feat: implement endless scrolling

src/routes/+page.server.ts

@@ -3,7 +3,10 @@ import { aktis, ratings } from '$lib/server/db/schema';
 import { avg, eq } from 'drizzle-orm';
 import type { PageServerLoad } from './$types';
 
-export const load: PageServerLoad = async () => {
+export const load: PageServerLoad = async ({ url }) => {
+	const offset = Number(url.searchParams.get('offset')) || 0;
+	const limit = 20;
+
 	const a = await db
 		.select({
 			id: aktis.id,
@@ -14,7 +17,8 @@ export const load: PageServerLoad = async () => {
 		.from(aktis)
 		.leftJoin(ratings, eq(aktis.id, ratings.aktiId))
 		.groupBy(aktis.id, aktis.title, aktis.summary)
-		.limit(50);
+		.limit(limit)
+		.offset(offset);
 
 	return {
 		aktis: a.map((a) => ({ ...a, rating: a.rating ? parseFloat(a.rating) : undefined }))

src/routes/+page.svelte

@@ -1,12 +1,55 @@
 <script lang="ts">
 	import AktiCard from '$lib/components/akti/AktiCard.svelte';
 	import type { PageProps } from './$types';
+	import { Spinner } from 'flowbite-svelte';
 
 	let { data }: PageProps = $props();
+
+	let aktis = $state(data.aktis);
+	let offset = $state(data.aktis.length);
+	let loading = $state(false);
+	let hasMore = $state(data.aktis.length >= 20);
+
+	async function loadMore() {
+		if (loading || !hasMore) return;
+		loading = true;
+		const res = await fetch(`/api/aktis?offset=${offset}`);
+		const newAktis = await res.json();
+
+		if (newAktis.length < 20) {
+			hasMore = false;
+		}
+
+		aktis = [...aktis, ...newAktis];
+		offset += newAktis.length;
+		loading = false;
+	}
+
+	function infiniteScroll(node: HTMLElement) {
+		const observer = new IntersectionObserver((entries) => {
+			if (entries[0].isIntersecting) {
+				loadMore();
+			}
+		});
+		observer.observe(node);
+		return {
+			destroy() {
+				observer.disconnect();
+			}
+		};
+	}
 </script>
 
 <div class="grid gap-5 grid-cols-1 sm:grid-cols-2 lg:grid-cols-3 3xl:grid-cols-5">
-	{#each data.aktis as akti (akti.id)}
+	{#each aktis as akti (akti.id)}
 		<AktiCard {akti}></AktiCard>
 	{/each}
 </div>
+
+<div class="mt-10 flex justify-center h-20">
+	{#if loading}
+		<Spinner />
+	{:else if hasMore}
+		<div use:infiniteScroll></div>
+	{/if}
+</div>

src/routes/api/aktis/+server.ts

@@ -0,0 +1,24 @@
+import { db } from '$lib/server/db';
+import { aktis, ratings } from '$lib/server/db/schema';
+import { avg, eq } from 'drizzle-orm';
+import { json, type RequestHandler } from '@sveltejs/kit';
+
+export const GET: RequestHandler = async ({ url }) => {
+	const offset = Number(url.searchParams.get('offset')) || 0;
+	const limit = 20;
+
+	const a = await db
+		.select({
+			id: aktis.id,
+			title: aktis.title,
+			summary: aktis.summary,
+			rating: avg(ratings.rating)
+		})
+		.from(aktis)
+		.leftJoin(ratings, eq(aktis.id, ratings.aktiId))
+		.groupBy(aktis.id, aktis.title, aktis.summary)
+		.limit(limit)
+		.offset(offset);
+
+	return json(a.map((a) => ({ ...a, rating: a.rating ? parseFloat(a.rating) : undefined })));
+};