improvements on fature/better-nsfw-image-loading

- loading indicator
- avoid hitting the cache if we already know the image was loaded
- more responsive toggle

src/components/attachment/attachment.js

@@ -11,7 +11,9 @@ const Attachment = {
     return {
       nsfwImage,
       hideNsfwLocal: this.$store.state.config.hideNsfw,
-      showHidden: false
+      showHidden: false,
+      loading: false,
+      img: document.createElement('img')
     }
   },
   computed: {
@@ -20,6 +22,13 @@ const Attachment = {
     },
     hidden () {
       return this.nsfw && this.hideNsfwLocal && !this.showHidden
+    },
+    autoHeight () {
+      if (this.type === 'image' && this.nsfw) {
+        return {
+          'min-height': '311px'
+        }
+      }
     }
   },
   methods: {
@@ -29,10 +38,15 @@ const Attachment = {
       }
     },
     toggleHidden () {
-      let img = document.createElement('img')
-      img.src = this.attachment.url
-      img.onload = () => {
-        this.showHidden = !this.showHidden
+      if (this.img.onload) {
+        this.img.onload()
+      } else {
+        this.loading = true
+        this.img.src = this.attachment.url
+        this.img.onload = () => {
+          this.loading = false
+          this.showHidden = !this.showHidden
+        }
       }
     }
   }