Re-implemented image commenting on diffs

This re-implements image commenting in merge request diffs.
This feature was previously lost when the merge request
page was refactored into Vue.

With this, we create an overlay component. The overlay
component handles displaying the comment badges
and the comment form badge.
Badges are displayed based on the position attribute
sent with the discussion.

Comment forms for diff files are controlled through
a different state property. This is so we don't
tie comment forms to diff files directly creating
deep nested state. Instead we create a flat array
which holds the file hash & the X & Y position of
the comment form.

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/48956

1 files changed, 51 insertions, 32 deletions

diff --git a/app/assets/javascripts/vue_shared/components/content_viewer/viewers/image_viewer.vue b/app/assets/javascripts/vue_shared/components/content_viewer/viewers/image_viewer.vue
index 8163947cd0c..6f2f0f98690 100644
--- a/app/assets/javascripts/vue_shared/components/content_viewer/viewers/image_viewer.vue
+++ b/app/assets/javascripts/vue_shared/components/content_viewer/viewers/image_viewer.vue
@@ -17,19 +17,37 @@ export default {
       type: Boolean,
       default: true,
     },
+    innerCssClasses: {
+      type: [Array, Object, String],
+      required: false,
+      default: '',
+    },
   },
   data() {
     return {
       width: 0,
       height: 0,
-      isZoomable: false,
-      isZoomed: false,
+      isLoaded: false,
     };
   },
   computed: {
     fileSizeReadable() {
       return numberToHumanSize(this.fileSize);
     },
+    dimensionStyles() {
+      if (!this.isLoaded) return {};
+
+      return {
+        width: `${this.width}px`,
+        height: `${this.height}px`,
+      };
+    },
+    hasFileSize() {
+      return this.fileSize > 0;
+    },
+    hasDimensions() {
+      return this.width && this.height;
+    },
   },
   beforeDestroy() {
     window.removeEventListener('resize', this.resizeThrottled, false);
@@ -48,51 +66,52 @@ export default {
       const { contentImg } = this.$refs;
 
       if (contentImg) {
-        this.isZoomable =
-          contentImg.naturalWidth > contentImg.width ||
-          contentImg.naturalHeight > contentImg.height;
-
         this.width = contentImg.naturalWidth;
         this.height = contentImg.naturalHeight;
 
-        this.$emit('imgLoaded', {
-          width: this.width,
-          height: this.height,
-          renderedWidth: contentImg.clientWidth,
-          renderedHeight: contentImg.clientHeight,
+        this.$nextTick(() => {
+          this.isLoaded = true;
+
+          this.$emit('imgLoaded', {
+            width: this.width,
+            height: this.height,
+            renderedWidth: contentImg.clientWidth,
+            renderedHeight: contentImg.clientHeight,
+          });
         });
       }
     },
-    onImgClick() {
-      if (this.isZoomable) this.isZoomed = !this.isZoomed;
-    },
   },
 };
 </script>
 
 <template>
-  <div class="file-container">
-    <div class="file-content image_file">
+  <div>
+    <div
+      :class="innerCssClasses"
+      :style="dimensionStyles"
+      class="position-relative"
+    >
       <img
         ref="contentImg"
-        :class="{ 'is-zoomable': isZoomable, 'is-zoomed': isZoomed }"
         :src="path"
-        :alt="path"
         @load="onImgLoad"
-        @click="onImgClick"/>
-      <p
-        v-if="renderInfo"
-        class="file-info prepend-top-10">
-        <template v-if="fileSize>0">
-          {{ fileSizeReadable }}
-        </template>
-        <template v-if="fileSize>0 && width && height">
-          |
-        </template>
-        <template v-if="width && height">
-          W: {{ width }} | H: {{ height }}
-        </template>
-      </p>
+      />
+      <slot name="image-overlay"></slot>
     </div>
+    <p
+      v-if="renderInfo"
+      class="image-info"
+    >
+      <template v-if="hasFileSize">
+        {{ fileSizeReadable }}
+      </template>
+      <template v-if="hasFileSize && hasDimensions">
+        |
+      </template>
+      <template v-if="hasDimensions">
+        <strong>W</strong>: {{ width }} | <strong>H</strong>: {{ height }}
+      </template>
+    </p>
   </div>
 </template>