From 05fda6e0ed3fbdf88f8e5d9aaac4cef28d2b3078 Mon Sep 17 00:00:00 2001
From: AkiraFukushima <h3.poteto@gmail.com>
Date: Mon, 6 Jun 2022 23:14:00 +0900
Subject: [PATCH] refs #3301 Fix scrolling in DirectMessages

---
 .../Contents/DirectMessages.spec.ts           |  2 +
 .../Contents/DirectMessages.spec.ts           |  6 +++
 .../TimelineSpace/Contents/DirectMessages.vue | 54 ++++++++++++++++++-
 .../TimelineSpace/Contents/DirectMessages.ts  |  8 ++-
 4 files changed, 68 insertions(+), 2 deletions(-)

diff --git a/spec/renderer/integration/store/TimelineSpace/Contents/DirectMessages.spec.ts b/spec/renderer/integration/store/TimelineSpace/Contents/DirectMessages.spec.ts
index 3ee8091f..583847ea 100644
--- a/spec/renderer/integration/store/TimelineSpace/Contents/DirectMessages.spec.ts
+++ b/spec/renderer/integration/store/TimelineSpace/Contents/DirectMessages.spec.ts
@@ -135,6 +135,7 @@ let state = (): DirectMessagesState => {
   return {
     lazyLoading: false,
     heading: true,
+    scrolling: false,
     timeline: []
   }
 }
@@ -203,6 +204,7 @@ describe('Home', () => {
           return {
             lazyLoading: false,
             heading: true,
+            scrolling: false,
             timeline: [status1]
           }
         }
diff --git a/spec/renderer/unit/store/TimelineSpace/Contents/DirectMessages.spec.ts b/spec/renderer/unit/store/TimelineSpace/Contents/DirectMessages.spec.ts
index d66dc7e2..4d9cece6 100644
--- a/spec/renderer/unit/store/TimelineSpace/Contents/DirectMessages.spec.ts
+++ b/spec/renderer/unit/store/TimelineSpace/Contents/DirectMessages.spec.ts
@@ -139,6 +139,7 @@ describe('TimelineSpace/Contents/DirectMessages', () => {
           state = {
             lazyLoading: false,
             heading: true,
+            scrolling: false,
             timeline: [status2, status1]
           }
         })
@@ -153,6 +154,7 @@ describe('TimelineSpace/Contents/DirectMessages', () => {
           state = {
             lazyLoading: false,
             heading: true,
+            scrolling: false,
             timeline: [status2, rebloggedStatus]
           }
         })
@@ -170,6 +172,7 @@ describe('TimelineSpace/Contents/DirectMessages', () => {
             state = {
               lazyLoading: false,
               heading: true,
+              scrolling: false,
               timeline: [status2, status1]
             }
           })
@@ -184,6 +187,7 @@ describe('TimelineSpace/Contents/DirectMessages', () => {
             state = {
               lazyLoading: false,
               heading: true,
+              scrolling: false,
               timeline: [rebloggedStatus, status2, status1]
             }
           })
@@ -200,6 +204,7 @@ describe('TimelineSpace/Contents/DirectMessages', () => {
             state = {
               lazyLoading: false,
               heading: false,
+              scrolling: false,
               timeline: [status2, status1]
             }
           })
@@ -214,6 +219,7 @@ describe('TimelineSpace/Contents/DirectMessages', () => {
             state = {
               lazyLoading: false,
               heading: false,
+              scrolling: false,
               timeline: [rebloggedStatus, status2, status1]
             }
           })
diff --git a/src/renderer/components/TimelineSpace/Contents/DirectMessages.vue b/src/renderer/components/TimelineSpace/Contents/DirectMessages.vue
index 3558f1c3..cbd798e0 100644
--- a/src/renderer/components/TimelineSpace/Contents/DirectMessages.vue
+++ b/src/renderer/components/TimelineSpace/Contents/DirectMessages.vue
@@ -15,6 +15,7 @@
             @focusPrev="focusPrev"
             @focusRight="focusSidebar"
             @selectToot="focusToot(item)"
+            @sizeChanged="sizeChanged"
           >
           </toot>
         </DynamicScrollerItem>
@@ -30,6 +31,7 @@
 
 <script lang="ts">
 import { defineComponent, ref, computed, onMounted, onBeforeUpdate, onBeforeUnmount, onUnmounted, watch } from 'vue'
+import moment from 'moment'
 import { useStore } from '@/store'
 import { useI18next } from 'vue3-i18next'
 import { useRoute } from 'vue-router'
@@ -38,6 +40,7 @@ import { Entity } from 'megalodon'
 import useReloadable from '@/components/utils/reloadable'
 import Toot from '@/components/organisms/Toot.vue'
 import { EventEmitter } from '@/components/event'
+import { ScrollPosition } from '@/components/utils/scroll'
 import { ACTION_TYPES, MUTATION_TYPES } from '@/store/TimelineSpace/Contents/DirectMessages'
 import { MUTATION_TYPES as SIDE_MENU_MUTATION } from '@/store/TimelineSpace/SideMenu'
 import { MUTATION_TYPES as TIMELINE_MUTATION, ACTION_TYPES as TIMELINE_ACTION } from '@/store/TimelineSpace'
@@ -55,11 +58,16 @@ export default defineComponent({
     const { reloadable } = useReloadable(store, route, i18n)
 
     const focusedId = ref<string | null>(null)
+    const scrollPosition = ref<ScrollPosition | null>(null)
+    const observer = ref<ResizeObserver | null>(null)
+    const resizeTime = ref<moment.Moment | null>(null)
+    const scrollTime = ref<moment.Moment | null>(null)
     const scroller = ref<any>()
 
     const timeline = computed(() => store.state.TimelineSpace.Contents.DirectMessages.timeline)
     const lazyLoading = computed(() => store.state.TimelineSpace.Contents.DirectMessages.lazyLoading)
     const heading = computed(() => store.state.TimelineSpace.Contents.DirectMessages.heading)
+    const scrolling = computed(() => store.state.TimelineSpace.Contents.DirectMessages.scrolling)
     const openSideBar = computed(() => store.state.TimelineSpace.Contents.SideBar.openSideBar)
     const startReload = computed(() => store.state.TimelineSpace.HeaderMenu.reload)
     const unreadNotification = computed(() => store.state.TimelineSpace.timelineSetting.unreadNotification)
@@ -75,11 +83,27 @@ export default defineComponent({
           store.commit(`TimelineSpace/Contents/${CONTENTS_ACTION.CHANGE_LOADING}`, false)
         })
       }
+      const el = document.getElementById('scroller')
+      if (el) {
+        scrollPosition.value = new ScrollPosition(el)
+        scrollPosition.value.prepare()
+        observer.value = new ResizeObserver(() => {
+          if (scrollPosition.value && !heading.value && !lazyLoading.value && !scrolling.value) {
+            resizeTime.value = moment()
+            scrollPosition.value?.restore()
+          }
+        })
+        const scrollWrapper = el.getElementsByClassName('vue-recycle-scroller__item-wrapper')[0]
+        observer.value.observe(scrollWrapper)
+      }
     })
     onBeforeUpdate(() => {
       if (store.state.TimelineSpace.SideMenu.unreadDirectMessagesTimeline && heading.value) {
         store.commit(`TimelineSpace/SideMenu/${SIDE_MENU_MUTATION.CHANGE_UNREAD_DIRECT_MESSAGES_TIMELINE}`, false)
       }
+      if (scrollPosition.value) {
+        scrollPosition.value.prepare()
+      }
     })
     onBeforeUnmount(() => {
       if (!unreadNotification.value.direct) {
@@ -113,6 +137,13 @@ export default defineComponent({
       store.dispatch(`TimelineSpace/${TIMELINE_ACTION.START_DIRECT_MESSAGES_STREAMING}`)
     }
     const onScroll = (event: Event) => {
+      if (moment().diff(resizeTime.value) < 500) {
+        return
+      }
+      scrollTime.value = moment()
+      if (!scrolling.value) {
+        store.commit(`${space}/${MUTATION_TYPES.CHANGE_SCROLLING}`, true)
+      }
       // for lazyLoading
       if (
         (event.target as HTMLElement)!.clientHeight + (event.target as HTMLElement)!.scrollTop >=
@@ -125,6 +156,12 @@ export default defineComponent({
             if (statuses === null) {
               return
             }
+            if (statuses.length > 0) {
+              store.commit(`${space}/${MUTATION_TYPES.CHANGE_SCROLLING}`, true)
+              setTimeout(() => {
+                store.commit(`${space}/${MUTATION_TYPES.CHANGE_SCROLLING}`, false)
+              }, 500)
+            }
           })
           .catch(() => {
             ElMessage({
@@ -139,6 +176,14 @@ export default defineComponent({
       } else if ((event.target as HTMLElement)!.scrollTop <= 10 && !heading.value) {
         store.commit(`${space}/${MUTATION_TYPES.CHANGE_HEADING}`, true)
       }
+
+      setTimeout(() => {
+        const now = moment()
+        if (now.diff(scrollTime.value) >= 150) {
+          scrollTime.value = null
+          store.commit(`${space}/${MUTATION_TYPES.CHANGE_SCROLLING}`, false)
+        }
+      }, 150)
     }
     const updateToot = (message: Entity.Status) => {
       store.commit(`${space}/${MUTATION_TYPES.UPDATE_TOOT}`, message)
@@ -178,6 +223,12 @@ export default defineComponent({
     const focusSidebar = () => {
       EventEmitter.emit('focus-sidebar')
     }
+    const sizeChanged = () => {
+      store.commit(`${space}/${MUTATION_TYPES.CHANGE_SCROLLING}`, true)
+      setTimeout(() => {
+        store.commit(`${space}/${MUTATION_TYPES.CHANGE_SCROLLING}`, false)
+      }, 500)
+    }
 
     return {
       timeline,
@@ -192,7 +243,8 @@ export default defineComponent({
       focusToot,
       openSideBar,
       heading,
-      upper
+      upper,
+      sizeChanged
     }
   }
 })
diff --git a/src/renderer/store/TimelineSpace/Contents/DirectMessages.ts b/src/renderer/store/TimelineSpace/Contents/DirectMessages.ts
index 3a8185d6..ff9b684d 100644
--- a/src/renderer/store/TimelineSpace/Contents/DirectMessages.ts
+++ b/src/renderer/store/TimelineSpace/Contents/DirectMessages.ts
@@ -5,12 +5,14 @@ import { RootState } from '@/store'
 export type DirectMessagesState = {
   lazyLoading: boolean
   heading: boolean
+  scrolling: boolean
   timeline: Array<Entity.Status>
 }
 
 const state = (): DirectMessagesState => ({
   lazyLoading: false,
   heading: true,
+  scrolling: false,
   timeline: []
 })
 
@@ -23,7 +25,8 @@ export const MUTATION_TYPES = {
   ARCHIVE_TIMELINE: 'archiveTimeline',
   CLEAR_TIMELINE: 'clearTimeline',
   UPDATE_TOOT: 'updateToot',
-  DELETE_TOOT: 'deleteToot'
+  DELETE_TOOT: 'deleteToot',
+  CHANGE_SCROLLING: 'changeScrolling'
 }
 
 const mutations: MutationTree<DirectMessagesState> = {
@@ -76,6 +79,9 @@ const mutations: MutationTree<DirectMessagesState> = {
         return toot.id !== id
       }
     })
+  },
+  [MUTATION_TYPES.CHANGE_SCROLLING]: (state, value: boolean) => {
+    state.scrolling = value
   }
 }