1 files changed, 95 insertions, 0 deletions
diff --git a/app/assets/javascripts/image_diff/helpers/utils_helper.js b/app/assets/javascripts/image_diff/helpers/utils_helper.js
new file mode 100644
index 00000000000..96fc735e629
--- /dev/null
+++ b/app/assets/javascripts/image_diff/helpers/utils_helper.js
@@ -0,0 +1,95 @@
+import ImageBadge from '../image_badge';
+import ImageDiff from '../image_diff';
+import ReplacedImageDiff from '../replaced_image_diff';
+import '../../commit/image_file';
+
+export function resizeCoordinatesToImageElement(imageEl, meta) {
+  const { x, y, width, height } = meta;
+
+  const imageWidth = imageEl.width;
+  const imageHeight = imageEl.height;
+
+  const widthRatio = imageWidth / width;
+  const heightRatio = imageHeight / height;
+
+  return {
+    x: Math.round(x * widthRatio),
+    y: Math.round(y * heightRatio),
+    width: imageWidth,
+    height: imageHeight,
+  };
+}
+
+export function generateBadgeFromDiscussionDOM(imageFrameEl, discussionEl) {
+  const position = JSON.parse(discussionEl.dataset.position);
+  const firstNoteEl = discussionEl.querySelector('.note');
+  const badge = new ImageBadge({
+    actual: position,
+    imageEl: imageFrameEl.querySelector('img'),
+    noteId: firstNoteEl.id,
+    discussionId: discussionEl.dataset.discussionId,
+  });
+
+  return badge;
+}
+
+export function getTargetSelection(event) {
+  const containerEl = event.currentTarget;
+  const imageEl = containerEl.querySelector('img');
+
+  const x = event.offsetX;
+  const y = event.offsetY;
+
+  const width = imageEl.width;
+  const height = imageEl.height;
+
+  const actualWidth = imageEl.naturalWidth;
+  const actualHeight = imageEl.naturalHeight;
+
+  const widthRatio = actualWidth / width;
+  const heightRatio = actualHeight / height;
+
+  // Browser will include the frame as a clickable target,
+  // which would result in potential 1px out of bounds value
+  // This bound the coordinates to inside the frame
+  const normalizedX = Math.max(0, x) && Math.min(x, width);
+  const normalizedY = Math.max(0, y) && Math.min(y, height);
+
+  return {
+    browser: {
+      x: normalizedX,
+      y: normalizedY,
+      width,
+      height,
+    },
+    actual: {
+      // Round x, y so that we don't need to deal with decimals
+      x: Math.round(normalizedX * widthRatio),
+      y: Math.round(normalizedY * heightRatio),
+      width: actualWidth,
+      height: actualHeight,
+    },
+  };
+}
+
+export function initImageDiff(fileEl, canCreateNote, renderCommentBadge) {
+  const options = {
+    canCreateNote,
+    renderCommentBadge,
+  };
+  let diff;
+
+  // ImageFile needs to be invoked before initImageDiff so that badges
+  // can mount to the correct location
+  new gl.ImageFile(fileEl); // eslint-disable-line no-new
+
+  if (fileEl.querySelector('.diff-file .js-single-image')) {
+    diff = new ImageDiff(fileEl, options);
+    diff.init();
+  } else if (fileEl.querySelector('.diff-file .js-replaced-image')) {
+    diff = new ReplacedImageDiff(fileEl, options);
+    diff.init();
+  }
+
+  return diff;
+}