MiddleColumn: show similar channels after join channel (#4126)

src/api/gramjs/methods/chats.ts

@@ -2037,7 +2037,13 @@ export async function fetchChannelRecommendations({ chat }: { chat: ApiChat }) {
 
   updateLocalDb(result);
 
-  return result?.chats.map((_chat) => buildApiChatFromPreview(_chat)).filter(Boolean);
+  return {
+    similarChannels: result?.chats
+      .map((_chat) => buildApiChatFromPreview(_chat))
+      .filter(Boolean),
+    count:
+      result instanceof GramJs.messages.ChatsSlice ? result.count : undefined,
+  };
 }
 
 function handleUserPrivacyRestrictedUpdates(updates: GramJs.TypeUpdates) {

src/api/types/messages.ts

@@ -291,7 +291,14 @@ export interface ApiAction {
   text: string;
   targetUserIds?: string[];
   targetChatId?: string;
-  type: 'historyClear' | 'contactSignUp' | 'chatCreate' | 'topicCreate' | 'suggestProfilePhoto' | 'other';
+  type:
+  | 'historyClear'
+  | 'contactSignUp'
+  | 'chatCreate'
+  | 'topicCreate'
+  | 'suggestProfilePhoto'
+  | 'joinedChannel'
+  | 'other';
   photo?: ApiPhoto;
   amount?: number;
   currency?: string;

src/components/middle/ActionMessage.tsx

@@ -13,7 +13,7 @@ import type { FocusDirection, ThreadId } from '../../types';
 import type { PinnedIntersectionChangedCallback } from './hooks/usePinnedMessage';
 
 import {
-  getChatTitle, getMessageHtmlId, isChatChannel,
+  getChatTitle, getMessageHtmlId, isChatChannel, isJoinedChannelMessage,
 } from '../../global/helpers';
 import { getMessageReplyInfo } from '../../global/helpers/replies';
 import {
@@ -42,6 +42,7 @@ import useFocusMessage from './message/hooks/useFocusMessage';
 import AnimatedIconFromSticker from '../common/AnimatedIconFromSticker';
 import ActionMessageSuggestedAvatar from './ActionMessageSuggestedAvatar';
 import ContextMenuContainer from './message/ContextMenuContainer.async';
+import SimilarChannels from './message/SimilarChannels';
 
 type OwnProps = {
   message: ApiMessage;
@@ -129,6 +130,7 @@ const ActionMessage: FC<OwnProps & StateProps> = ({
   const isGift = Boolean(message.content.action?.text.startsWith('ActionGift'));
   const isGiftCode = Boolean(message.content.action?.text.startsWith('BoostingReceivedGift'));
   const isSuggestedAvatar = message.content.action?.type === 'suggestProfilePhoto' && message.content.action!.photo;
+  const isJoinedMessage = isJoinedChannelMessage(message);
 
   useEffect(() => {
     if (noAppearanceAnimation) {
@@ -291,15 +293,15 @@ const ActionMessage: FC<OwnProps & StateProps> = ({
       onMouseDown={handleMouseDown}
       onContextMenu={handleContextMenu}
     >
-      {!isSuggestedAvatar && !isGiftCode && <span className="action-message-content">{renderContent()}</span>}
+      {!isSuggestedAvatar && !isGiftCode && !isJoinedMessage && (
+        <span className="action-message-content">{renderContent()}</span>
+      )}
       {isGift && renderGift()}
       {isGiftCode && renderGiftCode()}
       {isSuggestedAvatar && (
-        <ActionMessageSuggestedAvatar
+        <ActionMessageSuggestedAvatar message={message} renderContent={renderContent} />
-          message={message}
-          renderContent={renderContent}
-        />
       )}
+      {isJoinedMessage && <SimilarChannels chatId={targetChatId!} />}
       {contextMenuPosition && (
         <ContextMenuContainer
           isOpen={isContextMenuOpen}

src/components/middle/MessageList.scss

@@ -219,6 +219,7 @@
     }
   }
 
+  .join-text,
   .sticky-date,
   .local-action-message,
   .ActionMessage,

src/components/middle/message/SimilarChannels.module.scss

@@ -0,0 +1,247 @@
+.root {
+  max-width: 45rem;
+  margin-top: 0.625rem;
+  position: relative;
+  --more-channel-background: #d8d8d8;
+  --more-channel-background-dark: #8f8f8f;
+  --more-channel-badge: #8f8f8f;
+  --more-channel-badge-overlay: #00000033;
+}
+
+.notch {
+  display: flex;
+  justify-content: center;
+  margin-top: 0.1875rem;
+}
+
+.notch-path {
+  fill: var(--color-background);
+}
+
+.join-text {
+  cursor: pointer;
+}
+
+.header {
+  padding: 0.375rem 0.375rem 0 0.75rem;
+  display: flex;
+  justify-content: space-between;
+  align-items: center;
+  position: sticky;
+  top: 0;
+  left: 0;
+}
+
+.title {
+  font-size: 0.875rem;
+  font-weight: 500;
+  line-height: 1.5rem;
+}
+
+.close {
+  width: auto;
+  height: auto;
+  font-size: 1.25rem;
+  padding: 0.125rem;
+  border-radius: 50%;
+
+  > .icon {
+    margin-left: 0.0625rem;
+  }
+}
+
+.skeleton {
+  height: 8.5rem;
+  border-radius: 0.9375rem;
+  margin-top: 0.625rem;
+}
+
+.inner {
+  background: var(--color-background);
+  border-radius: 0.9375rem;
+}
+
+.is-appearing {
+  animation: 0.15s ease-out channels-appear forwards;
+}
+
+.is-hiding {
+  animation: 0.15s ease-out channels-disappear forwards;
+}
+
+@keyframes channels-appear {
+  from {
+    transform: scale(0) translateY(-50%);
+    opacity: 0;
+    /* stylelint-disable-next-line plugin/no-low-performance-animation-properties */
+    height: 0;
+  }
+
+  to {
+    transform: none;
+    opacity: 1;
+    /* stylelint-disable-next-line plugin/no-low-performance-animation-properties */
+    height: 8.9375rem;
+  }
+}
+
+@keyframes channels-disappear {
+  from {
+    transform: none;
+    opacity: 1;
+    /* stylelint-disable-next-line plugin/no-low-performance-animation-properties */
+    height: 8.9375rem;
+  }
+
+  to {
+    transform: scale(0) translateY(-50%);
+    opacity: 0;
+    /* stylelint-disable-next-line plugin/no-low-performance-animation-properties */
+    height: 0;
+  }
+}
+
+.channel-list {
+  padding-bottom: 0.25rem;
+  padding-left: 0.25rem;
+  display: flex;
+  overflow-x: auto;
+  overflow-y: hidden;
+  white-space: nowrap;
+  border-bottom-left-radius: 0.9375rem;
+  border-bottom-right-radius: 0.9375rem;
+}
+
+.item {
+  height: 6.375rem;
+  position: relative;
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  margin-right: 0.5rem;
+  padding: 0.5rem 0.5rem 0.25rem 0.5rem;
+
+  &:not(:last-child) {
+    &:hover {
+      background: var(--color-chat-hover);
+      border-radius: 0.625rem;
+      cursor: pointer;
+    }
+  }
+}
+
+.last-item {
+  margin: 0;
+  padding: 0.5rem 0 0.25rem 0;
+  cursor: pointer;
+  min-width: 5rem;
+  margin-right: 0.75rem;
+  align-items: flex-start;
+}
+
+.avatar {
+  width: 3.75rem;
+  height: 3.75rem;
+}
+
+.last-item .avatar {
+  z-index: 3;
+  outline: 0.125rem solid var(--color-background);
+}
+
+.last-item .badge {
+  z-index: 4;
+  align-self: center;
+  background: var(--more-channel-background);
+
+  :global(.theme-dark) & {
+    background: var(--more-channel-background-dark);
+
+    &::before {
+      background-color: unset;
+    }
+  }
+}
+
+.badge {
+  max-width: 3.75rem;
+  height: 0.9375rem;
+  margin-top: -0.8125rem;
+  outline: 0.0625rem solid var(--color-background);
+  padding: 0.125rem 0.1875rem 0.125rem 0.25rem;
+  border-radius: 0.625rem;
+  z-index: 1;
+  display: flex;
+  justify-content: center;
+  align-items: center;
+  color: var(--color-white);
+  position: relative;
+
+  &::before {
+    content: "";
+    background-color: var(--more-channel-badge-overlay);
+    position: absolute;
+    max-width: 3.75rem;
+    width: 100%;
+    height: 0.9375rem;
+    border-radius: 0.625rem;
+    z-index: -1;
+  }
+}
+
+.icon {
+  font-size: 0.4375rem;
+  margin-right: 0.0625rem;
+}
+
+.members-count {
+  font-size: 0.5625rem;
+  font-weight: 700;
+  line-height: 0.6875rem;
+}
+
+.channel-title {
+  text-align: center;
+  height: 1.625rem;
+  font-size: 0.6875rem;
+  font-weight: 400;
+  line-height: 0.8125rem;
+  max-width: 3.4375rem;
+  margin-top: 0.125rem;
+  white-space: normal;
+  -webkit-line-clamp: 2;
+  -webkit-box-orient: vertical;
+  overflow: hidden;
+  text-overflow: ellipsis;
+  unicode-bidi: plaintext;
+}
+
+.last-item .channel-title {
+  color: var(--color-text-secondary);
+  align-self: center;
+}
+
+.fake-avatar {
+  border-radius: 50%;
+  width: 3.75rem;
+  height: 3.75rem;
+  position: absolute;
+  left: 0.625rem;
+  background: var(--more-channel-background);
+  outline: 0.125rem solid var(--color-background);
+  z-index: 2;
+
+  :global(.theme-dark) & {
+    background: var(--more-channel-background-dark);
+  }
+}
+
+.fake-avatar-inner {
+  width: 100%;
+  height: 100%;
+}
+
+.last-fake-avatar {
+  left: 1.25rem;
+  z-index: 1;
+}

src/components/middle/message/SimilarChannels.tsx

@@ -0,0 +1,266 @@
+import React, {
+  memo, useEffect, useMemo, useRef, useState,
+} from '../../../lib/teact/teact';
+import { getActions, getGlobal, withGlobal } from '../../../global';
+
+import type { ApiChat } from '../../../api/types';
+import { ApiMediaFormat } from '../../../api/types';
+
+import { getChatAvatarHash } from '../../../global/helpers';
+import {
+  selectChat,
+  selectIsCurrentUserPremium,
+  selectSimilarChannelIds,
+} from '../../../global/selectors';
+import buildClassName from '../../../util/buildClassName';
+import { getAverageColor, rgb2hex } from '../../../util/colors';
+import { formatIntegerCompact } from '../../../util/textFormat';
+
+import useFlag from '../../../hooks/useFlag';
+import useHorizontalScroll from '../../../hooks/useHorizontalScroll';
+import useLang from '../../../hooks/useLang';
+import useMedia from '../../../hooks/useMedia';
+import useTimeout from '../../../hooks/useTimeout';
+
+import Avatar from '../../common/Avatar';
+import Icon from '../../common/Icon';
+import Button from '../../ui/Button';
+import Skeleton from '../../ui/placeholder/Skeleton';
+
+import styles from './SimilarChannels.module.scss';
+
+const DEFAULT_BADGE_COLOR = '#3C3C4399';
+const SHOW_CHANNELS_NUMBER = 10;
+const MIN_SKELETON_DELAY = 300;
+const MAX_SKELETON_DELAY = 2000;
+
+type OwnProps = {
+  chatId: string;
+};
+
+type StateProps = {
+  similarChannelIds?: string[];
+  shouldShowInChat?: boolean;
+  count: number;
+  isCurrentUserPremium: boolean;
+};
+
+const SimilarChannels = ({
+  chatId,
+  similarChannelIds,
+  shouldShowInChat,
+  count,
+  isCurrentUserPremium,
+}: StateProps & OwnProps) => {
+  const lang = useLang();
+  const { toggleChannelRecommendations } = getActions();
+  const [isShowing, markShowing, markNotShowing] = useFlag(false);
+  const [isHiding, markHiding, markNotHiding] = useFlag(false);
+  // eslint-disable-next-line no-null/no-null
+  const ref = useRef<HTMLDivElement>(null);
+  const similarChannels = useMemo(() => {
+    if (!similarChannelIds) {
+      return undefined;
+    }
+
+    const global = getGlobal();
+    return similarChannelIds.map((id) => selectChat(global, id)).filter(Boolean);
+  }, [similarChannelIds]);
+  // Show skeleton while loading similar channels
+  const [shoulRenderSkeleton, setShoulRenderSkeleton] = useState(!similarChannelIds);
+  const firstSimilarChannels = useMemo(() => similarChannels?.slice(0, SHOW_CHANNELS_NUMBER), [similarChannels]);
+  const areSimilarChannelsPresent = Boolean(firstSimilarChannels?.length);
+  useHorizontalScroll(ref, !areSimilarChannelsPresent || !shouldShowInChat || shoulRenderSkeleton, true);
+  const isAnimating = isHiding || isShowing;
+  const shouldRenderChannels = Boolean(
+    !shoulRenderSkeleton
+      && (shouldShowInChat || isAnimating)
+      && areSimilarChannelsPresent,
+  );
+
+  useTimeout(() => setShoulRenderSkeleton(false), MAX_SKELETON_DELAY, []);
+
+  useEffect(() => {
+    if (shoulRenderSkeleton && similarChannels && shouldShowInChat) {
+      const id = setTimeout(() => {
+        setShoulRenderSkeleton(false);
+      }, MIN_SKELETON_DELAY);
+
+      return () => clearTimeout(id);
+    }
+
+    return undefined;
+  }, [similarChannels, shouldShowInChat, shoulRenderSkeleton]);
+
+  const handleToggle = () => {
+    toggleChannelRecommendations({ chatId });
+    if (shouldShowInChat) {
+      markNotShowing();
+      markHiding();
+    } else {
+      markShowing();
+      markNotHiding();
+    }
+  };
+
+  return (
+    <div className={buildClassName(styles.root)}>
+      <div className="join-text">
+        <span
+          className={buildClassName(areSimilarChannelsPresent && styles.joinText)}
+          onClick={areSimilarChannelsPresent ? handleToggle : undefined}
+        >
+          {lang('ChannelJoined')}
+        </span>
+      </div>
+      {shoulRenderSkeleton && <Skeleton className={styles.skeleton} />}
+      {shouldRenderChannels && (
+        <div
+          className={buildClassName(
+            isShowing && styles.isAppearing,
+            isHiding && styles.isHiding,
+          )}
+        >
+          <div className={styles.notch}>
+            <svg
+              width="19"
+              height="7"
+              viewBox="0 0 19 7"
+              fill="none"
+              xmlns="http://www.w3.org/2000/svg"
+            >
+              <path
+                className={styles.notchPath}
+                fill-rule="evenodd"
+                clip-rule="evenodd"
+                d="M19 7C16.8992 7 13.59 3.88897 11.5003 1.67424C10.7648 0.894688 10.397 0.50491 10.0434 0.385149C9.70568 0.270811 9.4225 0.270474 9.08456 0.38401C8.73059 0.50293 8.36133 0.892443 7.62279 1.67147C5.52303 3.88637 2.18302 7 0 7L19 7Z"
+                fill="white"
+              />
+            </svg>
+          </div>
+          <div className={styles.inner}>
+            <div className={styles.header}>
+              <span className={styles.title}>{lang('SimilarChannels')}</span>
+              <Button
+                className={styles.close}
+                color="translucent"
+                // eslint-disable-next-line react/jsx-no-bind
+                onClick={handleToggle}
+              >
+                <Icon name="close" />
+              </Button>
+            </div>
+            <div ref={ref} className={buildClassName(styles.channelList, 'no-scrollbar')}>
+              {firstSimilarChannels?.map((channel, i) => {
+                return i === SHOW_CHANNELS_NUMBER - 1 ? (
+                  <MoreChannels
+                    channel={channel}
+                    chatId={chatId}
+                    channelsCount={count - SHOW_CHANNELS_NUMBER + 1}
+                    isCurrentUserPremium={isCurrentUserPremium}
+                  />
+                ) : (
+                  <SimilarChannel channel={channel} />
+                );
+              })}
+            </div>
+          </div>
+        </div>
+      )}
+    </div>
+  );
+};
+
+function SimilarChannel({ channel }: { channel: ApiChat }) {
+  const { openChat } = getActions();
+  const color = useAverageColor(channel);
+
+  return (
+    <div className={styles.item} onClick={() => openChat({ id: channel.id })}>
+      <Avatar className={styles.avatar} key={channel.id} size="large" peer={channel} />
+      <div style={`background: ${color}`} className={styles.badge}>
+        <i className={buildClassName(styles.icon, 'icon icon-user-filled')} />
+        <span className={styles.membersCount}>{formatIntegerCompact(channel?.membersCount || 0)}
+        </span>
+      </div>
+      <span className={styles.channelTitle}>{channel.title}</span>
+    </div>
+  );
+}
+
+function MoreChannels({
+  channel,
+  chatId,
+  channelsCount,
+  isCurrentUserPremium,
+}: {
+  channel: ApiChat;
+  chatId: string;
+  channelsCount: number;
+  isCurrentUserPremium: boolean;
+}) {
+  const { openPremiumModal, openChatWithInfo } = getActions();
+  const lang = useLang();
+
+  const handleClickMore = () => {
+    if (isCurrentUserPremium) {
+      openChatWithInfo({
+        id: chatId, shouldReplaceHistory: true, profileTab: 'similarChannels', forceScrollProfileTab: true,
+      });
+    } else {
+      openPremiumModal();
+    }
+  };
+
+  return (
+    <div
+      className={buildClassName(styles.item, styles.lastItem)}
+      onClick={() => handleClickMore()}
+    >
+      <Avatar className={styles.avatar} key={channel.id} size="large" peer={channel} />
+      <div className={styles.fakeAvatar}>
+        <div className={styles.fakeAvatarInner} />
+      </div>
+      <div className={buildClassName(styles.fakeAvatar, styles.lastFakeAvatar)}>
+        <div className={styles.fakeAvatarInner} />
+      </div>
+      <div className={styles.badge}>
+        <span className={styles.membersCount}>{`+${channelsCount}`}</span>
+        {!isCurrentUserPremium && <Icon name="lock-badge" className={styles.icon} />}
+      </div>
+      <span className={styles.channelTitle}>{lang('MoreSimilar')}</span>
+    </div>
+  );
+}
+
+function useAverageColor(channel: ApiChat) {
+  const [color, setColor] = useState(DEFAULT_BADGE_COLOR);
+  const imgBlobUrl = useMedia(getChatAvatarHash(channel), false, ApiMediaFormat.BlobUrl);
+
+  useEffect(() => {
+    (async () => {
+      if (!imgBlobUrl) {
+        return;
+      }
+
+      const averageColor = await getAverageColor(imgBlobUrl);
+      setColor(`#${rgb2hex(averageColor)}`);
+    })();
+  }, [imgBlobUrl]);
+
+  return color;
+}
+
+export default memo(
+  withGlobal<OwnProps>((global, { chatId }): StateProps => {
+    const { similarChannelIds, shouldShowInChat, count } = selectSimilarChannelIds(global, chatId) || {};
+    const isCurrentUserPremium = selectIsCurrentUserPremium(global);
+
+    return {
+      similarChannelIds,
+      shouldShowInChat,
+      count,
+      isCurrentUserPremium,
+    };
+  })(SimilarChannels),
+);

src/components/right/Profile.tsx

@@ -125,6 +125,7 @@ type StateProps = {
   limitSimilarChannels: number;
   isTopicInfo?: boolean;
   isSavedDialog?: boolean;
+  forceScrollProfileTab?: boolean;
 };
 
 type TabProps = {
@@ -180,6 +181,7 @@ const Profile: FC<OwnProps & StateProps> = ({
   limitSimilarChannels,
   isTopicInfo,
   isSavedDialog,
+  forceScrollProfileTab,
 }) => {
   const {
     setLocalMediaSearchType,
@@ -254,10 +256,10 @@ const Profile: FC<OwnProps & StateProps> = ({
   }, [nextProfileTab, tabs]);
 
   useEffect(() => {
-    if (isChannel) {
+    if (isChannel && !similarChannels) {
       fetchChannelRecommendations({ chatId });
     }
-  }, [chatId, isChannel]);
+  }, [chatId, isChannel, similarChannels]);
 
   const renderingActiveTab = activeTab > tabs.length - 1 ? tabs.length - 1 : activeTab;
   const tabType = tabs[renderingActiveTab].type as ProfileTabType;
@@ -296,7 +298,13 @@ const Profile: FC<OwnProps & StateProps> = ({
 
   usePeerStoriesPolling(resultType === 'members' ? viewportIds as string[] : undefined);
 
-  const { handleScroll } = useProfileState(containerRef, resultType, profileState, onProfileStateChange);
+  const { handleScroll } = useProfileState(
+    containerRef,
+    resultType,
+    profileState,
+    onProfileStateChange,
+    forceScrollProfileTab,
+  );
 
   const { applyTransitionFix, releaseTransitionFix } = useTransitionFixes(containerRef);
 
@@ -693,7 +701,7 @@ export default memo(withGlobal<OwnProps>(
       && (getHasAdminRight(chat, 'inviteUsers') || !isUserRightBanned(chat, 'inviteUsers') || chat.isCreator);
     const canDeleteMembers = hasMembersTab && chat && (getHasAdminRight(chat, 'banUsers') || chat.isCreator);
     const activeDownloads = selectActiveDownloads(global, chatId);
-    const similarChannels = selectSimilarChannelIds(global, chatId);
+    const { similarChannelIds } = selectSimilarChannelIds(global, chatId) || {};
     const isCurrentUserPremium = selectIsCurrentUserPremium(global);
 
     let hasCommonChatsTab;
@@ -739,8 +747,9 @@ export default memo(withGlobal<OwnProps>(
       storyByIds,
       isChatProtected: chat?.isProtected,
       nextProfileTab: selectTabState(global).nextProfileTab,
+      forceScrollProfileTab: selectTabState(global).forceScrollProfileTab,
       shouldWarnAboutSvg: global.settings.byKey.shouldWarnAboutSvg,
-      similarChannels,
+      similarChannels: similarChannelIds,
       isCurrentUserPremium,
       isTopicInfo,
       isSavedDialog,

src/components/right/hooks/useProfileState.ts

@@ -20,10 +20,11 @@ export default function useProfileState(
   tabType: ProfileTabType,
   profileState: ProfileState,
   onProfileStateChange: (state: ProfileState) => void,
+  forceScrollProfileTab = false,
 ) {
   // Scroll to tabs if needed
   useEffectWithPrevDeps(([prevTabType]) => {
-    if (prevTabType && prevTabType !== tabType) {
+    if ((prevTabType && prevTabType !== tabType) || (tabType && forceScrollProfileTab)) {
       const container = containerRef.current!;
       const tabsEl = container.querySelector<HTMLDivElement>('.TabList')!;
       if (container.scrollTop < tabsEl.offsetTop) {
@@ -35,7 +36,7 @@ export default function useProfileState(
         }, PROGRAMMATIC_SCROLL_TIMEOUT_MS);
       }
     }
-  }, [tabType, onProfileStateChange, containerRef]);
+  }, [tabType, onProfileStateChange, containerRef, forceScrollProfileTab]);
 
   // Scroll to top
   useEffectWithPrevDeps(([prevProfileState]) => {

src/global/actions/api/chats.ts

@@ -44,6 +44,7 @@ import {
   isChatBasicGroup,
   isChatChannel,
   isChatSuperGroup,
+  isLocalMessageId,
   isUserBot,
   toChannelId,
 } from '../../helpers';
@@ -58,6 +59,7 @@ import {
   addUsers,
   addUserStatuses,
   addUsersToRestrictedInviteList,
+  deleteChatMessages,
   deleteTopic,
   leaveChat,
   removeChatFromChatLists,
@@ -67,6 +69,7 @@ import {
   replaceThreadParam,
   replaceUsers,
   replaceUserStatuses,
+  toggleSimilarChannels,
   updateChat,
   updateChatFullInfo,
   updateChatLastMessageId,
@@ -93,6 +96,7 @@ import {
   selectChatLastMessage,
   selectChatLastMessageId,
   selectChatListType,
+  selectChatMessages,
   selectCurrentChat,
   selectCurrentMessageList,
   selectDraft,
@@ -798,7 +802,7 @@ addActionHandler('deleteChat', (global, actions, payload): ActionReturnType => {
   void callApi('deleteChat', { chatId: chat.id });
 });
 
-addActionHandler('leaveChannel', (global, actions, payload): ActionReturnType => {
+addActionHandler('leaveChannel', async (global, actions, payload): Promise<void> => {
   const { chatId, tabId = getCurrentTabId() } = payload!;
   const chat = selectChat(global, chatId);
   if (!chat) {
@@ -814,7 +818,12 @@ addActionHandler('leaveChannel', (global, actions, payload): ActionReturnType =>
 
   const { id: channelId, accessHash } = chat;
   if (channelId && accessHash) {
-    void callApi('leaveChannel', { channelId, accessHash });
+    await callApi('leaveChannel', { channelId, accessHash });
+    global = getGlobal();
+    const chatMessages = selectChatMessages(global, chatId);
+    const localMessageIds = Object.keys(chatMessages).map(Number).filter(isLocalMessageId);
+    global = deleteChatMessages(global, chatId, localMessageIds);
+    setGlobal(global);
   }
 });
 
@@ -2615,9 +2624,9 @@ addActionHandler('fetchChannelRecommendations', async (global, actions, payload)
     return;
   }
 
-  const similarChannels = await callApi('fetchChannelRecommendations', {
+  const { similarChannels, count } = await callApi('fetchChannelRecommendations', {
     chat,
-  });
+  }) || {};
 
   if (!similarChannels) {
     return;
@@ -2625,8 +2634,19 @@ addActionHandler('fetchChannelRecommendations', async (global, actions, payload)
 
   global = getGlobal();
   global = addChats(global, buildCollectionByKey(similarChannels, 'id'));
-  global = addSimilarChannels(global, chatId, similarChannels.map((channel) => channel.id));
+  global = addSimilarChannels(global, chatId, similarChannels.map((channel) => channel.id), count);
+  setGlobal(global);
+});
 
+addActionHandler('toggleChannelRecommendations', (global, actions, payload): ActionReturnType => {
+  const { chatId } = payload;
+  const chat = selectChat(global, chatId);
+
+  if (!chat) {
+    return;
+  }
+
+  global = toggleSimilarChannels(global, chatId);
   setGlobal(global);
 });
 

src/global/actions/apiUpdaters/chats.ts

@@ -5,10 +5,13 @@ import { MAIN_THREAD_ID } from '../../../api/types';
 import { ARCHIVED_FOLDER_ID, MAX_ACTIVE_PINNED_CHATS } from '../../../config';
 import { buildCollectionByKey, omit } from '../../../util/iteratees';
 import { closeMessageNotifications, notifyAboutMessage } from '../../../util/notifications';
+import { buildLocalMessage } from '../../../api/gramjs/apiBuilders/messages';
+import { isChatChannel, isLocalMessageId } from '../../helpers';
 import {
   addActionHandler, getGlobal, setGlobal,
 } from '../../index';
 import {
+  deleteChatMessages,
   leaveChat,
   replaceThreadParam,
   updateChat,
@@ -23,7 +26,9 @@ import { updateTabState } from '../../reducers/tabs';
 import {
   selectChat,
   selectChatFullInfo,
+  selectChatLastMessageId,
   selectChatListType,
+  selectChatMessages,
   selectCommonBoxChatId,
   selectCurrentMessageList,
   selectIsChatListed,
@@ -87,6 +92,26 @@ addActionHandler('apiUpdate', (global, actions, update): ActionReturnType => {
 
     case 'updateChatJoin': {
       const listType = selectChatListType(global, update.id);
+      const chat = selectChat(global, update.id);
+      if (chat && isChatChannel(chat)) {
+        actions.fetchChannelRecommendations({ chatId: chat.id });
+        const lastMessageId = selectChatLastMessageId(global, chat.id);
+        const localMessage = buildLocalMessage(chat, lastMessageId);
+        localMessage.content.action = {
+          text: 'you joined this channel',
+          translationValues: ['ChannelJoined'],
+          type: 'joinedChannel',
+          targetChatId: chat.id,
+        };
+
+        actions.apiUpdate({
+          '@type': 'newMessage',
+          id: localMessage.id,
+          chatId: chat.id,
+          message: localMessage,
+        });
+      }
+
       if (!listType) {
         return undefined;
       }
@@ -95,7 +120,6 @@ addActionHandler('apiUpdate', (global, actions, update): ActionReturnType => {
       global = updateChat(global, update.id, { isNotJoined: false });
       setGlobal(global);
 
-      const chat = selectChat(global, update.id);
       if (chat) {
         actions.requestChatUpdate({ chatId: chat.id });
       }
@@ -104,7 +128,15 @@ addActionHandler('apiUpdate', (global, actions, update): ActionReturnType => {
     }
 
     case 'updateChatLeave': {
-      return leaveChat(global, update.id);
+      global = leaveChat(global, update.id);
+      const chat = selectChat(global, update.id);
+      if (chat && isChatChannel(chat)) {
+        const chatMessages = selectChatMessages(global, update.id);
+        const localMessageIds = Object.keys(chatMessages).map(Number).filter(isLocalMessageId);
+        global = deleteChatMessages(global, chat.id, localMessageIds);
+      }
+
+      return global;
     }
 
     case 'updateChatInbox': {

src/global/actions/ui/chats.ts

@@ -97,12 +97,13 @@ addActionHandler('openPreviousChat', (global, actions, payload): ActionReturnTyp
 });
 
 addActionHandler('openChatWithInfo', (global, actions, payload): ActionReturnType => {
-  const { profileTab, tabId = getCurrentTabId() } = payload;
+  const { profileTab, forceScrollProfileTab = false, tabId = getCurrentTabId() } = payload;
 
   global = updateTabState(global, {
     ...selectTabState(global, tabId),
     isChatInfoShown: true,
     nextProfileTab: profileTab,
+    forceScrollProfileTab,
   }, tabId);
   global = { ...global, lastIsChatInfoShown: true };
   setGlobal(global);

src/global/actions/ui/messages.ts

@@ -21,7 +21,7 @@ import { getServerTime } from '../../../util/serverTime';
 import { IS_TOUCH_ENV } from '../../../util/windowEnvironment';
 import versionNotification from '../../../versionNotification.txt';
 import {
-  getIsSavedDialog, getMessageSummaryText, getSenderTitle, isChatChannel,
+  getIsSavedDialog, getMessageSummaryText, getSenderTitle, isChatChannel, isJoinedChannelMessage,
 } from '../../helpers';
 import { renderMessageSummaryHtml } from '../../helpers/renderMessageSummaryHtml';
 import { addActionHandler, getGlobal, setGlobal } from '../../index';
@@ -330,6 +330,13 @@ addActionHandler('focusLastMessage', (global, actions, payload): ActionReturnTyp
       lastMessageId = pinnedMessageIds[pinnedMessageIds.length - 1];
     } else {
       lastMessageId = selectChatLastMessageId(global, chatId);
+
+      const chatMessages = selectChatMessages(global, chatId);
+      // Workaround for scroll to local message 'you joined this channel'
+      const lastChatMessage = Object.values(chatMessages).reverse()[0];
+      if (lastMessageId && isJoinedChannelMessage(lastChatMessage) && lastChatMessage.id > lastMessageId) {
+        lastMessageId = lastChatMessage.id;
+      }
     }
   } else if (isSavedDialog) {
     lastMessageId = selectChatLastMessageId(global, String(threadId), 'saved');

src/global/actions/ui/misc.ts

@@ -151,7 +151,7 @@ addActionHandler('resetNextProfileTab', (global, actions, payload): ActionReturn
     return undefined;
   }
 
-  return updateTabState(global, { nextProfileTab: undefined }, tabId);
+  return updateTabState(global, { nextProfileTab: undefined, forceScrollProfileTab: false }, tabId);
 });
 
 addActionHandler('toggleStatistics', (global, actions, payload): ActionReturnType => {

src/global/helpers/messages.ts

@@ -354,3 +354,7 @@ export function isExpiredMessage(message: ApiMessage) {
 export function hasMessageTtl(message: ApiMessage) {
   return message.content?.ttlSeconds !== undefined;
 }
+
+export function isJoinedChannelMessage(message: ApiMessage) {
+  return message.content.action && message.content.action.type === 'joinedChannel';
+}

src/global/reducers/chats.ts

@@ -446,7 +446,9 @@ export function deleteTopic<T extends GlobalState>(
 export function addSimilarChannels<T extends GlobalState>(
   global: T,
   chatId: string,
-  similarChannels: string[],
+  similarChannelIds: string[],
+  count?: number,
+  shouldShowInChat = true,
 ) {
   return {
     ...global,
@@ -454,7 +456,33 @@ export function addSimilarChannels<T extends GlobalState>(
       ...global.chats,
       similarChannelsById: {
         ...global.chats.similarChannelsById,
-        [chatId]: similarChannels,
+        [chatId]: {
+          similarChannelIds,
+          count: count || similarChannelIds.length,
+          shouldShowInChat,
+        },
+      },
+    },
+  };
+}
+
+export function toggleSimilarChannels<T extends GlobalState>(
+  global: T,
+  chatId: string,
+) {
+  const similarChannels = global.chats.similarChannelsById[chatId];
+  const shouldShowInChat = !global.chats.similarChannelsById[chatId].shouldShowInChat;
+
+  return {
+    ...global,
+    chats: {
+      ...global.chats,
+      similarChannelsById: {
+        ...global.chats.similarChannelsById,
+        [chatId]: {
+          ...similarChannels,
+          shouldShowInChat,
+        },
       },
     },
   };

src/global/selectors/chats.ts

@@ -325,7 +325,7 @@ export function selectRequestedChatTranslationLanguage<T extends GlobalState>(
 export function selectSimilarChannelIds<T extends GlobalState>(
   global: T,
   chatId: string,
-): string[] | undefined {
+) {
   return global.chats.similarChannelsById[chatId];
 }
 

src/global/types.ts

@@ -234,6 +234,7 @@ export type TabState = {
   };
 
   nextProfileTab?: ProfileTabType;
+  forceScrollProfileTab?: boolean;
   nextSettingsScreen?: SettingsScreens;
   nextFoldersAction?: ReducerAction<FoldersActions>;
   shareFolderScreen?: {
@@ -807,7 +808,14 @@ export type GlobalState = {
     forDiscussionIds?: string[];
     // Obtained from GetFullChat / GetFullChannel
     fullInfoById: Record<string, ApiChatFullInfo>;
-    similarChannelsById: Record<string, string[]>;
+    similarChannelsById: Record<
+    string,
+    {
+      shouldShowInChat: boolean;
+      similarChannelIds: string[];
+      count: number;
+    }
+    >;
   };
 
   messages: {
@@ -1223,7 +1231,10 @@ export interface ActionPayloads {
     onReplace?: VoidFunction;
     shouldReplace?: boolean;
   };
-  openChatWithInfo: ActionPayloads['openChat'] & { profileTab?: ProfileTabType } & WithTabId;
+  openChatWithInfo: ActionPayloads['openChat'] & {
+    profileTab?: ProfileTabType;
+    forceScrollProfileTab?: boolean;
+  } & WithTabId;
   openThreadWithInfo: ActionPayloads['openThread'] & WithTabId;
   openLinkedChat: { id: string } & WithTabId;
   loadMoreMembers: WithTabId | undefined;
@@ -1809,6 +1820,9 @@ export interface ActionPayloads {
   fetchChannelRecommendations: {
     chatId: string;
   };
+  toggleChannelRecommendations: {
+    chatId: string;
+  };
   updateChatMutedState: {
     chatId: string;
     isMuted?: boolean;