test: add vitest and svelte testing library (resolves #13)

TODO.md

@@ -0,0 +1,65 @@
+# Project Review & Refactoring TODOs
+
+This document contains the prioritized list of refactoring tasks, architectural improvements, and testing strategies for the Aktiteil project.
+
+## 🚨 Must do (Security & Critical Best Practices)
+
+- [ ] **Fix Critical XSS Vulnerability (`{@html}` without sanitization)**
+  - **Where:** `src/routes/akti/[aktiId]/+page.svelte`
+  - **Why:** Rendering user input via `{@html data.akti.body}` without sanitization allows malicious scripts to be injected.
+  - **Fix:** Use the already installed `sanitize-html` library on the server to sanitize `changeRequest.body` before updating/inserting into the database.
+
+- [ ] **Move Server-Only Code to `$lib/server`**
+  - **Where:** `src/lib/auth.ts`
+  - **Why:** It imports from `./server/db`. Keeping server-side dependencies in the general `$lib` folder risks accidental imports by client components, breaking the Vite build and potentially leaking server logic.
+  - **Fix:** Move and rename it to `src/lib/server/session.ts` (or `authUtils.ts`) and update imports in `.server.ts` files.
+
+- [ ] **Fix Action Validation Error Handling**
+  - **Where:** `src/routes/akti/[aktiId]/+page.server.ts` and `src/routes/akti/[aktiId]/comment/+page.server.ts`
+  - **Why:** Currently returning `error(400)` on validation failure, which wipes form data and shows a generic error page.
+  - **Fix:** Use SvelteKit's `fail(400, { message: 'Invalid data' })` to keep the user on the page and preserve their input.
+
+- [ ] **Fix Hacky Fallback in Auth Query**
+  - **Where:** `src/lib/auth.ts` -> `getSession()`
+  - **Why:** Querying the DB with a fallback UUID (`eaf930...`) when email is missing is an anti-pattern.
+  - **Fix:** Implement an early return (`if (!session?.user?.email) return null;`) before hitting the database.
+
+## 🛠️ Should do (Performance & Architecture)
+
+- [ ] **Parallelize Database Queries**
+  - **Where:** `src/routes/akti/[aktiId]/+page.server.ts` (load function)
+  - **Why:** Queries are running sequentially.
+  - **Fix:** Use `Promise.all([ db.query.aktis.findFirst(...), db.query.ratings.findMany(...) ])` to run concurrently.
+
+- [ ] **Implement Pagination / Limit for the Dashboard**
+  - **Where:** `src/routes/+page.server.ts`
+  - **Why:** Querying all records joined with ratings will scale poorly.
+  - **Fix:** Add a `.limit()` clause and consider basic pagination or infinite scrolling.
+
+- [ ] **Extend Auth.js Types Globally**
+  - **Where:** `src/app.d.ts`
+  - **Why:** TypeScript doesn't inherently know `session.user.id` exists, leading to hacky workarounds.
+  - **Fix:** Override `@auth/sveltekit` Session types in `app.d.ts` to include `id` and `email` strictly.
+
+- [ ] **Consider Adopting a Form Library**
+  - **Where:** `src/lib/extractFormData.ts`
+  - **Why:** Custom form extractors lack instant client-side validation and seamless server-side error mapping.
+  - **Fix:** Consider switching to `sveltekit-superforms` which integrates well with Valibot.
+
+## ✨ Nice to have (UX & Polish)
+
+- [ ] **Clarify File Naming (`auth.ts` vs `auth.ts`)**
+  - Rename `src/lib/auth.ts` to `session.ts` or similar to distinguish from `src/auth.ts` (Auth.js setup).
+
+- [ ] **Abstract Heavy Database Queries**
+  - Move complex aggregations (like computing averages in `src/routes/+page.server.ts`) into a dedicated `src/lib/server/db/queries.ts` file to keep routes clean.
+
+- [ ] **Clean up Redundant Imports**
+  - In `src/routes/+layout.server.ts`, change `import { getSession as getSession }` to `import { getSession }`.
+
+## 🧪 Testing Plan
+
+- [ ] **Add Playwright (End-to-End Testing)**
+  - Install Playwright to test SvelteKit server actions, DB integration, and Flowbite forms holistically.
+- [ ] **Add Vitest + Svelte Testing Library (Unit/Component Testing)**
+  - Set up Vitest to test UI components (`AktiCard`, `AktiEditor`) and utility functions (`extractFormData`) in isolation.

package.json

@@ -10,6 +10,8 @@
 		"prepare": "husky",
 		"check": "svelte-kit sync && svelte-check --tsconfig ./tsconfig.json",
 		"check:watch": "svelte-kit sync && svelte-check --tsconfig ./tsconfig.json --watch",
+		"test": "vitest run",
+		"test:watch": "vitest",
 		"format": "prettier --write .",
 		"lint": "prettier --check . && eslint .",
 		"db:start": "docker compose up",
@@ -28,6 +30,8 @@
 		"@sveltejs/kit": "^2.49.0",
 		"@sveltejs/vite-plugin-svelte": "^6.2.1",
 		"@tailwindcss/vite": "^4.1.17",
+		"@testing-library/jest-dom": "^6.9.1",
+		"@testing-library/svelte": "^5.3.1",
 		"@tiptap/core": "3.7.2",
 		"@types/node": "^20.19.25",
 		"drizzle-kit": "^0.31.7",
@@ -39,6 +43,7 @@
 		"flowbite-svelte-icons": "^3.0.0",
 		"globals": "^16.5.0",
 		"husky": "^9.1.7",
+		"jsdom": "^29.0.1",
 		"lowlight": "^3.3.0",
 		"prettier": "^3.6.2",
 		"prettier-plugin-svelte": "^3.4.0",
@@ -47,7 +52,8 @@
 		"tailwindcss": "^4.1.17",
 		"typescript": "^5.9.3",
 		"typescript-eslint": "^8.47.0",
-		"vite": "^7.2.4"
+		"vite": "^7.2.4",
+		"vitest": "^4.1.2"
 	},
 	"dependencies": {
 		"@auth/drizzle-adapter": "^1.11.1",

src/lib/extractFormData.test.ts

@@ -0,0 +1,46 @@
+import { describe, it, expect } from 'vitest';
+import { extractFormData } from './extractFormData';
+import * as v from 'valibot';
+
+describe('extractFormData', () => {
+	it('should successfully extract and validate correct form data', async () => {
+		const formData = new FormData();
+		formData.append('name', 'John Doe');
+		formData.append('age', '30');
+
+		const request = new Request('http://localhost', {
+			method: 'POST',
+			body: formData
+		});
+
+		const schema = v.object({
+			name: v.string(),
+			age: v.string()
+		});
+
+		const result = await extractFormData(request, schema);
+
+		expect(result.error).toBeNull();
+		expect(result.data).toEqual({ name: 'John Doe', age: '30' });
+	});
+
+	it('should fail validation with missing required fields', async () => {
+		const formData = new FormData();
+		formData.append('age', '30');
+
+		const request = new Request('http://localhost', {
+			method: 'POST',
+			body: formData
+		});
+
+		const schema = v.object({
+			name: v.string(),
+			age: v.string()
+		});
+
+		const result = await extractFormData(request, schema);
+
+		expect(result.data).toBeUndefined();
+		expect(result.error).toBeTypeOf('string');
+	});
+});

vitest-setup.ts

@@ -0,0 +1 @@
+import '@testing-library/jest-dom/vitest';

vitest.config.ts

@@ -0,0 +1,12 @@
+import { defineConfig } from 'vitest/config';
+import { sveltekit } from '@sveltejs/kit/vite';
+import { svelteTesting } from '@testing-library/svelte/vite';
+
+export default defineConfig({
+	plugins: [sveltekit(), svelteTesting()],
+	test: {
+		include: ['src/**/*.{test,spec}.{js,ts}'],
+		environment: 'jsdom',
+		setupFiles: ['./vitest-setup.ts']
+	}
+});