Improved image lazy loader

mixins/AnimeGrid.pixy

@@ -2,4 +2,4 @@ component AnimeGrid(animeList []*arn.Anime)
 	.anime-grid
 		each anime in animeList
 			a.anime-grid-cell.ajax(href="/anime/" + toString(anime.ID))
-				img.anime-grid-image(src=anime.Image.Small, alt=anime.Title.Romaji, title=anime.Title.Romaji + " (" + toString(anime.Rating.Overall) + ")")
+				img.anime-grid-image.lazy(data-src=anime.Image.Small, alt=anime.Title.Romaji, title=anime.Title.Romaji + " (" + toString(anime.Rating.Overall) + ")")

mixins/Avatar.pixy

@@ -4,7 +4,7 @@ component Avatar(user *arn.User)
 
 component AvatarNoLink(user *arn.User)
 	if user.HasAvatar()
-		img.user-image(src=user.SmallAvatar(), alt=user.Nick)
+		img.user-image.lazy(data-src=user.SmallAvatar(), alt=user.Nick)
 	else
 		SVGAvatar
 

pages/profile/profile.pixy

@@ -57,7 +57,7 @@ component Profile(viewUser *arn.User, user *arn.User, animeList *arn.AnimeList,
 			else
 				each item in animeList.Items
 					a.profile-watching-list-item.ajax(href=item.Anime().Link(), title=item.Anime().Title.Canonical + " (" + toString(item.Episodes) + " / " + arn.EpisodesToString(item.Anime().EpisodeCount) + ")")
-						img.anime-cover-image.profile-watching-list-item-image(src=item.Anime().Image.Tiny, alt=item.Anime().Title.Canonical)
+						img.anime-cover-image.profile-watching-list-item-image.lazy(data-src=item.Anime().Image.Tiny, alt=item.Anime().Title.Canonical)
 
 	.profile-category.mountable
 		h3

scripts/AnimeNotifier.ts

@@ -87,39 +87,34 @@ export class AnimeNotifier {
 				actions[actionName](this, element, e)
 			})
 
+			// Use "action assigned" flag instead of removing the class.
+			// This will make sure that DOM diffs which restore the class name
+			// will not assign the action multiple times to the same element.
 			element["action assigned"] = true
 		}
 	}
 
 	lazyLoadImages() {
-		for(let element of findAll("user-image")) {
-			this.lazyLoadImage(element as HTMLImageElement)
-		}
-
-		for(let element of findAll("anime-cover-image")) {
+		for(let element of findAll("lazy")) {
 			this.lazyLoadImage(element as HTMLImageElement)
 		}
 	}
 
 	lazyLoadImage(img: HTMLImageElement) {
-		// Prevent browser from loading it instantly
-		img["original source"] = img.src
-		img.src = ""
-
 		// Once the image becomes visible, load it
 		img["became visible"] = () => {
-			img.src = img["original source"]
+			img.src = img.dataset.src
 
 			if(img.naturalWidth === 0) {
 				img.onload = function() {
-					this.classList.add("user-image-found")
+					this.classList.add("image-found")
 				}
 
 				img.onerror = function() {
-					this.classList.add("user-image-not-found")
+					this.classList.add("image-not-found")
 				}
 			} else {
-				img.classList.add("user-image-found")
+				img.classList.add("image-found")
 			}
 		}
 

styles/grid.scarlet

@@ -32,6 +32,7 @@ mixin grid-image
 	height 100%
 	border-radius 3px
 	object-fit cover
+	default-transition
 
 mixin grid-icon
 	font-size 2.5rem

styles/images.scarlet

@@ -0,0 +1,11 @@
+.lazy
+	visibility hidden
+	opacity 0
+
+.image-found
+	visibility visible
+	opacity 1 !important
+
+.image-not-found
+	visibility hidden
+	opacity 0 !important

styles/user.scarlet

@@ -4,13 +4,6 @@
 	height avatar-size
 	border-radius 100%
 	object-fit cover
-	opacity 0
 	default-transition
 	:hover
-		box-shadow outline-shadow-heavy
-
-.user-image-found
-	opacity 1 !important
-
-.user-image-not-found
-	opacity 0 !important
+		box-shadow outline-shadow-heavy