feat(forums): hide posts from blocked users

app/Community/Actions/BuildAggregateRecentForumPostsDataAction.php

@@ -8,6 +8,7 @@
 use App\Data\PaginatedData;
 use App\Enums\Permissions;
 use App\Models\ForumTopic;
+use App\Models\ForumTopicComment;
 use App\Support\Shortcode\Shortcode;
 use Illuminate\Pagination\LengthAwarePaginator;
 use Illuminate\Support\Facades\DB;
@@ -18,14 +19,35 @@
  */
 class BuildAggregateRecentForumPostsDataAction
 {
+    /** Maximum comments to inspect for the masked recent-topics paginator. */
+    private const int MASKED_SCAN_WINDOW = 20000;
+
+    /**
+     * @param array<int, int> $maskedAuthorIds authors the viewer has blocked
+     */
     public function execute(
         int $permissions = Permissions::Unregistered,
         ?int $page = null,
         int $limit = 25,
         ?string $paginationPath = null,
         array $paginationQuery = [],
+        array $maskedAuthorIds = [],
     ): PaginatedData|array {
-        $topics = $this->getRecentForumTopics($page, $permissions, $limit);
+        $currentPage = $page ?? 1;
+
+        if (empty($maskedAuthorIds)) {
+            $topics = $this->getRecentForumTopics($currentPage, $permissions, $limit);
+            $total = $this->getTotalRecentForumTopics($permissions);
+        } else {
+            $maskedTopics = $this->getMaskedRecentForumTopics(
+                $currentPage,
+                $permissions,
+                $limit,
+                $maskedAuthorIds,
+            );
+            $topics = $maskedTopics['topics'];
+            $total = $maskedTopics['total'];
+        }
 
         $shortcodeIds = [];
         foreach ($topics as $topic) {
@@ -49,9 +71,9 @@ public function execute(
         // Create a paginated response.
         $paginator = new LengthAwarePaginator(
             items: $transformedTopics,
-            total: $this->getTotalRecentForumTopics($permissions),
+            total: $total,
             perPage: $limit,
-            currentPage: $page,
+            currentPage: $currentPage,
             options: [
                 'path' => $paginationPath,
                 'query' => $paginationQuery,
@@ -63,22 +85,116 @@ public function execute(
 
     private function getTotalRecentForumTopics(int $permissions = Permissions::Unregistered): int
     {
-        return ForumTopic::where("required_permissions", "<=", $permissions)
-            ->whereNull("deleted_at")
+        return ForumTopic::where('required_permissions', '<=', $permissions)
+            ->whereNull('deleted_at')
             ->where(function ($query) {
                 $query
-                    ->whereNotNull("latest_comment_id")
-                    ->orWhereIn("id", function ($subQuery) {
+                    ->whereNotNull('latest_comment_id')
+                    ->orWhereIn('id', function ($subQuery) {
                         $subQuery
-                            ->select("forum_topic_id")
+                            ->select('forum_topic_id')
                             ->distinct()
-                            ->from("forum_topic_comments")
-                            ->where("is_authorized", 1);
+                            ->from('forum_topic_comments')
+                            ->where('is_authorized', 1);
                     });
             })
             ->count();
     }
 
+    /**
+     * @param array<int, int> $maskedAuthorIds
+     * @return array{topics: array<int, array<string, mixed>>, total: int}
+     */
+    private function getMaskedRecentForumTopics(
+        int $page,
+        int $permissions,
+        int $count,
+        array $maskedAuthorIds,
+    ): array {
+        $offset = ($page - 1) * $count;
+
+        $recentVisibleComments = ForumTopicComment::query()
+            ->select(['forum_topic_comments.id', 'forum_topic_comments.forum_topic_id'])
+            ->join('forum_topics', 'forum_topics.id', '=', 'forum_topic_comments.forum_topic_id')
+            ->where('forum_topic_comments.is_authorized', 1)
+            ->whereNotIn('forum_topic_comments.author_id', $maskedAuthorIds)
+            ->whereNotIn('forum_topics.author_id', $maskedAuthorIds)
+            ->where('forum_topics.required_permissions', '<=', $permissions)
+            ->whereNull('forum_topics.deleted_at')
+            ->orderByDesc('forum_topic_comments.created_at')
+            ->orderByDesc('forum_topic_comments.id')
+            ->limit(self::MASKED_SCAN_WINDOW)
+            ->toBase()
+            ->get();
+
+        $latestVisibleCommentIdByTopic = [];
+        foreach ($recentVisibleComments as $comment) {
+            $latestVisibleCommentIdByTopic[(int) $comment->forum_topic_id] ??= (int) $comment->id;
+        }
+
+        $pagedCommentIds = array_slice(array_values($latestVisibleCommentIdByTopic), $offset, $count);
+
+        return [
+            'topics' => empty($pagedCommentIds) ? [] : $this->hydrateTopicsFromComments($pagedCommentIds),
+            'total' => count($latestVisibleCommentIdByTopic),
+        ];
+    }
+
+    /**
+     * @param array<int, int> $commentIds
+     */
+    private function hydrateTopicsFromComments(array $commentIds): array
+    {
+        $oneDayAgo = now()->subDay()->toDateTimeString();
+        $sevenDaysAgo = now()->subDays(7)->toDateTimeString();
+
+        $countsOneDay = ForumTopicComment::query()
+            ->selectRaw('forum_topic_id, MIN(id) AS CommentID, COUNT(*) AS Count')
+            ->where('is_authorized', 1)
+            ->where('created_at', '>=', $oneDayAgo)
+            ->groupBy('forum_topic_id');
+
+        $countsSevenDays = ForumTopicComment::query()
+            ->selectRaw('forum_topic_id, MIN(id) AS CommentID, COUNT(*) AS Count')
+            ->where('is_authorized', 1)
+            ->where('created_at', '>=', $sevenDaysAgo)
+            ->groupBy('forum_topic_id');
+
+        $results = ForumTopicComment::query()
+            ->select([
+                'forum_topics.id as ForumTopicID',
+                'forum_topics.title as ForumTopicTitle',
+                'f.id as ForumID',
+                'f.title as ForumTitle',
+                'forum_topic_comments.id as CommentID',
+                'forum_topic_comments.created_at as PostedAt',
+                'forum_topic_comments.author_id',
+                'ua.username as Author',
+                'ua.display_name as AuthorDisplayName',
+                'ua.avatar_updated_at',
+                'forum_topic_comments.body as ShortMsg',
+                'd1.CommentID as CommentID_1d',
+                'd1.Count as Count_1d',
+                'd7.CommentID as CommentID_7d',
+                'd7.Count as Count_7d',
+            ])
+            ->selectRaw('0 AS IsTruncated')
+            ->join('forum_topics', 'forum_topics.id', '=', 'forum_topic_comments.forum_topic_id')
+            ->join('forums as f', 'f.id', '=', 'forum_topics.forum_id')
+            ->leftJoin('users as ua', 'ua.id', '=', 'forum_topic_comments.author_id')
+            ->leftJoinSub($countsOneDay, 'd1', 'd1.forum_topic_id', '=', 'forum_topics.id')
+            ->leftJoinSub($countsSevenDays, 'd7', 'd7.forum_topic_id', '=', 'forum_topics.id')
+            ->whereIn('forum_topic_comments.id', $commentIds)
+            ->get()
+            ->map(fn (ForumTopicComment $comment): array => $comment->getAttributes())
+            ->keyBy(fn (array $topic): int => (int) $topic['CommentID']);
+
+        return array_values(array_filter(array_map(
+            fn (int $commentId): ?array => $results->get($commentId),
+            $commentIds,
+        )));
+    }
+
     private function getRecentForumTopics(int $page = 1, int $permissions = Permissions::Unregistered, int $count = 25): array
     {
         $offset = ($page - 1) * $count;

app/Community/Actions/BuildShowForumTopicPagePropsAction.php

@@ -45,8 +45,20 @@ public function execute(
             return ['props' => null, 'redirectToPage' => $lastPage];
         }
 
+        $maskedAuthorIds = (new GetMaskedForumAuthorIdsAction())->execute($user);
+        $canRevealMaskedPosts = $user && (new ForumTopicCommentPolicy())->manage($user);
+        $comments = $paginatedForumTopicComments->getCollection()->values();
+
         // Extract the post bodies for processing before they're sent to the UI.
-        $postBodies = $paginatedForumTopicComments->getCollection()->pluck('body')->all();
+        $postBodies = $comments->pluck('body')->all();
+
+        if (!$canRevealMaskedPosts) {
+            foreach ($comments as $index => $comment) {
+                if (in_array($comment->author_id, $maskedAuthorIds, true)) {
+                    $postBodies[$index] = '';
+                }
+            }
+        }
 
         // Convert user ID shortcodes to use display names.
         $updatedBodies = (new ConvertUserShortcodesFromIdsToDisplayNamesAction())->execute($postBodies);
@@ -83,8 +95,8 @@ public function execute(
         }
 
         // Finally, update the message bodies sent to the UI with the converted user shortcodes.
-        $forumTopicComments = $paginatedForumTopicComments->getCollection()->map(
-            function ($comment, $index) use ($updatedBodies, $user, $accessibleTeamIds) {
+        $forumTopicComments = $comments->map(
+            function ($comment, $index) use ($updatedBodies, $user, $accessibleTeamIds, $maskedAuthorIds, $canRevealMaskedPosts) {
                 $comment->body = $updatedBodies[$index];
 
                 $includes = [
@@ -103,21 +115,34 @@ function ($comment, $index) use ($updatedBodies, $user, $accessibleTeamIds) {
                  */
                 $shouldIncludeSentByEditedBy = $user && (
                     ($comment->sent_by_id !== null && in_array($comment->author_id, $accessibleTeamIds, true))
-                    || ($comment->edited_by_id !== null && (new ForumTopicCommentPolicy())->manage($user))
+                    || ($comment->edited_by_id !== null && $canRevealMaskedPosts)
                 );
 
                 if ($shouldIncludeSentByEditedBy) {
                     $includes[] = 'sentBy';
                     $includes[] = 'editedBy';
                 }
 
-                return ForumTopicCommentData::from($comment)->include(...$includes);
+                $data = ForumTopicCommentData::from($comment);
+                $data->isFromBlockedUser = in_array($comment->author_id, $maskedAuthorIds, true);
+
+                return $data->include(...$includes);
             }
         )->all();
 
-        $comments = collect($forumTopicComments);
-        /** @var ForumTopicComment $selectedComment */
-        $selectedComment = $comments->firstWhere('id', $selectedCommentId) ?? $comments->first();
+        $commentData = collect($forumTopicComments);
+        /** @var ForumTopicCommentData|null $selectedComment */
+        $selectedComment = $commentData->firstWhere('id', $selectedCommentId) ?? $commentData->first();
+
+        if ($selectedComment->isFromBlockedUser && !$canRevealMaskedPosts) {
+            $selectedComment = $commentData->last(
+                fn (ForumTopicCommentData $comment): bool => !$comment->isFromBlockedUser,
+            );
+        }
+
+        $metaDescription = $selectedComment
+            ? Shortcode::stripAndClamp($selectedComment->body, 220)
+            : $topic->title;
 
         $props = new ShowForumTopicPagePropsData(
             accessibleTeamAccounts: $accessibleTeamAccounts,
@@ -145,7 +170,7 @@ function ($comment, $index) use ($updatedBodies, $user, $accessibleTeamIds) {
                 total: $paginatedForumTopicComments->total(),
                 items: $forumTopicComments
             ),
-            metaDescription: Shortcode::stripAndClamp($selectedComment->body, 220),
+            metaDescription: $metaDescription,
         );
 
         return ['props' => $props, 'redirectToPage' => null];

app/Community/Actions/BuildThinRecentForumPostsDataAction.php

@@ -12,22 +12,28 @@
 
 class BuildThinRecentForumPostsDataAction
 {
+    /** Extra comments to read when masked authors can remove rows after the topic join. */
+    public const int MASKED_AUTHOR_SCAN_BUFFER = 250;
+
     /**
+     * @param array<int, int> $maskedAuthorIds authors the viewer has blocked
      * @return Collection<int, ForumTopicData>
      */
     public function execute(
         int $limit = 4,
         int $numMessageChars = 260,
         ?int $permissions = Permissions::Unregistered,
         ?int $fromAuthorId = null,
+        array $maskedAuthorIds = [],
     ): Collection {
         $userClause = $this->buildUserClause($fromAuthorId, $permissions);
 
         $subQuery = DB::table('forum_topic_comments as ftc')
             ->select('*')
             ->whereRaw($userClause)
+            ->whereNotIn('ftc.author_id', $maskedAuthorIds)
             ->orderBy('ftc.created_at', 'desc')
-            ->limit($limit + 20); // cater for spam messages
+            ->limit($limit + 20 + (empty($maskedAuthorIds) ? 0 : self::MASKED_AUTHOR_SCAN_BUFFER)); // cater for spam messages
 
         $latestComments = DB::table(DB::raw("({$subQuery->toSql()}) as LatestComments"))
             ->mergeBindings($subQuery)
@@ -47,6 +53,7 @@ public function execute(
             ])
             ->where('ft.required_permissions', '<=', $permissions ?? Permissions::Unregistered)
             ->whereNull('ft.deleted_at')
+            ->whereNotIn('ft.author_id', $maskedAuthorIds)
             ->orderBy('LatestComments.created_at', 'desc')
             ->limit($limit)
             ->get();

app/Community/Actions/GetMaskedForumAuthorIdsAction.php

@@ -0,0 +1,50 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Community\Actions;
+
+use App\Models\User;
+use App\Support\Cache\CacheKey;
+use Illuminate\Support\Facades\Cache;
+
+/**
+ * Finds the author IDs whose forum posts a viewer does not want to see.
+ * Moderators get no exemption. This action also removes team accounts
+ * from the set of users.
+ */
+class GetMaskedForumAuthorIdsAction
+{
+    /**
+     * @return array<int, int>
+     */
+    public function execute(?User $viewer): array
+    {
+        if (!$viewer) {
+            return [];
+        }
+
+        return Cache::remember(
+            CacheKey::buildUserMaskedForumAuthorIdsCacheKey($viewer->id),
+            now()->addMinutes(5),
+            function () use ($viewer): array {
+                $blockedIds = $viewer->blockedUsers()->pluck('users.id')->all();
+
+                if (empty($blockedIds)) {
+                    return [];
+                }
+
+                // Official team communication stays visible no matter who a
+                // viewer has blocked. Team accounts speak for the website itself.
+                $teamAccountIds = User::whereIn('username', array_keys(config('teams.accounts', [])))
+                    ->pluck('id')
+                    ->all();
+
+                return array_values(array_map(
+                    'intval',
+                    array_diff($blockedIds, $teamAccountIds),
+                ));
+            },
+        );
+    }
+}

app/Community/Components/ForumRecentActivity.php

@@ -4,6 +4,7 @@
 
 namespace App\Community\Components;
 
+use App\Community\Actions\GetMaskedForumAuthorIdsAction;
 use App\Enums\Permissions;
 use App\Enums\UserPreference;
 use App\Models\User;
@@ -41,7 +42,8 @@ public function render(): ?View
     private function prepareRecentForumPosts(int $numToFetch = 4, int $userPermissions = Permissions::Unregistered, int $userPreferences = 0): array
     {
         $recentForumPosts = [];
-        $rawRecentPosts = getRecentForumPosts(0, $numToFetch, 100, $userPermissions);
+        $maskedAuthorIds = (new GetMaskedForumAuthorIdsAction())->execute($this->user);
+        $rawRecentPosts = getRecentForumPosts(0, $numToFetch, 100, $userPermissions, maskedAuthorIds: $maskedAuthorIds);
 
         if ($rawRecentPosts->isEmpty()) {
             return $recentForumPosts;

app/Community/Concerns/ActsAsCommunityMember.php

@@ -135,6 +135,14 @@ public function followerUsers(): BelongsToMany
         return $this->inverseRelatedUsers()->where('status', '=', UserRelationStatus::Following);
     }
 
+    /**
+     * @return BelongsToMany<User, $this>
+     */
+    public function blockedUsers(): BelongsToMany
+    {
+        return $this->relatedUsers()->where('status', '=', UserRelationStatus::Blocked);
+    }
+
     /**
      * Rows for users this user follows.
      *