Merge branch 'chat-fix-for-vertical-screen' into 'develop'

Chat scroll fix for vertical screen

Closes #997

See merge request pleroma/pleroma-fe!1277

CHANGELOG.md

@@ -20,6 +20,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 - Fixed multiple regressions in CSS styles
 - Fixed multiple issues with input fields when using CJK font as default
 - Fixed search field in navbar infringing into logo in some cases
+- Fixed not being able to load the chat history in vertical screens when the message list doesn't take the full height of the scrollable container on the first fetch.
 
 ### Changed
 - Clicking immediately when timeline shifts is now blocked to prevent misclicks

src/components/chat/chat.js

@@ -6,7 +6,7 @@ import PostStatusForm from '../post_status_form/post_status_form.vue'
 import ChatTitle from '../chat_title/chat_title.vue'
 import chatService from '../../services/chat_service/chat_service.js'
 import { promiseInterval } from '../../services/promise_interval/promise_interval.js'
-import { getScrollPosition, getNewTopPosition, isBottomedOut, scrollableContainerHeight } from './chat_layout_utils.js'
+import { getScrollPosition, getNewTopPosition, isBottomedOut, scrollableContainerHeight, isScrollable } from './chat_layout_utils.js'
 import { library } from '@fortawesome/fontawesome-svg-core'
 import {
   faChevronDown,
@@ -287,6 +287,14 @@ const Chat = {
               if (isFirstFetch) {
                 this.updateScrollableContainerHeight()
               }
+
+              // In vertical screens, the first batch of fetched messages may not always take the
+              // full height of the scrollable container.
+              // If this is the case, we want to fetch the messages until the scrollable container
+              // is fully populated so that the user has the ability to scroll up and load the history.
+              if (!isScrollable(this.$refs.scrollable) && messages.length > 0) {
+                this.fetchChat({ maxId: this.currentChatMessageService.minId })
+              }
             })
           })
         })

src/components/chat/chat_layout_utils.js

@@ -24,3 +24,10 @@ export const isBottomedOut = (el, offset = 0) => {
 export const scrollableContainerHeight = (inner, header, footer) => {
   return inner.offsetHeight - header.clientHeight - footer.clientHeight
 }
+
+// Returns whether or not the scrollbar is visible.
+export const isScrollable = (el) => {
+  if (!el) return
+
+  return el.scrollHeight > el.clientHeight
+}