Add revisions dialog (#485)

* Add mock files

Note that revisions-list needs to be called revisions in the reality to be confirm with the API spec, but our mocking solution doesn't allow that...

* Add revisions API calls

* Fix line endings in mock files

* Extend CommonModal to accept size and additionalClasses

* Clarify variable name in API request

* Add react-diff-viewer as dependency

* Add revision chooser modal

* Fix type of route params

* Added and updated mock files

* Added user-icon list per revision

* Added translation to alt text of avatars

* Updated mock file to remove inconsistencies

* Add caching for revisions

* Sort mock file revisions-list descending by timestamp

* Pre-select first/newest revision on first modal open

* Regenerated yarn.lock file from scratch

* Applied requested changes in variable names and line lengths

* User UserAvatar component instead of manually set image

* Move revision-modal-list-entry to own component

* Removed unnecessary return statements

src/components/editor/document-bar/revisions/utils.ts

@@ -0,0 +1,39 @@
+import { Revision } from '../../../../api/revisions'
+import { getUserById } from '../../../../api/users'
+import { UserResponse } from '../../../../api/users/types'
+
+const userResponseCache = new Map<string, UserResponse>()
+
+export const downloadRevision = (noteId: string, revision: Revision | null): void => {
+  if (!revision) {
+    return
+  }
+  const encoded = Buffer.from(revision.content).toString('base64')
+  const wrapper = document.createElement('a')
+  wrapper.download = `${noteId}-${revision.timestamp}.md`
+  wrapper.href = `data:text/markdown;charset=utf-8;base64,${encoded}`
+  document.body.appendChild(wrapper)
+  wrapper.click()
+  document.body.removeChild(wrapper)
+}
+
+export const getUserDataForRevision = (authors: string[]): UserResponse[] => {
+  const users: UserResponse[] = []
+  authors.forEach((author, index) => {
+    if (index > 9) {
+      return
+    }
+    const cacheEntry = userResponseCache.get(author)
+    if (cacheEntry) {
+      users.push(cacheEntry)
+      return
+    }
+    getUserById(author)
+      .then(userData => {
+        users.push(userData)
+        userResponseCache.set(author, userData)
+      })
+      .catch((error) => console.error(error))
+  })
+  return users
+}