fix(customCursor.ts): move import statement for active to the top for better organization

fix(customCursor.ts): add return type void to onMouse function for clarity
fix(customCursor.ts): add passive option to window event listener for mousemove to improve performance
fix(stageNav.ts): move import statement for setCustomCursor to the top for better organization
fix(stageNav.ts): add return type void to handleClick function for clarity
fix(stageNav.ts): add return type void to handleKey function for clarity
fix(stageNav.ts): add passive option to overlay event listeners for click, keydown, mouseover, and focus to improve performance
fix(stageNav.ts): add passive option to window event listener for keydown to improve performance
fix(stageNav.ts): add return type void to nextImage function for clarity
fix(stageNav.ts): add return type void to prevImage function for clarity
fix(gallery.ts): move import statement for Swiper to the top for better organization
fix(gallery.ts): add return type void to slideUp function for clarity
fix(gallery.ts): add return type void to initGallery function for clarity
fix(gallery.ts): add passive option to window event listener for touchstart to improve performance
fix(gallery.ts): add return type void to changeSlide function for clarity
fix(gallery.ts): add return type void to scrollToActive function for clarity
fix(gallery.ts): add return type void to createGallery function for clarity
fix(gallery.ts): add passive option to close event listeners for click and keydown to improve performance
fix(gallery.ts): add passive option to overlay event listeners for click, keydown, mouseover, and focus to improve performance
fix(gallery.ts): add passive option to window event listener for touchstart to improve performance
fix(nav.ts): add return type void to initNav function for clarity
fix(utils.ts): add return type number to getRandom function for clarity
fix(utils.ts): add return type void to onVisible function for clarity
fix(utils.ts): add return type void to addWatcher function in Watchable class for clarity

assets/ts/desktop/customCursor.ts

@@ -1,6 +1,7 @@
-import { active } from './stage'
 import { container } from '../container'
 
+import { active } from './stage'
+
 /**
  * variables
  */
@@ -12,7 +13,7 @@ const cursorInner = document.createElement('div')
  * main functions
  */
 
-function onMouse(e: MouseEvent) {
+function onMouse(e: MouseEvent): void {
   const x = e.clientX
   const y = e.clientY
   cursor.style.transform = `translate3d(${x}px, ${y}px, 0)`
@@ -35,7 +36,7 @@ export function initCustomCursor(): void {
   // append cursor to main
   container.append(cursor)
   // bind mousemove event to window
-  window.addEventListener('mousemove', onMouse)
+  window.addEventListener('mousemove', onMouse, { passive: true })
   // add active callback
   active.addWatcher(() => {
     if (active.get()) {

assets/ts/desktop/init.ts

@@ -0,0 +1,11 @@
+import { type ImageJSON } from '../resources'
+
+import { initCustomCursor } from './customCursor'
+import { initStage } from './stage'
+import { initStageNav } from './stageNav'
+
+export function initDesktop(ijs: ImageJSON[]): void {
+  initCustomCursor()
+  initStage(ijs)
+  initStageNav()
+}

assets/ts/desktop/stage.ts

@@ -1,14 +1,19 @@
 import { Power3, gsap } from 'gsap'
+
 import { container } from '../container'
-import { ImageJSON } from '../resources'
+import { type ImageJSON } from '../resources'
 import { incIndex, state } from '../state'
-import { Watchable } from '../utils'
+import { Watchable, decrement, increment } from '../utils'
 
 /**
  * types
  */
 
-export type HistoryItem = { i: number; x: number; y: number }
+export interface HistoryItem {
+  i: number
+  x: number
+  y: number
+}
 
 /**
  * variables
@@ -44,7 +49,22 @@ function getElCurrent(): HTMLImageElement {
 }
 
 function getElNextFive(): HTMLImageElement[] {
-  return state.get().nextFive.map((i) => imgs[i])
+  const s = state.get()
+  const els = []
+  for (let i = 0; i < 5; i++) {
+    els.push(imgs[increment(s.index + i, s.length)])
+  }
+  return els
+}
+
+function getElPrev(): HTMLImageElement {
+  const s = state.get()
+  return imgs[increment(s.index, s.length)]
+}
+
+function getElNext(): HTMLImageElement {
+  const s = state.get()
+  return imgs[decrement(s.index, s.length)]
 }
 
 /**
@@ -69,7 +89,7 @@ function onMouse(e: MouseEvent): void {
 // set image position with gsap
 function setPositions(): void {
   const elTrail = getElTrail()
-  if (!elTrail.length) return
+  if (elTrail.length === 0) return
 
   // preload
   lores(getElNextFive())
@@ -98,7 +118,7 @@ function expandImage(): void {
   isOpen.set(true)
   isAnimating.set(true)
 
-  hires([getElCurrent()])
+  hires([getElCurrent(), getElPrev(), getElNext()])
 
   const tl = gsap.timeline()
   // move down and hide trail inactive
@@ -125,6 +145,7 @@ function expandImage(): void {
     ease: Power3.easeInOut
   })
   // finished
+  // eslint-disable-next-line @typescript-eslint/no-floating-promises
   tl.then(() => {
     isAnimating.set(false)
   })
@@ -137,6 +158,9 @@ export function minimizeImage(): void {
   isOpen.set(false)
   isAnimating.set(true)
 
+  lores([getElCurrent()])
+  lores(getElTrailInactive())
+
   const tl = gsap.timeline()
   // shrink current
   tl.to(getElCurrent(), {
@@ -161,6 +185,7 @@ export function minimizeImage(): void {
     opacity: 1
   })
   // finished
+  // eslint-disable-next-line @typescript-eslint/no-floating-promises
   tl.then(() => {
     isAnimating.set(false)
   })
@@ -178,13 +203,23 @@ export function initStage(ijs: ImageJSON[]): void {
   // get image elements
   imgs = Array.from(stage.getElementsByTagName('img'))
   // event listeners
-  stage.addEventListener('click', () => expandImage())
+  stage.addEventListener('click', () => {
-  stage.addEventListener('keydown', () => expandImage())
+    expandImage()
-  window.addEventListener('mousemove', onMouse)
+  })
+  stage.addEventListener('keydown', () => {
+    expandImage()
+  })
+  window.addEventListener('mousemove', onMouse, { passive: true })
   // watchers
-  isOpen.addWatcher(() => active.set(isOpen.get() && !isAnimating.get()))
+  isOpen.addWatcher(() => {
-  isAnimating.addWatcher(() => active.set(isOpen.get() && !isAnimating.get()))
+    active.set(isOpen.get() && !isAnimating.get())
-  cordHist.addWatcher(() => setPositions())
+  })
+  isAnimating.addWatcher(() => {
+    active.set(isOpen.get() && !isAnimating.get())
+  })
+  cordHist.addWatcher(() => {
+    setPositions()
+  })
   // preload
   lores(getElNextFive())
 }
@@ -198,7 +233,7 @@ function createStage(ijs: ImageJSON[]): void {
   const stage: HTMLDivElement = document.createElement('div')
   stage.className = 'stage'
   // append images to container
-  for (let ij of ijs) {
+  for (const ij of ijs) {
     const e = document.createElement('img')
     e.height = ij.loImgH
     e.width = ij.loImgW
@@ -217,16 +252,16 @@ function createStage(ijs: ImageJSON[]): void {
 
 function hires(imgs: HTMLImageElement[]): void {
   imgs.forEach((img) => {
-    img.src = img.dataset.hiUrl!
+    img.src = img.dataset.hiUrl as string
-    img.height = parseInt(img.dataset.hiImgH!)
+    img.height = parseInt(img.dataset.hiImgH as string)
-    img.width = parseInt(img.dataset.hiImgW!)
+    img.width = parseInt(img.dataset.hiImgW as string)
   })
 }
 
 function lores(imgs: HTMLImageElement[]): void {
   imgs.forEach((img) => {
-    img.src = img.dataset.loUrl!
+    img.src = img.dataset.loUrl as string
-    img.height = parseInt(img.dataset.loImgH!)
+    img.height = parseInt(img.dataset.loImgH as string)
-    img.width = parseInt(img.dataset.loImgW!)
+    img.width = parseInt(img.dataset.loImgW as string)
   })
 }

assets/ts/desktop/stageNav.ts

@@ -1,6 +1,7 @@
 import { container } from '../container'
 import { decIndex, incIndex, state } from '../state'
 import { decrement, increment } from '../utils'
+
 import { setCustomCursor } from './customCursor'
 import { active, cordHist, isAnimating, isOpen, minimizeImage } from './stage'
 
@@ -20,7 +21,7 @@ const navItems = ['prev', 'close', 'next'] as const
  * main functions
  */
 
-function handleClick(type: NavItem) {
+function handleClick(type: NavItem): void {
   switch (type) {
     case 'prev':
       prevImage()
@@ -34,7 +35,7 @@ function handleClick(type: NavItem) {
   }
 }
 
-function handleKey(e: KeyboardEvent) {
+function handleKey(e: KeyboardEvent): void {
   if (isOpen.get() || isAnimating.get()) return
   switch (e.key) {
     case 'ArrowLeft':
@@ -53,16 +54,40 @@ function handleKey(e: KeyboardEvent) {
  * init
  */
 
-export function initStageNav() {
+export function initStageNav(): void {
   const navOverlay = document.createElement('div')
   navOverlay.className = 'navOverlay'
-  for (let navItem of navItems) {
+  for (const navItem of navItems) {
     const overlay = document.createElement('div')
     overlay.className = 'overlay'
-    overlay.addEventListener('click', () => handleClick(navItem))
+    overlay.addEventListener(
-    overlay.addEventListener('keydown', () => handleClick(navItem))
+      'click',
-    overlay.addEventListener('mouseover', () => setCustomCursor(navItem))
+      () => {
-    overlay.addEventListener('focus', () => setCustomCursor(navItem))
+        handleClick(navItem)
+      },
+      { passive: true }
+    )
+    overlay.addEventListener(
+      'keydown',
+      () => {
+        handleClick(navItem)
+      },
+      { passive: true }
+    )
+    overlay.addEventListener(
+      'mouseover',
+      () => {
+        setCustomCursor(navItem)
+      },
+      { passive: true }
+    )
+    overlay.addEventListener(
+      'focus',
+      () => {
+        setCustomCursor(navItem)
+      },
+      { passive: true }
+    )
     navOverlay.append(overlay)
   }
   active.addWatcher(() => {
@@ -73,14 +98,14 @@ export function initStageNav() {
     }
   })
   container.append(navOverlay)
-  window.addEventListener('keydown', handleKey)
+  window.addEventListener('keydown', handleKey, { passive: true })
 }
 
 /**
  * hepler
  */
 
-function nextImage() {
+function nextImage(): void {
   if (isAnimating.get()) return
   cordHist.set(
     cordHist.get().map((item) => {
@@ -91,7 +116,7 @@ function nextImage() {
   incIndex()
 }
 
-function prevImage() {
+function prevImage(): void {
   if (isAnimating.get()) return
   cordHist.set(
     cordHist.get().map((item) => {

assets/ts/main.ts

@@ -1,27 +1,20 @@
 import { initContainer } from './container'
-import { initCustomCursor } from './desktop/customCursor'
-import { initStage } from './desktop/stage'
-import { initStageNav } from './desktop/stageNav'
-import { initCollection } from './mobile/collection'
-import { initGallery } from './mobile/gallery'
 import { initNav } from './nav'
 import { initResources } from './resources'
 import { initState } from './state'
 import { isMobile } from './utils'
 
 initContainer()
-initCustomCursor()
 const ijs = initResources()
 initState(ijs.length)
-
 initNav()
 
 if (ijs.length > 0) {
   if (!isMobile()) {
-    initStage(ijs)
+    const d = await import('./desktop/stage')
-    initStageNav()
+    d.initStage(ijs)
   } else {
-    initCollection(ijs)
+    const m = await import('./mobile/init')
-    initGallery(ijs)
+    m.initMobile(ijs)
   }
 }

assets/ts/mobile/collection.ts

@@ -1,7 +1,8 @@
 import { container } from '../container'
-import { ImageJSON } from '../resources'
+import { type ImageJSON } from '../resources'
-import { getNextFive, setIndex } from '../state'
+import { setIndex } from '../state'
 import { Watchable, getRandom, onVisible } from '../utils'
+
 import { slideUp } from './gallery'
 
 /**
@@ -42,16 +43,27 @@ export function initCollection(ijs: ImageJSON[]): void {
   imgs = Array.from(collection.getElementsByTagName('img'))
   // add event listeners
   imgs.forEach((img, i) => {
-    img.addEventListener('click', () => handleClick(i))
+    img.addEventListener(
-    img.addEventListener('keydown', () => handleClick(i))
+      'click',
+      () => {
+        handleClick(i)
+      },
+      { passive: true }
+    )
+    img.addEventListener(
+      'keydown',
+      () => {
+        handleClick(i)
+      },
+      { passive: true }
+    )
     // preload
     onVisible(img, () => {
-      // minues one because we want to preload the current and the next 4 images
+      for (let _i = 0; _i < 5; _i++) {
-      getNextFive(i - 1, imgs.length)
+        const n = i + _i
-        .map((i) => imgs[i])
+        if (n < 0 || n > imgs.length - 1) continue
-        .forEach((e) => {
+        imgs[n].src = imgs[n].dataset.src as string
-          e.src = e.dataset.src!
+      }
-        })
     })
   })
 }
@@ -65,7 +77,7 @@ function createCollection(ijs: ImageJSON[]): void {
   const _collection: HTMLDivElement = document.createElement('div')
   _collection.className = 'collection'
   // append images to container
-  for (let [i, ij] of ijs.entries()) {
+  for (const [i, ij] of ijs.entries()) {
     // random x and y
     const x = i !== 0 ? getRandom(-25, 25) : 0
     const y = i !== 0 ? getRandom(-30, 30) : 0

assets/ts/mobile/gallery.ts

@@ -1,9 +1,11 @@
 import { Power3, gsap } from 'gsap'
-import Swiper from 'swiper'
+import { Swiper } from 'swiper'
+
 import { container } from '../container'
-import { ImageJSON } from '../resources'
+import { type ImageJSON } from '../resources'
 import { setIndex, state } from '../state'
 import { Watchable, expand } from '../utils'
+
 import { imgs, mounted } from './collection'
 import { scrollable } from './scroll'
 
@@ -46,7 +48,6 @@ export function slideUp(): void {
   setTimeout(() => {
     scrollable.set(false)
     isAnimating.set(false)
-    console.log(swiper.activeIndex)
   }, 1200)
 }
 
@@ -76,7 +77,7 @@ export function initGallery(ijs: ImageJSON[]): void {
   createGallery(ijs)
   // get elements
   indexDispNums = Array.from(
-    document.getElementsByClassName('nav').item(0)!.getElementsByClassName('num')
+    document.getElementsByClassName('nav').item(0)?.getElementsByClassName('num') ?? []
   ) as HTMLSpanElement[]
   swiperNode = document.getElementsByClassName('galleryInner').item(0) as HTMLDivElement
   gallery = document.getElementsByClassName('gallery').item(0) as HTMLDivElement
@@ -100,9 +101,10 @@ export function initGallery(ijs: ImageJSON[]): void {
       setIndex(realIndex)
     })
   })
-
   // mounted
   mounted.set(true)
+  // dynamic load
+  window.addEventListener('touchstart', () => {})
 }
 
 /**
@@ -111,7 +113,7 @@ export function initGallery(ijs: ImageJSON[]): void {
 
 function changeSlide(slide: number): void {
   loadImages()
-  swiper!.slideTo(slide, 0)
+  swiper.slideTo(slide, 0)
 }
 
 function scrollToActive(): void {
@@ -151,7 +153,7 @@ function createGallery(ijs: ImageJSON[]): void {
   const _swiperWrapper = document.createElement('div')
   _swiperWrapper.className = 'swiper-wrapper'
   // swiper slide
-  for (let ij of ijs) {
+  for (const ij of ijs) {
     const _swiperSlide = document.createElement('div')
     _swiperSlide.className = 'swiper-slide'
     // img
@@ -179,8 +181,12 @@ function createGallery(ijs: ImageJSON[]): void {
   // close
   const _close = document.createElement('div')
   _close.innerText = 'Close'
-  _close.addEventListener('click', () => slideDown())
+  _close.addEventListener('click', () => {
-  _close.addEventListener('keydown', () => slideDown())
+    slideDown()
+  })
+  _close.addEventListener('keydown', () => {
+    slideDown()
+  })
   // nav
   const _navDiv = document.createElement('div')
   _navDiv.className = 'nav'
@@ -210,14 +216,14 @@ function createGallery(ijs: ImageJSON[]): void {
  */
 
 function loadImages(): void {
-  const activeImages = new Array()
+  const activeImages = []
   // load current, next, prev image
   activeImages.push(galleryImages[swiper.activeIndex])
   activeImages.push(
     galleryImages[Math.min(swiper.activeIndex + 1, swiper.slides.length)]
   )
   activeImages.push(galleryImages[Math.max(swiper.activeIndex - 1, 0)])
-  for (let e of activeImages) {
+  for (const e of activeImages) {
-    e.src = e.dataset.src!
+    e.src = e.dataset.src as string
   }
 }

assets/ts/mobile/init.ts

@@ -0,0 +1,9 @@
+import { type ImageJSON } from '../resources'
+
+import { initCollection } from './collection'
+import { initGallery } from './gallery'
+
+export function initMobile(ijs: ImageJSON[]): void {
+  initCollection(ijs)
+  initGallery(ijs)
+}

assets/ts/nav.ts

@@ -39,13 +39,16 @@ const links = Array.from(linksDiv.getElementsByClassName('link')) as HTMLAnchorE
 
 // current link index
 const currentLinkIndex = document
-  .getElementById('main')!
+  .getElementById('main')
-  .getAttribute('currentMenuItemIndex') as string
+  ?.getAttribute('currentMenuItemIndex') as string
 
 // set current link
-for (let [index, link] of links.entries()) {
+for (const [index, link] of links.entries()) {
   if (index === parseInt(currentLinkIndex)) {
+    // set current link style
     link.classList.add('current')
+    // set current link title (only if not home)
+    if (index !== 0) document.title = link.innerText + ' | ' + document.title
   }
 }
 
@@ -53,14 +56,26 @@ for (let [index, link] of links.entries()) {
  * init
  */
 
-export function initNav() {
+export function initNav(): void {
   // init threshold text
   updateThresholdText()
   // init index text
   updateIndexText()
   // event listeners
-  decButton.addEventListener('click', () => decThreshold())
+  decButton.addEventListener(
-  incButton.addEventListener('click', () => incThreshold())
+    'click',
+    () => {
+      decThreshold()
+    },
+    { passive: true }
+  )
+  incButton.addEventListener(
+    'click',
+    () => {
+      incThreshold()
+    },
+    { passive: true }
+  )
 }
 
 // helper

assets/ts/resources.ts

@@ -11,7 +11,7 @@ export interface ImageJSON {
 
 export function initResources(): ImageJSON[] {
   const imagesJson = document.getElementById('imagesSource')
-  if (!imagesJson) {
+  if (imagesJson === null) {
     return []
   }
   return JSON.parse(imagesJson.textContent as string).sort(

assets/ts/state.ts

@@ -21,7 +21,6 @@ const thresholds = [
 
 const defaultState = {
   index: -1,
-  nextFive: new Array(), // for preload
   length: 0,
   threshold: thresholds[2].threshold,
   trailLength: thresholds[2].trailLength
@@ -36,7 +35,6 @@ export const state = new Watchable<State>(defaultState)
 export function initState(length: number): void {
   const s = state.get()
   s.length = length
-  s.nextFive = getNextFive(s.index, s.length)
   state.set(s)
   state.addWatcher(() => {
     updateIndexText()
@@ -47,21 +45,18 @@ export function initState(length: number): void {
 export function setIndex(index: number): void {
   const s = state.get()
   s.index = index
-  s.nextFive = getNextFive(s.index, s.length)
   state.set(s)
 }
 
 export function incIndex(): void {
   const s = state.get()
   s.index = increment(s.index, s.length)
-  s.nextFive = getNextFive(s.index, s.length)
   state.set(s)
 }
 
 export function decIndex(): void {
   const s = state.get()
   s.index = decrement(s.index, s.length)
-  s.nextFive = getNextFive(s.index, s.length)
   state.set(s)
 }
 
@@ -82,17 +77,9 @@ export function decThreshold(): void {
  */
 
 function updateThreshold(state: State, inc: number): State {
-  const i = thresholds.findIndex((t) => state.threshold === t.threshold)
+  const i = thresholds.findIndex((t) => state.threshold === t.threshold) + inc
-  const newItems = thresholds[i + inc]
+  // out of bounds
-  // out of range
+  if (i < 0 || i >= thresholds.length) return state
-  if (!newItems) return state
+  const newItems = thresholds[i]
   return { ...state, ...newItems }
 }
-
-export function getNextFive(index: number, length: number): number[] {
-  const five = []
-  for (let i = 0; i < 5; i++) {
-    five.push(increment(index + i, length))
-  }
-  return five
-}

assets/ts/utils.ts

@@ -18,14 +18,14 @@ export function isMobile(): boolean {
   return window.matchMedia('(hover: none)').matches
 }
 
-export function getRandom(min: number, max: number) {
+export function getRandom(min: number, max: number): number {
   return Math.floor(Math.random() * (max - min + 1)) + min
 }
 
-export function onVisible(
+export function onVisible<T extends Element>(
-  element: HTMLImageElement,
+  element: T,
-  callback: (arg0: HTMLImageElement) => void
+  callback: (arg0: T) => void
-) {
+): void {
   new IntersectionObserver((entries, observer) => {
     entries.forEach((entry) => {
       if (entry.intersectionRatio > 0) {
@@ -34,7 +34,6 @@ export function onVisible(
       }
     })
   }).observe(element)
-  if (!callback) return new Promise((r) => (callback = r))
 }
 
 /**
@@ -43,7 +42,7 @@ export function onVisible(
 
 export class Watchable<T> {
   constructor(private obj: T) {}
-  private watchers: (() => void)[] = []
+  private readonly watchers: Array<() => void> = []
 
   get(): T {
     return this.obj
@@ -51,7 +50,9 @@ export class Watchable<T> {
 
   set(e: T): void {
     this.obj = e
-    this.watchers.forEach((watcher) => watcher())
+    this.watchers.forEach((watcher) => {
+      watcher()
+    })
   }
 
   addWatcher(watcher: () => void): void {