resolve choosing active comment logic

app/components/SimpleEditor/panes/Comments/CommentsProvider.js

@@ -74,6 +74,7 @@ class CommentsProvider extends TocProvider {
     }
 
     const activeComment = this.getActiveComment()
+    if (!activeComment) return this.removeActiveEntry()
 
     // current selection and previous selection both belong to the same comment
     if (activeEntry === activeComment.id) return
@@ -157,16 +158,46 @@ class CommentsProvider extends TocProvider {
   }
 
   getActiveComment () {
-    const commentAnnotations = this.getSelectionComments()
-    const commentState = this.getCommentState()
+    const comments = this.getSelectionComments()
+    const mode = this.getMode()
+    const selection = this.getSelection()
+
+    // we have a non-collapsed selection that contains multiple comments
+    if (mode === 'fuse') {
+      // only keep the comments that contain the whole selection
+      let annos = _.filter(comments, annotation => {
+        return annotation.getSelection().contains(selection)
+      })
+
+      if (annos.length === 0) return null
+      if (annos.length === 1) return annos[0]
+
+      // find comments that contain all other comments and remove them
+      // the focus of the active comment should be inwards
+      let remove = []
+      _.forEach(annos, anno => {
+        let removeIt = true
+
+        // TODO -- there's gotta be a better way to do this than a double loop
+        _.forEach(annos, innerAnno => {
+          if (anno === innerAnno) return
 
-    switch (commentState.mode) {
-      case 'fuse':
-        const count = commentAnnotations.length - 1
-        return commentAnnotations[count]
-      default:
-        return commentAnnotations[0]
+          const outerSelection = anno.getSelection()
+          const innerSelection = innerAnno.getSelection()
+          if (!outerSelection.contains(innerSelection)) removeIt = false
+        })
+
+        if (removeIt) remove.push(anno)
+      })
+
+      annos = _.difference(annos, remove)
+
+      // once you have all comments that do not contain each other wholly
+      // just choose the one on the left
+      return _.minBy(annos, 'startOffset')
     }
+
+    return comments[0]
   }
 
   // returns an array of all comments in selection
@@ -193,6 +224,11 @@ class CommentsProvider extends TocProvider {
     return commandStates.comment
   }
 
+  getMode () {
+    const commentState = this.getCommentState()
+    return commentState.mode
+  }
+
   getNode (id) {
     const doc = this.getDocument()
     return doc.get(id)