Add basic support for group actors (#12071)

* Show badge on group actor in WebUI

* Do not notify in case of  by following group actor

* If you mention group actor, also mention group actor followers

* Relax characters that can be used in username (same as Application)

* Revert "Relax characters that can be used in username (same as Application)"

This reverts commit 7e10a137b878d0db1b5252c52106faef5e09ca4b.

* Delete display_name method

7 files changed, 117 insertions, 9 deletions

diff --git a/app/helpers/statuses_helper.rb b/app/helpers/statuses_helper.rb
index 866a9902c..f0e3df944 100644
--- a/app/helpers/statuses_helper.rb
+++ b/app/helpers/statuses_helper.rb
@@ -4,6 +4,74 @@ module StatusesHelper
   EMBEDDED_CONTROLLER = 'statuses'
   EMBEDDED_ACTION = 'embed'
 
+  def account_action_button(account)
+    if user_signed_in?
+      if account.id == current_user.account_id
+        link_to settings_profile_url, class: 'button logo-button' do
+          safe_join([svg_logo, t('settings.edit_profile')])
+        end
+      elsif current_account.following?(account) || current_account.requested?(account)
+        link_to account_unfollow_path(account), class: 'button logo-button button--destructive', data: { method: :post } do
+          safe_join([svg_logo, t('accounts.unfollow')])
+        end
+      elsif !(account.memorial? || account.moved?)
+        link_to account_follow_path(account), class: "button logo-button#{account.blocking?(current_account) ? ' disabled' : ''}", data: { method: :post } do
+          safe_join([svg_logo, t('accounts.follow')])
+        end
+      end
+    elsif !(account.memorial? || account.moved?)
+      link_to account_remote_follow_path(account), class: 'button logo-button modal-button', target: '_new' do
+        safe_join([svg_logo, t('accounts.follow')])
+      end
+    end
+  end
+
+  def minimal_account_action_button(account)
+    if user_signed_in?
+      return if account.id == current_user.account_id
+
+      if current_account.following?(account) || current_account.requested?(account)
+        link_to account_unfollow_path(account), class: 'icon-button active', data: { method: :post }, title: t('accounts.unfollow') do
+          fa_icon('user-times fw')
+        end
+      elsif !(account.memorial? || account.moved?)
+        link_to account_follow_path(account), class: "icon-button#{account.blocking?(current_account) ? ' disabled' : ''}", data: { method: :post }, title: t('accounts.follow') do
+          fa_icon('user-plus fw')
+        end
+      end
+    elsif !(account.memorial? || account.moved?)
+      link_to account_remote_follow_path(account), class: 'icon-button modal-button', target: '_new', title: t('accounts.follow') do
+        fa_icon('user-plus fw')
+      end
+    end
+  end
+
+  def svg_logo
+    content_tag(:svg, tag(:use, 'xlink:href' => '#mastodon-svg-logo'), 'viewBox' => '0 0 216.4144 232.00976')
+  end
+
+  def svg_logo_full
+    content_tag(:svg, tag(:use, 'xlink:href' => '#mastodon-svg-logo-full'), 'viewBox' => '0 0 713.35878 175.8678')
+  end
+
+  def account_badge(account, all: false)
+    if account.bot?
+      content_tag(:div, content_tag(:div, t('accounts.roles.bot'), class: 'account-role bot'), class: 'roles')
+    elsif account.group?
+      content_tag(:div, content_tag(:div, t('accounts.roles.group'), class: 'account-role group'), class: 'roles')
+    elsif (Setting.show_staff_badge && account.user_staff?) || all
+      content_tag(:div, class: 'roles') do
+        if all && !account.user_staff?
+          content_tag(:div, t('admin.accounts.roles.user'), class: 'account-role')
+        elsif account.user_admin?
+          content_tag(:div, t('accounts.roles.admin'), class: 'account-role admin')
+        elsif account.user_moderator?
+          content_tag(:div, t('accounts.roles.moderator'), class: 'account-role moderator')
+        end
+      end
+    end
+  end
+
   def link_to_more(url)
     link_to t('statuses.show_more'), url, class: 'load-more load-gap'
   end
diff --git a/app/javascript/mastodon/features/account/components/header.js b/app/javascript/mastodon/features/account/components/header.js
index dbb567e85..8bd7f2db5 100644
--- a/app/javascript/mastodon/features/account/components/header.js
+++ b/app/javascript/mastodon/features/account/components/header.js
@@ -238,9 +238,18 @@ class Header extends ImmutablePureComponent {
     const content         = { __html: account.get('note_emojified') };
     const displayNameHtml = { __html: account.get('display_name_html') };
     const fields          = account.get('fields');
-    const badge           = account.get('bot') ? (<div className='account-role bot'><FormattedMessage id='account.badges.bot' defaultMessage='Bot' /></div>) : null;
     const acct            = account.get('acct').indexOf('@') === -1 && domain ? `${account.get('acct')}@${domain}` : account.get('acct');
 
+    let badge;
+
+    if (account.get('bot')) {
+      badge = (<div className='account-role bot'><FormattedMessage id='account.badges.bot' defaultMessage='Bot' /></div>);
+    } else if (account.get('group')) {
+      badge = (<div className='account-role group'><FormattedMessage id='account.badges.group' defaultMessage='Group' /></div>);
+    } else {
+      badge = null;
+    }
+
     return (
       <div className={classNames('account__header', { inactive: !!account.get('moved') })} ref={this.setRef}>
         <div className='account__header__image'>
diff --git a/app/lib/activitypub/activity.rb b/app/lib/activitypub/activity.rb
index cdd406043..0ca6b92a4 100644
--- a/app/lib/activitypub/activity.rb
+++ b/app/lib/activitypub/activity.rb
@@ -89,7 +89,7 @@ class ActivityPub::Activity
   def distribute(status)
     crawl_links(status)
 
-    notify_about_reblog(status) if reblog_of_local_account?(status)
+    notify_about_reblog(status) if reblog_of_local_account?(status) && !reblog_by_following_group_account?(status)
     notify_about_mentions(status)
 
     # Only continue if the status is supposed to have arrived in real-time.
@@ -105,6 +105,10 @@ class ActivityPub::Activity
     status.reblog? && status.reblog.account.local?
   end
 
+  def reblog_by_following_group_account?(status)
+    status.reblog? && status.account.group? && status.reblog.account.following?(status.account)
+  end
+
   def notify_about_reblog(status)
     NotifyService.new.call(status.reblog.account, status)
   end
diff --git a/app/lib/activitypub/tag_manager.rb b/app/lib/activitypub/tag_manager.rb
index 512272dbe..ed680d762 100644
--- a/app/lib/activitypub/tag_manager.rb
+++ b/app/lib/activitypub/tag_manager.rb
@@ -68,10 +68,19 @@ class ActivityPub::TagManager
       if status.account.silenced?
         # Only notify followers if the account is locally silenced
         account_ids = status.active_mentions.pluck(:account_id)
-        to = status.account.followers.where(id: account_ids).map { |account| uri_for(account) }
-        to.concat(FollowRequest.where(target_account_id: status.account_id, account_id: account_ids).map { |request| uri_for(request.account) })
+        to = status.account.followers.where(id: account_ids).each_with_object([]) do |account, result|
+          result << uri_for(account)
+          result << account.followers_url if account.group?
+        end
+        to.concat(FollowRequest.where(target_account_id: status.account_id, account_id: account_ids).each_with_object([]) do |request, result|
+          result << uri_for(request.account)
+          result << request.account.followers_url if request.account.group?
+        end)
       else
-        status.active_mentions.map { |mention| uri_for(mention.account) }
+        status.active_mentions.each_with_object([]) do |mention, result|
+          result << uri_for(mention.account)
+          result << mention.account.followers_url if mention.account.group?
+        end
       end
     end
   end
@@ -97,10 +106,19 @@ class ActivityPub::TagManager
       if status.account.silenced?
         # Only notify followers if the account is locally silenced
         account_ids = status.active_mentions.pluck(:account_id)
-        cc.concat(status.account.followers.where(id: account_ids).map { |account| uri_for(account) })
-        cc.concat(FollowRequest.where(target_account_id: status.account_id, account_id: account_ids).map { |request| uri_for(request.account) })
+        cc.concat(status.account.followers.where(id: account_ids).each_with_object([]) do |account, result|
+          result << uri_for(account)
+          result << account.followers_url if account.group?
+        end)
+        cc.concat(FollowRequest.where(target_account_id: status.account_id, account_id: account_ids).each_with_object([]) do |request, result|
+          result << uri_for(request.account)
+          result << request.account.followers_url if request.account.group?
+        end)
       else
-        cc.concat(status.active_mentions.map { |mention| uri_for(mention.account) })
+        cc.concat(status.active_mentions.each_with_object([]) do |mention, result|
+          result << uri_for(mention.account)
+          result << mention.account.followers_url if mention.account.group?
+        end)
       end
     end
 
diff --git a/app/models/account.rb b/app/models/account.rb
index d17782f78..884332e5a 100644
--- a/app/models/account.rb
+++ b/app/models/account.rb
@@ -93,6 +93,7 @@ class Account < ApplicationRecord
   scope :without_silenced, -> { where(silenced_at: nil) }
   scope :recent, -> { reorder(id: :desc) }
   scope :bots, -> { where(actor_type: %w(Application Service)) }
+  scope :groups, -> { where(actor_type: 'Group') }
   scope :alphabetic, -> { order(domain: :asc, username: :asc) }
   scope :by_domain_accounts, -> { group(:domain).select(:domain, 'COUNT(*) AS accounts_count').order('accounts_count desc') }
   scope :matches_username, ->(value) { where(arel_table[:username].matches("#{value}%")) }
@@ -153,6 +154,12 @@ class Account < ApplicationRecord
     self.actor_type = ActiveModel::Type::Boolean.new.cast(val) ? 'Service' : 'Person'
   end
 
+  def group?
+    actor_type == 'Group'
+  end
+
+  alias group group?
+
   def acct
     local? ? username : "#{username}@#{domain}"
   end
diff --git a/app/serializers/activitypub/actor_serializer.rb b/app/serializers/activitypub/actor_serializer.rb
index 17df85de3..aa64936a7 100644
--- a/app/serializers/activitypub/actor_serializer.rb
+++ b/app/serializers/activitypub/actor_serializer.rb
@@ -49,6 +49,8 @@ class ActivityPub::ActorSerializer < ActivityPub::Serializer
       'Application'
     elsif object.bot?
       'Service'
+    elsif object.group?
+      'Group'
     else
       'Person'
     end
diff --git a/app/serializers/rest/account_serializer.rb b/app/serializers/rest/account_serializer.rb
index 7e3041ae3..5fec75673 100644
--- a/app/serializers/rest/account_serializer.rb
+++ b/app/serializers/rest/account_serializer.rb
@@ -3,7 +3,7 @@
 class REST::AccountSerializer < ActiveModel::Serializer
   include RoutingHelper
 
-  attributes :id, :username, :acct, :display_name, :locked, :bot, :discoverable, :created_at,
+  attributes :id, :username, :acct, :display_name, :locked, :bot, :discoverable, :group, :created_at,
              :note, :url, :avatar, :avatar_static, :header, :header_static,
              :followers_count, :following_count, :statuses_count, :last_status_at