feat: add loading indicator for desktop and mobile (#244)

* feat: add new CSS rule for hiding elements

- Add a new CSS rule for the class "hide" with a display property set to "none".

* feat: refactor image loading and navigation logic on desktop

- Add a line of code in `assets/ts/desktop/stage.ts` to reset the `src` of `elc` and add a class `hide` to it
- Add a line of code in `assets/ts/desktop/stage.ts` to call the `loader` function with `elc` as an argument
- Add a function `loader` in `assets/ts/desktop/stage.ts` to handle image loading and error events
- Modify the `initStageNav` function in `assets/ts/desktop/stageNav.ts` to watch the `isLoading` state and set custom cursor accordingly
- Modify the `initStageNav` function in `assets/ts/desktop/stageNav.ts` to handle close click events by calling the `handleClick` function and setting `isLoading` state to false
- Modify the `initStageNav` function in `assets/ts/desktop/stageNav.ts` to handle previous/next click events by calling the `handleClick` function only if `isLoading` is false
- Modify the `initStageNav` function in `assets/ts/desktop/stageNav.ts` to handle previous/next hover events by setting `loadedText` and updating custom cursor depending on `isLoading` state

* feat: refactor createGallery function and enhance loading functionality on mobile

- Add a loading text element to the gallery.scss file
- Add a loading indicator to the createGallery function in gallery.ts
- Modify the createGallery function in gallery.ts to hide the loading text element on image load
- Move the image element append logic to the parent container in the createGallery function in gallery.ts

* feat: update translations and add new loading translation in i18n files

* chore: remove css source map

* chore: modify build command to ignore css source map

* refactor: remove unnecessary style

* fix: fix desktop cursor text transition bug

assets/scss/_core/_base.scss

@@ -17,3 +17,7 @@ a,
 button {
   cursor: pointer;
 }
+
+.hide {
+  display: none;
+}

assets/scss/_partial/_gallery.scss

@@ -27,6 +27,18 @@
         height: 100%;
         object-fit: contain;
       }
+
+      .loadingText {
+        position: absolute;
+        top: 50%;
+        left: 50%;
+        transform: translate3d(-50%, -50%, 0);
+      }
+
+      .slideContainer {
+        position: relative;
+        display: inline-block;
+      }
     }
   }
 

assets/ts/desktop/stage.ts

@@ -25,6 +25,7 @@ export const cordHist = new Watchable<HistoryItem[]>([])
 export const isOpen = new Watchable<boolean>(false)
 export const isAnimating = new Watchable<boolean>(false)
 export const active = new Watchable<boolean>(false)
+export const isLoading = new Watchable<boolean>(false)
 
 let _gsap: typeof gsap
 let _Power3: typeof Power3
@@ -114,9 +115,13 @@ function setPositions(): void {
 
   if (isOpen.get()) {
     lores(getElTrail())
-    hires([getElCurrent(), getElPrev(), getElNext()])
+    const elc = getElCurrent()
+    elc.src = '' // reset src to ensure we only display hires images
+    elc.classList.add('hide')
+    hires([elc, getElPrev(), getElNext()])
     _gsap.set(imgs, { opacity: 0 })
-    _gsap.set(getElCurrent(), { opacity: 1, x: 0, y: 0, scale: 1 })
+    _gsap.set(elc, { opacity: 1, x: 0, y: 0, scale: 1 })
+    loader(elc)
   }
 }
 
@@ -127,7 +132,11 @@ function expandImage(): void {
   isOpen.set(true)
   isAnimating.set(true)
 
-  hires([getElCurrent(), getElPrev(), getElNext()])
+  const elc = getElCurrent()
+  // don't clear src here because we want a better transition
+
+  hires([elc, getElPrev(), getElNext()])
+  loader(elc)
 
   const tl = _gsap.timeline()
   // move down and hide trail inactive
@@ -292,3 +301,27 @@ function lores(imgs: HTMLImageElement[]): void {
     img.width = parseInt(img.dataset.loImgW as string)
   })
 }
+
+function loader(e: HTMLImageElement): void {
+  if (!e.complete) {
+    isLoading.set(true)
+    e.addEventListener(
+      'load',
+      () => {
+        isLoading.set(false)
+        e.classList.remove('hide')
+      },
+      { once: true, passive: true }
+    )
+    e.addEventListener(
+      'error',
+      () => {
+        isLoading.set(false)
+      },
+      { once: true, passive: true }
+    )
+  } else {
+    e.classList.remove('hide')
+    isLoading.set(false)
+  }
+}

assets/ts/desktop/stageNav.ts

@@ -3,7 +3,14 @@ import { decIndex, incIndex, state } from '../state'
 import { decrement, increment } from '../utils'
 
 import { setCustomCursor } from './customCursor'
-import { active, cordHist, isAnimating, isOpen, minimizeImage } from './stage'
+import {
+  active,
+  cordHist,
+  isAnimating,
+  isLoading,
+  isOpen,
+  minimizeImage
+} from './stage'
 
 /**
  * types
@@ -21,6 +28,8 @@ const navItems = [
   mainDiv.getAttribute('closeText') as string,
   mainDiv.getAttribute('nextText') as string
 ] as const
+const loadingText = (mainDiv.getAttribute('loadingText') as string) + '...'
+let loadedText = ''
 
 /**
  * main functions
@@ -56,39 +65,80 @@ function handleKey(e: KeyboardEvent): void {
  */
 
 export function initStageNav(): void {
+  // isLoading
+  isLoading.addWatcher((o) => {
+    if (o) setCustomCursor(loadingText)
+    else setCustomCursor(loadedText)
+  })
+  // navOverlay
   const navOverlay = document.createElement('div')
   navOverlay.className = 'navOverlay'
-  for (const navItem of navItems) {
+  for (const [index, navItem] of navItems.entries()) {
     const overlay = document.createElement('div')
     overlay.className = 'overlay'
-    overlay.addEventListener(
-      'click',
-      () => {
-        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 }
-    )
+    const isClose = index === 1
+    // close
+    if (isClose) {
+      overlay.addEventListener(
+        'click',
+        () => {
+          handleCloseClick(navItem)
+        },
+        { passive: true }
+      )
+      overlay.addEventListener(
+        'keydown',
+        () => {
+          handleCloseClick(navItem)
+        },
+        { passive: true }
+      )
+      overlay.addEventListener(
+        'mouseover',
+        () => {
+          handleCloseHover(navItem)
+        },
+        { passive: true }
+      )
+      overlay.addEventListener(
+        'focus',
+        () => {
+          handleCloseHover(navItem)
+        },
+        { passive: true }
+      )
+    }
+    // prev and next
+    else {
+      overlay.addEventListener(
+        'click',
+        () => {
+          handlePNClick(navItem)
+        },
+        { passive: true }
+      )
+      overlay.addEventListener(
+        'keydown',
+        () => {
+          handlePNClick(navItem)
+        },
+        { passive: true }
+      )
+      overlay.addEventListener(
+        'mouseover',
+        () => {
+          handlePNHover(navItem)
+        },
+        { passive: true }
+      )
+      overlay.addEventListener(
+        'focus',
+        () => {
+          handlePNHover(navItem)
+        },
+        { passive: true }
+      )
+    }
     navOverlay.append(overlay)
   }
   active.addWatcher(() => {
@@ -127,3 +177,23 @@ function prevImage(): void {
 
   decIndex()
 }
+
+function handleCloseClick(navItem: NavItem): void {
+  handleClick(navItem)
+  isLoading.set(false)
+}
+
+function handleCloseHover(navItem: NavItem): void {
+  loadedText = navItem
+  setCustomCursor(navItem)
+}
+
+function handlePNClick(navItem: NavItem): void {
+  if (!isLoading.get()) handleClick(navItem)
+}
+
+function handlePNHover(navItem: NavItem): void {
+  loadedText = navItem
+  if (isLoading.get()) setCustomCursor(loadingText)
+  else setCustomCursor(navItem)
+}

assets/ts/mobile/gallery.ts

@@ -196,14 +196,34 @@ function createGallery(ijs: ImageJSON[]): void {
   for (const ij of ijs) {
     const _swiperSlide = document.createElement('div')
     _swiperSlide.className = 'swiper-slide'
+    // loading indicator
+    const l = document.createElement('div')
+    l.className = 'loadingText'
+    l.innerText =
+      (document.getElementById('main')?.getAttribute('loadingText') as string) + '...'
     // img
     const e = document.createElement('img')
     e.dataset.src = ij.hiUrl
     e.height = ij.hiImgH
     e.width = ij.hiImgW
     e.alt = ij.alt
+    e.classList.add('hide')
+    // load event
+    e.addEventListener(
+      'load',
+      () => {
+        e.classList.remove('hide')
+        l.classList.add('hide')
+      },
+      { once: true, passive: true }
+    )
+    // parent container
+    const p = document.createElement('div')
+    p.className = 'slideContainer'
     // append
-    _swiperSlide.append(e)
+    p.append(e)
+    p.append(l)
+    _swiperSlide.append(p)
     _swiperWrapper.append(_swiperSlide)
   }
   // swiper node