From 22ad776635efd75b76886a007d97ee7e20118886 Mon Sep 17 00:00:00 2001
From: KMY <tt@kmycode.net>
Date: Thu, 6 Jul 2023 12:55:11 +0900
Subject: [PATCH] Add status references support

---
 .rubocop.yml                                  |  1 +
 .../mastodon/actions/notifications.js         |  1 +
 .../components/column_settings.jsx            | 11 +++
 .../notifications/components/filter_bar.jsx   |  8 ++
 .../notifications/components/notification.jsx | 36 ++++++++
 app/javascript/mastodon/locales/ja.json       |  1 +
 app/lib/activitypub/activity/create.rb        |  7 ++
 app/models/notification.rb                    | 10 ++-
 app/models/status.rb                          | 12 +++
 app/models/status_reference.rb                | 25 ++++++
 app/models/status_stat.rb                     |  5 ++
 app/models/user.rb                            |  1 +
 app/serializers/rest/instance_serializer.rb   |  1 +
 .../rest/notification_serializer.rb           |  2 +-
 app/serializers/rest/status_serializer.rb     |  9 ++
 .../rest/v1/instance_serializer.rb            |  1 +
 .../activitypub/fetch_references_service.rb   | 49 +++++++++++
 app/services/post_status_service.rb           |  4 +
 app/services/process_references_service.rb    | 86 +++++++++++++++++++
 app/services/update_status_service.rb         |  1 +
 app/workers/process_references_worker.rb      | 11 +++
 ...20230705232953_create_status_references.rb | 12 +++
 ...tatus_referred_by_count_to_status_stats.rb | 13 +++
 db/schema.rb                                  | 21 +++--
 24 files changed, 321 insertions(+), 7 deletions(-)
 create mode 100644 app/models/status_reference.rb
 create mode 100644 app/services/activitypub/fetch_references_service.rb
 create mode 100644 app/services/process_references_service.rb
 create mode 100644 app/workers/process_references_worker.rb
 create mode 100644 db/migrate/20230705232953_create_status_references.rb
 create mode 100644 db/migrate/20230706031715_add_status_referred_by_count_to_status_stats.rb

diff --git a/.rubocop.yml b/.rubocop.yml
index 0ca5405170..74f79611fb 100644
--- a/.rubocop.yml
+++ b/.rubocop.yml
@@ -109,6 +109,7 @@ Metrics/ParameterLists:
 Metrics/PerceivedComplexity:
   Exclude:
     - 'app/policies/status_policy.rb'
+    - 'app/services/post_status_service.rb'
 
 # Reason: Prevailing style is argument file paths
 # https://docs.rubocop.org/rubocop-rails/cops_rails.html#railsfilepath
diff --git a/app/javascript/mastodon/actions/notifications.js b/app/javascript/mastodon/actions/notifications.js
index c9def4962d..25e4410c65 100644
--- a/app/javascript/mastodon/actions/notifications.js
+++ b/app/javascript/mastodon/actions/notifications.js
@@ -143,6 +143,7 @@ const excludeTypesFromFilter = filter => {
     'favourite',
     'emoji_reaction',
     'reblog',
+    'status_reference',
     'mention',
     'poll',
     'status',
diff --git a/app/javascript/mastodon/features/notifications/components/column_settings.jsx b/app/javascript/mastodon/features/notifications/components/column_settings.jsx
index 0051f92ca7..e141039c96 100644
--- a/app/javascript/mastodon/features/notifications/components/column_settings.jsx
+++ b/app/javascript/mastodon/features/notifications/components/column_settings.jsx
@@ -152,6 +152,17 @@ export default class ColumnSettings extends PureComponent {
           </div>
         </div>
 
+        <div role='group' aria-labelledby='notifications-status_reference'>
+          <span id='notifications-status_reference' className='column-settings__section'><FormattedMessage id='notifications.column_settings.status_reference' defaultMessage='References:' /></span>
+
+          <div className='column-settings__row'>
+            <SettingToggle disabled={browserPermission === 'denied'} prefix='notifications_desktop' settings={settings} settingPath={['alerts', 'status_reference']} onChange={onChange} label={alertStr} />
+            {showPushSettings && <SettingToggle prefix='notifications_push' settings={pushSettings} settingPath={['alerts', 'status_reference']} onChange={this.onPushChange} label={pushStr} />}
+            <SettingToggle prefix='notifications' settings={settings} settingPath={['shows', 'status_reference']} onChange={onChange} label={showStr} />
+            <SettingToggle prefix='notifications' settings={settings} settingPath={['sounds', 'status_reference']} onChange={onChange} label={soundStr} />
+          </div>
+        </div>
+
         <div role='group' aria-labelledby='notifications-poll'>
           <span id='notifications-poll' className='column-settings__section'><FormattedMessage id='notifications.column_settings.poll' defaultMessage='Poll results:' /></span>
 
diff --git a/app/javascript/mastodon/features/notifications/components/filter_bar.jsx b/app/javascript/mastodon/features/notifications/components/filter_bar.jsx
index f8d5fbaa47..7fcd63e110 100644
--- a/app/javascript/mastodon/features/notifications/components/filter_bar.jsx
+++ b/app/javascript/mastodon/features/notifications/components/filter_bar.jsx
@@ -10,6 +10,7 @@ const tooltips = defineMessages({
   favourites: { id: 'notifications.filter.favourites', defaultMessage: 'Favourites' },
   emojiReactions: { id: 'notifications.filter.emoji_reactions', defaultMessage: 'Stamps' },
   boosts: { id: 'notifications.filter.boosts', defaultMessage: 'Boosts' },
+  status_references: { id: 'notifications.filter.status_references', defaultMessage: 'Status references' },
   polls: { id: 'notifications.filter.polls', defaultMessage: 'Poll results' },
   follows: { id: 'notifications.filter.follows', defaultMessage: 'Follows' },
   statuses: { id: 'notifications.filter.statuses', defaultMessage: 'Updates from people you follow' },
@@ -90,6 +91,13 @@ class FilterBar extends PureComponent {
         >
           <Icon id='retweet' fixedWidth />
         </button>
+        <button
+          className={selectedFilter === 'status_reference' ? 'active' : ''}
+          onClick={this.onClick('status_reference')}
+          title={intl.formatMessage(tooltips.status_references)}
+        >
+          <Icon id='retweet' fixedWidth />
+        </button>
         <button
           className={selectedFilter === 'poll' ? 'active' : ''}
           onClick={this.onClick('poll')}
diff --git a/app/javascript/mastodon/features/notifications/components/notification.jsx b/app/javascript/mastodon/features/notifications/components/notification.jsx
index 6bc5d8e5be..8f1c88558f 100644
--- a/app/javascript/mastodon/features/notifications/components/notification.jsx
+++ b/app/javascript/mastodon/features/notifications/components/notification.jsx
@@ -28,6 +28,7 @@ const messages = defineMessages({
   poll: { id: 'notification.poll', defaultMessage: 'A poll you have voted in has ended' },
   reblog: { id: 'notification.reblog', defaultMessage: '{name} boosted your status' },
   status: { id: 'notification.status', defaultMessage: '{name} just posted' },
+  statusReference: { id: 'notification.status_reference', defaultMessage: '{name} refered' },
   update: { id: 'notification.update', defaultMessage: '{name} edited a post' },
   adminSignUp: { id: 'notification.admin.sign_up', defaultMessage: '{name} signed up' },
   adminReport: { id: 'notification.admin.report', defaultMessage: '{name} reported {target}' },
@@ -288,6 +289,39 @@ class Notification extends ImmutablePureComponent {
     );
   }
 
+  renderStatusReference (notification, link) {
+    const { intl, unread } = this.props;
+
+    return (
+      <HotKeys handlers={this.getHandlers()}>
+        <div className={classNames('notification notification-reblog focusable', { unread })} tabIndex={0} aria-label={notificationForScreenReader(intl, intl.formatMessage(messages.reblog, { name: notification.getIn(['account', 'acct']) }), notification.get('created_at'))}>
+          <div className='notification__message'>
+            <div className='notification__favourite-icon-wrapper'>
+              <Icon id='retweet' fixedWidth />
+            </div>
+
+            <span title={notification.get('created_at')}>
+              <FormattedMessage id='notification.status_reference' defaultMessage='{name} referenced your status' values={{ name: link }} />
+            </span>
+          </div>
+
+          <StatusContainer
+            id={notification.get('status')}
+            account={notification.get('account')}
+            muted
+            withDismiss
+            hidden={this.props.hidden}
+            getScrollPosition={this.props.getScrollPosition}
+            updateScrollBottom={this.props.updateScrollBottom}
+            cachedMediaWidth={this.props.cachedMediaWidth}
+            cacheMediaWidth={this.props.cacheMediaWidth}
+            withoutEmojiReactions
+          />
+        </div>
+      </HotKeys>
+    );
+  }
+
   renderStatus (notification, link) {
     const { intl, unread, status } = this.props;
 
@@ -479,6 +513,8 @@ class Notification extends ImmutablePureComponent {
       return this.renderEmojiReaction(notification, link);
     case 'reblog':
       return this.renderReblog(notification, link);
+    case 'status_reference':
+      return this.renderStatusReference(notification, link);
     case 'status':
       return this.renderStatus(notification, link);
     case 'update':
diff --git a/app/javascript/mastodon/locales/ja.json b/app/javascript/mastodon/locales/ja.json
index 78d4b0aaea..16b6b71bf2 100644
--- a/app/javascript/mastodon/locales/ja.json
+++ b/app/javascript/mastodon/locales/ja.json
@@ -415,6 +415,7 @@
   "notification.poll": "アンケートが終了しました",
   "notification.reblog": "{name}さんがあなたの投稿をブーストしました",
   "notification.status": "{name}さんが投稿しました",
+  "notification.status_reference": "{name}さんがあなたの投稿を参照しました",
   "notification.update": "{name}さんが投稿を編集しました",
   "notifications.clear": "通知を消去",
   "notifications.clear_confirmation": "本当に通知を消去しますか？",
diff --git a/app/lib/activitypub/activity/create.rb b/app/lib/activitypub/activity/create.rb
index 13a5d11361..3dbdaf74fb 100644
--- a/app/lib/activitypub/activity/create.rb
+++ b/app/lib/activitypub/activity/create.rb
@@ -97,6 +97,7 @@ class ActivityPub::Activity::Create < ActivityPub::Activity
     fetch_replies(@status)
     distribute
     forward_for_reply
+    process_references!
     join_group!
   end
 
@@ -471,6 +472,12 @@ class ActivityPub::Activity::Create < ActivityPub::Activity
     retry
   end
 
+  def process_references!
+    references = []
+    references = ActivityPub::FetchReferencesService(@json['references']) unless @json['references'].nil?
+    ProcessReferencesWorker.perform_async(@status.id, [], urls: references)
+  end
+
   def join_group!
     GroupReblogService.new.call(@status)
   end
diff --git a/app/models/notification.rb b/app/models/notification.rb
index 4bee407ea9..eb56e32913 100644
--- a/app/models/notification.rb
+++ b/app/models/notification.rb
@@ -26,6 +26,7 @@ class Notification < ApplicationRecord
     'FollowRequest' => :follow_request,
     'Favourite' => :favourite,
     'EmojiReaction' => :emoji_reaction,
+    'StatusReference' => :status_reference,
     'Poll' => :poll,
   }.freeze
 
@@ -33,6 +34,7 @@ class Notification < ApplicationRecord
     mention
     status
     reblog
+    status_reference
     follow
     follow_request
     favourite
@@ -47,6 +49,7 @@ class Notification < ApplicationRecord
   TARGET_STATUS_INCLUDES_BY_TYPE = {
     status: :status,
     reblog: [status: :reblog],
+    status_reference: [status_reference: :status],
     mention: [mention: :status],
     favourite: [favourite: :status],
     emoji_reaction: [emoji_reaction: :status],
@@ -67,6 +70,7 @@ class Notification < ApplicationRecord
     belongs_to :follow_request, inverse_of: :notification
     belongs_to :favourite, inverse_of: :notification
     belongs_to :emoji_reaction, inverse_of: :notification
+    belongs_to :status_reference, inverse_of: :notification
     belongs_to :poll, inverse_of: false
     belongs_to :report, inverse_of: false
   end
@@ -85,6 +89,8 @@ class Notification < ApplicationRecord
       status
     when :reblog
       status&.reblog
+    when :status_reference
+      status_reference&.status
     when :favourite
       favourite&.status
     when :emoji_reaction, :reaction
@@ -136,6 +142,8 @@ class Notification < ApplicationRecord
           notification.status = cached_status
         when :reblog
           notification.status.reblog = cached_status
+        when :status_reference
+          notification.status_reference.status = cached_status
         when :favourite
           notification.favourite.status = cached_status
         when :emoji_reaction, :reaction
@@ -162,7 +170,7 @@ class Notification < ApplicationRecord
     case activity_type
     when 'Status', 'Follow', 'Favourite', 'EmojiReaction', 'EmojiReact', 'FollowRequest', 'Poll', 'Report'
       self.from_account_id = activity&.account_id
-    when 'Mention'
+    when 'Mention', 'StatusReference'
       self.from_account_id = activity&.status&.account_id
     when 'Account'
       self.from_account_id = activity&.id
diff --git a/app/models/status.rb b/app/models/status.rb
index fa4b4c5644..a4d7da8d6a 100644
--- a/app/models/status.rb
+++ b/app/models/status.rb
@@ -75,6 +75,10 @@ class Status < ApplicationRecord
   has_many :mentioned_accounts, through: :mentions, source: :account, class_name: 'Account'
   has_many :active_mentions, -> { active }, class_name: 'Mention', inverse_of: :status
   has_many :media_attachments, dependent: :nullify
+  has_many :reference_objects, class_name: 'StatusReference', inverse_of: :status
+  has_many :references, through: :reference_objects, class_name: 'Status', source: :target_status
+  has_many :referenced_by_status_objects, foreign_key: 'target_status_id', class_name: 'StatusReference', inverse_of: :target_status
+  has_many :referenced_by_statuses, through: :referenced_by_status_objects, class_name: 'Status', source: :status
 
   has_and_belongs_to_many :tags
   has_and_belongs_to_many :preview_cards
@@ -332,6 +336,10 @@ class Status < ApplicationRecord
     status_stat&.emoji_reaction_accounts_count || 0
   end
 
+  def status_referred_by_count
+    status_stat&.status_referred_by_count || 0
+  end
+
   def increment_count!(key)
     update_status_stat!(key => public_send(key) + 1)
   end
@@ -340,6 +348,10 @@ class Status < ApplicationRecord
     update_status_stat!(key => [public_send(key) - 1, 0].max)
   end
 
+  def add_status_referred_by_count!(diff)
+    update_status_stat!(status_referred_by_count: [public_send(:status_referred_by_count) + diff, 0].max)
+  end
+
   def emoji_reactions_grouped_by_name(account = nil)
     (Oj.load(status_stat&.emoji_reactions || '', mode: :strict) || []).tap do |emoji_reactions|
       if account.present?
diff --git a/app/models/status_reference.rb b/app/models/status_reference.rb
new file mode 100644
index 0000000000..2ed5b2aee9
--- /dev/null
+++ b/app/models/status_reference.rb
@@ -0,0 +1,25 @@
+# frozen_string_literal: true
+
+# == Schema Information
+#
+# Table name: status_references
+#
+#  id               :bigint(8)        not null, primary key
+#  status_id        :bigint(8)        not null
+#  target_status_id :bigint(8)        not null
+#  created_at       :datetime         not null
+#  updated_at       :datetime         not null
+#
+
+class StatusReference < ApplicationRecord
+  belongs_to :status
+  belongs_to :target_status, class_name: 'Status'
+
+  has_one :notification, as: :activity, dependent: :destroy
+
+  validate :validate_status_visibilities
+
+  def validate_status_visibilities
+    raise Mastodon::ValidationError, I18n.t('status_references.errors.invalid_status_visibilities') if [:public, :public_unlisted, :unlisted, :login].exclude?(target_status.visibility.to_sym)
+  end
+end
diff --git a/app/models/status_stat.rb b/app/models/status_stat.rb
index 107f8339d6..d2a29170a8 100644
--- a/app/models/status_stat.rb
+++ b/app/models/status_stat.rb
@@ -15,6 +15,7 @@
 #  emoji_reactions_count         :integer          default(0), not null
 #  test                          :integer          default(0), not null
 #  emoji_reaction_accounts_count :integer          default(0), not null
+#  status_referred_by_count      :integer          default(0), not null
 #
 
 class StatusStat < ApplicationRecord
@@ -46,6 +47,10 @@ class StatusStat < ApplicationRecord
     [attributes['emoji_reaction_accounts_count'], 0].max
   end
 
+  def status_referred_by_count
+    [attributes['status_referred_by_count'], 0].max
+  end
+
   private
 
   def reset_parent_cache
diff --git a/app/models/user.rb b/app/models/user.rb
index a0678117d4..ee99e497eb 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -40,6 +40,7 @@
 #  sign_up_ip                :inet
 #  role_id                   :bigint(8)
 #  settings                  :text
+#  time_zone                 :string
 #
 
 class User < ApplicationRecord
diff --git a/app/serializers/rest/instance_serializer.rb b/app/serializers/rest/instance_serializer.rb
index 7417826805..2dd360ab35 100644
--- a/app/serializers/rest/instance_serializer.rb
+++ b/app/serializers/rest/instance_serializer.rb
@@ -117,6 +117,7 @@ class REST::InstanceSerializer < ActiveModel::Serializer
       :kmyblue_markdown,
       :kmyblue_reaction_deck,
       :kmyblue_visibility_login,
+      :status_reference,
     ]
 
     capabilities << :profile_search unless Chewy.enabled?
diff --git a/app/serializers/rest/notification_serializer.rb b/app/serializers/rest/notification_serializer.rb
index 793d33b8c5..5a7d6e11b5 100644
--- a/app/serializers/rest/notification_serializer.rb
+++ b/app/serializers/rest/notification_serializer.rb
@@ -13,7 +13,7 @@ class REST::NotificationSerializer < ActiveModel::Serializer
   end
 
   def status_type?
-    [:favourite, :emoji_reaction, :reaction, :reblog, :status, :mention, :poll, :update].include?(object.type)
+    [:favourite, :emoji_reaction, :reaction, :reblog, :status_reference, :status, :mention, :poll, :update].include?(object.type)
   end
 
   def report_type?
diff --git a/app/serializers/rest/status_serializer.rb b/app/serializers/rest/status_serializer.rb
index 7b4ec35534..e31636ccb6 100644
--- a/app/serializers/rest/status_serializer.rb
+++ b/app/serializers/rest/status_serializer.rb
@@ -6,6 +6,7 @@ class REST::StatusSerializer < ActiveModel::Serializer
   attributes :id, :created_at, :in_reply_to_id, :in_reply_to_account_id,
              :sensitive, :spoiler_text, :visibility, :visibility_ex, :language,
              :uri, :url, :replies_count, :reblogs_count, :searchability, :markdown,
+             :status_reference_ids, :status_references_count, :status_referred_by_count,
              :favourites_count, :emoji_reactions, :emoji_reactions_count, :reactions, :edited_at
 
   attribute :favourited, if: :current_user?
@@ -92,6 +93,14 @@ class REST::StatusSerializer < ActiveModel::Serializer
     ActivityPub::TagManager.instance.url_for(object)
   end
 
+  def status_reference_ids
+    @status_reference_ids = object.reference_objects.pluck(:target_status_id)
+  end
+
+  def status_references_count
+    status_reference_ids.size
+  end
+
   def favourited
     if instance_options && instance_options[:relationships]
       instance_options[:relationships].favourites_map[object.id] || false
diff --git a/app/serializers/rest/v1/instance_serializer.rb b/app/serializers/rest/v1/instance_serializer.rb
index c887635d1e..c0c30b5a03 100644
--- a/app/serializers/rest/v1/instance_serializer.rb
+++ b/app/serializers/rest/v1/instance_serializer.rb
@@ -126,6 +126,7 @@ class REST::V1::InstanceSerializer < ActiveModel::Serializer
       :kmyblue_markdown,
       :kmyblue_reaction_deck,
       :kmyblue_visibility_login,
+      :status_reference,
     ]
 
     capabilities << :profile_search unless Chewy.enabled?
diff --git a/app/services/activitypub/fetch_references_service.rb b/app/services/activitypub/fetch_references_service.rb
new file mode 100644
index 0000000000..d6537e7467
--- /dev/null
+++ b/app/services/activitypub/fetch_references_service.rb
@@ -0,0 +1,49 @@
+# frozen_string_literal: true
+
+class ActivityPub::FetchReferencesService < BaseService
+  include JsonLdHelper
+
+  def call(status, collection_or_uri)
+    @account = status.account
+
+    collection_items(collection_or_uri)&.map { |item| value_or_id(item) }
+  end
+
+  private
+
+  def collection_items(collection_or_uri)
+    collection = fetch_collection(collection_or_uri)
+    return unless collection.is_a?(Hash) && collection['first'].present?
+
+    all_items = []
+    collection = fetch_collection(collection['first'])
+
+    while collection.is_a?(Hash)
+      items = begin
+        case collection['type']
+        when 'Collection', 'CollectionPage'
+          collection['items']
+        when 'OrderedCollection', 'OrderedCollectionPage'
+          collection['orderedItems']
+        end
+      end
+
+      break if items.blank?
+
+      all_items.concat(items)
+
+      break if all_items.size >= StatusReferenceValidator::LIMIT
+
+      collection = collection['next'].present? ? fetch_collection(collection['next']) : nil
+    end
+
+    all_items
+  end
+
+  def fetch_collection(collection_or_uri)
+    return collection_or_uri if collection_or_uri.is_a?(Hash)
+    return if invalid_origin?(collection_or_uri)
+
+    fetch_resource_without_id_validation(collection_or_uri, nil, true)
+  end
+end
diff --git a/app/services/post_status_service.rb b/app/services/post_status_service.rb
index bacb9579f5..e1d5ab2471 100644
--- a/app/services/post_status_service.rb
+++ b/app/services/post_status_service.rb
@@ -34,6 +34,7 @@ class PostStatusService < BaseService
   # @option [String] :idempotency Optional idempotency key
   # @option [Boolean] :with_rate_limit
   # @option [Enumerable] :allowed_mentions Optional array of expected mentioned account IDs, raises `UnexpectedMentionsError` if unexpected accounts end up in mentions
+  # @option [Enumerable] :status_reference_ids Optional array
   # @return [Status]
   def call(account, options = {})
     @account     = account
@@ -78,6 +79,7 @@ class PostStatusService < BaseService
     @markdown     = @options[:markdown] || false
     @scheduled_at = @options[:scheduled_at]&.to_datetime
     @scheduled_at = nil if scheduled_in_the_past?
+    @reference_ids = (@options[:status_reference_ids] || []).map(&:to_i).filter(&:positive?)
   rescue ArgumentError
     raise ActiveRecord::RecordInvalid
   end
@@ -146,6 +148,7 @@ class PostStatusService < BaseService
 
   def postprocess_status!
     process_hashtags_service.call(@status)
+    ProcessReferencesWorker.perform_async(@status.id, @reference_ids)
     Trends.tags.register(@status)
     LinkCrawlWorker.perform_async(@status.id)
     DistributionWorker.perform_async(@status.id)
@@ -221,6 +224,7 @@ class PostStatusService < BaseService
       media_attachments: @media || [],
       ordered_media_attachment_ids: (@options[:media_ids] || []).map(&:to_i) & @media.map(&:id),
       thread: @in_reply_to,
+      status_reference_ids: @status_reference_ids,
       poll_attributes: poll_attributes,
       sensitive: @sensitive,
       spoiler_text: @options[:spoiler_text] || '',
diff --git a/app/services/process_references_service.rb b/app/services/process_references_service.rb
new file mode 100644
index 0000000000..f61129eb4c
--- /dev/null
+++ b/app/services/process_references_service.rb
@@ -0,0 +1,86 @@
+# frozen_string_literal: true
+
+class ProcessReferencesService < BaseService
+  include Payloadable
+
+  DOMAIN = ENV['WEB_DOMAIN'] || ENV.fetch('LOCAL_DOMAIN', nil)
+  REFURL_EXP = /(RT|QT|BT|RN)((:)? +|:)(#{URI::DEFAULT_PARSER.make_regexp(%w(http https))})/
+  STATUSID_EXP = %r{(http|https)://#{DOMAIN}/@[a-zA-Z0-9]+/([0-9]{16,})}
+
+  def call(status, reference_parameters, save_records: true, urls: nil)
+    @status = status
+    @reference_parameters = reference_parameters || []
+    @save_records = save_records
+    @urls = urls || []
+
+    old_references
+
+    StatusReference.transaction do
+      remove_old_references
+      add_references
+
+      @status.save! if @save_records
+    end
+
+    create_notifications!
+  end
+
+  private
+
+  def references
+    @references = @reference_parameters + scan_text!
+  end
+
+  def old_references
+    @old_references = @status.references.pluck(:id)
+  end
+
+  def added_references
+    (references - old_references).uniq
+  end
+
+  def removed_references
+    (old_references - references).uniq
+  end
+
+  def scan_text!
+    text = @status.text.gsub(%r{</?[^>]*>}, '')
+    @scan_text = fetch_statuses!(text.scan(REFURL_EXP).pluck(3).uniq).map(&:id).uniq.filter { |status_id| !status_id.zero? }
+  end
+
+  def fetch_statuses!(urls)
+    (urls + @urls)
+      .map { |url| ResolveURLService.new.call(url) }
+      .filter { |status| status }
+  end
+
+  def add_references
+    return if added_references.empty?
+
+    @added_objects = []
+
+    statuses = Status.where(id: added_references)
+    statuses.each do |status|
+      @added_objects << @status.reference_objects.new(target_status: status)
+      status.increment_count!(:status_referred_by_count)
+    end
+  end
+
+  def create_notifications!
+    return if @added_objects.empty?
+
+    LocalNotificationWorker.push_bulk(@added_objects) do |ref|
+      [ref.target_status.account_id, ref.id, 'StatusReference', 'status_reference']
+    end
+  end
+
+  def remove_old_references
+    return if removed_references.empty?
+
+    statuses = Status.where(id: removed_references)
+    @status.reference_objects.where(target_status: statuses).destroy_all
+    statuses.each do |status|
+      status.decrement_count!(:status_referred_by_count)
+    end
+  end
+end
diff --git a/app/services/update_status_service.rb b/app/services/update_status_service.rb
index 6cae51f735..ec39059d3f 100644
--- a/app/services/update_status_service.rb
+++ b/app/services/update_status_service.rb
@@ -142,6 +142,7 @@ class UpdateStatusService < BaseService
   def update_metadata!
     ProcessHashtagsService.new.call(@status)
     ProcessMentionsService.new.call(@status)
+    ProcessReferencesWorker.perform_async(@status.id, (@options[:status_reference_ids] || []).map(&:to_i).filter(&:positive?))
   end
 
   def broadcast_updates!
diff --git a/app/workers/process_references_worker.rb b/app/workers/process_references_worker.rb
new file mode 100644
index 0000000000..edae2c6163
--- /dev/null
+++ b/app/workers/process_references_worker.rb
@@ -0,0 +1,11 @@
+# frozen_string_literal: true
+
+class ProcessReferencesWorker
+  include Sidekiq::Worker
+
+  def perform(status_id, ids, urls: nil)
+    ProcessReferencesService.new.call(Status.find(status_id), ids || [], urls: urls)
+  rescue ActiveRecord::RecordNotFound
+    true
+  end
+end
diff --git a/db/migrate/20230705232953_create_status_references.rb b/db/migrate/20230705232953_create_status_references.rb
new file mode 100644
index 0000000000..88669fda06
--- /dev/null
+++ b/db/migrate/20230705232953_create_status_references.rb
@@ -0,0 +1,12 @@
+# frozen_string_literal: true
+
+class CreateStatusReferences < ActiveRecord::Migration[6.1]
+  def change
+    create_table :status_references do |t|
+      t.belongs_to :status, null: false, foreign_key: { on_delete: :cascade }
+      t.belongs_to :target_status, null: false, foreign_key: { on_delete: :cascade, to_table: :statuses }
+      t.datetime :created_at, null: false
+      t.datetime :updated_at, null: false
+    end
+  end
+end
diff --git a/db/migrate/20230706031715_add_status_referred_by_count_to_status_stats.rb b/db/migrate/20230706031715_add_status_referred_by_count_to_status_stats.rb
new file mode 100644
index 0000000000..8836079984
--- /dev/null
+++ b/db/migrate/20230706031715_add_status_referred_by_count_to_status_stats.rb
@@ -0,0 +1,13 @@
+# frozen_string_literal: true
+
+class AddStatusReferredByCountToStatusStats < ActiveRecord::Migration[6.1]
+  def up
+    safety_assured do
+      add_column :status_stats, :status_referred_by_count, :integer, null: false, default: 0
+    end
+  end
+
+  def down
+    remove_column :status_stats, :status_referred_by_count
+  end
+end
diff --git a/db/schema.rb b/db/schema.rb
index 68a95c345e..60f032436e 100644
--- a/db/schema.rb
+++ b/db/schema.rb
@@ -1,5 +1,3 @@
-# rubocop:disable all
-
 # This file is auto-generated from the current state of the database. Instead
 # of editing this file, please use the migrations feature of Active Record to
 # incrementally modify your database, and then regenerate this schema definition.
@@ -12,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 2023_06_05_085710) do
+ActiveRecord::Schema.define(version: 2023_07_06_031715) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
@@ -346,6 +344,7 @@ ActiveRecord::Schema.define(version: 2023_06_05_085710) do
     t.datetime "created_at", null: false
     t.datetime "updated_at", null: false
     t.bigint "dump_file_size"
+    t.index ["user_id"], name: "index_backups_on_user_id"
   end
 
   create_table "blocks", force: :cascade do |t|
@@ -804,6 +803,7 @@ ActiveRecord::Schema.define(version: 2023_06_05_085710) do
     t.bigint "owner_id"
     t.boolean "confidential", default: true, null: false
     t.index ["owner_id", "owner_type"], name: "index_oauth_applications_on_owner_id_and_owner_type"
+    t.index ["superapp"], name: "index_oauth_applications_on_superapp", where: "(superapp = true)"
     t.index ["uid"], name: "index_oauth_applications_on_uid", unique: true
   end
 
@@ -1041,6 +1041,15 @@ ActiveRecord::Schema.define(version: 2023_06_05_085710) do
     t.index ["status_id"], name: "index_status_pins_on_status_id"
   end
 
+  create_table "status_references", force: :cascade do |t|
+    t.bigint "status_id", null: false
+    t.bigint "target_status_id", null: false
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.index ["status_id"], name: "index_status_references_on_status_id"
+    t.index ["target_status_id"], name: "index_status_references_on_target_status_id"
+  end
+
   create_table "status_stats", force: :cascade do |t|
     t.bigint "status_id", null: false
     t.bigint "replies_count", default: 0, null: false
@@ -1052,6 +1061,7 @@ ActiveRecord::Schema.define(version: 2023_06_05_085710) do
     t.integer "emoji_reactions_count", default: 0, null: false
     t.integer "test", default: 0, null: false
     t.integer "emoji_reaction_accounts_count", default: 0, null: false
+    t.integer "status_referred_by_count", default: 0, null: false
     t.index ["status_id"], name: "index_status_stats_on_status_id", unique: true
   end
 
@@ -1211,6 +1221,7 @@ ActiveRecord::Schema.define(version: 2023_06_05_085710) do
     t.boolean "skip_sign_in_token"
     t.bigint "role_id"
     t.text "settings"
+    t.string "time_zone"
     t.index ["account_id"], name: "index_users_on_account_id"
     t.index ["confirmation_token"], name: "index_users_on_confirmation_token", unique: true
     t.index ["created_by_application_id"], name: "index_users_on_created_by_application_id", where: "(created_by_application_id IS NOT NULL)"
@@ -1374,6 +1385,8 @@ ActiveRecord::Schema.define(version: 2023_06_05_085710) do
   add_foreign_key "status_edits", "statuses", on_delete: :cascade
   add_foreign_key "status_pins", "accounts", name: "fk_d4cb435b62", on_delete: :cascade
   add_foreign_key "status_pins", "statuses", on_delete: :cascade
+  add_foreign_key "status_references", "statuses", column: "target_status_id", on_delete: :cascade
+  add_foreign_key "status_references", "statuses", on_delete: :cascade
   add_foreign_key "status_stats", "statuses", on_delete: :cascade
   add_foreign_key "status_trends", "accounts", on_delete: :cascade
   add_foreign_key "status_trends", "statuses", on_delete: :cascade
@@ -1491,5 +1504,3 @@ ActiveRecord::Schema.define(version: 2023_06_05_085710) do
   add_index "follow_recommendations", ["account_id"], name: "index_follow_recommendations_on_account_id", unique: true
 
 end
-
-# rubocop:enable all