feat(SW-441): Implemented useScrollSpy hook

components/ContentType/HotelPage/Facilities/CardGrid/cardGrid.module.css

@@ -1,3 +1,7 @@
+.cardContainer {
+  scroll-margin-top: var(--hotel-page-scroll-margin-top);
+}
+
 .spanOne {
   grid-column: span 1;
 }

components/ContentType/HotelPage/Facilities/CardGrid/index.tsx

@@ -26,7 +26,7 @@ export default function FacilitiesCardGrid({
   }
 
   return (
-    <section id={imageCard.card.id}>
+    <section id={imageCard.card.id} className={styles.cardContainer}>
       <Grids.Stackable className={styles.desktopGrid}>
         {facilitiesCardGrid.map((card: FacilityCardType) => (
           <Card {...card} key={card.id} className={getCardClassName(card)} />

components/ContentType/HotelPage/Rooms/index.tsx

@@ -13,6 +13,7 @@ import { RoomCard } from "./RoomCard"
 
 import styles from "./rooms.module.css"
 
+import { HotelHashValues } from "@/types/components/hotelPage/tabNavigation"
 import type { RoomsProps } from "./types"
 
 export function Rooms({ rooms }: RoomsProps) {
@@ -50,8 +51,11 @@ export function Rooms({ rooms }: RoomsProps) {
   }
 
   return (
-    <SectionContainer id="rooms-section">
-      <div ref={scrollRef}></div>
+    <SectionContainer
+      id={HotelHashValues.rooms}
+      className={styles.roomsContainer}
+    >
+      <div ref={scrollRef} className={styles.scrollRef}></div>
       <SectionHeader
         textTransform="capitalize"
         title={intl.formatMessage({ id: "Rooms" })}

components/ContentType/HotelPage/Rooms/rooms.module.css

@@ -1,3 +1,13 @@
+.roomsContainer {
+  position: relative;
+  scroll-margin-top: var(--hotel-page-scroll-margin-top);
+}
+
+.scrollRef {
+  position: absolute;
+  top: calc(-1 * var(--hotel-page-scroll-margin-top));
+}
+
 .ctaContainer {
   display: flex;
   justify-content: center;

components/ContentType/HotelPage/TabNavigation/index.tsx

@@ -1,9 +1,11 @@
 "use client"
 import { useRouter } from "next/navigation"
+import { useEffect } from "react"
 import { useIntl } from "react-intl"
 
 import Link from "@/components/TempDesignSystem/Link"
 import useHash from "@/hooks/useHash"
+import useScrollSpy from "@/hooks/useScrollSpy"
 
 import styles from "./tabNavigation.module.css"
 
@@ -18,46 +20,58 @@ export default function TabNavigation({ restaurantTitle }: TabNavigationProps) {
   const router = useRouter()
   // const [isObserverActive, setIsObserverActive] = useState<boolean>(true)
 
-  const hotelTabLinks: { href: HotelHashValues | string; text: string }[] = [
+  const hotelTabLinks: { hash: HotelHashValues | string; text: string }[] = [
     {
-      href: HotelHashValues.overview,
+      hash: HotelHashValues.overview,
       text: intl.formatMessage({ id: "Overview" }),
     },
-    { href: HotelHashValues.rooms, text: intl.formatMessage({ id: "Rooms" }) },
+    { hash: HotelHashValues.rooms, text: intl.formatMessage({ id: "Rooms" }) },
     {
-      href: HotelHashValues.restaurant,
+      hash: HotelHashValues.restaurant,
       text: intl.formatMessage({ id: restaurantTitle }, { count: 1 }),
     },
     {
-      href: HotelHashValues.meetings,
+      hash: HotelHashValues.meetings,
       text: intl.formatMessage({ id: "Meetings & Conferences" }),
     },
     {
-      href: HotelHashValues.wellness,
+      hash: HotelHashValues.wellness,
       text: intl.formatMessage({ id: "Wellness & Exercise" }),
     },
     {
-      href: HotelHashValues.activities,
+      hash: HotelHashValues.activities,
       text: intl.formatMessage({ id: "Activities" }),
     },
-    { href: HotelHashValues.faq, text: intl.formatMessage({ id: "FAQ" }) },
+    { hash: HotelHashValues.faq, text: intl.formatMessage({ id: "FAQ" }) },
   ]
 
+  const { activeSectionId, pauseScrollSpy } = useScrollSpy(
+    hotelTabLinks.map(({ hash }) => hash)
+  )
+
+  useEffect(() => {
+    if (activeSectionId) {
+      router.replace(`#${activeSectionId}`, { scroll: false })
+    }
+  }, [activeSectionId, router])
+
   return (
     <div className={styles.stickyWrapper}>
       <nav className={styles.tabsContainer}>
         {hotelTabLinks.map((link) => {
           const isActive =
-            hash === link.href ||
-            (hash === "" && link.href === HotelHashValues.overview)
+            hash === link.hash ||
+            (!hash && link.hash === HotelHashValues.overview)
           return (
             <Link
-              key={link.href}
-              href={link.href}
+              key={link.hash}
+              href={`#${link.hash}`}
               active={isActive}
               variant="tab"
               color="burgundy"
               textDecoration="none"
+              scroll={true}
+              onClick={pauseScrollSpy}
             >
               {intl.formatMessage({ id: link.text })}
             </Link>

components/ContentType/HotelPage/hotelPage.module.css

@@ -1,4 +1,8 @@
 .pageContainer {
+  --hotel-page-navigation-height: 59px;
+  --hotel-page-scroll-margin-top: calc(
+    var(--hotel-page-navigation-height) + var(--Spacing-x2)
+  );
   display: grid;
   grid-template-areas:
     "hotelImages"
@@ -26,6 +30,7 @@
 .introContainer {
   display: grid;
   gap: var(--Spacing-x4);
+  scroll-margin-top: var(--hotel-page-scroll-margin-top);
 }
 
 @media screen and (min-width: 1367px) {

components/ContentType/HotelPage/index.tsx

@@ -21,6 +21,8 @@ import TabNavigation from "./TabNavigation"
 
 import styles from "./hotelPage.module.css"
 
+import { HotelHashValues } from "@/types/components/hotelPage/tabNavigation"
+
 export default async function HotelPage() {
   const intl = await getIntl()
   const lang = getLang()
@@ -63,7 +65,7 @@ export default async function HotelPage() {
         restaurantTitle={getRestaurantHeading(hotelDetailedFacilities)}
       />
       <main className={styles.mainSection}>
-        <div id="overview" className={styles.introContainer}>
+        <div id={HotelHashValues.overview} className={styles.introContainer}>
           <IntroSection
             hotelName={hotelName}
             hotelDescription={hotelDescription}

hooks/useHash.tsx

@@ -4,10 +4,13 @@ import { useParams } from "next/navigation"
 import { useEffect, useState } from "react"
 
 function getHash() {
-  return typeof window !== "undefined" ? window.location.hash : undefined
+  if (typeof window === "undefined" || !window.location.hash) {
+    return undefined
+  }
+  return window.location.hash.split("#")[1]
 }
 
-function useHash() {
+export default function useHash() {
   const [isClient, setIsClient] = useState(false)
   const [hash, setHash] = useState(getHash())
   const params = useParams()
@@ -19,5 +22,3 @@ function useHash() {
 
   return isClient ? hash : null
 }
-
-export default useHash

hooks/useScrollSpy.ts

@@ -0,0 +1,70 @@
+import { useCallback, useEffect, useMemo, useRef, useState } from "react"
+
+export default function useScrollSpy(
+  sectionIds: string[],
+  options: IntersectionObserverInit = {}
+): {
+  activeSectionId: string
+  pauseScrollSpy: () => void
+} {
+  const [activeSectionId, setActiveSectionId] = useState("")
+  const observerIsInactive = useRef(false)
+
+  const mergedOptions = useMemo(
+    () => ({
+      root: null,
+      // Make sure only to activate the section when it reaches the top of the viewport.
+      // A negative value for rootMargin shrinks the root bounding box inward,
+      // meaning elements will only be considered intersecting when they are further inside the viewport.
+      rootMargin: "-8% 0% -90% 0%",
+      threshold: 0,
+      ...options,
+    }),
+    [options]
+  )
+
+  const handleIntersection = useCallback(
+    (entries: IntersectionObserverEntry[]) => {
+      if (observerIsInactive.current) {
+        return
+      }
+
+      const intersectingEntries: IntersectionObserverEntry[] = []
+      entries.forEach((e) => {
+        if (e.isIntersecting) {
+          intersectingEntries.push(e)
+        }
+      })
+      if (intersectingEntries.length) {
+        setActiveSectionId(intersectingEntries[0].target.id)
+      }
+    },
+    []
+  )
+
+  useEffect(() => {
+    const observer = new IntersectionObserver(handleIntersection, mergedOptions)
+    const elements = sectionIds
+      .map((id) => document.getElementById(id))
+      .filter(Boolean)
+
+    elements.forEach((element) => {
+      if (!element) {
+        return
+      }
+      observer.observe(element)
+    })
+
+    return () => elements.forEach((el) => el && observer.unobserve(el))
+  }, [sectionIds, mergedOptions, handleIntersection])
+
+  const pauseScrollSpy = () => {
+    observerIsInactive.current = true
+
+    setTimeout(() => {
+      observerIsInactive.current = false
+    }, 500)
+  }
+
+  return { activeSectionId, pauseScrollSpy }
+}

types/components/hotelPage/tabNavigation.ts

@@ -1,11 +1,11 @@
-export enum HotelHashValues { // Should these be translated?
-  overview = "#overview",
-  rooms = "#rooms-section",
-  restaurant = "#restaurant-and-bar",
-  meetings = "#meetings-and-conferences",
-  wellness = "#wellness-and-exercise",
-  activities = "#activities",
-  faq = "#faq",
+export enum HotelHashValues {
+  overview = "overview",
+  rooms = "rooms-section",
+  restaurant = "restaurant-and-bar",
+  meetings = "meetings-and-conferences",
+  wellness = "wellness-and-exercise",
+  activities = "activities",
+  faq = "faq",
 }
 
 export type TabNavigationProps = {