feat: add XML sitemap generation for SEO

.env.example

@@ -1,3 +1,6 @@
+# Site URL (used for sitemap generation and absolute URLs)
+NEXT_PUBLIC_SITE_URL=https://teachlink.app
+
 # Starknet Configuration
 NEXT_PUBLIC_STARKNET_NETWORK=goerli-alpha
 # NEXT_PUBLIC_STARKNET_RPC_URL=https://your-rpc-endpoint.com

package.json

@@ -21,7 +21,8 @@
     "check-i18n": "node scripts/check-i18n.cjs",
     "check-locales": "node scripts/check-locales.mjs",
     "prebuild": "npm run check-locales && npm run check-i18n",
-    "validate": "npm run validate:ui && npm run validate:web3"
+    "validate": "npm run validate:ui && npm run validate:web3",
+    "generate:sitemap": "npx tsx scripts/generate-sitemap.ts"
   },
   "dependencies": {
     "@dnd-kit/core": "^6.3.1",
@@ -39,10 +40,7 @@
     "class-variance-authority": "^0.7.1",
     "clsx": "^2.1.1",
     "date-fns": "^3.6.0",
-<<<<<<< HEAD
-=======
     "dompurify": "^3.2.4",
->>>>>>> bc54ed8 (clean: remove node_modules and reset repo)
     "framer-motion": "^12.23.0",
     "idb": "^8.0.0",
     "lucide-react": "^0.462.0",
@@ -57,20 +55,13 @@
     "react-hot-toast": "^2.6.0",
     "react-icons": "^5.5.0",
     "react-intersection-observer": "^10.0.3",
-<<<<<<< HEAD
-=======
     "react-virtualized-auto-sizer": "^1.0.7",
     "react-window": "^1.8.9",
->>>>>>> bc54ed8 (clean: remove node_modules and reset repo)
     "recharts": "^2.15.4",
     "socket.io-client": "^4.8.3",
     "tailwind-merge": "^2.6.0",
     "web-vitals": "^4.2.4",
     "workbox-webpack-plugin": "^7.0.0",
-<<<<<<< HEAD
-    "dompurify": "^3.2.4",
-=======
->>>>>>> bc54ed8 (clean: remove node_modules and reset repo)
     "zod": "^3.25.75",
     "zustand": "^5.0.10"
   },

scripts/generate-sitemap.ts

@@ -0,0 +1,94 @@
+/**
+ * Standalone sitemap generator — writes public/sitemap.xml at build time.
+ * Run with: npx tsx scripts/generate-sitemap.ts
+ */
+import { writeFileSync, mkdirSync } from 'fs';
+import { join } from 'path';
+
+const BASE_URL = process.env.NEXT_PUBLIC_SITE_URL ?? 'https://teachlink.app';
+
+interface SitemapEntry {
+  url: string;
+  lastModified?: Date;
+  changeFrequency?: 'always' | 'hourly' | 'daily' | 'weekly' | 'monthly' | 'yearly' | 'never';
+  priority?: number;
+}
+
+const STATIC_ROUTES: SitemapEntry[] = [
+  { url: BASE_URL, changeFrequency: 'daily', priority: 1.0 },
+  { url: `${BASE_URL}/search`, changeFrequency: 'weekly', priority: 0.8 },
+  { url: `${BASE_URL}/study-groups`, changeFrequency: 'weekly', priority: 0.7 },
+];
+
+async function fetchAllCourseIds(): Promise<string[]> {
+  const ids: string[] = [];
+  let cursor: string | undefined;
+
+  try {
+    do {
+      const url = new URL(`${BASE_URL}/api/courses`);
+      url.searchParams.set('limit', '100');
+      if (cursor) url.searchParams.set('cursor', cursor);
+
+      const res = await fetch(url.toString());
+      if (!res.ok) break;
+
+      const json = await res.json();
+      const page: { id: string }[] = Array.isArray(json) ? json : (json.data ?? []);
+      ids.push(...page.map((c) => c.id));
+      cursor = json.nextCursor;
+    } while (cursor);
+  } catch {
+    console.warn('Could not fetch courses — only static routes will be included.');
+  }
+
+  return ids;
+}
+
+function toXml(entries: SitemapEntry[]): string {
+  const now = new Date().toISOString().split('T')[0];
+
+  const urls = entries
+    .map(
+      (entry) => `
+  <url>
+    <loc>${entry.url}</loc>
+    <lastmod>${entry.lastModified ? entry.lastModified.toISOString().split('T')[0] : now}</lastmod>
+    ${entry.changeFrequency ? `<changefreq>${entry.changeFrequency}</changefreq>` : ''}
+    ${entry.priority !== undefined ? `<priority>${entry.priority.toFixed(1)}</priority>` : ''}
+  </url>`,
+    )
+    .join('');
+
+  return `<?xml version="1.0" encoding="UTF-8"?>
+<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
+${urls}
+</urlset>`;
+}
+
+async function main() {
+  const courseIds = await fetchAllCourseIds();
+
+  const courseRoutes: SitemapEntry[] = courseIds.map((id) => ({
+    url: `${BASE_URL}/courses/${id}`,
+    lastModified: new Date(),
+    changeFrequency: 'weekly',
+    priority: 0.8,
+  }));
+
+  const allEntries = [...STATIC_ROUTES, ...courseRoutes];
+  const xml = toXml(allEntries);
+
+  const publicDir = join(process.cwd(), 'public');
+  mkdirSync(publicDir, { recursive: true });
+
+  const outputPath = join(publicDir, 'sitemap.xml');
+  writeFileSync(outputPath, xml, 'utf-8');
+
+  console.log(`Sitemap written to ${outputPath} — ${allEntries.length} URL(s) included.`);
+}
+
+main().catch((err) => {
+  console.error('Sitemap generation failed:', err);
+  process.exit(1);
+});

src/app/sitemap.ts

@@ -0,0 +1,64 @@
+import type { MetadataRoute } from 'next';
+import type { Course, PaginatedResponse } from '@/types/api';
+
+const BASE_URL = process.env.NEXT_PUBLIC_SITE_URL ?? 'https://teachlink.app';
+
+export const revalidate = 3600; // regenerate every hour
+
+const STATIC_ROUTES: MetadataRoute.Sitemap = [
+  {
+    url: BASE_URL,
+    lastModified: new Date(),
+    changeFrequency: 'daily',
+    priority: 1.0,
+  },
+  {
+    url: `${BASE_URL}/search`,
+    lastModified: new Date(),
+    changeFrequency: 'weekly',
+    priority: 0.8,
+  },
+  {
+    url: `${BASE_URL}/study-groups`,
+    lastModified: new Date(),
+    changeFrequency: 'weekly',
+    priority: 0.7,
+  },
+];
+
+async function fetchAllCourses(): Promise<Course[]> {
+  const courses: Course[] = [];
+  let cursor: string | undefined;
+
+  try {
+    do {
+      const url = new URL(`${BASE_URL}/api/courses`);
+      url.searchParams.set('limit', '100');
+      if (cursor) url.searchParams.set('cursor', cursor);
+
+      const res = await fetch(url.toString(), { next: { revalidate: 3600 } });
+      if (!res.ok) break;
+
+      const json: PaginatedResponse<Course> = await res.json();
+      courses.push(...json.data);
+      cursor = json.nextCursor;
+    } while (cursor);
+  } catch {
+    // return whatever was collected before the failure
+  }
+
+  return courses;
+}
+
+export default async function sitemap(): Promise<MetadataRoute.Sitemap> {
+  const courses = await fetchAllCourses();
+
+  const courseRoutes: MetadataRoute.Sitemap = courses.map((course) => ({
+    url: `${BASE_URL}/courses/${course.id}`,
+    lastModified: new Date(),
+    changeFrequency: 'weekly',
+    priority: 0.8,
+  }));
+
+  return [...STATIC_ROUTES, ...courseRoutes];
+}