perf: Lazy loading for links in topic sections (#127)

package.json

@@ -11,7 +11,7 @@
     "web"
   ],
   "dependencies": {
-    "jazz-nodejs": "^0.7.34",
+    "jazz-nodejs": "0.7.35-unique.2",
     "react-icons": "^5.3.0"
   },
   "devDependencies": {

web/components/routes/topics/detail/TopicDetailRoute.tsx

@@ -1,6 +1,6 @@
 "use client"
 
-import React from "react"
+import React, { useRef } from "react"
 import { TopicDetailHeader } from "./Header"
 import { TopicSections } from "./partials/topic-sections"
 import { useLinkNavigation } from "./use-link-navigation"
@@ -16,8 +16,10 @@ export const openPopoverForIdAtom = atom<string | null>(null)
 
 export function TopicDetailRoute({ topicName }: TopicDetailRouteProps) {
 	const { me } = useAccount({ root: { personalLinks: [] } })
-	const { topic, allLinks } = useTopicData(topicName)
-	const { activeIndex, setActiveIndex, containerRef, linkRefs } = useLinkNavigation(allLinks)
+	const { topic } = useTopicData(topicName, me)
+	// const { activeIndex, setActiveIndex, containerRef, linkRefs } = useLinkNavigation(allLinks)
+	const linksRefDummy = useRef<(HTMLLIElement | null)[]>([])
+	const containerRefDummy = useRef<HTMLDivElement>(null)
 
 	if (!topic || !me) {
 		return null
@@ -29,10 +31,10 @@ export function TopicDetailRoute({ topicName }: TopicDetailRouteProps) {
 			<TopicSections
 				topic={topic}
 				sections={topic.latestGlobalGuide?.sections}
-				activeIndex={activeIndex}
-				setActiveIndex={setActiveIndex}
-				linkRefs={linkRefs}
-				containerRef={containerRef}
+				activeIndex={0}
+				setActiveIndex={() => {}}
+				linkRefs={linksRefDummy}
+				containerRef={containerRefDummy}
 				me={me}
 				personalLinks={me.root.personalLinks}
 			/>

web/components/routes/topics/detail/partials/section.tsx

@@ -1,6 +1,8 @@
-import React from "react"
+import React, { useCallback, useEffect, useMemo, useRef, useState } from "react"
 import { LinkItem } from "./link-item"
 import { LaAccount, PersonalLinkLists, Section as SectionSchema, Topic, UserRoot } from "@/lib/schema"
+import { Skeleton } from "@/components/ui/skeleton"
+import { Loader2 } from "lucide-react"
 
 interface SectionProps {
 	topic: Topic
@@ -27,6 +29,12 @@ export function Section({
 	me,
 	personalLinks
 }: SectionProps) {
+	const [nLinksToLoad, setNLinksToLoad] = useState(10);
+
+	const linksToLoad = useMemo(() => {
+		return section.links?.slice(0, nLinksToLoad)
+	}, [section.links, nLinksToLoad])
+
 	return (
 		<div className="flex flex-col">
 			<div className="flex items-center gap-4 px-6 py-2 max-lg:px-4">
@@ -35,9 +43,9 @@ export function Section({
 			</div>
 
 			<div className="flex flex-col gap-px py-2">
-				{section.links?.map(
+				{linksToLoad?.map(
 					(link, index) =>
-						link?.url && (
+						link?.url ? (
 							<LinkItem
 								key={index}
 								topic={topic}
@@ -51,9 +59,52 @@ export function Section({
 								me={me}
 								personalLinks={personalLinks}
 							/>
+						) : (
+							<Skeleton key={index} className="h-14 xl:h-11 w-full" />
 						)
 				)}
+				{section.links?.length && section.links?.length > nLinksToLoad && (
+					<LoadMoreSpinner onLoadMore={() => setNLinksToLoad(n => n + 10)} />
+				)}
 			</div>
 		</div>
 	)
 }
+
+const LoadMoreSpinner = ({ onLoadMore }: { onLoadMore: () => void }) => {
+	const spinnerRef = useRef<HTMLDivElement>(null)
+
+	const handleIntersection = useCallback(
+		(entries: IntersectionObserverEntry[]) => {
+			const [entry] = entries
+			if (entry.isIntersecting) {
+				onLoadMore()
+			}
+		},
+		[onLoadMore]
+	)
+
+	useEffect(() => {
+		const observer = new IntersectionObserver(handleIntersection, {
+			root: null,
+			rootMargin: "0px",
+			threshold: 1.0,
+		})
+
+		if (spinnerRef.current) {
+			observer.observe(spinnerRef.current)
+		}
+
+		return () => {
+			if (spinnerRef.current) {
+				observer.unobserve(spinnerRef.current)
+			}
+		}
+	}, [handleIntersection])
+
+	return (
+		<div ref={spinnerRef} className="flex justify-center py-4">
+			<Loader2 className="h-6 w-6 animate-spin" />
+		</div>
+	)
+}

web/hooks/use-topic-data.ts

@@ -1,29 +1,15 @@
 import { useMemo } from "react"
 import { useCoState } from "@/lib/providers/jazz-provider"
 import { PublicGlobalGroup } from "@/lib/schema/master/public-group"
-import { ID } from "jazz-tools"
-import { Link } from "@/lib/schema"
+import { Account, ID } from "jazz-tools"
+import { Link, Topic } from "@/lib/schema"
 
 const GLOBAL_GROUP_ID = process.env.NEXT_PUBLIC_JAZZ_GLOBAL_GROUP as ID<PublicGlobalGroup>
 
-export function useTopicData(topicName: string) {
-	const group = useCoState(PublicGlobalGroup, GLOBAL_GROUP_ID, {
-		root: { topics: [] }
-	})
+export function useTopicData(topicName: string, me: Account | undefined) {
+	const topicID = useMemo(() => me && Topic.findUnique({topicName}, GLOBAL_GROUP_ID, me), [topicName, me])
 
-	// const topic = useCoState(Topic, "co_zS3TH4Lkj5MK9GEehinxhjjNTxB" as ID<Topic>, {})
-	const topic = useMemo(
-		() => group?.root.topics.find(topic => topic?.name === topicName),
-		[group?.root.topics, topicName]
-	)
+	const topic = useCoState(Topic, topicID, {latestGlobalGuide: {sections: [{links: []}]}})
 
-	const allLinks = useMemo(() => {
-		if (!topic?.latestGlobalGuide?.sections) return []
-
-		return topic.latestGlobalGuide.sections.flatMap(
-			section => section?.links?.filter((link): link is Link => !!link?.url) ?? []
-		)
-	}, [topic?.latestGlobalGuide?.sections])
-
-	return { topic, allLinks }
+	return { topic }
 }

web/lib/schema/index.ts

@@ -39,6 +39,8 @@ export class LaAccount extends Account {
 		// so just do default profile create provided by jazz-tools
 		super.migrate(creationProps)
 
+		console.log("In migration", this._refs.root, creationProps)
+
 		if (!this._refs.root && creationProps) {
 			this.root = UserRoot.create(
 				{

web/package.json

@@ -67,9 +67,9 @@
     "cmdk": "^1.0.0",
     "date-fns": "^3.6.0",
     "framer-motion": "^11.3.31",
-    "jazz-react": "0.7.35-new-auth.1",
+    "jazz-react": "0.7.35-unique.2",
     "jazz-react-auth-clerk": "0.7.33-new-auth.1",
-    "jazz-tools": "0.7.35-new-auth.0",
+    "jazz-tools": "0.7.35-unique.2",
     "jotai": "^2.9.3",
     "lowlight": "^3.1.0",
     "lucide-react": "^0.429.0",