-    tableBorder: '#e4e4e7',
-    totalHighlight: '#be123c',
-  },
-}
-
-export const INVOICE_TEMPLATES: InvoiceTemplateConfig[] = [
-  clean, professional, bold, minimal, classic,
-  modern, elegant, creative, compact,
-  dark, vibrant, corporate,
-  fresh, natural, statement,
-]
-
 export const TEMPLATE_CATEGORIES = [
   { id: 'essential', label: 'Professional Essentials' },
   { id: 'creative', label: 'Creative & Modern' },
@@ -334,10 +31,36 @@ export const TEMPLATE_CATEGORIES = [
   { id: 'premium', label: 'Premium & Specialized' },
 ] as const
 
+const templates = ref<InvoiceTemplateConfig[]>([])
+let loaded = false
+
+export async function loadTemplates(): Promise<InvoiceTemplateConfig[]> {
+  if (loaded && templates.value.length > 0) return templates.value
+  try {
+    templates.value = await invoke<InvoiceTemplateConfig[]>('get_invoice_templates')
+    loaded = true
+  } catch (e) {
+    console.error('Failed to load invoice templates:', e)
+  }
+  return templates.value
+}
+
+export function getLoadedTemplates(): InvoiceTemplateConfig[] {
+  return templates.value
+}
+
 export function getTemplateById(id: string): InvoiceTemplateConfig {
-  return INVOICE_TEMPLATES.find(t => t.id === id) || INVOICE_TEMPLATES[0]
+  return templates.value.find(t => t.id === id) || templates.value[0] || {
+    id: 'clean', name: 'Clean', layout: 'clean', category: 'essential',
+    description: 'Default', colors: {
+      primary: '#1e293b', secondary: '#3b82f6', background: '#ffffff',
+      headerBg: '#ffffff', headerText: '#1e293b', bodyText: '#374151',
+      tableHeaderBg: '#f8fafc', tableHeaderText: '#374151',
+      tableRowAlt: '#f8fafc', tableBorder: '#e5e7eb', totalHighlight: '#3b82f6',
+    },
+  }
 }
 
 export function getTemplatesByCategory(category: string): InvoiceTemplateConfig[] {
-  return INVOICE_TEMPLATES.filter(t => t.category === category)
+  return templates.value.filter(t => t.category === category)
 }

src/views/Invoices.vue

@@ -506,7 +506,7 @@ import AppNumberInput from '../components/AppNumberInput.vue'
 import AppSelect from '../components/AppSelect.vue'
 import AppDatePicker from '../components/AppDatePicker.vue'
 import InvoicePreview from '../components/InvoicePreview.vue'
-import { getTemplateById, getTemplatesByCategory, TEMPLATE_CATEGORIES } from '../utils/invoiceTemplates'
+import { getTemplateById, getTemplatesByCategory, loadTemplates, TEMPLATE_CATEGORIES } from '../utils/invoiceTemplates'
 import type { BusinessInfo } from '../utils/invoicePdfRenderer'
 import { useInvoicesStore, type Invoice, type InvoiceItem } from '../stores/invoices'
 import { useClientsStore, type Client } from '../stores/clients'
@@ -794,6 +794,7 @@ onMounted(async () => {
     clientsStore.fetchClients(),
     projectsStore.fetchProjects(),
     settingsStore.fetchSettings(),
+    loadTemplates(),
   ])
 })
 </script>