Add: #8 サークル投稿の転送 (#294)

* Add: `conversations`テーブルに`ancestor_status`プロパティ

* Fix test

* Fix test more

* Add: `limited_visibility`に`Reply`を追加、`context`のURI

* Add: 外部からの`context`受信処理

* Fix test

* Add: 公開範囲「返信」

* Fix test

* Fix: 返信に返信以外の公開範囲を設定できない問題

* Add: ローカル投稿時にメンション追加・他サーバーへの転送

* Fix test

* Fix test

* Test: ローカルスレッドへの返信投稿の転送

* Test: 未知のアカウントからのメンション

* Add: 編集・削除の連合に対応

* Remove: 重複テスト

* Fix: 改善

* Add: 編集削除の転送処理・返信なのにsilentなメンションでの通知

* Fix: リプライが第三者に届かない問題

* Add: `always_sign_unsafe`

* Add: Subject

* Remove space

* Fix: 他人のスレッドの送信先一覧を非表示

* Fix: おかしいコード

app/lib/activitypub/activity/create.rb

@@ -93,6 +93,7 @@ class ActivityPub::Activity::Create < ActivityPub::Activity
 
     resolve_thread(@status)
     fetch_replies(@status)
+    process_conversation! if @status.limited_visibility?
     process_references!
     distribute
     forward_for_reply
@@ -132,7 +133,7 @@ class ActivityPub::Activity::Create < ActivityPub::Activity
       limited_scope: @status_parser.limited_scope,
       searchability: @status_parser.searchability,
       thread: replied_to_status,
-      conversation: conversation_from_uri(@object['conversation']),
+      conversation: conversation_from_activity,
       media_attachment_ids: process_attachments.take(MediaAttachment::ACTIVITYPUB_STATUS_ATTACHMENT_MAX).map(&:id),
       poll: process_poll,
     }
@@ -184,6 +185,10 @@ class ActivityPub::Activity::Create < ActivityPub::Activity
     @silenced_account_ids = @mentions.map(&:account_id) - accounts_in_audience.map(&:id)
   end
 
+  def account_representative
+    accounts_in_audience.detect(&:local?) || Account.representative
+  end
+
   def postprocess_audience_and_deliver
     return if @status.mentions.find_by(account_id: @options[:delivered_to_account_id])
 
@@ -373,6 +378,10 @@ class ActivityPub::Activity::Create < ActivityPub::Activity
     ActivityPub::FetchRepliesWorker.perform_async(status.id, uri, { 'request_id' => @options[:request_id] }) unless uri.nil?
   end
 
+  def conversation_from_activity
+    conversation_from_context(@object['context']) || conversation_from_uri(@object['conversation'])
+  end
+
   def conversation_from_uri(uri)
     return nil if uri.nil?
     return Conversation.find_by(id: OStatus::TagManager.instance.unique_tag_to_local_id(uri, 'Conversation')) if OStatus::TagManager.instance.local_id?(uri)
@@ -384,6 +393,26 @@ class ActivityPub::Activity::Create < ActivityPub::Activity
     end
   end
 
+  def conversation_from_context(uri)
+    return nil if uri.nil?
+    return Conversation.find_by(id: ActivityPub::TagManager.instance.uri_to_local_id(uri)) if ActivityPub::TagManager.instance.local_uri?(uri)
+
+    begin
+      conversation = Conversation.find_or_create_by!(uri: uri)
+
+      json = fetch_resource_without_id_validation(uri, account_representative)
+      return conversation if json.nil? || json['type'] != 'Group'
+      return conversation if json['inbox'].blank? || json['inbox'] == conversation.inbox_url
+
+      conversation.update!(inbox_url: json['inbox'])
+      conversation
+    rescue ActiveRecord::RecordInvalid, ActiveRecord::RecordNotUnique
+      retry
+    rescue Mastodon::UnexpectedResponseError
+      Conversation.find_or_create_by!(uri: uri)
+    end
+  end
+
   def replied_to_status
     return @replied_to_status if defined?(@replied_to_status)
 
@@ -483,6 +512,16 @@ class ActivityPub::Activity::Create < ActivityPub::Activity
     ActivityPub::RawDistributionWorker.perform_async(Oj.dump(@json), replied_to_status.account_id, [@account.preferred_inbox_url])
   end
 
+  def process_conversation!
+    return unless @status.conversation.present? && @status.conversation.local?
+
+    ProcessConversationService.new.call(@status)
+
+    return if @json['signature'].blank?
+
+    ActivityPub::ForwardConversationWorker.perform_async(Oj.dump(@json), @status.id, false)
+  end
+
   def increment_voters_count!
     poll = replied_to_status.preloadable_poll