Remove `onReplyCountClick` prop and use store method instead

Let `AnnotationHeader` call `store.setCollapsed` directly instead of
passing a callback down through several layers of components

src/sidebar/components/annotation-header.js

 import { createElement } from 'preact';
 import propTypes from 'prop-types';
 
+import useStore from '../store/use-store';
 import { isHighlight, isReply } from '../util/annotation-metadata';
 import { isPrivate } from '../util/permissions';
 
@@ -19,12 +20,13 @@ import Timestamp from './timestamp';
 export default function AnnotationHeader({
   annotation,
   isEditing,
-  onReplyCountClick,
   replyCount,
   showDocumentInfo,
   threadIsCollapsed,
 }) {
   const isCollapsedReply = isReply(annotation) && threadIsCollapsed;
+  const setCollapsed = useStore(store => store.setCollapsed);
+
   const annotationIsPrivate = isPrivate(
     annotation.permissions,
     annotation.user
@@ -34,7 +36,7 @@ export default function AnnotationHeader({
   // NB: `created` and `updated` are strings, not `Date`s
   const hasBeenEdited =
     annotation.updated && annotation.created !== annotation.updated;
-  const showTimestamp = !isEditing;
+  const showTimestamp = !isEditing && annotation.created;
   const showEditedTimestamp = hasBeenEdited && !isCollapsedReply;
 
   const replyPluralized = replyCount > 1 ? 'replies' : 'reply';
@@ -42,6 +44,8 @@ export default function AnnotationHeader({
   const showReplyButton = replyCount > 0 && isCollapsedReply;
   const showExtendedInfo = !isReply(annotation);
 
+  const onReplyCountClick = () => setCollapsed(annotation.id, false);
+
   return (
     <header className="annotation-header">
       <div className="annotation-header__row">
@@ -112,8 +116,6 @@ AnnotationHeader.propTypes = {
   annotation: propTypes.object.isRequired,
   /* Whether the annotation is actively being edited */
   isEditing: propTypes.bool,
-  /* Callback for when the toggle-replies element is clicked */
-  onReplyCountClick: propTypes.func.isRequired,
   /* How many replies this annotation currently has */
   replyCount: propTypes.number,
   /**

src/sidebar/components/annotation.js

@@ -22,7 +22,6 @@ import Button from './button';
 function Annotation({
   annotation,
   annotationsService,
-  onReplyCountClick,
   replyCount,
   showDocumentInfo,
   threadIsCollapsed,
@@ -101,7 +100,6 @@ function Annotation({
       <AnnotationHeader
         annotation={annotation}
         isEditing={isEditing}
-        onReplyCountClick={onReplyCountClick}
         replyCount={replyCount}
         showDocumentInfo={showDocumentInfo}
         threadIsCollapsed={threadIsCollapsed}
@@ -159,8 +157,6 @@ function Annotation({
 Annotation.propTypes = {
   annotation: propTypes.object.isRequired,
 
-  /** Callback for reply-count clicks */
-  onReplyCountClick: propTypes.func.isRequired,
   /** Number of replies to this annotation (thread) */
   replyCount: propTypes.number.isRequired,
   /** Should extended document info be rendered (e.g. in non-sidebar contexts)? */

src/sidebar/components/test/annotation-header-test.js

@@ -12,13 +12,13 @@ describe('AnnotationHeader', () => {
   let fakeIsHighlight;
   let fakeIsReply;
   let fakeIsPrivate;
+  let fakeStore;
 
   const createAnnotationHeader = props => {
     return mount(
       <AnnotationHeader
         annotation={fixtures.defaultAnnotation()}
         isEditing={false}
-        onReplyCountClick={sinon.stub()}
         replyCount={0}
         showDocumentInfo={false}
         threadIsCollapsed={false}
@@ -32,8 +32,13 @@ describe('AnnotationHeader', () => {
     fakeIsReply = sinon.stub().returns(false);
     fakeIsPrivate = sinon.stub();
 
+    fakeStore = {
+      setCollapsed: sinon.stub(),
+    };
+
     $imports.$mock(mockImportedComponents());
     $imports.$mock({
+      '../store/use-store': callback => callback(fakeStore),
       '../util/annotation-metadata': {
         isHighlight: fakeIsHighlight,
         isReply: fakeIsReply,
@@ -70,17 +75,30 @@ describe('AnnotationHeader', () => {
       wrapper.find('Button').filter('.annotation-header__reply-toggle');
 
     it('should render if annotation is a collapsed reply and there are replies to show', () => {
-      let fakeCallback = sinon.stub();
       fakeIsReply.returns(true);
       const wrapper = createAnnotationHeader({
-        onReplyCountClick: fakeCallback,
         replyCount: 1,
         threadIsCollapsed: true,
       });
 
       const btn = findReplyButton(wrapper);
       assert.isTrue(btn.exists());
-      assert.equal(btn.props().onClick, fakeCallback);
+    });
+
+    it('should expand replies when clicked', () => {
+      fakeIsReply.returns(true);
+      const fakeAnnotation = fixtures.defaultAnnotation();
+      const wrapper = createAnnotationHeader({
+        annotation: fakeAnnotation,
+        replyCount: 1,
+        threadIsCollapsed: true,
+      });
+
+      const btn = findReplyButton(wrapper);
+      btn.props().onClick();
+
+      assert.calledOnce(fakeStore.setCollapsed);
+      assert.calledWith(fakeStore.setCollapsed, fakeAnnotation.id, false);
     });
 
     it('should not render if there are no replies to show', () => {

src/sidebar/components/test/annotation-test.js

@@ -12,8 +12,6 @@ import Annotation from '../annotation';
 import { $imports } from '../annotation';
 
 describe('Annotation', () => {
-  let fakeOnReplyCountClick;
-
   // Dependency Mocks
   let fakeMetadata;
   let fakePermissions;
@@ -38,7 +36,6 @@ describe('Annotation', () => {
         annotation={fixtures.defaultAnnotation()}
         annotationsService={fakeAnnotationsService}
         toastMessenger={fakeToastMessenger}
-        onReplyCountClick={fakeOnReplyCountClick}
         replyCount={0}
         showDocumentInfo={false}
         threadIsCollapsed={true}
@@ -48,8 +45,6 @@ describe('Annotation', () => {
   };
 
   beforeEach(() => {
-    fakeOnReplyCountClick = sinon.stub();
-
     fakeAnnotationsService = {
       reply: sinon.stub(),
       save: sinon.stub().resolves(),

src/sidebar/components/thread.js

@@ -66,7 +66,6 @@ function Thread({ showDocumentInfo = false, thread, threadsService }) {
             <Annotation
               annotation={thread.annotation}
               replyCount={thread.replyCount}
-              onReplyCountClick={onToggleReplies}
               showDocumentInfo={showDocumentInfo}
               threadIsCollapsed={thread.collapsed}
             />