feat: add HelpText model, service, and controller for dynamic help text management

backend/prisma/migrations/20260513150000_add_help_texts/migration.sql

@@ -0,0 +1,35 @@
+CREATE TABLE `HelpText` (
+  `id` INTEGER NOT NULL AUTO_INCREMENT,
+  `key` VARCHAR(191) NOT NULL,
+  `scope` VARCHAR(191) NOT NULL DEFAULT 'default',
+  `title` VARCHAR(191) NOT NULL,
+  `content` TEXT NOT NULL,
+  `isActive` BOOLEAN NOT NULL DEFAULT true,
+  `createdAt` DATETIME(3) NOT NULL DEFAULT CURRENT_TIMESTAMP(3),
+  `updatedAt` DATETIME(3) NOT NULL,
+
+  UNIQUE INDEX `HelpText_key_scope_key`(`key`, `scope`),
+  INDEX `HelpText_key_isActive_idx`(`key`, `isActive`),
+  PRIMARY KEY (`id`)
+) DEFAULT CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;
+
+INSERT INTO `HelpText` (`key`, `scope`, `title`, `content`, `isActive`, `createdAt`, `updatedAt`)
+VALUES
+(
+  'receipt_import',
+  'default',
+  'Hjälp: Kvittoimport',
+  'Kvittoimporten hjälper dig att tolka kvitton och lägga till varor i inventarie eller baslager.\n\nSteg:\n1. Ladda upp PDF eller bild.\n2. Granska raderna och justera produkt, mängd och enhet vid behov.\n3. Välj destination (inventarie eller baslager).\n4. Spara markerade rader.\n\nTips:\n- Om en rad är osäker, redigera innan du sparar.\n- Du kan lära in alias för bättre träffar nästa gång.',
+  true,
+  NOW(3),
+  NOW(3)
+),
+(
+  'receipt_import',
+  'admin',
+  'Hjälp: Kvittoimport för administratörer',
+  'Kvittoimporten hjälper dig att läsa in kvitton och omvandla rader till produkter i inventarie eller baslager. Som administratör har du utökade möjligheter att förbättra träffsäkerheten för hela systemet.\n\nSå fungerar flödet:\n1. Ladda upp kvitto som PDF eller bild.\n2. Systemet tolkar raderna och föreslår produktmatchning, mängd och enhet.\n3. Granska varje rad innan du sparar.\n4. Välj destination: Inventarie eller Baslager.\n5. Spara valda rader.\n\nMatchning och förslag:\n- Alias-träff: raden matchar mot inlärda alias.\n- Ordbaserad träff: systemet hittar sannolik produkt, men du bör bekräfta.\n- AI-kategoriförslag: visas som stöd när produkt inte matchas direkt.\n\nDet du kan göra per rad:\n- Byta till annan befintlig produkt.\n- Skapa ny produkt om ingen passande finns.\n- Justera mängd, enhet och paketinformation.\n- Välja kategori manuellt vid behov.\n- Markera om alias ska läras in.\n\nAdmin-funktioner i kvittoimport:\n- Du kan spara globala alias som blir fallback för alla användare.\n- Du kan använda privata alias för egna avvikelser.\n- Du kan efter import gå vidare till admin-vyer för att städa dubbletter och kvalitetssäkra data.\n\nRekommenderat arbetssätt:\n- Kontrollera rader med låg säkerhet först.\n- Skapa globala alias bara för stabila och återkommande kvittonamn.\n- Undvik att skapa för många nästan-identiska produkter.',
+  true,
+  NOW(3),
+  NOW(3)
+);

backend/prisma/schema.prisma

@@ -263,3 +263,17 @@ model UnitMapping {
   @@index([productId])
   @@index([userId])
 }
+
+model HelpText {
+  id        Int      @id @default(autoincrement())
+  key       String
+  scope     String   @default("default")
+  title     String
+  content   String   @db.Text
+  isActive  Boolean  @default(true)
+  createdAt DateTime @default(now())
+  updatedAt DateTime @updatedAt
+
+  @@unique([key, scope])
+  @@index([key, isActive])
+}

backend/src/app.module.ts

@@ -17,6 +17,7 @@ import { UserProductsModule } from './user-products/user-products.module';
 import { CategoriesModule } from './categories/categories.module';
 import { AiModule } from './ai/ai.module';
 import { RealtimeModule } from './realtime/realtime.module';
+import { HelpTextsModule } from './help-texts/help-texts.module';
 import { JwtAuthGuard } from './auth/jwt-auth.guard';
 import { RolesGuard } from './auth/roles.guard';
 
@@ -46,6 +47,7 @@ import { RolesGuard } from './auth/roles.guard';
     CategoriesModule,
     AiModule,
     RealtimeModule,
+    HelpTextsModule,
   ],
   providers: [
     {

backend/src/help-texts/dto/upsert-help-text.dto.ts

@@ -0,0 +1,14 @@
+import { IsBoolean, IsOptional, IsString, MaxLength } from 'class-validator';
+
+export class UpsertHelpTextDto {
+  @IsString()
+  @MaxLength(120)
+  title!: string;
+
+  @IsString()
+  content!: string;
+
+  @IsOptional()
+  @IsBoolean()
+  isActive?: boolean;
+}

backend/src/help-texts/help-texts.controller.ts

@@ -0,0 +1,28 @@
+import { Body, Controller, Get, Param, Put } from '@nestjs/common';
+import { CurrentUser } from '../auth/decorators/current-user.decorator';
+import { Roles } from '../auth/decorators/roles.decorator';
+import { UpsertHelpTextDto } from './dto/upsert-help-text.dto';
+import { HelpTextsService } from './help-texts.service';
+
+@Controller('help-texts')
+export class HelpTextsController {
+  constructor(private readonly helpTextsService: HelpTextsService) {}
+
+  @Get(':key')
+  getByKey(
+    @Param('key') key: string,
+    @CurrentUser() user: { role?: string },
+  ) {
+    return this.helpTextsService.getResolvedByKey(key, user?.role);
+  }
+
+  @Roles('admin')
+  @Put(':key/:scope')
+  upsert(
+    @Param('key') key: string,
+    @Param('scope') scope: string,
+    @Body() dto: UpsertHelpTextDto,
+  ) {
+    return this.helpTextsService.upsert(key, scope, dto);
+  }
+}

backend/src/help-texts/help-texts.module.ts

@@ -0,0 +1,11 @@
+import { Module } from '@nestjs/common';
+import { PrismaModule } from '../prisma/prisma.module';
+import { HelpTextsController } from './help-texts.controller';
+import { HelpTextsService } from './help-texts.service';
+
+@Module({
+  imports: [PrismaModule],
+  controllers: [HelpTextsController],
+  providers: [HelpTextsService],
+})
+export class HelpTextsModule {}

backend/src/help-texts/help-texts.service.ts

@@ -0,0 +1,99 @@
+import { BadRequestException, Injectable, NotFoundException } from '@nestjs/common';
+import { PrismaService } from '../prisma/prisma.service';
+import { UpsertHelpTextDto } from './dto/upsert-help-text.dto';
+
+type HelpTextScope = 'default' | 'user' | 'admin';
+
+@Injectable()
+export class HelpTextsService {
+  private readonly allowedScopes: HelpTextScope[] = ['default', 'user', 'admin'];
+
+  constructor(private readonly prisma: PrismaService) {}
+
+  async getResolvedByKey(keyRaw: string, roleRaw?: string) {
+    const key = this.normalizeKey(keyRaw);
+    const role = (roleRaw ?? 'user').toLowerCase();
+    const scopePriority: HelpTextScope[] = role === 'admin'
+      ? ['admin', 'user', 'default']
+      : ['user', 'default'];
+
+    const rows = await this.prisma.helpText.findMany({
+      where: {
+        key,
+        isActive: true,
+        scope: { in: scopePriority },
+      },
+      select: {
+        key: true,
+        scope: true,
+        title: true,
+        content: true,
+        updatedAt: true,
+      },
+    });
+
+    for (const scope of scopePriority) {
+      const hit = rows.find((row) => row.scope === scope);
+      if (hit) {
+        return {
+          'key': hit.key,
+          'scope': hit.scope,
+          'title': hit.title,
+          'content': hit.content,
+          'updatedAt': hit.updatedAt,
+        };
+      }
+    }
+
+    throw new NotFoundException(`Ingen aktiv hjälptext hittades för key '${key}'.`);
+  }
+
+  async upsert(keyRaw: string, scopeRaw: string, dto: UpsertHelpTextDto) {
+    const key = this.normalizeKey(keyRaw);
+    const scope = this.normalizeScope(scopeRaw);
+
+    return this.prisma.helpText.upsert({
+      where: {
+        key_scope: { key, scope },
+      },
+      update: {
+        title: dto.title.trim(),
+        content: dto.content.trim(),
+        isActive: dto.isActive ?? true,
+      },
+      create: {
+        key,
+        scope,
+        title: dto.title.trim(),
+        content: dto.content.trim(),
+        isActive: dto.isActive ?? true,
+      },
+      select: {
+        key: true,
+        scope: true,
+        title: true,
+        content: true,
+        isActive: true,
+        updatedAt: true,
+      },
+    });
+  }
+
+  private normalizeKey(value: string): string {
+    const normalized = value.trim().toLowerCase();
+    if (!normalized) {
+      throw new BadRequestException('Hjälptext-nyckel måste anges.');
+    }
+    return normalized;
+  }
+
+  private normalizeScope(value: string): HelpTextScope {
+    const normalized = value.trim().toLowerCase() as HelpTextScope;
+    if (!this.allowedScopes.includes(normalized)) {
+      throw new BadRequestException(
+        `Ogiltig scope '${value}'. Tillåtna scopes: ${this.allowedScopes.join(', ')}`,
+      );
+    }
+    return normalized;
+  }
+}

flutter/lib/core/api/api_paths.dart

@@ -38,6 +38,10 @@ class ReceiptImportApiPaths {
   static const unitMappings = '/receipt-import/unit-mappings';
 }
 
+class HelpTextApiPaths {
+  static String byKey(String key) => '/help-texts/${Uri.encodeComponent(key)}';
+}
+
 class ReceiptAliasApiPaths {
   static const list = '/receipt-aliases';
   static String update(int id) => '/receipt-aliases/$id';

flutter/lib/features/import/data/import_repository.dart

@@ -7,6 +7,7 @@ import 'dart:developer' as developer;
 
 import '../../../core/api/api_paths.dart';
 import '../../../core/api/api_exception.dart';
+import '../domain/help_text_content.dart';
 import '../domain/quick_import_result.dart';
 
 /// Handles communication with the quick-import API endpoint.
@@ -25,6 +26,38 @@ class ImportRepository {
           defaultValue: '/api',
         );
 
+  Future<HelpTextContent> fetchHelpTextByKey(
+    String key, {
+    String? token,
+  }) async {
+    final uri = Uri.parse('$_baseUrl${HelpTextApiPaths.byKey(key)}');
+    final response = await _client.get(
+      uri,
+      headers: {
+        'Content-Type': 'application/json',
+        if (token != null) 'Authorization': 'Bearer $token',
+      },
+    );
+
+    if (response.statusCode < 200 || response.statusCode >= 300) {
+      throw ApiException(
+        type: _mapStatusCodeToErrorType(response.statusCode),
+        message: 'Kunde inte hämta hjälptext: ${response.body}',
+        statusCode: response.statusCode,
+      );
+    }
+
+    final parsed = _parseResponse(response);
+    if (parsed is! Map<String, dynamic>) {
+      throw ApiException(
+        type: ApiErrorType.unknown,
+        message: 'Felaktigt svar vid hämtning av hjälptext.',
+      );
+    }
+
+    return HelpTextContent.fromJson(parsed);
+  }
+
   /// Upload a receipt file for parsing (Fas 6b).
   /// Returns a list of parsed receipt items.
   Future<List<ParsedReceiptItem>> importReceiptFile({

flutter/lib/features/import/domain/help_text_content.dart

@@ -0,0 +1,27 @@
+class HelpTextContent {
+  final String key;
+  final String scope;
+  final String title;
+  final String content;
+  final DateTime? updatedAt;
+
+  const HelpTextContent({
+    required this.key,
+    required this.scope,
+    required this.title,
+    required this.content,
+    this.updatedAt,
+  });
+
+  factory HelpTextContent.fromJson(Map<String, dynamic> json) {
+    return HelpTextContent(
+      key: (json['key'] as String? ?? '').trim(),
+      scope: (json['scope'] as String? ?? 'default').trim(),
+      title: (json['title'] as String? ?? '').trim(),
+      content: (json['content'] as String? ?? '').trim(),
+      updatedAt: json['updatedAt'] is String
+          ? DateTime.tryParse(json['updatedAt'] as String)
+          : null,
+    );
+  }
+}

flutter/lib/features/import/presentation/receipt_import_tab.dart

@@ -14,6 +14,7 @@ import '../../pantry/data/pantry_providers.dart';
 import '../../pantry/domain/pantry_item.dart';
 import '../data/import_providers.dart';
 import '../data/receipt_import_session.dart';
+import '../domain/help_text_content.dart';
 import '../domain/parsed_receipt_item.dart';
 import '../../../core/ui/product_picker_field.dart' show ProductOption;
 import '../utils/receipt_import_utils.dart';
@@ -37,6 +38,7 @@ class ReceiptImportTab extends ConsumerStatefulWidget {
 class _ReceiptImportTabState extends ConsumerState<ReceiptImportTab> {
   bool _isLoading = false;
   bool _isSaving = false;
+  bool _isHelpLoading = false;
   PlatformFile? _pickedFile;
   bool _categoryLoadFailed = false;
   bool _globalProductsLoadFailed = false;
@@ -460,6 +462,64 @@ class _ReceiptImportTabState extends ConsumerState<ReceiptImportTab> {
     );
   }
 
+  Future<void> _showHelpForReceiptImport() async {
+    if (_isHelpLoading) return;
+    setState(() => _isHelpLoading = true);
+    try {
+      final token = await ref.read(authStateProvider.future);
+      final repo = ref.read(importRepositoryProvider);
+      final help = await repo.fetchHelpTextByKey('receipt_import', token: token);
+      if (!mounted) return;
+      await _showHelpDialog(help);
+    } catch (e) {
+      if (!mounted) return;
+      showGlobalErrorDialog(context, 'Kunde inte läsa hjälptexten just nu: $e');
+    } finally {
+      if (mounted) setState(() => _isHelpLoading = false);
+    }
+  }
+
+  Future<void> _showHelpDialog(HelpTextContent help) {
+    final updatedAt = help.updatedAt;
+    final updatedAtText = updatedAt == null
+        ? null
+        : '${updatedAt.year.toString().padLeft(4, '0')}-${updatedAt.month.toString().padLeft(2, '0')}-${updatedAt.day.toString().padLeft(2, '0')}';
+
+    return showDialog<void>(
+      context: context,
+      builder: (ctx) => AlertDialog(
+        title: Text(help.title.isEmpty ? 'Hjälp: Kvittoimport' : help.title),
+        content: SizedBox(
+          width: 560,
+          child: SingleChildScrollView(
+            child: Column(
+              crossAxisAlignment: CrossAxisAlignment.start,
+              mainAxisSize: MainAxisSize.min,
+              children: [
+                SelectableText(help.content),
+                const SizedBox(height: 12),
+                Wrap(
+                  spacing: 8,
+                  runSpacing: 8,
+                  children: [
+                    Chip(label: Text('Scope: ${help.scope}')),
+                    if (updatedAtText != null) Chip(label: Text('Uppdaterad: $updatedAtText')),
+                  ],
+                ),
+              ],
+            ),
+          ),
+        ),
+        actions: [
+          TextButton(
+            onPressed: () => Navigator.of(ctx).pop(),
+            child: const Text('Stäng'),
+          ),
+        ],
+      ),
+    );
+  }
+
   void _deleteItem(int index) {
     final items = _items;
     if (items == null || index < 0 || index >= items.length) return;
@@ -819,9 +879,28 @@ class _ReceiptImportTabState extends ConsumerState<ReceiptImportTab> {
       child: Column(
         crossAxisAlignment: CrossAxisAlignment.start,
         children: [
-          Text(
+          Row(
-            'Ladda upp ett kvitto (PDF eller bild) — raderna tolkas och kan läggas till i ditt inventarie.',
+            crossAxisAlignment: CrossAxisAlignment.start,
-            style: theme.textTheme.bodyMedium?.copyWith(color: theme.colorScheme.onSurfaceVariant),
+            children: [
+              Expanded(
+                child: Text(
+                  'Ladda upp ett kvitto (PDF eller bild) — raderna tolkas och kan läggas till i ditt inventarie.',
+                  style: theme.textTheme.bodyMedium?.copyWith(color: theme.colorScheme.onSurfaceVariant),
+                ),
+              ),
+              const SizedBox(width: 8),
+              TextButton.icon(
+                onPressed: _isHelpLoading ? null : _showHelpForReceiptImport,
+                icon: _isHelpLoading
+                    ? const SizedBox(
+                        width: 14,
+                        height: 14,
+                        child: CircularProgressIndicator(strokeWidth: 2),
+                      )
+                    : const Icon(Icons.help_outline),
+                label: const Text('Läs hjälp'),
+              ),
+            ],
           ),
           const SizedBox(height: 20),
           OutlinedButton.icon(