feat(todo): add deep validation for DTOs and completed task pagination

Validation:
- Create SubtaskDto with title MinLength/MaxLength, order validation
- Create TaskMetadataDto with typed EffectiveDuration, storyPoints enum
  validation (Fibonacci only), funRating bounds (1-10)
- Use @ValidateNested with @Type() for deep validation in CreateTaskDto

Pagination:
- Add offset parameter and total count to getCompletedTasks()
- Return { tasks, total, hasMore } structure for frontend pagination
- Enforce max limit of 100 to prevent abuse
- Add 3 pagination tests (basic, offset, max enforcement)

Error handling:
- Add try-catch to localStorage operations in +layout.svelte
- Handles private browsing mode and quota exceeded errors gracefully

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

apps/todo/apps/backend/src/task/__tests__/task.service.spec.ts

@@ -5,6 +5,9 @@ import { ProjectService } from '../../project/project.service';
 import { DATABASE_CONNECTION } from '../../db/database.module';
 
 // Mock database
+const mockSelectFrom = jest.fn().mockReturnThis();
+const mockSelectWhere = jest.fn();
+
 const mockDb = {
 	query: {
 		tasks: {
@@ -18,6 +21,10 @@ const mockDb = {
 			findMany: jest.fn(),
 		},
 	},
+	select: jest.fn().mockReturnValue({
+		from: mockSelectFrom,
+		where: mockSelectWhere,
+	}),
 	insert: jest.fn().mockReturnThis(),
 	update: jest.fn().mockReturnThis(),
 	delete: jest.fn().mockReturnThis(),
@@ -406,7 +413,7 @@ describe('TaskService', () => {
 	});
 
 	describe('getCompletedTasks', () => {
-		it('should return completed tasks with default limit', async () => {
+		it('should return completed tasks with pagination info', async () => {
 			const userId = 'user-123';
 			const mockTasks = Array(50)
 				.fill(null)
@@ -419,13 +426,16 @@ describe('TaskService', () => {
 
 			mockDb.query.tasks.findMany.mockResolvedValue(mockTasks);
 			mockDb.query.taskLabels.findMany.mockResolvedValue([]);
+			mockSelectWhere.mockResolvedValue([{ count: 75 }]);
 
 			const result = await service.getCompletedTasks(userId);
 
-			expect(result).toHaveLength(50);
+			expect(result.tasks).toHaveLength(50);
+			expect(result.total).toBe(75);
+			expect(result.hasMore).toBe(true);
 		});
 
-		it('should respect custom limit', async () => {
+		it('should respect custom limit and offset', async () => {
 			const userId = 'user-123';
 			const mockTasks = Array(10)
 				.fill(null)
@@ -438,10 +448,35 @@ describe('TaskService', () => {
 
 			mockDb.query.tasks.findMany.mockResolvedValue(mockTasks);
 			mockDb.query.taskLabels.findMany.mockResolvedValue([]);
+			mockSelectWhere.mockResolvedValue([{ count: 25 }]);
 
-			const result = await service.getCompletedTasks(userId, 10);
+			const result = await service.getCompletedTasks(userId, 10, 10);
 
-			expect(result).toHaveLength(10);
+			expect(result.tasks).toHaveLength(10);
+			expect(result.total).toBe(25);
+			expect(result.hasMore).toBe(true); // offset 10 + limit 10 = 20 < 25
+		});
+
+		it('should enforce max limit of 100', async () => {
+			const userId = 'user-123';
+			const mockTasks = Array(100)
+				.fill(null)
+				.map((_, i) => ({
+					id: `task-${i}`,
+					title: `Task ${i}`,
+					userId,
+					isCompleted: true,
+				}));
+
+			mockDb.query.tasks.findMany.mockResolvedValue(mockTasks);
+			mockDb.query.taskLabels.findMany.mockResolvedValue([]);
+			mockSelectWhere.mockResolvedValue([{ count: 200 }]);
+
+			// Request 500 tasks, should be capped at 100
+			const result = await service.getCompletedTasks(userId, 500, 0);
+
+			expect(result.tasks).toHaveLength(100);
+			expect(result.hasMore).toBe(true);
 		});
 	});
 

apps/todo/apps/backend/src/task/dto/create-task.dto.ts

@@ -4,13 +4,16 @@ import {
 	IsUUID,
 	IsEnum,
 	IsArray,
-	IsObject,
 	MaxLength,
 	MinLength,
 	IsDateString,
 	IsNotEmpty,
+	ValidateNested,
 } from 'class-validator';
-import type { TaskPriority, Subtask, TaskMetadata } from '../../db/schema/tasks.schema';
+import { Type } from 'class-transformer';
+import type { TaskPriority } from '../../db/schema/tasks.schema';
+import { CreateSubtaskDto } from './subtask.dto';
+import { TaskMetadataDto } from './metadata.dto';
 
 export class CreateTaskDto {
 	@IsString()
@@ -58,7 +61,9 @@ export class CreateTaskDto {
 
 	@IsOptional()
 	@IsArray()
-	subtasks?: Omit<Subtask, 'id'>[];
+	@ValidateNested({ each: true })
+	@Type(() => CreateSubtaskDto)
+	subtasks?: CreateSubtaskDto[];
 
 	@IsOptional()
 	@IsArray()
@@ -66,6 +71,7 @@ export class CreateTaskDto {
 	labelIds?: string[];
 
 	@IsOptional()
-	@IsObject()
-	metadata?: TaskMetadata;
+	@ValidateNested()
+	@Type(() => TaskMetadataDto)
+	metadata?: TaskMetadataDto;
 }

apps/todo/apps/backend/src/task/dto/metadata.dto.ts

@@ -0,0 +1,58 @@
+import {
+	IsString,
+	IsOptional,
+	IsNumber,
+	IsArray,
+	IsUUID,
+	IsEnum,
+	Min,
+	Max,
+	MaxLength,
+	ValidateNested,
+} from 'class-validator';
+import { Type } from 'class-transformer';
+
+export class EffectiveDurationDto {
+	@IsNumber()
+	@Min(1, { message: 'Dauer muss mindestens 1 sein' })
+	@Max(9999, { message: 'Dauer darf maximal 9999 sein' })
+	value: number;
+
+	@IsEnum(['minutes', 'hours', 'days'], { message: 'Ungültige Zeiteinheit' })
+	unit: 'minutes' | 'hours' | 'days';
+}
+
+export class TaskMetadataDto {
+	@IsOptional()
+	@IsString()
+	@MaxLength(10000, { message: 'Notizen dürfen maximal 10000 Zeichen haben' })
+	notes?: string;
+
+	@IsOptional()
+	@IsArray()
+	@IsString({ each: true })
+	@MaxLength(500, { each: true })
+	attachments?: string[];
+
+	@IsOptional()
+	@IsUUID()
+	linkedCalendarEventId?: string | null;
+
+	@IsOptional()
+	@IsNumber()
+	@IsEnum([1, 2, 3, 5, 8, 13, 21], {
+		message: 'Storypoints müssen Fibonacci-Zahlen sein (1,2,3,5,8,13,21)',
+	})
+	storyPoints?: number | null;
+
+	@IsOptional()
+	@ValidateNested()
+	@Type(() => EffectiveDurationDto)
+	effectiveDuration?: EffectiveDurationDto | null;
+
+	@IsOptional()
+	@IsNumber()
+	@Min(1, { message: 'Spaß-Faktor muss mindestens 1 sein' })
+	@Max(10, { message: 'Spaß-Faktor darf maximal 10 sein' })
+	funRating?: number | null;
+}

apps/todo/apps/backend/src/task/dto/subtask.dto.ts

@@ -0,0 +1,48 @@
+import {
+	IsString,
+	IsBoolean,
+	IsOptional,
+	IsNumber,
+	MinLength,
+	MaxLength,
+	Min,
+	IsDateString,
+} from 'class-validator';
+
+export class SubtaskDto {
+	@IsOptional()
+	@IsString()
+	id?: string;
+
+	@IsString()
+	@MinLength(1, { message: 'Subtask-Titel darf nicht leer sein' })
+	@MaxLength(500, { message: 'Subtask-Titel darf maximal 500 Zeichen haben' })
+	title: string;
+
+	@IsBoolean()
+	isCompleted: boolean;
+
+	@IsOptional()
+	@IsDateString()
+	completedAt?: string | null;
+
+	@IsNumber()
+	@Min(0)
+	order: number;
+}
+
+export class CreateSubtaskDto {
+	@IsString()
+	@MinLength(1, { message: 'Subtask-Titel darf nicht leer sein' })
+	@MaxLength(500, { message: 'Subtask-Titel darf maximal 500 Zeichen haben' })
+	title: string;
+
+	@IsOptional()
+	@IsBoolean()
+	isCompleted?: boolean;
+
+	@IsOptional()
+	@IsNumber()
+	@Min(0)
+	order?: number;
+}

apps/todo/apps/backend/src/task/task.controller.ts

@@ -33,9 +33,13 @@ export class TaskController {
 	}
 
 	@Get('completed')
-	async getCompleted(@CurrentUser() user: CurrentUserData, @Query('limit') limit?: number) {
-		const tasks = await this.taskService.getCompletedTasks(user.userId, limit ?? 50);
-		return { tasks };
+	async getCompleted(
+		@CurrentUser() user: CurrentUserData,
+		@Query('limit') limit?: number,
+		@Query('offset') offset?: number
+	) {
+		const result = await this.taskService.getCompletedTasks(user.userId, limit ?? 50, offset ?? 0);
+		return result;
 	}
 
 	@Get(':id')

apps/todo/apps/backend/src/task/task.service.ts

@@ -1,5 +1,5 @@
 import { Injectable, Inject, NotFoundException } from '@nestjs/common';
-import { eq, and, or, gte, lte, ilike, asc, desc, isNull, SQL } from 'drizzle-orm';
+import { eq, and, or, gte, lte, ilike, asc, desc, isNull, SQL, sql } from 'drizzle-orm';
 import { RRule, RRuleSet, rrulestr } from 'rrule';
 import { DATABASE_CONNECTION } from '../db/database.module';
 import { type Database } from '../db/connection';
@@ -452,14 +452,35 @@ export class TaskService {
 		return this.loadTaskLabelsBatch(result);
 	}
 
-	async getCompletedTasks(userId: string, limit: number = 50): Promise<TaskWithLabels[]> {
-		const result = await this.db.query.tasks.findMany({
-			where: and(eq(tasks.userId, userId), eq(tasks.isCompleted, true)),
-			orderBy: [desc(tasks.completedAt)],
-			limit,
-		});
+	async getCompletedTasks(
+		userId: string,
+		limit: number = 50,
+		offset: number = 0
+	): Promise<{ tasks: TaskWithLabels[]; total: number; hasMore: boolean }> {
+		// Enforce max limit to prevent abuse
+		const safeLimit = Math.min(limit, 100);
 
-		return this.loadTaskLabelsBatch(result);
+		const [result, countResult] = await Promise.all([
+			this.db.query.tasks.findMany({
+				where: and(eq(tasks.userId, userId), eq(tasks.isCompleted, true)),
+				orderBy: [desc(tasks.completedAt)],
+				limit: safeLimit,
+				offset,
+			}),
+			this.db
+				.select({ count: sql<number>`count(*)::int` })
+				.from(tasks)
+				.where(and(eq(tasks.userId, userId), eq(tasks.isCompleted, true))),
+		]);
+
+		const total = countResult[0]?.count ?? 0;
+		const tasksWithLabels = await this.loadTaskLabelsBatch(result);
+
+		return {
+			tasks: tasksWithLabels,
+			total,
+			hasMore: offset + safeLimit < total,
+		};
 	}
 
 	async reorder(

apps/todo/apps/web/src/routes/(app)/+layout.svelte

@@ -215,16 +215,20 @@
 	function handleModeChange(isSidebar: boolean) {
 		isSidebarMode = isSidebar;
 		sidebarModeStore.set(isSidebar);
-		if (typeof localStorage !== 'undefined') {
-			localStorage.setItem('todo-nav-sidebar', String(isSidebar));
+		try {
+			localStorage?.setItem('todo-nav-sidebar', String(isSidebar));
+		} catch {
+			// localStorage not available or quota exceeded
 		}
 	}
 
 	function handleCollapsedChange(collapsed: boolean) {
 		isCollapsed = collapsed;
 		collapsedStore.set(collapsed);
-		if (typeof localStorage !== 'undefined') {
-			localStorage.setItem('todo-nav-collapsed', String(collapsed));
+		try {
+			localStorage?.setItem('todo-nav-collapsed', String(collapsed));
+		} catch {
+			// localStorage not available or quota exceeded
 		}
 	}
 
@@ -263,18 +267,26 @@
 			goto(userSettings.startPage, { replaceState: true });
 		}
 
-		// Initialize sidebar mode from localStorage
-		const savedSidebar = localStorage.getItem('todo-nav-sidebar');
-		if (savedSidebar === 'true') {
-			isSidebarMode = true;
-			sidebarModeStore.set(true);
+		// Initialize sidebar mode from localStorage (with error handling for private browsing)
+		try {
+			const savedSidebar = localStorage?.getItem('todo-nav-sidebar');
+			if (savedSidebar === 'true') {
+				isSidebarMode = true;
+				sidebarModeStore.set(true);
+			}
+		} catch {
+			// localStorage not available (private browsing, quota exceeded, etc.)
 		}
 
 		// Initialize collapsed state from localStorage
-		const savedCollapsed = localStorage.getItem('todo-nav-collapsed');
-		if (savedCollapsed === 'true') {
-			isCollapsed = true;
-			collapsedStore.set(true);
+		try {
+			const savedCollapsed = localStorage?.getItem('todo-nav-collapsed');
+			if (savedCollapsed === 'true') {
+				isCollapsed = true;
+				collapsedStore.set(true);
+			}
+		} catch {
+			// localStorage not available
 		}
 
 		// Register Service Worker for PWA