fix(app): separate unread state from unread counts

fluxer_app/src/features/app/components/layout/ChannelItem.tsx

@@ -230,6 +230,7 @@ export const ChannelItem = observer(
 		const isVoiceDragActive = draggingChannel?.channelType === ChannelTypes.GUILD_VOICE;
 		const shouldDimForVoiceDrag = Boolean(isVoiceDragActive && channelIsText && channel.parentId !== null);
 		const unreadCount = ReadStates.getUnreadCount(channel.id);
+		const hasUnread = ReadStates.hasUnread(channel.id);
 		const connectedVoiceGuildId = channelIsVoice ? MediaEngine.guildId : null;
 		const connectedVoiceChannelId = channelIsVoice ? MediaEngine.channelId : null;
 		const canManageChannels = Permission.can(Permissions.MANAGE_CHANNELS, channel);
@@ -265,6 +266,7 @@ export const ChannelItem = observer(
 			type: channel.type,
 		});
 		const unreadState = getChannelUnreadState({
+			hasUnread,
 			unreadCount,
 			mentionCount,
 			isMuted: isChannelDirectlyMuted,

fluxer_app/src/features/app/components/layout/ChannelListContent.tsx

@@ -335,6 +335,7 @@ export const ChannelListContent = observer(({guild, scrollY}: {guild: Guild; scr
 	);
 	const hasVisibleUnreadInChannel = (channelId: string): boolean => {
 		const unreadCount = ReadStates.getUnreadCount(channelId);
+		const hasUnread = ReadStates.hasUnread(channelId);
 		const mentionCount = ReadStates.getMentionCount(channelId);
 		const isMuted =
 			UserGuildSettings.isParentCategoryMuted(guild.id, channelId) ||
@@ -349,6 +350,7 @@ export const ChannelListContent = observer(({guild, scrollY}: {guild: Guild; scr
 				})
 			: null;
 		const unreadState = getChannelUnreadState({
+			hasUnread,
 			unreadCount,
 			mentionCount,
 			isMuted,

fluxer_app/src/features/app/components/layout/FavoritesChannelListContent.tsx

@@ -197,6 +197,7 @@ const FavoriteChannelResolvedItem = observer(
 		);
 		const refs = useMergeRefs([dragConnectorRef, dropConnectorRef, elementRef]);
 		const unreadCount = ReadStates.getUnreadCount(channel.id);
+		const hasUnread = ReadStates.hasUnread(channel.id);
 		const mentionCount = ReadStates.getMentionCount(channel.id);
 		const isGroupDM = channel.isGroupDM();
 		const isDM = channel.isDM();
@@ -220,6 +221,7 @@ const FavoriteChannelResolvedItem = observer(
 				})
 			: null;
 		const unreadState = getChannelUnreadState({
+			hasUnread,
 			unreadCount,
 			mentionCount,
 			isMuted,

fluxer_app/src/features/app/components/layout/GuildsLayout.tsx

@@ -663,6 +663,7 @@ function resolveGuildTargetBounds({
 function getDMScrollIndicatorSeverity(channelId: string): ScrollIndicatorSeverity | null {
 	const mentionCount = ReadStates.getPrivateChannelMentionCount(channelId);
 	const unreadState = getChannelUnreadState({
+		hasUnread: ReadStates.hasUnreadPrivateChannel(channelId),
 		unreadCount: ReadStates.getPrivateChannelUnreadCount(channelId),
 		mentionCount,
 		isMuted: UserGuildSettings.isChannelDirectlyMuted(null, channelId),

fluxer_app/src/features/app/components/layout/sidebar_nav/GuildListDMItem.tsx

@@ -70,6 +70,7 @@ const ACTIVE_CALL_DESCRIPTOR = msg({
 
 export function resolveDMListItemUnreadState(channelId: string): ChannelUnreadState {
 	return getChannelUnreadState({
+		hasUnread: ReadStates.hasUnread(channelId),
 		unreadCount: ReadStates.getUnreadCount(channelId),
 		mentionCount: ReadStates.getMentionCount(channelId),
 		isMuted: UserGuildSettings.isChannelDirectlyMuted(null, channelId),

fluxer_app/src/features/app/components/layout/utils/ChannelUnreadState.test.ts

@@ -7,6 +7,7 @@ import {getChannelUnreadState} from './ChannelUnreadState';
 describe('getChannelUnreadState', () => {
 	it('shows a normal unread indicator for all-messages unread badges', () => {
 		const state = getChannelUnreadState({
+			hasUnread: true,
 			unreadCount: 3,
 			mentionCount: 0,
 			isMuted: false,
@@ -19,6 +20,7 @@ describe('getChannelUnreadState', () => {
 	});
 	it('shows a muted unread indicator for only-mentions unread badges without highlighting the channel', () => {
 		const state = getChannelUnreadState({
+			hasUnread: true,
 			unreadCount: 3,
 			mentionCount: 0,
 			isMuted: false,
@@ -31,6 +33,7 @@ describe('getChannelUnreadState', () => {
 	});
 	it('hides unread and mention surfaces when unread badges are disabled', () => {
 		const state = getChannelUnreadState({
+			hasUnread: true,
 			unreadCount: 3,
 			mentionCount: 1,
 			isMuted: false,
@@ -43,6 +46,7 @@ describe('getChannelUnreadState', () => {
 	});
 	it('keeps legacy muted-channel fading for channels without an unread-badges level', () => {
 		const hiddenState = getChannelUnreadState({
+			hasUnread: true,
 			unreadCount: 3,
 			mentionCount: 0,
 			isMuted: true,
@@ -50,6 +54,7 @@ describe('getChannelUnreadState', () => {
 			unreadBadgesLevel: null,
 		});
 		const fadedState = getChannelUnreadState({
+			hasUnread: true,
 			unreadCount: 3,
 			mentionCount: 0,
 			isMuted: true,
@@ -60,4 +65,27 @@ describe('getChannelUnreadState', () => {
 		expect(fadedState.shouldShowUnreadIndicator).toBe(true);
 		expect(fadedState.isUnreadIndicatorMuted).toBe(true);
 	});
+	it('shows the indicator from the unread flag rather than the message count', () => {
+		const state = getChannelUnreadState({
+			hasUnread: true,
+			unreadCount: 0,
+			mentionCount: 0,
+			isMuted: false,
+			showFadedUnreadOnMutedChannels: false,
+			unreadBadgesLevel: null,
+		});
+		expect(state.shouldShowUnreadIndicator).toBe(true);
+	});
+	it('hides the indicator for a read channel even if a stale count survives', () => {
+		const state = getChannelUnreadState({
+			hasUnread: false,
+			unreadCount: 7,
+			mentionCount: 0,
+			isMuted: false,
+			showFadedUnreadOnMutedChannels: false,
+			unreadBadgesLevel: null,
+		});
+		expect(state.shouldShowUnreadIndicator).toBe(false);
+		expect(state.hasVisibleUnread).toBe(false);
+	});
 });

fluxer_app/src/features/app/components/layout/utils/ChannelUnreadState.ts

@@ -3,6 +3,7 @@
 import {resolveChannelUnreadState} from './ChannelUnreadStateMachine';
 
 export interface ChannelUnreadStateInput {
+	hasUnread: boolean;
 	unreadCount: number;
 	mentionCount: number;
 	isMuted: boolean;
@@ -20,6 +21,7 @@ export interface ChannelUnreadState {
 }
 
 export function getChannelUnreadState({
+	hasUnread,
 	unreadCount,
 	mentionCount,
 	isMuted,
@@ -27,6 +29,7 @@ export function getChannelUnreadState({
 	unreadBadgesLevel,
 }: ChannelUnreadStateInput): ChannelUnreadState {
 	return resolveChannelUnreadState({
+		hasUnread,
 		unreadCount,
 		mentionCount,
 		isMuted,

fluxer_app/src/features/app/components/layout/utils/ChannelUnreadStateMachine.test.ts

@@ -12,6 +12,7 @@ import {
 
 function input(overrides: Partial<ChannelUnreadStateInput> = {}): ChannelUnreadStateInput {
 	return {
+		hasUnread: false,
 		unreadCount: 0,
 		mentionCount: 0,
 		isMuted: false,
@@ -38,6 +39,7 @@ describe('channelUnreadStateMachine', () => {
 		const snapshot = createChannelUnreadSnapshot(
 			input({
 				unreadBadgesLevel: MessageNotifications.NO_MESSAGES,
+				hasUnread: true,
 				unreadCount: 1,
 				mentionCount: 1,
 			}),
@@ -55,6 +57,7 @@ describe('channelUnreadStateMachine', () => {
 	it('transitions without preserving stale policy output', () => {
 		const legacySnapshot = createChannelUnreadSnapshot(
 			input({
+				hasUnread: true,
 				unreadCount: 2,
 				isMuted: true,
 				showFadedUnreadOnMutedChannels: false,
@@ -66,6 +69,7 @@ describe('channelUnreadStateMachine', () => {
 			type: 'channelUnread.updated',
 			input: input({
 				unreadBadgesLevel: MessageNotifications.ALL_MESSAGES,
+				hasUnread: true,
 				unreadCount: 2,
 				isMuted: true,
 			}),

fluxer_app/src/features/app/components/layout/utils/ChannelUnreadStateMachine.ts

@@ -86,7 +86,7 @@ export function transitionChannelUnreadSnapshot(
 
 export function selectChannelUnreadState(snapshot: ChannelUnreadSnapshot): ChannelUnreadState {
 	const context = snapshot.context;
-	const hasUnreadMessages = context.unreadCount > 0;
+	const hasUnreadMessages = context.hasUnread;
 	const rawHasMentions = context.mentionCount > 0;
 	switch (getUnreadStateValue(snapshot)) {
 		case 'disabled':

fluxer_app/src/features/channel/components/direct_message/DMListItem.tsx

@@ -135,6 +135,7 @@ const ResolvedDMListItem = observer(function ResolvedDMListItem({
 	const isMuted = UserGuildSettings.isChannelDirectlyMuted(null, channel.id);
 	const mentionCount = ReadStates.getMentionCount(channel.id);
 	const unreadState = getChannelUnreadState({
+		hasUnread: ReadStates.hasUnread(channel.id),
 		unreadCount: ReadStates.getUnreadCount(channel.id),
 		mentionCount,
 		isMuted,

fluxer_app/src/features/read_state/state/ReadStates.test.ts

@@ -0,0 +1,114 @@
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+import {beforeEach, describe, expect, it, vi} from 'vitest';
+
+const makeChannel = (id: string) => ({
+	id,
+	type: 0,
+	guildId: 'guild-1',
+	isPrivate: () => false,
+	getGuildId: () => 'guild-1',
+});
+const loadedMessages: Array<{id: string; author: {id: string}}> = [];
+let hasMoreBefore = false;
+let hasNewestMessages = true;
+
+vi.mock('@app/features/channel/state/Channels', () => ({
+	default: {getChannel: (id: string) => makeChannel(id), getBasicChannel: (id: string) => makeChannel(id)},
+}));
+vi.mock('@app/features/messaging/state/MessagingMessages', () => ({
+	default: {
+		getMessages: () => ({
+			get hasMoreBefore() {
+				return hasMoreBefore;
+			},
+			get length() {
+				return loadedMessages.length;
+			},
+			jumpDestinationId: null,
+			hasNewestMessages: () => hasNewestMessages,
+			has: (id: string) => loadedMessages.some((m) => m.id === id),
+			last: () => loadedMessages[loadedMessages.length - 1],
+			forEachBuffered: (cb: (m: unknown) => void) => {
+				for (const m of loadedMessages) cb(m);
+			},
+		}),
+	},
+}));
+vi.mock('@app/features/user/state/Users', () => ({default: {getCurrentUser: () => ({id: 'me'})}}));
+vi.mock('@app/features/relationship/state/Relationships', () => ({default: {isBlocked: () => false}}));
+vi.mock('@app/features/member/state/GuildMembers', () => ({default: {getMember: () => null}}));
+vi.mock('@app/features/user/state/UserGuildSettings', () => ({
+	default: {
+		isEveryoneMentionSuppressed: () => false,
+		isRoleMentionSuppressed: () => false,
+		isGuildOrChannelMuted: () => false,
+	},
+}));
+vi.mock('@app/features/ui/state/Dimension', () => ({default: {channelPinnedToEnd: () => false}}));
+vi.mock('@app/features/notification/state/NotificationAutoAck', () => ({
+	default: {isAutomaticAckEnabled: () => false},
+}));
+vi.mock('@app/features/platform/transport/RestTransport', () => ({http: {post: vi.fn(), get: vi.fn()}}));
+
+const {default: ReadStates} = await import('@app/features/read_state/state/ReadStates');
+
+const ID = {
+	ack: '1519773906704011264',
+	newer: '1519773906708205568',
+};
+
+let nextChannelId = 0;
+
+function seedReadChannel() {
+	const channelId = `channel-${++nextChannelId}`;
+	const state = ReadStates.get(channelId);
+	state.readStateKnown = true;
+	state.ackMessageId = ID.ack;
+	state.lastMessageId = ID.ack;
+	state.unreadCount = 0;
+	state.oldestUnreadMessageId = null;
+	return {channelId, state};
+}
+
+describe('ReadStates unread invariant', () => {
+	beforeEach(() => {
+		loadedMessages.length = 0;
+		hasMoreBefore = false;
+		hasNewestMessages = true;
+	});
+
+	it('never reports a positive unread count without an unread anchor after a passive update', () => {
+		const {channelId} = seedReadChannel();
+		ReadStates.handlePassiveLastMessageUpdates({[channelId]: ID.newer}, 'guild-1');
+		const count = ReadStates.getUnreadCount(channelId);
+		const anchor = ReadStates.getVisualUnreadMessageId(channelId);
+		expect(count > 0).toBe(anchor != null);
+	});
+
+	it('keeps the channel unread for the sidebar even with no anchor to draw a divider at', () => {
+		const {channelId} = seedReadChannel();
+		ReadStates.handlePassiveLastMessageUpdates({[channelId]: ID.newer}, 'guild-1');
+		expect(ReadStates.hasUnread(channelId)).toBe(true);
+	});
+
+	it('clears a stale unread once the server walks the last message id back', () => {
+		const {channelId} = seedReadChannel();
+		ReadStates.handlePassiveLastMessageUpdates({[channelId]: ID.newer}, 'guild-1');
+		expect(ReadStates.hasUnread(channelId)).toBe(true);
+		ReadStates.handlePassiveLastMessageUpdates({[channelId]: ID.ack}, 'guild-1');
+		expect(ReadStates.hasUnread(channelId)).toBe(false);
+		expect(ReadStates.getUnreadCount(channelId)).toBe(0);
+		expect(ReadStates.getVisualUnreadMessageId(channelId)).toBeNull();
+	});
+
+	it('anchors the divider when a window is loaded whose ack sits outside it', () => {
+		const {channelId, state} = seedReadChannel();
+		state.lastMessageId = ID.newer;
+		hasMoreBefore = true;
+		loadedMessages.push({id: ID.newer, author: {id: 'someone'}});
+		ReadStates.handleLoadMessages({channelId, messages: []});
+		expect(ReadStates.getVisualUnreadMessageId(channelId)).toBe(ID.newer);
+		expect(ReadStates.getUnreadCount(channelId) > 0).toBe(true);
+	});
+});

fluxer_app/src/features/read_state/state/ReadStates.ts

@@ -141,16 +141,11 @@ class ReadStates {
 		this.refreshMentionChannel(state.channelId);
 	}
 
-	private refreshUnreadEstimate(state: ReadStateEntry): void {
+	private clearUnreadStateIfRead(state: ReadStateEntry): void {
 		if (!state.hasUnread()) {
 			state.estimated = false;
 			state.unreadCount = 0;
 			state.oldestUnreadMessageId = null;
-			return;
-		}
-		if (state.unreadCount === 0) {
-			state.estimated = true;
-			state.unreadCount = Math.max(1, state.mentionCount);
 		}
 	}
 
@@ -416,7 +411,7 @@ class ReadStates {
 				if (!channelsWithReadState.has(channel.id as ChannelId)) {
 					this.setMentionCount(state, 0);
 				}
-				this.refreshUnreadEstimate(state);
+				this.clearUnreadStateIfRead(state);
 			}
 			this.notifyChange(undefined, {global: true});
 		});
@@ -436,7 +431,7 @@ class ReadStates {
 					state.lastMessageId = channel.last_message_id ?? null;
 					state.lastPinTimestamp = parseTimestamp(channel.last_pin_timestamp);
 					state.storedGuildId = action.guild.id;
-					this.refreshUnreadEstimate(state);
+					this.clearUnreadStateIfRead(state);
 					this.refreshMentionChannel(channel.id);
 				}
 			}
@@ -452,9 +447,11 @@ class ReadStates {
 		if (newestMessage != null && isNewerMessageId(newestMessage.id, state.lastMessageId)) {
 			state.lastMessageId = newestMessage.id;
 		}
-		if (state.hasUnread()) {
+		const landedOnNewestWindow = messages.hasNewestMessages();
+		const landedOnAck = state.ackMessageId != null && messages.jumpDestinationId === state.ackMessageId;
+		if (state.hasUnread() || landedOnNewestWindow || landedOnAck) {
 			state.rebuild();
-			this.refreshUnreadEstimate(state);
+			this.clearUnreadStateIfRead(state);
 		} else if (action.isAfter && state.ackMessageId != null && messages.has(state.ackMessageId, true)) {
 			state.unreadCount += action.messages.length;
 			if (state.oldestUnreadMessageId == null) {
@@ -564,7 +561,7 @@ class ReadStates {
 			state.readStateKnown = true;
 			state.ackMessageId = action.channel.last_message_id;
 		} else if (GUILD_TEXT_BASED_CHANNEL_TYPES.has(action.channel.type) && state.hasUnread()) {
-			this.refreshUnreadEstimate(state);
+			this.clearUnreadStateIfRead(state);
 		}
 		this.notifyChange(action.channel.id);
 	}
@@ -586,10 +583,10 @@ class ReadStates {
 				changed = state.guildId !== guildId;
 				state.storedGuildId = guildId;
 			}
-			if (isNewerMessageId(lastMessageId, state.lastMessageId)) {
+			if (lastMessageId !== state.lastMessageId) {
 				state.lastMessageId = lastMessageId;
 				changed = true;
-				this.refreshUnreadEstimate(state);
+				this.clearUnreadStateIfRead(state);
 			}
 			if (changed) {
 				changedChannels.push(channelId as ChannelId);
@@ -751,7 +748,7 @@ class ReadStates {
 					this.setMentionCount(state, mentionCount);
 				}
 				if (decision.shouldRefreshUnreadEstimate) {
-					this.refreshUnreadEstimate(state);
+					this.clearUnreadStateIfRead(state);
 				}
 				if (decision.shouldNotify) {
 					this.notifyChange(action.channelId);
@@ -1046,7 +1043,7 @@ class ReadStates {
 				state.serverVersion = readState.version ?? state.serverVersion;
 				this.setMentionCount(state, readState.mention_count ?? 0);
 				state.rebuild(null, {recomputeMentions: manual});
-				this.refreshUnreadEstimate(state);
+				this.clearUnreadStateIfRead(state);
 				this.notifyChange(readState.id);
 				continue;
 			}

fluxer_app/src/features/read_state/state/read_states/ReadStateEntry.ts

@@ -274,7 +274,7 @@ export class ReadStateEntry {
 		});
 		const hasUnreadBoundary = foundAckMessage || loadedOlderMessages || !messages.hasMoreBefore;
 		const hasNewestMessages = messages.hasNewestMessages();
-		this.estimated = !hasNewestMessages || !hasUnreadBoundary;
+		this.estimated = !hasNewestMessages || (!hasUnreadBoundary && messages.length === loadedUnreadCount);
 		if (this.estimated) {
 			this.unreadCount = Math.max(previousUnreadCount, loadedUnreadCount);
 		} else {

fluxer_app/src/features/search/state/QuickSwitcherCandidateBuilder.ts

@@ -61,10 +61,7 @@ function getChannelRecency(channel: {id: string; lastMessageId: string | null}):
 }
 
 function getChannelSortWeight(channelId: string, baseWeight: number): number {
-	const unreadCount = ReadStates.getUnreadCount(channelId);
-	const mentionCount = ReadStates.getMentionCount(channelId);
-	const hasUnread = unreadCount > 0 || mentionCount > 0;
-	return hasUnread ? baseWeight + UNREAD_SORT_WEIGHT_BOOST : baseWeight;
+	return ReadStates.isUnreadOrMentioned(channelId) ? baseWeight + UNREAD_SORT_WEIGHT_BOOST : baseWeight;
 }
 
 export function buildChannelCandidate(

fluxer_app/src/features/ui/action_menu/items/GuildMenuData.tsx

@@ -182,7 +182,7 @@ export function useGuildMenuData(guild: Guild, options: UseGuildMenuDataOptions)
 		() => ({
 			handleMarkAsRead: () => {
 				const channelIds = channels
-					.filter((channel) => ReadStates.getUnreadCount(channel.id) > 0)
+					.filter((channel) => ReadStates.isUnreadOrMentioned(channel.id))
 					.map((channel) => channel.id);
 				if (channelIds.length > 0) {
 					void ReadStateCommands.bulkAckChannels(channelIds);

fluxer_app/src/features/ui/action_menu/items/GuildMenuItems.tsx

@@ -100,7 +100,7 @@ export const MarkAsReadMenuItem: React.FC<GuildMenuItemProps> = observer(({guild
 	}, [channels]);
 	const handleMarkAsRead = useCallback(() => {
 		const channelIds = channels
-			.filter((channel) => ReadStates.getUnreadCount(channel.id) > 0)
+			.filter((channel) => ReadStates.isUnreadOrMentioned(channel.id))
 			.map((channel) => channel.id);
 		if (channelIds.length > 0) {
 			void ReadStateCommands.bulkAckChannels(channelIds);