chore(demo): add channel preview overlay

examples/vite/src/App.tsx

@@ -291,11 +291,18 @@ const App = () => {
         { type: 'public' },
         // public example channels
         {
-          cid: {
-            $in: ['random', 'general', 'music', 'jokes'].map(
-              (channelId) => `messaging:${channelId}`,
-            ),
-          },
+          $and: [
+            {
+              cid: {
+                $in: ['random', 'general', 'music', 'jokes'].map(
+                  (channelId) => `messaging:${channelId}`,
+                ),
+              },
+            },
+            {
+              members: { $in: [userId] },
+            },
+          ],
         },
       ],
     }),

examples/vite/src/ChatLayout/Panels.tsx

@@ -1,11 +1,6 @@
 import clsx from 'clsx';
-import type {
-  ChannelFilters,
-  ChannelMemberResponse,
-  ChannelOptions,
-  ChannelSort,
-} from 'stream-chat';
-import { useCallback, useEffect, useRef } from 'react';
+import type { ChannelFilters, ChannelOptions, ChannelSort } from 'stream-chat';
+import { useEffect, useRef } from 'react';
 import {
   AIStateIndicator,
   Channel,
@@ -26,14 +21,13 @@ import {
   useChatContext,
   type ChatViewSelectorEntry,
   useThreadsViewContext,
-  Button,
-  useChannelMembersState,
 } from 'stream-chat-react';
 
 import { useAppSettingsSelector } from '../AppSettings/state';
 import { DESKTOP_LAYOUT_BREAKPOINT } from './constants.ts';
 import { SidebarResizeHandle, ThreadResizeHandle } from './Resize.tsx';
 import { ReturnToSkipNavigation } from '../AccessibilityNavigation/ReturnToSkipNavigation.tsx';
+import { PublicChannelOverlay } from '../PublicChannelOverlay/PublicChannelOverlay.tsx';
 import { useSidebar } from './SidebarContext.tsx';
 import { ThreadStateSync } from './Sync.tsx';
 
@@ -82,56 +76,31 @@ const ResponsiveChannelPanels = () => {
       <WithDragAndDropUpload className='app-chat-view__channel-main'>
         <Window>
           <ChannelHeader Avatar={ChannelAvatar} />
-          {messageListType === 'virtualized' ? (
-            <VirtualizedMessageList returnAllReadData shouldGroupByUser />
-          ) : (
-            <MessageList returnAllReadData />
-          )}
-          <ReturnToSkipNavigation />
-          <AIStateIndicator />
-          <MessageComposer
-            additionalTextareaProps={{
-              id: CHANNEL_MESSAGE_COMPOSER_TEXTAREA_TARGET_ID,
-            }}
-            audioRecordingEnabled
-            maxRows={10}
-            asyncMessagesMultiSendEnabled
-          />
+          <div className='app-chat-view__channel-body'>
+            {messageListType === 'virtualized' ? (
+              <VirtualizedMessageList returnAllReadData shouldGroupByUser />
+            ) : (
+              <MessageList returnAllReadData />
+            )}
+            <ReturnToSkipNavigation />
+            <AIStateIndicator />
+            <MessageComposer
+              additionalTextareaProps={{
+                id: CHANNEL_MESSAGE_COMPOSER_TEXTAREA_TARGET_ID,
+              }}
+              audioRecordingEnabled
+              maxRows={10}
+              asyncMessagesMultiSendEnabled
+            />
+            <PublicChannelOverlay />
+          </div>
         </Window>
       </WithDragAndDropUpload>
       <ChannelThreadPanel />
     </div>
   );
 };
 
-const HeaderStartContent = () => {
-  const { client } = useChatContext();
-  const { channel } = useChannelStateContext();
-  const members = useChannelMembersState(channel);
-  const membership = members[client.userID!] as ChannelMemberResponse | undefined;
-
-  const isMember = typeof membership?.channel_role === 'string';
-  const canJoin = channel.data?.own_capabilities?.includes('join-channel');
-
-  const handleClick = useCallback(() => {
-    if (isMember) {
-      channel.removeMembers([client.userID!]).then(() => {
-        channel.watch();
-      });
-    } else {
-      channel.addMembers([client.userID!]);
-    }
-  }, [isMember]);
-
-  if (!canJoin) return null;
-
-  return (
-    <Button onClick={handleClick} variant='secondary' appearance='outline' size='sm'>
-      {isMember ? 'Leave' : 'Join'}
-    </Button>
-  );
-};
-
 export const ChannelsPanels = ({
   filters,
   iconOnly,
@@ -193,7 +162,7 @@ export const ChannelsPanels = ({
           </WithComponents>
         </div>
         <SidebarResizeHandle layoutRef={channelsLayoutRef} />
-        <WithComponents overrides={{ TypingIndicator, HeaderStartContent }}>
+        <WithComponents overrides={{ TypingIndicator }}>
           <Channel>
             <ResponsiveChannelPanels />
           </Channel>

examples/vite/src/PublicChannelOverlay/PublicChannelOverlay.scss

@@ -0,0 +1,87 @@
+.app-public-channel-overlay {
+  position: absolute;
+  inset: 0;
+  z-index: 1;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  backdrop-filter: blur(5px);
+  background: rgba(255, 255, 255, 0.75);
+  padding: 12px 0;
+
+  .str-chat__theme-dark & {
+    background: rgba(0, 0, 0, 0.75);
+  }
+}
+
+.app-public-channel-overlay__content {
+  position: relative;
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  padding: 40px 48px;
+  overscroll-behavior: contain;
+
+  &::before {
+    content: '';
+    position: absolute;
+    inset: -120px;
+    border-radius: 50%;
+    background: radial-gradient(
+      circle,
+      rgba(255, 255, 255, 0.9) 0%,
+      rgba(255, 255, 255, 0.85) 40%,
+      rgba(255, 255, 255, 0) 70%
+    );
+    filter: blur(20px);
+    z-index: -1;
+
+    .str-chat__theme-dark & {
+      background: radial-gradient(
+        circle,
+        rgba(0, 0, 0, 0.6) 0%,
+        rgba(0, 0, 0, 0.55) 40%,
+        rgba(0, 0, 0, 0) 70%
+      );
+    }
+  }
+
+  .str-chat__icon {
+    width: 32px;
+    height: 32px;
+    color: var(--str-chat__text-tertiary);
+  }
+}
+
+.app-public-channel-overlay__text {
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  text-align: center;
+  gap: var(--str-chat__spacing-xxs);
+  margin-block: var(--str-chat__spacing-sm) var(--str-chat__spacing-xl);
+
+  p {
+    margin: 0;
+  }
+}
+
+.app-public-channel-overlay__title {
+  font: var(--str-chat__font-heading-xs);
+  color: var(--str-chat__text-color);
+}
+
+.app-public-channel-overlay__description {
+  font: var(--str-chat__font-caption-default);
+  color: var(--str-chat__text-secondary);
+  max-width: 200px;
+}
+
+.app-public-channel-overlay__join-button {
+  width: 106px;
+
+  .str-chat__loading-indicator {
+    height: 20px;
+    width: 20px;
+  }
+}

examples/vite/src/PublicChannelOverlay/PublicChannelOverlay.tsx

@@ -0,0 +1,74 @@
+import { useCallback, useState } from 'react';
+import type { ChannelMemberResponse } from 'stream-chat';
+import {
+  Button,
+  IconMessageBubbles,
+  LoadingIndicator,
+  useChannelMembersState,
+  useChannelStateContext,
+  useChatContext,
+  useNotificationApi,
+} from 'stream-chat-react';
+
+import './PublicChannelOverlay.scss';
+
+export const PublicChannelOverlay = () => {
+  const { client } = useChatContext();
+  const { channel } = useChannelStateContext();
+  const members = useChannelMembersState(channel);
+  const membership = members[client.userID!] as ChannelMemberResponse | undefined;
+  const { addNotification } = useNotificationApi();
+  const [joining, setJoining] = useState(false);
+
+  const isMember = typeof membership?.channel_role === 'string';
+  const canJoin = channel.data?.own_capabilities?.includes('join-channel');
+
+  const handleJoin = useCallback(async () => {
+    setJoining(true);
+    try {
+      await channel.addMembers([client.userID!]);
+    } catch (error) {
+      addNotification({
+        emitter: 'PublicChannelOverlay',
+        incident: {
+          domain: 'api',
+          entity: 'channel',
+          operation: 'join',
+        },
+        message: 'Failed to join the group',
+        severity: 'error',
+        error: error instanceof Error ? error : new Error(String(error)),
+      });
+    } finally {
+      setJoining(false);
+    }
+  }, [addNotification, channel, client.userID]);
+
+  if (isMember || !canJoin) return null;
+
+  return (
+    <div className='app-public-channel-overlay'>
+      <div className='app-public-channel-overlay__content'>
+        <IconMessageBubbles />
+        <div className='app-public-channel-overlay__text'>
+          <p className='app-public-channel-overlay__title'>
+            You're previewing this group
+          </p>
+          <p className='app-public-channel-overlay__description'>
+            Join to send messages and follow the conversation
+          </p>
+        </div>
+        <Button
+          appearance='solid'
+          className='app-public-channel-overlay__join-button'
+          disabled={joining}
+          onClick={handleJoin}
+          size='md'
+          variant='primary'
+        >
+          {joining ? <LoadingIndicator /> : 'Join Group'}
+        </Button>
+      </div>
+    </div>
+  );
+};

examples/vite/src/index.scss

@@ -138,6 +138,14 @@ body {
     height: 100%;
   }
 
+  .app-chat-view__channel-body {
+    position: relative;
+    display: flex;
+    flex-direction: column;
+    flex: 1 1 auto;
+    min-height: 0;
+  }
+
   .app-chat-view__threads-main > * {
     flex: 1 1 auto;
     min-width: 0;