AI: address review on PR #477

Reviewed-on: #452
Co-authored-by: miteruzo <miteruzo@naver.com>

backend/app/controllers/tag_descriptions_controller.rb

@@ -1,4 +1,34 @@
 class TagDescriptionsController < ApplicationController
+  rescue_from TagDescriptionOperation::Conflict, with: :render_conflict
+
+  def index
+    locale = resolve_locale!
+    descriptions = HistoryAccess.current(TagDescription.all, TagDescriptionVersion)
+        .where(language_code: locale.language_code).includes(tag: :tag_names)
+        .order(updated_at: :desc, id: :asc)
+    title = params[:title].to_s.strip
+    if title.present?
+      pattern = "%#{ ApplicationRecord.sanitize_sql_like(title) }%"
+      descriptions = descriptions.joins(tag: :tag_names)
+          .where(tag_names: { language_code: locale.language_code, primary_flg: true })
+          .where('tag_names.name LIKE ?', pattern).limit(20)
+    end
+    render json: descriptions.map { WikiPageRepr.tag_description(locale, _1) }
+  end
+
+  def show_by_id
+    locale = resolve_locale!
+    reference = TagDescription.find_by(id: params[:description_id])
+    return head :not_found unless reference
+
+    HistoryAccess.require_current!(reference, TagDescriptionVersion)
+    description = TagDescription.find_by(tag_id: reference.tag_id,
+                                         language_code: locale.language_code)
+    return head :not_found unless description
+
+    render json: representation(description)
+  end
+
   def show
     locale = resolve_locale!
     description = TagDescription.find_by(tag_id: params[:id], language_code: locale.language_code)
@@ -18,6 +48,25 @@ class TagDescriptionsController < ApplicationController
     render json: representation(description)
   end
 
+  def create
+    return head :unauthorized unless current_user
+    return head :forbidden unless current_user.gte_member?
+
+    locale = resolve_locale!
+    title = params[:title].to_s.strip
+    body = params[:body].to_s
+    return render_unprocessable_entity('タイトルは必須です．', field: :title) if title.blank?
+    return render_unprocessable_entity('本文は必須です．', field: :body) if body.blank?
+    return render_unprocessable_entity field: :title if title.include?(':')
+
+    tag_name = TagName.find_by(language_code: locale.language_code, name: title)
+    return render_unprocessable_entity field: :title unless tag_name&.tag
+
+    description = TagDescriptionOperation.create!(
+        locale, tag: tag_name.tag, body:, created_by_user: current_user)
+    render json: representation(description), status: :created
+  end
+
   def update
     return head :unauthorized unless current_user
     return head :forbidden unless current_user.gte_member?
@@ -32,7 +81,9 @@ class TagDescriptionsController < ApplicationController
     description = TagDescription.find_by(tag:, language_code: locale.language_code)
 
     if description
-      TagDescriptionOperation.update!(locale, tag:, body:, updated_by_user: current_user)
+      TagDescriptionOperation.update_with_title!(
+          locale, tag:, body:, title: params[:title], actor: current_user,
+          base_revision_id: params[:base_revision_id].presence)
       description.reload
       render json: representation(description)
     else
@@ -48,8 +99,20 @@ class TagDescriptionsController < ApplicationController
 
   private
 
+  def render_conflict error
+    render json: { error: 'conflict', message: error.message }, status: :conflict
+  end
+
   def representation description
     HistoryAccess.require_current!(description, TagDescriptionVersion)
+    if params[:document] == '1'
+      locale = resolve_locale!
+      version = HistoryAccess.visible(TagDescriptionVersion.all).find_by!(
+          tag_id: description.tag_id, language_code: description.language_code,
+          version_no: description.version_no)
+      return WikiPageRepr.tag_description(locale, description).merge(revision_id: version.id)
+    end
+
     description.as_json(only: [
         :tag_id,
         :language_code,

backend/app/controllers/tag_groups_controller.rb

@@ -1,7 +1,22 @@
 class TagGroupsController < ApplicationController
+  rescue_from TagGroupMarkdownParser::InvalidDocument,
+              TagGroupMarkdownRenderer::UnsupportedStructure, with: :render_document_error
+
   def index
     locale = resolve_locale!
-    groups = HistoryAccess.current(TagGroup.all, TagGroupVersion).includes(:created_by_user, :updated_by_user).order(:id)
+    groups = HistoryAccess.current(TagGroup.all, TagGroupVersion)
+        .includes(:created_by_user, :updated_by_user)
+    if params[:document] == '1'
+      groups = groups.order(updated_at: :desc, id: :asc)
+      title = params[:title].to_s.strip
+      if title.present?
+        pattern = "%#{ ApplicationRecord.sanitize_sql_like(title) }%"
+        groups = groups.where('CONCAT(?, name) LIKE ? OR CONCAT(?, name) LIKE ?',
+                              TagGroupRepr::PREFIX, pattern, 'tag_group:', pattern).limit(20)
+      end
+      return render json: groups.map { WikiPageRepr.tag_group(_1) }
+    end
+    groups = groups.order(:id)
     render json: TagGroupRepr.many(locale, groups.to_a)
   end
 
@@ -10,7 +25,15 @@ class TagGroupsController < ApplicationController
     group = TagGroup.includes(:created_by_user, :updated_by_user).find_by(id: params[:id])
     return head :not_found unless group
 
-    render json: TagGroupRepr.one(locale, group)
+    render json: representation(locale, group)
+  end
+
+  def show_by_name
+    locale = resolve_locale!
+    group = TagGroup.includes(:created_by_user, :updated_by_user).find_by(name: params[:name])
+    return head :not_found unless group
+
+    render json: representation(locale, group)
   end
 
   def create
@@ -18,8 +41,8 @@ class TagGroupsController < ApplicationController
     return head :forbidden unless current_user.gte_member?
 
     locale = resolve_locale!
-    group = TagGroupOperation.create!(locale, **write_attributes, actor: current_user)
+    group = TagGroupOperation.create!(locale, **write_attributes(locale), actor: current_user)
-    render json: TagGroupRepr.one(locale, group), status: :created
+    render json: representation(locale, group), status: :created
   end
 
   def update
@@ -30,13 +53,39 @@ class TagGroupsController < ApplicationController
     group = TagGroup.find_by(id: params[:id])
     return head :not_found unless group
 
-    TagGroupOperation.update!(locale, group:, **write_attributes, actor: current_user)
+    TagGroupOperation.update!(locale, group:, **write_attributes(locale, group:), actor: current_user)
-    render json: TagGroupRepr.one(locale, group.reload)
+    render json: representation(locale, group.reload)
   end
 
   private
 
-  def write_attributes
+  def render_document_error error
+    render_unprocessable_entity(error.message)
+  end
+
+  def representation locale, group
+    representation = TagGroupRepr.one(locale, group)
+    return representation unless params[:document] == '1'
+
+    version = TagGroupRepr.current_version(group)
+    raise ActiveRecord::RecordNotFound unless version
+
+    TagGroupRepr.document(representation, version)
+  end
+
+  def write_attributes locale, group: nil
+    if params.key?(:body)
+      body = params[:body].to_s
+      if body.blank?
+        group ||= TagGroup.new
+        group.errors.add(:body, :blank)
+        raise ActiveRecord::RecordInvalid, group
+      end
+      parsed = TagGroupMarkdownParser.parse(locale, body:, group:)
+      return parsed.except(:compatibility_body).merge(
+          name: params[:name], require_compatibility: true)
+    end
+
     { name: params[:name], description: params[:description],
       members: params[:members], placements: params[:placements] }
   end

backend/app/controllers/wiki_pages_controller.rb

@@ -6,6 +6,11 @@ class WikiPagesController < ApplicationController
   def index
     locale = resolve_locale!
 
+    resource_type = params[:resource_type]
+    unless resource_type.nil? || ['tag_description', 'tag_group'].include?(resource_type)
+      return head :bad_request
+    end
+
     title = params[:title].to_s.strip
     descriptions =
         HistoryAccess.current(TagDescription.all, TagDescriptionVersion)
@@ -14,6 +19,8 @@ class WikiPagesController < ApplicationController
 
     descriptions = descriptions.order(updated_at: :desc, id: :asc)
     tag_groups = HistoryAccess.current(TagGroup.all, TagGroupVersion).order(updated_at: :desc, id: :asc)
+    descriptions = descriptions.none if resource_type == 'tag_group'
+    tag_groups = tag_groups.none if resource_type == 'tag_description'
     if title.present?
       pattern = "%#{ ApplicationRecord.sanitize_sql_like(title) }%"
       descriptions =
@@ -246,25 +253,8 @@ class WikiPagesController < ApplicationController
 
     base_revision_id = params[:base_revision_id].presence
 
-    ApplicationRecord.transaction do
+    TagDescriptionOperation.update_with_title!(
-      SharedResourceIdAllocator.lock_space!(Tag, 'tags')
+        locale, tag:, body:, title:, actor: current_user, base_revision_id:)
-      tag.lock!
-      old_title = tag_name.name
-      if title != old_title
-        TagVersioning.ensure_snapshot!(tag, created_by_user: current_user)
-      end
-
-      tag_name.update!(name: title) if title != old_title
-
-      message = params[:message].presence
-      TagDescriptionOperation.update!(locale, tag:, body:, updated_by_user: current_user,
-                                      message:, base_revision_id:)
-
-      if title != old_title
-        tag.reload
-        TagVersionRecorder.record!(tag:, event_type: :update, created_by_user: current_user)
-      end
-    end
 
     head :ok
   rescue ActiveRecord::RecordInvalid => e
@@ -326,21 +316,9 @@ class WikiPagesController < ApplicationController
   end
 
   def render_group_representation representation, version, body: nil, status: :ok
-    body ||= TagGroupMarkdownRenderer.render(representation)
+    document = TagGroupRepr.document(representation, version)
-    versions = HistoryAccess.visible(TagGroupVersion.all).where(tag_group_id: version.tag_group_id)
+    document['body'] = body if body
-    pred = versions.find_by(version_no: version.version_no - 1)&.id
+    render json: document, status:
-    succ = versions.find_by(version_no: version.version_no + 1)&.id
-    updated_at = version.created_at
-    render json: {
-        'id' => version.tag_group_id,
-        'resource_type' => 'tag_group',
-        'title' => "#{ TagGroupRepr::PREFIX }#{ representation.fetch('name') }",
-        'deprecated_at' => nil,
-        'body' => body,
-        'revision_id' => version.id,
-        'pred' => pred,
-        'succ' => succ,
-        'updated_at' => updated_at }, status:
   rescue TagGroupMarkdownRenderer::UnsupportedStructure => error
     render_unprocessable_entity(error.message)
   end

backend/app/models/history_access.rb

@@ -4,7 +4,7 @@ require 'digest'
 class HistoryAccess < ActiveSupport::CurrentAttributes
   attribute :user
   class Forbidden < StandardError; end
-  ARTIFACT_POLICY = 'counts-masked-summary-1'.freeze
+  ARTIFACT_POLICY = 'counts-private-predicates-4'.freeze
 
   KEYS = { 'post_versions' => ['post_id'], 'tag_versions' => ['tag_id'],
            'nico_tag_versions' => ['tag_id'],

backend/app/representations/tag_group_repr.rb

@@ -56,6 +56,21 @@ module TagGroupRepr
       'updated_at' => wiki_page.updated_at }
   end
 
+  def document representation, version
+    HistoryAccess.require!(version)
+    versions = HistoryAccess.visible(TagGroupVersion.all)
+        .where(tag_group_id: version.tag_group_id)
+    { 'id' => version.tag_group_id,
+      'resource_type' => 'tag_group',
+      'title' => "#{ PREFIX }#{ representation.fetch('name') }",
+      'deprecated_at' => nil,
+      'body' => TagGroupMarkdownRenderer.render(representation),
+      'revision_id' => version.id,
+      'pred' => versions.find_by(version_no: version.version_no - 1)&.id,
+      'succ' => versions.find_by(version_no: version.version_no + 1)&.id,
+      'updated_at' => version.created_at }
+  end
+
   def current_version group
     HistoryAccess.visible(TagGroupVersion.all).find_by(tag_group_id: group.id, version_no: group.version_no)
   end

backend/app/services/counts_axes.rb

@@ -1,12 +1,41 @@
 class CountsAxes
   MAX_AXES = 8
+  MASKED_TEXT = '********'.freeze
   MASKED_VALUE = '__counts_private__'.freeze
-  PUBLIC_FIELDS = ['created_at', 'event_type'].freeze
+  PUBLIC_FIELDS = ['resource_id', 'version_no', 'event_type', 'user',
+                   'created_at'].freeze
   class TooManyAxes < ArgumentError; end
   class PrivateCondition < ArgumentError; end
 
   GRAINS = ['year', 'quarter', 'month', 'week', 'day', 'hour'].freeze
 
+  def self.private_field?(field)
+    !PUBLIC_FIELDS.include?(field) && field != 'user.id'
+  end
+
+  def self.visible_ids_sql(definition)
+    "SELECT counts_visible.id FROM #{ definition.table } counts_visible WHERE " +
+        HistoryAccess.sql(definition.model, 'counts_visible')
+  end
+
+  def self.visibility_sql(definition, field)
+    return 'TRUE' if HistoryAccess.admin?
+
+    source = visible_ids_sql(definition)
+    visible = "v.id IN (#{ source })"
+    return visible unless field == 'changed_field'
+
+    "(#{ visible }) AND (previous.id IS NULL OR previous.id IN (#{ source }))"
+  end
+
+  def self.masked_sql(expression, definition, field)
+    return expression if HistoryAccess.admin? || !private_field?(field)
+
+    visible = visibility_sql(definition, field)
+    quoted = ApplicationRecord.connection.quote(MASKED_VALUE)
+    "CASE WHEN #{ visible } THEN #{ expression } ELSE #{ quoted } END"
+  end
+
   def self.time_expression(expression, grain, timezone)
     raise ArgumentError unless GRAINS.include?(grain)
 
@@ -60,13 +89,9 @@ class CountsAxes
         @definition.fields[field] == :datetime ? self.class.time_expression(
             expression, axis.fetch('grain', 'month'), @population.timezone) : expression
       end
-      if !HistoryAccess.admin? && !PUBLIC_FIELDS.include?(field)
+      if !HistoryAccess.admin? && self.class.private_field?(field)
-        visible = HistoryAccess.sql(@definition.model, 'v')
+        expression = self.class.masked_sql(
-        if field == 'changed_field'
+            "CAST((#{ expression }) AS CHAR)", @definition, field)
-          visible = "(#{ visible }) AND (#{ HistoryAccess.sql(@definition.model, 'previous') })"
-        end
-        expression = "CASE WHEN #{ visible } " +
-            "THEN CAST((#{ expression }) AS CHAR) ELSE '#{ MASKED_VALUE }' END"
       end
       expression
     end
@@ -77,10 +102,12 @@ class CountsAxes
     selected = indexes.map { "#{ expressions[_1] } AS a#{ _1 }" }
     identities = ['v.id']
     if rows.any? { _1['field'] == 'tags' }
-      # Raw identities stay inside COUNT; masked tag occurrences remain additive.
+      identities << self.class.masked_sql(
-      identities << "COALESCE(CONCAT('internal:', tag_entry.tag_id), " +
+          "COALESCE(CONCAT('internal:', tag_entry.tag_id), " +
-          "CONCAT('external:', tag_entry.external_tag_id))"
+              "CONCAT('external:', tag_entry.external_tag_id))", @definition, 'tags')
-      identities << 'changed.field_key' if rows.any? { _1['field'] == 'changed_field' }
+      if rows.any? { _1['field'] == 'changed_field' }
+        identities << self.class.masked_sql('changed.field_key', @definition, 'changed_field')
+      end
     end
     members = identities.each_index.map { "counts_member_#{ _1 }" }
     selected += identities.each_with_index.map { |expression, index|
@@ -98,8 +125,17 @@ class CountsAxes
   def joins(fields = all.map { _1['field'] })
     result = ''
     if fields.include?('tags')
+      document = 'CAST(v.tags_json AS JSON)'
+      unless HistoryAccess.admin?
+        visible = self.class.visible_ids_sql(@definition)
+        result += " LEFT JOIN (#{ visible }) counts_tags_visible " +
+            'ON counts_tags_visible.id = v.id '
+        document = "CASE WHEN counts_tags_visible.id IS NOT NULL " +
+            "THEN #{ document } ELSE JSON_ARRAY(" +
+            "JSON_OBJECT('tag_id', 0)) END"
+      end
       result += <<~SQL.squish
-         JOIN JSON_TABLE(CAST(v.tags_json AS JSON), '$[*]' COLUMNS (
+         JOIN JSON_TABLE(#{ document }, '$[*]' COLUMNS (
           tag_id BIGINT PATH '$.tag_id' NULL ON EMPTY,
           external_tag_id BIGINT PATH '$.external_tag_id' NULL ON EMPTY)) tag_entry
 
@@ -112,6 +148,13 @@ class CountsAxes
       condition = @definition.changes.map do |field|
         "(changed.field_key = '#{ field }' AND #{ @population.changed_sql(field) })"
       end.join(' OR ')
+      unless HistoryAccess.admin?
+        visible = self.class.visibility_sql(@definition, 'changed_field')
+        marker = ApplicationRecord.connection.quote(MASKED_VALUE)
+        fields += " UNION ALL SELECT #{ marker } AS field_key"
+        condition = "((#{ visible }) AND (#{ condition })) OR " +
+            "(NOT (#{ visible }) AND changed.field_key = #{ marker })"
+      end
       result += " JOIN (#{ fields }) changed ON (#{ condition })"
     end
     result

backend/app/services/counts_condition.rb

@@ -82,14 +82,32 @@ class CountsCondition
 
   def apply(scope, entry)
     raise ArgumentError unless entry.is_a?(Hash)
+
     if entry['operator'] == 'axis_eq'
       raise ArgumentError unless (entry.keys - ['field', 'operator', 'grain', 'value']).empty?
       value = entry['value']
-      unless value.nil? || value.is_a?(String) || value.is_a?(Numeric) || [true, false].include?(value)
+      unless (value.nil? || value.is_a?(String) || value.is_a?(Numeric) ||
+          [true, false].include?(value))
         raise ArgumentError
       end
       raise ArgumentError if value.is_a?(String) && value.bytesize > 8192
 
+      if (!HistoryAccess.admin? && CountsAxes.private_field?(entry['field']) &&
+          (value == CountsAxes::MASKED_VALUE ||
+              (value == CountsAxes::MASKED_TEXT &&
+                  (@definition.fields[entry['field']] != :string ||
+                      ['tags', 'changed_field'].include?(entry['field'])))))
+        field = entry.fetch('field')
+        raise ArgumentError unless @definition.axes(@population.history).include?(field)
+        if entry.key?('grain')
+          unless (@definition.fields[field] == :datetime &&
+              CountsAxes::GRAINS.include?(entry['grain']))
+            raise ArgumentError
+          end
+        end
+        return scope.none
+      end
+      scope = @population.condition_scope(scope, entry.fetch('field'))
       return @population.axis_condition(scope, entry)
     end
     allowed = ['field', 'operator', 'value', 'end', 'blank', 'input', 'values']
@@ -111,6 +129,13 @@ class CountsCondition
 
     source, expression = source_for(field[:key])
     type = field[:type]
+    # Preserve typed input compatibility; display markers are never real typed values.
+    if (!HistoryAccess.admin? && CountsAxes.private_field?(field[:key]) &&
+        entry['value'] == CountsAxes::MASKED_TEXT && type != :string && !entry['blank'])
+      return scope.none unless entry['operator'] == 'ne'
+
+      return @population.condition_scope(scope, field[:key])
+    end
     blank = blank_sql(expression, type)
     if entry['blank']
       sql = if source && field[:collection]
@@ -119,6 +144,7 @@ class CountsCondition
               "NOT EXISTS (SELECT 1 FROM #{ source } WHERE NOT (#{ blank }))"
             else blank
             end
+      scope = @population.condition_scope(scope, field[:key])
       return scope.where(Arel.sql(sql))
     end
     if ['in', 'not_in', 'any', 'all', 'none'].include?(entry['operator'])
@@ -131,6 +157,7 @@ class CountsCondition
     validate_enum!(field[:key], parsed.first) if type == :enum
     operator = entry['operator']
     if type == :interval
+      scope = @population.condition_scope(scope, field[:key])
       return interval(scope, source, expression, parsed)
     end
     clauses = []
@@ -158,6 +185,7 @@ class CountsCondition
     elsif operator == 'ne'
       predicate = "(NOT (#{ predicate }) OR #{ blank })"
     end
+    scope = @population.condition_scope(scope, field[:key])
     scope.where(predicate, *binds)
   end
 
@@ -168,6 +196,13 @@ class CountsCondition
 
     values = entry['values']
     raise ArgumentError unless values.is_a?(Array) && values.length <= 100
+    if (!HistoryAccess.admin? && CountsAxes.private_field?(field[:key]) &&
+        values.include?(CountsAxes::MASKED_TEXT) &&
+        (field[:type] != :string || field[:set_type] == 'tag_reference'))
+      return scope.none if entry['operator'] == 'all'
+
+      values = values - [CountsAxes::MASKED_TEXT]
+    end
     raise ArgumentError if [entry['value'], entry['end']].any? { !_1.nil? && _1 != '' }
 
     parsed = values.map do |value|
@@ -191,7 +226,10 @@ class CountsCondition
 
     operator = entry['operator']
     if parsed.empty?
-      return ['in', 'any'].include?(operator) ? scope.none : scope
+      return scope.none if ['in', 'any'].include?(operator)
+      return scope if entry['values'].empty?
+
+      return @population.condition_scope(scope, field[:key])
     end
     source, expression = source_for(field[:key])
     if field[:set_type] == 'tag_reference'
@@ -212,6 +250,7 @@ class CountsCondition
       predicate = source ? "NOT #{ predicate }" :
           "(NOT #{ predicate } OR #{ blank_sql(expression, field[:type]) })"
     end
+    scope = @population.condition_scope(scope, field[:key])
     scope.where(predicate, *parsed)
   end
 

backend/app/services/counts_population.rb

@@ -70,6 +70,13 @@ class CountsPopulation
     @authorisation_flg ? HistoryAccess.sql(model, row) : 'TRUE'
   end
 
+  # Each predicate keeps its own visibility restriction, including OR branches.
+  def condition_scope(scope, field)
+    return scope if HistoryAccess.admin? || !CountsAxes.private_field?(field)
+
+    scope.where(Arel.sql(CountsAxes.visibility_sql(definition, field)))
+  end
+
   def axis_condition(scope, entry)
     raise CountsAxes::PrivateCondition if entry['value'] == CountsAxes::MASKED_VALUE
 
@@ -209,6 +216,7 @@ class CountsPopulation
   def apply_tags
     raise ArgumentError unless definition.resource == 'posts'
 
+    @scope = condition_scope(@scope, 'tags')
     if params['tag'].present?
       @scope = @scope.where(snapshot_membership(
           "#{ params.fetch('kind', 'internal') }:#{ params['tag'] }"))

backend/app/services/counts_table_export.rb

@@ -253,7 +253,7 @@ class CountsTableExport
   end
 
   def summary_value(value, index, page)
-    return '********' if value == CountsAxes::MASKED_VALUE
+    return CountsAxes::MASKED_TEXT if value == CountsAxes::MASKED_VALUE
 
     field = @query.axes.all.fetch(index).fetch('field')
     return @labels.fetch('bot', '') if field == 'user' && value.nil?

backend/app/services/counts_table_query.rb

@@ -220,19 +220,11 @@ class CountsTableQuery
 
   private
 
-  # Public timeline predicates may include hidden records. Private predicates must
+  # Private predicates require visibility independently of their operator.
-  # never become a count oracle, even when the selected axes themselves are public.
+  # Ordering/measure state must not select a server-only masked coordinate.
   def validate_summary_conditions!
     return if mode != 'summary' || HistoryAccess.admin?
 
-    fields = QueryState.records(@params, 'conditions') + QueryState.records(@params, 'drill')
-    private_fields = fields.any? { !CountsAxes::PUBLIC_FIELDS.include?(_1['field']) }
-    keys = ['tags', 'tag', 'kind', 'resource_id', 'user_id']
-    private_parameters = keys.any? do |key|
-      @params.any? { |name, value| (name == key || name.start_with?("#{ key }.")) && value != '' }
-    end
-    raise CountsAxes::PrivateCondition if private_fields || private_parameters
-
     ['column_order', 'measures'].each do |key|
       # Coordinates are compared only to already masked expressions, never raw
       # values. Public coordinates remain sortable; a guessed private ID cannot match.

backend/app/services/tag_description_operation.rb

@@ -37,6 +37,37 @@ class TagDescriptionOperation
     end
   end
 
+  def self.update_with_title! locale, tag:, body:, title:, actor:, base_revision_id: nil
+    return update!(locale, tag:, body:, updated_by_user: actor,
+                   base_revision_id:) if title.nil?
+
+    title = title.to_s.strip
+    tag_name = tag.tag_name(locale.language_code)
+    if title.blank? || title.include?(':') || !tag_name || tag_name.name.include?(':')
+      tag.errors.add(:title, :invalid)
+      raise ActiveRecord::RecordInvalid, tag
+    end
+
+    ApplicationRecord.transaction do
+      SharedResourceIdAllocator.lock_space!(Tag, 'tags')
+      tag.lock!
+      old_title = tag_name.name
+      if title != old_title
+        TagVersioning.ensure_snapshot!(tag, created_by_user: actor)
+      end
+
+      tag_name.update!(name: title) if title != old_title
+
+      update!(locale, tag:, body:, updated_by_user: actor,
+              base_revision_id:)
+
+      if title != old_title
+        tag.reload
+        TagVersionRecorder.record!(tag:, event_type: :update, created_by_user: actor)
+      end
+    end
+  end
+
   def self.record_version! description:, body:, user:
     creating = description.new_record?
     version_no = creating ? 1 : description.version_no + 1

backend/config/routes.rb

@@ -17,7 +17,11 @@ Rails.application.routes.draw do
   resources :locales, only: [:index]
   resources :sitemap_entries, only: [:index, :show], param: :resource
 
-  resources :tag_groups, only: [:index, :show, :create, :update]
+  resources :tag_groups, only: [:index, :show, :create, :update] do
+    collection do
+      get 'name/:name', action: :show_by_name
+    end
+  end
 
   resources :nico_tags, path: 'tags/nico', only: [:index, :show, :update]
 
@@ -28,6 +32,9 @@ Rails.application.routes.draw do
 
   resources :tags, only: [:index, :show] do
     collection do
+      get :descriptions, to: 'tag_descriptions#index'
+      post :descriptions, to: 'tag_descriptions#create'
+      get 'descriptions/:description_id', to: 'tag_descriptions#show_by_id'
       get :autocomplete
       get :'with-depth', action: :with_depth
       get :versions, to: 'tag_versions#index'

backend/db/seeds.rb

@@ -9,8 +9,21 @@
 #   end
 
 ApplicationRecord.transaction do
-  Language.find_or_create_by!(code: 'ain') { _1.name = 'ain' }
+  Language.find_or_create_by!(code: 'ja') { _1.name = '日本語' }
-  Script.find_or_create_by!(code: 'Kana') { _1.name = 'Kana' }
+  Script.find_or_create_by!(code: 'Jpan') { _1.name = '漢字、仮名文字およびラテン文字' }
+  Region.find_or_create_by!(code: 392) do
+    _1.alpha_code = 'JP'
+    _1.name = '日本国'
+  end
+  Locale.find_or_create_by!(code: 'ja') do
+    _1.language_code = 'ja'
+    _1.script_code = 'Jpan'
+    _1.region_code = 392
+    _1.name = '日本語'
+  end
+
+  Language.find_or_create_by!(code: 'ain') { _1.name = 'ヤウンモシルン　アイヌ　イタㇰ' }
+  Script.find_or_create_by!(code: 'Kana') { _1.name = 'カナモジ　オヨビ　ラテンモジ' }
 end
 
 post_url_sanitisation_rules = [

backend/spec/requests/counts_masked_search_spec.rb

@@ -0,0 +1,196 @@
+require 'rails_helper'
+
+RSpec.describe 'Counts masked search', type: :request do
+  let!(:tag) { create(:tag, primary_name: '秘密のタグ') }
+  let(:actor) { create(:user, :member) }
+  let(:admin) { create(:user, :admin) }
+  let(:base) do
+    { 'resource' => 'tags', 'definition' => 'history', 'mode' => 'summary',
+      'locale' => 'ja', 'execution_at' => '2025-01-01T00:00:00Z',
+      'timezone' => 'UTC', 'rows' => '', 'cols' => '', 'sort' => '' }
+  end
+
+  before do
+    [1, 2].each do |number|
+      TagVersion.create!(tag:, version_no: number,
+          event_type: number == 1 ? 'create' : 'discard', name: '秘密のタグ',
+          category: 'general', aliases: '秘密の別名', parent_tag_ids: '',
+          names: { ja: { name: '秘密のタグ', script_code: 'Jpan', auto_generated: false,
+                        aliases: [{ name: '秘密の別名', script_code: 'Jpan' }] } },
+          created_by_user: actor, created_at: Time.utc(2023, number))
+    end
+  end
+
+  def query(extra = {})
+    get '/counts/query', params: base.merge(extra)
+    expect(response).to have_http_status(:ok), extra.inspect
+    response.parsed_body
+  end
+
+  def predicate(field, operator, value, index = 0)
+    prefix = "conditions.#{ index }"
+    result = { 'conditions' => '', "#{ prefix }.field" => field,
+               "#{ prefix }.operator" => operator }
+    if ['in', 'any', 'all', 'none', 'not_in'].include?(operator)
+      result.merge!("#{ prefix }.values" => '1', 'condition_values' => '',
+          "condition_values.#{ index }.condition" => index.to_s,
+          "condition_values.#{ index }.value_type" => 'string',
+          "condition_values.#{ index }.value" => value)
+    else
+      result["#{ prefix }.value"] = value
+    end
+    result
+  end
+
+  it 'rejects every name and alias predicate on private history' do
+    ['name', 'name_ja', 'names.name', 'aliases.name', 'names.aliases.name'].each do |field|
+      secret = field.include?('aliases') ? '秘密の別名' : '秘密のタグ'
+      multiple = !['name', 'name_ja'].include?(field)
+      operators = multiple ? ['any', 'all', 'none'] : ['in', 'not_in']
+      ['eq', 'ne', 'like', *operators].each do |operator|
+        [secret, '********', '%', ''].each do |value|
+          expected = (value == '' && ['eq', 'ne', 'like'].include?(operator)) ? 2 : 0
+          expect(query(predicate(field, operator, value))['count']).to eq(expected)
+        end
+      end
+      blank = predicate(field, 'eq', '').merge('conditions.0.blank' => '1')
+      expect(query(blank)['count']).to eq(0)
+    end
+  end
+
+  it 'ignores missing and empty scalar values unless blank is checked' do
+    ['name', 'name_ja', 'names.name', 'aliases.name'].each do |field|
+      ['eq', 'ne', 'like'].each do |operator|
+        condition = predicate(field, operator, '')
+        [condition, condition.except('conditions.0.value')].each do |empty|
+          expect(query(empty)['count']).to eq(2)
+          expect(query(empty.merge('conditions.0.blank' => '0'))['count']).to eq(2)
+          expect(query(empty.merge('conditions.0.blank' => '1'))['count']).to eq(0)
+        end
+      end
+    end
+  end
+
+  it 'keeps details totals unchanged for inactive private predicates' do
+    settings = predicate('name', 'ne', '').merge('mode' => 'details')
+    result = query(settings)
+    expect(result['count']).to eq(0)
+    expect(result['versions']).to be_empty
+    expect(result['output_count']).to eq(2)
+    active = query(settings.merge('conditions.0.blank' => '1'))
+    expect(active['output_count']).to eq(0)
+  end
+
+  it 'ignores missing sets but preserves explicit empty set semantics' do
+    { 'name' => ['in', 'not_in'], 'aliases.name' => ['any', 'all', 'none'] }.each do
+        |field, operators|
+      operators.each do |operator|
+        condition = { 'conditions' => '', 'conditions.0.field' => field,
+                      'conditions.0.operator' => operator }
+        expect(query(condition)['count']).to eq(2)
+        empty = condition.merge('conditions.0.values' => '1', 'condition_values' => '')
+        expected = ['in', 'any'].include?(operator) ? 0 : 2
+        expect(query(empty)['count']).to eq(expected)
+        expect(query(condition.merge('conditions.0.blank' => '1'))['count']).to eq(0)
+        # An explicit empty string element is a real value, not an unspecified set.
+        expect(query(predicate(field, operator, ''))['count']).to eq(0)
+      end
+    end
+  end
+
+  it 'ignores empty private predicates regardless of their position' do
+    first = predicate('name', 'ne', '')
+        .merge(predicate('resource_id', 'eq', tag.id.to_s, 1))
+    last = predicate('resource_id', 'eq', tag.id.to_s)
+        .merge(predicate('aliases.name', 'like', '', 1))
+    expect(query(first)['count']).to eq(2)
+    expect(query(last)['count']).to eq(2)
+    active = predicate('name', 'ne', 'unrelated')
+        .merge(predicate('aliases.name', 'like', '', 1))
+    expect(query(active)['count']).to eq(0)
+  end
+
+  it 'searches public literal markers and treats axis predicates as explicit' do
+    public_tag = create(:tag, primary_name: '********')
+    TagVersion.create!(tag: public_tag, version_no: 1, event_type: 'create',
+        name: '********', category: 'general', aliases: '', parent_tag_ids: '',
+        names: { ja: { name: '********', script_code: 'Jpan', auto_generated: false,
+                      aliases: [] } }, created_at: Time.utc(2023))
+    expect(query['count']).to eq(3)
+    ['eq', 'ne', 'like', 'in', 'not_in'].each do |operator|
+      expected = ['ne', 'not_in'].include?(operator) ? 0 : 1
+      expect(query(predicate('name', operator, '********'))['count']).to eq(expected)
+    end
+    blank = predicate('aliases.name', 'eq', '').merge('conditions.0.blank' => '1')
+    expect(query(blank)['count']).to eq(1)
+    ['********', '', nil].each do |value|
+      condition = { 'conditions' => '', 'conditions.0.field' => 'name',
+                    'conditions.0.operator' => 'axis_eq',
+                    'conditions.0.value_type' => value.nil? ? 'null' : 'string' }
+      condition['conditions.0.value'] = value unless value.nil?
+      expected = value == '********' ? 1 : 0
+      expect(query(condition)['count']).to eq(expected)
+      drill = { 'drill' => '', 'drill.0.field' => 'name',
+                'drill.0.value_type' => value.nil? ? 'null' : 'string' }
+      drill['drill.0.value'] = value unless value.nil?
+      expect(query(drill)['count']).to eq(expected)
+    end
+  end
+
+  it 'keeps public identity and timeline predicates searchable' do
+    expect(query['count']).to eq(2)
+    values = { 'resource_id' => tag.id.to_s, 'version_no' => '2',
+               'event_type' => 'discard', 'user' => actor.id.to_s,
+               'created_at' => '2023-02-01T00:00:00Z' }
+    values.each do |field, value|
+      expected = ['resource_id', 'user'].include?(field) ? 2 : 1
+      expect(query(predicate(field, 'eq', value))['count']).to eq(expected)
+    end
+    condition = predicate('name', 'ne', '秘密のタグ')
+        .merge(predicate('event_type', 'eq', 'discard', 1))
+    expect(query(condition)['count']).to eq(0)
+    expect(query(predicate('category', 'eq', '********'))['count']).to eq(0)
+    expect(query(predicate('category', 'eq', 'general'))['count']).to eq(0)
+  end
+
+  it 'keeps public predicates available after combining multiple conditions' do
+    condition = predicate('resource_id', 'eq', tag.id.to_s)
+        .merge(predicate('event_type', 'eq', 'discard', 1))
+    expect(query(condition)['count']).to eq(1)
+    condition.merge!(predicate('name', 'ne', 'unrelated', 2))
+    expect(query(condition)['count']).to eq(0)
+  end
+
+  it 'keeps real name searches for administrators and excludes private details' do
+    condition = predicate('name', 'eq', '秘密のタグ')
+    details = query(condition.merge('mode' => 'details'))
+    expect(details['versions']).to be_empty
+    expect(details['output_count']).to eq(0)
+    masked = query(predicate('name', 'eq', '********').merge('mode' => 'details'))
+    expect(masked['versions']).to be_empty
+    expect(masked['output_count']).to eq(0)
+    sign_in_as(admin)
+    expect(query(condition)['count']).to eq(2)
+    expect(query(condition.merge('mode' => 'details'))['versions'].length).to eq(2)
+  end
+
+  it 'rejects private names reached through a post tag snapshot' do
+    post = create(:post)
+    PostVersion.create!(post:, version_no: 1, event_type: 'create', title: 'post',
+        url: post.url, tags: '', parent_post_ids: '',
+        tags_json: [{ tag_id: tag.id, version_no: 1, name: '秘密のタグ',
+                     category: 'general', sections: [] }],
+        created_at: Time.utc(2024))
+    ['tags.name', 'tags.names.name', 'tags.name_ja'].each do |field|
+      ['eq', 'ne', 'like', 'any', 'all', 'none'].each do |operator|
+        ['秘密のタグ', '********', '%'].each do |value|
+          settings = predicate(field, operator, value).merge('resource' => 'posts')
+          expect(query(settings)['count']).to eq(0)
+        end
+      end
+      blank = predicate(field, 'eq', '').merge('resource' => 'posts',
+          'conditions.0.blank' => '1')
+      expect(query(blank)['count']).to eq(0)
+    end
+  end
+end

backend/spec/requests/counts_table_spec.rb

@@ -354,15 +354,25 @@ RSpec.describe 'Counts table API', type: :request do
     expect(result['cells'].sum { _1['count'] }).to eq(4)
     expect(response.body).not_to include('hidden title')
     masked = query(mode: 'summary', rows: 'resource_id', cols: '')
-    expect(masked['cells'].map { _1['values'] }).to eq([[CountsAxes::MASKED_VALUE]])
+    expect(masked['cells'].map { _1['values'] }).to eq([[record.id]])
     expect(masked['cells'].first['count']).to eq(4)
     expect(query['versions']).to be_empty
   end
 
-  it 'rejects private summary predicates instead of exposing a count oracle' do
+  it 'allows public identity predicates without exposing private snapshot fields' do
-    get '/counts/query', params: base.merge(mode: 'summary', resource_id: record.id.to_s)
+    PostVersion.create!(post: record, version_no: 4, event_type: 'discard',
-    expect(response).to have_http_status(:forbidden)
+        url: record.url, title: 'hidden title', tags: '', tags_json: [],
-    expect(json).to eq('error' => 'private_condition')
+        parent_post_ids: '', created_at: Time.utc(2024, 3))
+
+    get '/counts/query', params: base.merge(mode: 'summary',
+        resource_id: record.id.to_s, rows: 'resource_id', cols: 'title')
+
+    expect(response).to have_http_status(:ok)
+    expect(json['count']).to eq(4)
+    expect(json['cells'].sum { _1['count'] }).to eq(4)
+    expect(json['cells'].map { _1['values'].last })
+        .to include(CountsAxes::MASKED_VALUE)
+    expect(response.body).not_to include('hidden title')
   end
 
   it 'reports the combined axis limit without replacing it with a generic 400' do

backend/spec/services/counts_pivot_security_spec.rb

@@ -69,27 +69,29 @@ RSpec.describe 'Counts masked pivot contracts' do
     end
   end
 
-  it 'preserves five tag occurrences after merging private tags and across pages' do
+  it 'counts one opaque collection per private version across pages' do
     [nil, guest, member, admin].each do |user|
       page = result(user)
-      expect(grand(page)).to eq(5)
+      expected = user == admin ? 5 : 6
-      expect(page[:cells].sum { _1[:count] }).to eq(5)
+      expect(grand(page)).to eq(expected)
+      expect(page[:cells].sum { _1[:count] }).to eq(expected)
       expect(page).not_to have_key(:excluded_count)
       paged = result(user, 'limit' => '1')
-      expect(grand(paged)).to eq(5)
+      expect(grand(paged)).to eq(expected)
       expect(result(user, 'limit' => '1', 'page' => '2')[:group_count])
           .to eq(page[:group_count])
     end
     public_page = result(nil)
     hidden = public_page[:cells].select { _1[:values].first == CountsAxes::MASKED_VALUE }
-    expect(hidden.sum { _1[:count] }).to eq(3)
+    expect(hidden.sum { _1[:count] }).to eq(4)
     expect(public_page[:axis_labels]['a0']).not_to have_key("internal:#{ tags.first.id }")
     expect(public_page.to_json).not_to include('hidden-title', 'private-discard')
   end
 
   it 'retains distinct membership when tags are not a row axis' do
     [nil, admin].each do |user|
-      expect(grand(result(user, 'rows' => 'event_type', 'cols' => 'tags'))).to eq(3)
+      expect(grand(result(user, 'rows' => 'event_type', 'cols' => 'tags')))
+          .to eq(user == admin ? 3 : 5)
       expect(result(user, 'rows' => '', 'cols' => '')[:cells].sole[:count]).to eq(5)
       details = result(user, 'mode' => 'details', 'rows' => '', 'cols' => '')
       expect(details[:count]).to eq(user == admin ? 5 : 1)
@@ -121,14 +123,13 @@ RSpec.describe 'Counts masked pivot contracts' do
   it 'counts distinct changed records when tags are not additive row tuples' do
     [nil, admin].each do |user|
       page = result(user, 'rows' => 'changed_field', 'cols' => 'event_type')
-      expect(grand(page)).to eq(2)
+      expect(grand(page)).to eq(user == admin ? 2 : 4)
       if user.nil?
         expect(page[:cells].map { _1[:values].first }.uniq).to eq([CountsAxes::MASKED_VALUE])
       end
-      # Changed discard snapshots have no tags: no full cell contributes here.
+      # Private empty collections contribute the same opaque tuple as populated ones.
-      empty = result(user, 'rows' => 'changed_field', 'cols' => 'tags')
+      combined = result(user, 'rows' => 'changed_field', 'cols' => 'tags')
-      expect(empty[:cells]).to be_empty
+      expect(grand(combined)).to eq(user == admin ? 0 : 4)
-      expect(grand(empty)).to eq(0)
     end
   end
 
@@ -142,7 +143,7 @@ RSpec.describe 'Counts masked pivot contracts' do
     expect(page[:row_headers]).to include(hash_including(values: [nil], kind: 'data'))
   end
 
-  it 'sorts public numeric values numerically alongside a masked group' do
+  it 'sorts public version numbers numerically including formerly hidden records' do
     post = PostVersion.order(:id).last.post
     [2, 10].each do |number|
       PostVersion.create!(post:, version_no: number, event_type: 'update',
@@ -151,27 +152,196 @@ RSpec.describe 'Counts masked pivot contracts' do
     end
     page = result(nil, 'rows' => 'version_no', 'cols' => '')
     values = page[:row_headers].select { _1[:kind] == 'data' }.map { _1[:values].first }
-    expect(values.reject { _1 == CountsAxes::MASKED_VALUE }.map(&:to_i)).to eq([1, 2, 10])
+    expect(values.map(&:to_i)).to eq([1, 2, 10])
-    expect(values.last).to eq(CountsAxes::MASKED_VALUE)
   end
 
-  it 'rejects private predicates and supplied measure coordinates before SQL labels escape' do
+  it 'keeps public identity predicates and excludes private attributes' do
-    probes = [{ 'resource_id' => PostVersion.first.post_id.to_s },
+    hidden_id = PostVersion.first.post_id.to_s
-        { 'tags' => 'A' },
+    base = { 'rows' => '', 'cols' => '' }
-        { 'conditions' => '', 'conditions.0.field' => 'title', 'conditions.0.operator' => 'eq',
+    condition = lambda do |field, operator, value|
-          'conditions.0.value' => 'hidden-title-0' },
+      { 'conditions' => '', 'conditions.0.field' => field,
-        { 'drill' => '', 'drill.0.field' => 'tags', 'drill.0.value_type' => 'string',
+        'conditions.0.operator' => operator, 'conditions.0.value' => value }
-          'drill.0.value' => "internal:#{ tags.first.id }" },
+    end
+
+    expect(result(nil, base.merge('resource_id' => hidden_id))[:cells].sole[:count]).to eq(2)
+    expect(result(nil, base.merge(condition.call('version_no', 'eq', '2')))[:cells]
+        .sole[:count]).to eq(2)
+    expect(result(nil, base.merge(condition.call('user', 'eq', member.id.to_s)))[:cells]
+        .sole[:count]).to eq(5)
+    expect(result(nil, base.merge(condition.call('title', 'eq', 'hidden-title-0')))[:cells]
+        .sole[:count]).to eq(0)
+    expect(result(nil, base.merge(condition.call('title', 'ne', 'hidden-title-0')))[:cells]
+        .sole[:count]).to eq(1)
+    expect(result(nil, base.merge(condition.call('title', 'eq', '********')))[:cells]
+        .sole[:count]).to eq(0)
+    expect(result(nil, base.merge(condition.call('video_ms', 'eq', '********')))[:cells]
+        .sole[:count]).to eq(0)
+    expect(result(nil, base.merge(condition.call('title', 'like', '%title%')))[:cells]
+        .sole[:count]).to eq(1)
+    expect(result(nil, base.merge(condition.call('title', 'like', '%')))[:cells]
+        .sole[:count]).to eq(1)
+    expect(result(nil, base.merge('tags' => 'C'))[:cells].sole[:count]).to eq(1)
+    expect(result(nil, base.merge('tags' => 'not:C'))[:cells].sole[:count]).to eq(0)
+  end
+
+  it 'retains public OR branches while rejecting private predicates on hidden rows' do
+    HistoryAccess.set(user: nil) do
+      population = CountsPopulation.new(params.merge('rows' => '', 'cols' => ''),
+          authorisation_flg: false)
+      condition = CountsCondition.new(population)
+      public_scope = condition.apply(population.scope,
+          { 'field' => 'event_type', 'operator' => 'eq', 'value' => 'discard' })
+      private_scope = condition.apply(population.scope,
+          { 'field' => 'title', 'operator' => 'ne', 'value' => 'unrelated' })
+      masked_scope = condition.apply(population.scope,
+          { 'field' => 'title', 'operator' => 'eq', 'value' => '********' })
+      expect(public_scope.except(:select).count).to eq(2)
+      expect(public_scope.or(private_scope).except(:select).count).to eq(3)
+      expect(private_scope.or(public_scope).except(:select).count).to eq(3)
+      expect(public_scope.or(masked_scope).except(:select).count).to eq(2)
+      expect(public_scope.merge(private_scope).except(:select).count).to eq(0)
+    end
+  end
+
+  it 'excludes private collections from positive, negative, AND and OR tag searches' do
+    settings = { 'rows' => '', 'cols' => '' }
+    { 'C' => 1, 'not:C' => 0, 'not:unknown' => 1, '********' => 0,
+      'not:********' => 1, 'not:C C' => 0, 'not:C type:or C' => 1 }.each do |value, count|
+      expect(result(nil, settings.merge('tags' => value))[:cells].sole[:count]).to eq(count)
+    end
+  end
+
+  it 'ignores empty numeric and interval bounds without restricting private history' do
+    settings = { 'rows' => '', 'cols' => '', 'conditions' => '' }
+    { 'video_ms' => ['eq', 'ne', 'gt', 'ge', 'lt', 'le', 'range'],
+      'tags.sections' => ['range'] }.each do |field, operators|
+      operators.each do |operator|
+        condition = settings.merge('conditions.0.field' => field,
+            'conditions.0.operator' => operator)
+        empty = condition.merge('conditions.0.value' => '')
+        expect(result(nil, condition)[:cells].sole[:count]).to eq(5)
+        expect(result(nil, empty)[:cells].sole[:count]).to eq(5)
+        expect(result(nil, empty.merge('conditions.0.blank' => '0'))[:cells]
+            .sole[:count]).to eq(5)
+        if operator == 'range'
+          empty['conditions.0.end'] = ''
+          expect(result(nil, empty)[:cells].sole[:count]).to eq(5)
+          ['conditions.0.value', 'conditions.0.end'].each do |key|
+            active = empty.merge(key => '100')
+            expect(result(nil, active)[:cells].sole[:count]).to eq(0)
+          end
+        end
+      end
+    end
+  end
+
+  it 'keeps typed marker sets active after incompatible marker values are removed' do
+    settings = { 'rows' => '', 'cols' => '', 'conditions' => '',
+                 'conditions.0.field' => 'video_ms', 'conditions.0.values' => '1',
+                 'condition_values' => '', 'condition_values.0.condition' => '0',
+                 'condition_values.0.value_type' => 'string',
+                 'condition_values.0.value' => '********' }
+    ['in', 'not_in'].each do |operator|
+      expected = operator == 'in' ? 0 : 1
+      condition = settings.merge('conditions.0.operator' => operator)
+      expect(result(nil, condition)[:cells].sole[:count]).to eq(expected)
+    end
+  end
+
+  it 'restricts active numeric comparisons and preserves empty selection semantics' do
+    settings = { 'rows' => '', 'cols' => '', 'conditions' => '',
+                 'conditions.0.field' => 'video_ms' }
+    ['eq', 'ne', 'gt', 'ge', 'lt', 'le', 'range'].each do |operator|
+      condition = settings.merge('conditions.0.operator' => operator,
+          'conditions.0.value' => '0')
+      condition['conditions.0.end'] = '100' if operator == 'range'
+      # The one public row is NULL; private NULLs and real values never match.
+      expected = operator == 'ne' ? 1 : 0
+      expect(result(nil, condition)[:cells].sole[:count]).to eq(expected)
+    end
+    ['in', 'not_in'].each do |operator|
+      condition = settings.merge('conditions.0.operator' => operator,
+          'conditions.0.values' => '1', 'condition_values' => '')
+      expected = operator == 'not_in' ? 5 : 0
+      expect(result(nil, condition)[:cells].sole[:count]).to eq(expected)
+    end
+    blank = settings.merge('conditions.0.operator' => 'eq', 'conditions.0.blank' => '1')
+    expect(result(nil, blank)[:cells].sole[:count]).to eq(1)
+  end
+
+  it 'preserves empty tag sets and restricts active blank collection predicates' do
+    settings = { 'rows' => '', 'cols' => '', 'conditions' => '',
+                 'conditions.0.field' => 'tags' }
+    ['any', 'all', 'none'].each do |operator|
+      condition = settings.merge('conditions.0.operator' => operator,
+          'conditions.0.values' => '1', 'condition_values' => '')
+      expected = operator == 'any' ? 0 : 5
+      expect(result(nil, condition)[:cells].sole[:count]).to eq(expected)
+    end
+    blank = settings.merge('conditions.0.operator' => 'eq', 'conditions.0.blank' => '1')
+    expect(result(nil, blank)[:cells].sole[:count]).to eq(0)
+  end
+
+  it 'rejects server-only coordinates in column order' do
+    probes = [
         { 'cols' => 'tags', 'column_order' => '', 'column_order.0.value_type' => 'string',
           'column_order.0.value' => CountsAxes::MASKED_VALUE }]
     HistoryAccess.set(user: nil) do
       probes.each do |probe|
-        expect { CountsTableQuery.new(params.merge(probe)) }
+        expect { CountsTableQuery.new(params.merge(probe)).call }
             .to raise_error(CountsAxes::PrivateCondition)
       end
     end
   end
 
+
+  it 'keeps private collection and change counts independent of stored elements' do
+    settings = [
+        { 'rows' => 'tags', 'cols' => 'changed_field' },
+        { 'rows' => 'changed_field tags', 'cols' => '' }]
+    original = settings.map { result(nil, _1) }
+    snapshot = tags.map do |tag|
+      { tag_id: tag.id, version_no: 1, sections: [] }
+    end
+    hidden_posts = PostVersion.where(event_type: 'discard').pluck(:post_id)
+    PostVersion.where(post_id: hidden_posts).update_all(
+        title: 'same hidden value', tags_json: snapshot)
+    expect(settings.map { result(nil, _1) }).to eq(original)
+  end
+
+  it 'excludes private tag and change coordinates from drill conditions' do
+    ['tags', 'changed_field'].each do |field|
+      settings = { 'rows' => field, 'cols' => '' }
+      page = result(nil, settings)
+      cell = page[:cells].find { _1[:values] == [CountsAxes::MASKED_VALUE] }
+      expect(cell[:count]).to eq(4)
+      [CountsAxes::MASKED_VALUE, CountsAxes::MASKED_TEXT].each do |value|
+        drill = { 'drill' => '', 'drill.0.field' => field,
+                  'drill.0.value_type' => 'string', 'drill.0.value' => value }
+        expect(result(nil, settings.merge(drill))[:cells]).to be_empty
+        details = result(nil, settings.merge(drill).merge('mode' => 'details'))
+        expect(details[:versions]).to be_empty
+        condition = { 'conditions' => '', 'conditions.0.field' => field,
+                      'conditions.0.operator' => 'axis_eq',
+                      'conditions.0.value_type' => 'string', 'conditions.0.value' => value }
+        expect(result(nil, settings.merge(condition))[:cells]).to be_empty
+      end
+    end
+  end
+
+  it 'rejects real private tag and change coordinates for non-admin users' do
+    [nil, guest, member].each do |user|
+      { 'tags' => "internal:#{ tags.first.id }", 'changed_field' => 'title' }.each do
+          |field, value|
+        settings = { 'rows' => '', 'cols' => '', 'drill' => '',
+                     'drill.0.field' => field, 'drill.0.value_type' => 'string',
+                     'drill.0.value' => value }
+        expect(result(user, settings)[:cells].sole[:count]).to eq(0)
+        expect(result(admin, settings)[:cells].sole[:count]).to be > 0
+      end
+    end
+  end
+
   it 'keeps public column sorting usable while guessed private coordinates match nothing' do
     first = result(nil, 'rows' => 'event_type', 'cols' => 'tags')
     probe = result(nil, 'rows' => 'event_type', 'cols' => 'tags',
@@ -187,7 +357,7 @@ RSpec.describe 'Counts masked pivot contracts' do
     HistoryAccess.set(user: nil) do
       payload = params.merge('format' => 'json')
       json = JSON.parse(CountsTableExport.new(payload).body.to_a.join)
-      expect(json['data'].sum { _1['kind'] == 'data' ? _1['count'] : 0 }).to eq(5)
+      expect(json['data'].sum { _1['kind'] == 'data' ? _1['count'] : 0 }).to eq(6)
       expect(json.to_json).not_to include('hidden-title', 'private-discard')
       csv = CountsTableExport.new(payload.merge('format' => 'csv')).body.to_a.join
       expect(csv).to include('********')

frontend/src/App.tsx

@@ -166,7 +166,13 @@ export const pageRoutes = (
 	    robots: 'noindex', authentication: 'user' } },
 	{ path: ':id', element: <MaterialDetailPage/>,
 	  handle: { preload: MaterialDetailPage.preload, sitemap: ['materials'] } }] },
-    { path: 'wiki', element: <WikiSearchPage/>,
+    { path: 'wiki', element: <LocaleRedirect to="/tag-descriptions"/>,
+      handle: { redirectTo: '/tag-descriptions' } },
+    { path: 'tag-descriptions',
+      element: <WikiSearchPage key="tag_description" resourceType="tag_description"/>,
+      handle: { preload: WikiSearchPage.preload, sitemap: ['static'] } },
+    { path: 'tag-groups',
+      element: <WikiSearchPage key="tag_group" resourceType="tag_group"/>,
       handle: { preload: WikiSearchPage.preload, sitemap: ['static'] } },
     { path: 'wiki/:title', element: <WikiDetailPage/>,
       handle: { preload: WikiDetailPage.preload, switchLocale: switchWikiLocale,

frontend/src/components/TagSearch.test.tsx

@@ -0,0 +1,120 @@
+import { fireEvent, screen } from '@testing-library/react'
+import userEvent from '@testing-library/user-event'
+import { useLocation } from 'react-router-dom'
+import { beforeEach, describe, expect, it, vi } from 'vitest'
+
+import TagSearch from '@/components/TagSearch'
+import * as api from '@/lib/api'
+import { buildTag } from '@/test/factories'
+import { renderWithProviders } from '@/test/render'
+
+
+const LocationOutput = () => {
+  const location = useLocation ()
+  return <output data-testid="location">{location.pathname}{location.search}</output>
+}
+
+
+const renderSearch = () => renderWithProviders (
+    <>
+      <TagSearch/>
+      <LocationOutput/>
+    </>, { route: '/ja/posts?page=3' })
+
+
+describe ('TagSearch', () => {
+  beforeEach (() => {
+    vi.spyOn (api, 'apiGet').mockResolvedValue ([])
+  })
+
+  it ('searches through native submission without an Enter key event', () => {
+    renderSearch ()
+    const input = screen.getByRole<HTMLInputElement> ('textbox')
+    fireEvent.change (input, { target: { value: '虹夏 not:TEST type:or' } })
+
+    expect (input.form).toBeInstanceOf (HTMLFormElement)
+    fireEvent.submit (input.form!)
+
+    const query = new URLSearchParams ({ tags: '虹夏 not:test', match: 'any' })
+    expect (screen.getByTestId ('location')).toHaveTextContent (
+	`/ja/posts?${ query }`)
+    expect (input).toHaveValue ('虹夏 not:test type:or')
+  })
+
+  it ('requests a search action from the software keyboard', () => {
+    renderSearch ()
+
+    expect (screen.getByRole ('textbox')).toHaveAttribute ('enterkeyhint', 'search')
+  })
+
+  it ('searches through the form when Enter is pressed', async () => {
+    const user = userEvent.setup ()
+    renderSearch ()
+
+    await user.type (screen.getByRole ('textbox'), '虹夏{Enter}')
+
+    const query = new URLSearchParams ({ tags: '虹夏', match: 'all' })
+    expect (screen.getByTestId ('location')).toHaveTextContent (
+	`/ja/posts?${ query }`)
+  })
+
+  it.each ([
+      { label: 'composition flag', composing: true, keyCode: 13 },
+      { label: 'legacy IME code', composing: false, keyCode: 229 }]) (
+      'cancels confirmation Enter with $label', ({ composing, keyCode }) => {
+    renderSearch ()
+    const input = screen.getByRole ('textbox')
+    fireEvent.change (input, { target: { value: '虹夏' } })
+    const uncancelled = fireEvent.keyDown (input, {
+	key: 'Enter', isComposing: composing, keyCode })
+
+    expect (uncancelled).toBe (false)
+    expect (screen.getByTestId ('location')).toHaveTextContent ('/ja/posts?page=3')
+    expect (input).toHaveValue ('虹夏')
+  })
+
+  it ('cancels Enter throughout composition even without keyboard IME flags', () => {
+    renderSearch ()
+    const input = screen.getByRole ('textbox')
+    fireEvent.compositionStart (input)
+    fireEvent.change (input, { target: { value: '虹夏' } })
+    const uncancelled = fireEvent.keyDown (input, {
+	key: 'Enter', isComposing: false, keyCode: 13 })
+
+    expect (uncancelled).toBe (false)
+    expect (screen.getByTestId ('location')).toHaveTextContent ('/ja/posts?page=3')
+    expect (input).toHaveValue ('虹夏')
+  })
+
+  it ('blocks direct submission during composition and allows it after confirmation', () => {
+    renderSearch ()
+    const input = screen.getByRole<HTMLInputElement> ('textbox')
+    fireEvent.compositionStart (input)
+    fireEvent.change (input, { target: { value: '虹夏' } })
+    fireEvent.submit (input.form!)
+
+    expect (screen.getByTestId ('location')).toHaveTextContent ('/ja/posts?page=3')
+    expect (input).toHaveValue ('虹夏')
+
+    fireEvent.compositionEnd (input)
+    fireEvent.submit (input.form!)
+
+    const query = new URLSearchParams ({ tags: '虹夏', match: 'all' })
+    expect (screen.getByTestId ('location')).toHaveTextContent (
+	`/ja/posts?${ query }`)
+  })
+
+  it ('selects the active suggestion without submitting the form', async () => {
+    vi.mocked (api.apiGet).mockResolvedValue ([buildTag ({ name: '虹夏' })])
+    const user = userEvent.setup ()
+    renderSearch ()
+
+    await user.type (screen.getByRole ('textbox'), '虹')
+    await screen.findByText ('虹夏')
+    await user.keyboard ('{ArrowDown}{Enter}')
+
+    expect (screen.getByRole ('textbox')).toHaveValue ('虹夏 ')
+    expect (screen.getByTestId ('location')).toHaveTextContent ('/ja/posts?page=3')
+    expect (screen.queryByText ('虹夏')).not.toBeInTheDocument ()
+  })
+})

frontend/src/components/TagSearch.tsx

@@ -1,6 +1,6 @@
 // TODO: タグ入力系すべてに同様の処理あるため共通化する．
 
-import { useEffect, useState } from 'react'
+import { useEffect, useRef, useState } from 'react'
 import { useLocation } from 'react-router-dom'
 
 import { useLocale, useLocaleNavigate } from '@/lib/useLocale'
@@ -10,7 +10,7 @@ import { inputClass } from '@/lib/utils'
 
 import TagSearchBox from './TagSearchBox'
 
-import type { ChangeEvent, FC, KeyboardEvent } from 'react'
+import type { ChangeEvent, FC, FormEvent, KeyboardEvent } from 'react'
 
 import type { Tag } from '@/types'
 
@@ -20,6 +20,7 @@ const TagSearch: FC = () => {
   const locale = useLocale ()
   const location = useLocation ()
   const navigate = useLocaleNavigate ()
+  const compositionFlgRef = useRef (false)
 
   const [activeIndex, setActiveIndex] = useState (-1)
   const [search, setSearch] = useState ('')
@@ -74,7 +75,34 @@ const TagSearch: FC = () => {
     setSuggestionsVsbl (false)
   }, [locale])
 
+  const handleSubmit = (ev: FormEvent<HTMLFormElement>) => {
+    ev.preventDefault ()
+    if (compositionFlgRef.current)
+      return
+
+    const parts = search.split (' ')
+    const match =
+	parts.map (t => t.toLowerCase ()).includes ('type:or') ? 'any' : 'all'
+    navigate (`/posts?${
+	(new URLSearchParams ({
+	    tags: parts.map (t => t.toLowerCase ())
+		       .filter (t => t !== 'type:or')
+		       .join (' '),
+	    match })).toString () }`)
+    setSuggestionsVsbl (false)
+    setRequest ({ query: '' })
+  }
+
   const handleKeyDown = (ev: KeyboardEvent<HTMLInputElement>) => {
+    if (compositionFlgRef.current
+	|| ev.nativeEvent.isComposing
+	|| ev.nativeEvent.keyCode === 229)
+    {
+      if (ev.key === 'Enter')
+	ev.preventDefault ()
+      return
+    }
+
     switch (ev.key)
     {
     case 'ArrowDown':
@@ -90,13 +118,12 @@ const TagSearch: FC = () => {
       break
 
     case 'Enter':
-      if (activeIndex < 0)
-	break
-      ev.preventDefault ()
       {
-	const selected = suggestions[activeIndex]
+	const selected = suggestionsVsbl ? suggestions[activeIndex] : null
-	if (selected)
+	if (selected == null)
-	  handleTagSelect (selected)
+	  break
+	ev.preventDefault ()
+	handleTagSelect (selected)
       }
       break
 
@@ -105,20 +132,6 @@ const TagSearch: FC = () => {
       setSuggestionsVsbl (false)
       break
     }
-    if (ev.key === 'Enter' && (!(suggestionsVsbl) || activeIndex < 0))
-      {
-	const parts = search.split (' ')
-	const match = parts.map (t => t.toLowerCase ()).includes ('type:or') ? 'any' : 'all'
-	navigate (`/posts?${
-	    (new URLSearchParams ({
-		tags: parts.map (t => t.toLowerCase ())
-			   .filter (t => t !== 'type:or')
-			   .join (' '),
-		match }))
-	    .toString () }`)
-	setSuggestionsVsbl (false)
-	setRequest ({ query: '' })
-      }
   }
 
   const handleTagSelect = (tag: Tag) => {
@@ -144,8 +157,9 @@ const TagSearch: FC = () => {
   }, [location.search])
 
   return (
-      <div className="relative w-full">
+      <form onSubmit={handleSubmit} className="relative w-full">
 	<input type="text"
+	       enterKeyHint="search"
 	       data-shortcut-focus-search="true"
 	       placeholder={message ('labels.tagSearch').text}
 	       value={search}
@@ -153,12 +167,18 @@ const TagSearch: FC = () => {
 	       onFocus={() => setSuggestionsVsbl (true)}
 	       onBlur={() => setSuggestionsVsbl (false)}
 	       onKeyDown={handleKeyDown}
+	       onCompositionStart={() => {
+		 compositionFlgRef.current = true
+	       }}
+	       onCompositionEnd={() => {
+		 compositionFlgRef.current = false
+	       }}
 	       className={inputClass (false,
 				      'px-3 py-2 dark:border-gray-600 dark:bg-gray-800 dark:text-white')}/>
 	<TagSearchBox suggestions={suggestionsVsbl && suggestions.length ? suggestions : [] as Tag[]}
 		      activeIndex={activeIndex}
 		      onSelect={handleTagSelect}/>
-      </div>)
+      </form>)
 }
 
 export default TagSearch

frontend/src/components/TopNav.tsx

@@ -29,7 +29,7 @@ import { fetchWikiPage } from '@/lib/wiki'
 import type { FC, MouseEvent } from 'react'
 
 import type { AvailableLocale, LocaleCode } from '@/lib/locales'
-import type { Material, Menu, MenuVisibleItem, Tag, User } from '@/types'
+import type { Material, Menu, MenuVisibleItem, Tag, User, WikiPage } from '@/types'
 
 type Props = {
     user: User | null
@@ -39,10 +39,11 @@ type NavDensity = 'auto' | 'comfortable' | 'compact'
 
 
 export const menuOutline = (
-    { tag, material, wikiId, user, pathName: fullPathname }: {
+    { tag, material, wikiId, wikiResourceType, user, pathName: fullPathname }: {
 	tag?: Tag | null
 	material?: Material | null
 	wikiId: number | null
+	wikiResourceType?: WikiPage['resourceType']
 	user: User | null
 	pathName: string },
 ): Menu => {
@@ -99,17 +100,30 @@ export const menuOutline = (
 	    visible: materialFlg && Boolean (material?.tag) },
 	  { ...message ('history'), to: `/materials/changes?material_id=${ material?.id }`,
 	    visible: materialFlg }] },
-      { ...message ('wiki'), to: '/wiki', subMenu: [
+      ...([
-	  { ...message ('search'), to: '/wiki' },
+	  { key: 'tagDescriptions', path: '/tag-descriptions', type: 'tag_description' },
-	  { ...message ('create'), to: '/wiki/new', visible: editable },
+	  { key: 'tagGroups', path: '/tag-groups', type: 'tag_group' }] as const)
-	  { ...message ('allHistory'), to: '/wiki/changes' },
+	  .map (({ key, path, type }): MenuVisibleItem => {
-	  { ...message ('help'), to: '/wiki/ヘルプ:Wiki' },
+	    const current = (wikiResourceType ?? 'tag_description') === type
-	  { component: <Separator/>, visible: wikiPageFlg },
+	    const detailFlg = wikiPageFlg && current
-	  { ...message ('postsWithCount', { count: postCount }), to: `/posts?tags=${ wikiTitle }`,
+	    const creationPath =
-	    visible: wikiPageFlg },
+		type === 'tag_group'
-	  { ...message ('history'), to: `/wiki/changes?id=${ wikiId }`, visible: wikiPageFlg },
+		? `/wiki/new?title=${ encodeURIComponent ('タググループ:') }` : '/wiki/new'
-	  { ...message ('edit'), to: `/wiki/${ wikiId || wikiTitle }/edit`,
+	    return { ...message (key), to: path,
-	    visible: wikiPageFlg && editable }] },
+		base: (pathName.startsWith ('/wiki') && current) ? '/wiki' : path,
+		subMenu: [
+		    { ...message ('search'), to: path },
+		    { ...message ('create'), to: creationPath, visible: editable },
+		    { ...message ('allHistory'), to: '/wiki/changes' },
+		    { ...message ('help'), to: '/wiki/ヘルプ:Wiki' },
+		    { component: <Separator/>, visible: detailFlg },
+		    { ...message ('postsWithCount', { count: postCount }),
+		      to: `/posts?tags=${ wikiTitle }`, visible: detailFlg },
+		    { ...message ('history'), to: `/wiki/changes?id=${ wikiId }`,
+		      visible: detailFlg },
+		    { ...message ('edit'), to: `/wiki/${ wikiId || wikiTitle }/edit`,
+		      visible: detailFlg && editable }] }
+	  }),
       { ...message ('help'), to: '/help/home', base: '/help', subMenu: [
 	  { ...message ('search'), to: '/help' },
 	  { ...message ('allHistory'), to: '/help/changes' },
@@ -229,7 +243,8 @@ const TopNav: FC<Props> = ({ user, locales, resolveLocaleSwitch }) => {
       queryKey: materialsKeys.show (effectiveTitle, locale),
       queryFn: () => fetchMaterial (effectiveTitle, locale) })
 
-  const menu = menuOutline ({ tag, material, wikiId, user, pathName: location.pathname })
+  const menu = menuOutline ({ tag, material, wikiId,
+      wikiResourceType: wikiPage?.resourceType, user, pathName: location.pathname })
   const visibleMenu = menu.filter ((item): item is MenuVisibleItem => item.visible ?? true)
   const menuLabels = visibleMenu.map (item => item.name).join ('\u0000')
   const moreMenu = menu.filter (item =>

frontend/src/lib/prefetchers.ts

@@ -100,10 +100,11 @@ const prefetchHelpDiff: Prefetcher = async (qc, url, locale) => {
 
 const prefetchWikiPagesIndex: Prefetcher = async (qc, url, locale) => {
   const title = url.searchParams.get ('title') ?? ''
+  const resourceType = url.pathname === '/tag-groups' ? 'tag_group' : 'tag_description'
 
   await qc.prefetchQuery ({
-      queryKey: wikiKeys.index ({ title }, locale),
+      queryKey: wikiKeys.index ({ title, resourceType }, locale),
-      queryFn:  () => fetchWikiPages ({ title }, locale) })
+      queryFn: () => fetchWikiPages ({ title, resourceType }, locale) })
 }
 
 
@@ -310,7 +311,8 @@ export const routePrefetchers: { test: (u: URL) => boolean; run: Prefetcher }[]
 		  && Boolean (mPost (u.pathname))),
       run: prefetchPostShow },
     { test: u => u.pathname === '/posts/changes', run: prefetchPostChanges },
-    { test: u => u.pathname === '/wiki', run: prefetchWikiPagesIndex },
+    { test: u => ['/wiki', '/tag-descriptions', '/tag-groups'].includes (u.pathname),
+      run: prefetchWikiPagesIndex },
     { test: u => (!(['/wiki/new', '/wiki/changes'].includes (u.pathname))
 		  && Boolean (mWiki (u.pathname))),
       run: prefetchWikiPageShow },

frontend/src/lib/queryKeys.ts

@@ -5,6 +5,7 @@ import type {
     FetchPostsParams,
     FetchTagsParams,
     MaterialFilter,
+    WikiPage,
     WikiTagReference } from '@/types'
 
 export const localesKeys = {
@@ -130,7 +131,7 @@ export const wikiKeys = {
     autolinkCandidates: (language: string, locale: LocaleCode) =>
 	['wiki', 'autolink', locale, language] as const,
     index:  (
-    p: { title?: string },
+    p: { title?: string, resourceType?: WikiPage['resourceType'] },
     locale: LocaleCode = 'ja',
 ) => ['wiki', locale, 'index', p] as const,
     show:   (

frontend/src/lib/wiki.ts

@@ -1,6 +1,6 @@
 import { isAxiosError } from 'axios'
 
-import { apiGet } from '@/lib/api'
+import { apiGet, apiPost, apiPut } from '@/lib/api'
 import { switchLocalePath } from '@/lib/locales'
 import { fetchTag, fetchTagByName } from '@/lib/tags'
 
@@ -24,19 +24,54 @@ export const fetchWikiChanges = (
 
 
 export const fetchWikiPages = async (
-    { title }:  { title?: string },
+    { title, resourceType = 'tag_description' }: {
+	title?: string, resourceType?: WikiPage['resourceType'] },
     locale: LocaleCode = 'ja',
-): Promise<WikiPage[]> =>
+): Promise<WikiPage[]> => apiGet (
-    await apiGet ('/wiki', { locale, params: { title } })
+    resourceType === 'tag_group' ? '/tag_groups' : '/tags/descriptions',
+    { locale, params: { title, document: '1' } })
 
 
 export const fetchWikiPage = async (
-    id:           string,
+    id: string,
-    { version }:  { version?: string },
+    { version }: { version?: string },
     locale: LocaleCode = 'ja',
-): Promise<WikiPage> =>
+): Promise<WikiPage> => {
-    await apiGet (`/wiki/${ encodeURIComponent (id) }`, {
+  if (version != null)
-	locale, params: version ? { version } : { } })
+    return apiGet (`/wiki/${encodeURIComponent (id)}`, { locale, params: { version } })
+  try
+  {
+    return await apiGet (`/tags/descriptions/${encodeURIComponent (id)}`,
+	{ locale, params: { document: '1' } })
+  }
+  catch (error)
+  {
+    if (!isAxiosError (error) || error.response?.status !== 404)
+      throw error
+    return apiGet (`/tag_groups/${encodeURIComponent (id)}`,
+	{ locale, params: { document: '1' } })
+  }
+}
+
+
+export const saveTagDocument = async (
+    { title, body, page }: { title: string, body: string, page?: WikiPage },
+    locale: LocaleCode,
+): Promise<WikiPage> => {
+  const groupName = /^(?:タググループ:|tag_group:)(.*)$/i.exec (title.trim ())?.[1]
+  const options = { locale, params: { document: '1' } }
+  if (page?.resourceType === 'tag_group' || (page == null && groupName != null))
+  {
+    const attributes = { name: groupName ?? title.trim (), body }
+    return page == null
+	? apiPost ('/tag_groups', attributes, options)
+	: apiPut (`/tag_groups/${encodeURIComponent (String (page.id))}`, attributes, options)
+  }
+  if (page == null)
+    return apiPost ('/tags/descriptions', { title, body }, options)
+  return apiPut (`/tags/${encodeURIComponent (String (page.tagId))}/description`,
+      { title, body }, options)
+}
 
 
 export const fetchWikiPageByTitle = async (
@@ -46,7 +81,14 @@ export const fetchWikiPageByTitle = async (
 ): Promise<WikiPage | null> => {
   try
   {
-    return await apiGet (`/wiki/title/${ encodeURIComponent (title) }`, { locale, params: { version } })
+    if (version != null)
+      return await apiGet (`/wiki/title/${encodeURIComponent (title)}`,
+	  { locale, params: { version } })
+    const groupName = /^(?:タググループ:|tag_group:)(.*)$/i.exec (title.trim ())?.[1]
+    const path = groupName == null
+	? `/tags/name/${encodeURIComponent (title)}/description`
+	: `/tag_groups/name/${encodeURIComponent (groupName)}`
+    return await apiGet (path, { locale, params: { document: '1' } })
   }
   catch (error)
   {
@@ -72,7 +114,7 @@ export const fetchWikiPageByReference = async (
   {
     if (!isAxiosError (error) || error.response?.status !== 404)
       throw error
-    const tag = await fetchWikiTag ({ wikiId: reference }, locale)
+    const tag = await fetchTagByName (reference, locale)
     return tag == null ? null : fetchWikiPageByTitle (tag.name, params, locale)
   }
 }
@@ -86,7 +128,9 @@ export const fetchWikiTag = async (
     return fetchTagByName (reference.name, locale)
   try
   {
-    return await apiGet (`/wiki/${encodeURIComponent (reference.wikiId)}/tag`, { locale })
+    const page = await fetchWikiPage (reference.wikiId, { }, locale)
+    return (page.resourceType === 'tag_description' && page.tagId != null)
+	? fetchTag (String (page.tagId), locale) : null
   }
   catch (error)
   {

frontend/src/locales/ain-Kana/navigation.json

@@ -14,6 +14,8 @@
   "materials": "チカㇻペ",
   "suppressions": "アエアイカㇷ゚テㇷ゚",
   "wiki": "Wiki",
+  "tagDescriptions": "$t(counts:resources.tag_descriptions)",
+  "tagGroups": "$t(counts:resources.tag_groups)",
   "create": "アシㇼ",
   "edit": "イヌイェㇷ゚",
   "entertainment": "シノッ",

frontend/src/locales/ja/navigation.json

@@ -13,6 +13,8 @@
   "materials": "素材",
   "suppressions": "抑止",
   "wiki": "Wiki",
+  "tagDescriptions": "$t(counts:resources.tag_descriptions)",
+  "tagGroups": "$t(counts:resources.tag_groups)",
   "create": "新規",
   "edit": "編輯",
   "entertainment": "おたのしみ",

frontend/src/pages/materials/MaterialDetailPage.tsx

@@ -135,7 +135,7 @@ const MaterialDetailPage: FC = () => {
 
 	      <TabGroup>
 		{material.tag && (
-		    <Tab name={label ('navigation:wiki')}>
+		    <Tab name={label ('navigation:tagDescriptions')}>
 		      <WikiBody
 			  title={material.tag.name}
 			  language={localeLanguage (locale)}

frontend/src/pages/posts/PostListPage.tsx

@@ -176,7 +176,7 @@ const PostListPage: FC = () => {
 	      {loading && label ('common:loading')}
 	    </Tab>
 	    {tags.length === 1 && (
-		<Tab name={label ('navigation:wiki')}>
+		<Tab name={label ('navigation:tagDescriptions')}>
 		  <WikiBody title={tags[0]} body={wikiPage?.body}
 		      language={wikiPage?.languageCode ?? (wikiPage?.resourceType === 'tag_description'
 			  ? localeLanguage (locale) : 'und')}/>

frontend/src/pages/wiki/WikiDetailPage.tsx

@@ -51,7 +51,8 @@ const WikiDetailPage: FC = () => {
       queryKey: helpKeys.titles ('ja'),
       queryFn: () => getHelpTitleIndex ('ja'),
       staleTime: Infinity })
-  const lookupTitle = title.trim ().normalize ('NFKC').toLowerCase ().replace (/^ヘルプ:/, '')
+  const lookupTitle = title.trim ().normalize ('NFKC').toLowerCase ()
+      .replace (/^(?:ヘルプ|手引):/, '')
   const identifiers = useMemo (() => (
       (titleIndex != null && Object.hasOwn (titleIndex, lookupTitle))
       ? titleIndex[lookupTitle] : []), [titleIndex, lookupTitle])

frontend/src/pages/wiki/WikiEditPage.tsx

@@ -11,8 +11,8 @@ import FormField from '@/components/common/FormField'
 import MainArea from '@/components/layout/MainArea'
 import { toast } from '@/components/ui/use-toast'
 import PageHead from '@/components/common/PageHead'
-import { apiGet, apiPut } from '@/lib/api'
+import { fetchWikiPage, saveTagDocument } from '@/lib/wiki'
-import { wikiKeys } from '@/lib/queryKeys'
+import { tagsKeys, wikiKeys } from '@/lib/queryKeys'
 import { canEditContent } from '@/lib/users'
 import { inputClass } from '@/lib/utils'
 import { useValidationErrors } from '@/lib/useValidationErrors'
@@ -33,7 +33,7 @@ const FIXED_WIKI_EDITOR_VIEW = { menu: true, md: true, html: true } as const
 
 type Props = { user: User | null }
 
-type WikiFormField = 'title' | 'body'
+type WikiFormField = 'title' | 'name' | 'body'
 
 
 const WikiEditPage: FC<Props> = ({ user }) => {
@@ -50,7 +50,7 @@ const WikiEditPage: FC<Props> = ({ user }) => {
   const source = `${locale}:${id}`
   const { data: wiki, isPending: loading } = useQuery ({
       queryKey: wikiKeys.show (id ?? '', { }, locale),
-      queryFn: () => apiGet<WikiPage> (`/wiki/${ encodeURIComponent (id ?? '') }`, { locale }),
+      queryFn: () => fetchWikiPage (id ?? '', { }, locale),
       enabled: editable })
   const [body, setBody] = useState (wiki?.body ?? '')
   const [loadedSource, setLoadedSource] = useState (wiki == null ? '' : source)
@@ -60,22 +60,19 @@ const WikiEditPage: FC<Props> = ({ user }) => {
       useValidationErrors<WikiFormField> ()
 
   const handleSubmit = async () => {
-    if (pending || !editable)
+    if (pending || !editable || wiki == null)
       return
     clearValidationErrors ()
 
-    const formData = new FormData ()
-    formData.append ('title', title)
-    formData.append ('body', body)
-
     try
     {
-      await apiPut (`/wiki/${ id }`, formData,
+      await saveTagDocument ({ title, body, page: wiki }, locale)
-		    { locale, headers: { 'Content-Type': 'multipart/form-data' } })
       qc.setQueryData (wikiKeys.show (title, { }, locale),
 		       (prev: WikiPage | undefined) =>
 			   prev == null ? prev : { ...prev, title, body })
-      qc.invalidateQueries ({ queryKey: wikiKeys.root })
+      await Promise.all ([
+	  qc.invalidateQueries ({ queryKey: wikiKeys.root }),
+	  qc.invalidateQueries ({ queryKey: tagsKeys.root })])
       toast ({ title: label ('shared:messages.postSuccess') })
       navigate (`/wiki/${ encodeURIComponent (title) }`)
     }
@@ -110,7 +107,7 @@ const WikiEditPage: FC<Props> = ({ user }) => {
 
 		{/* タイトル */}
 		{/* TODO: タグ補完 */}
-		<FormField label={label ('shared:labels.title')} messages={fieldErrors.title}>
+		<FormField label={label ('shared:labels.title')} messages={fieldErrors.title ?? fieldErrors.name}>
 		  {({ describedBy, invalid }) => (
 		      <input type="text"
 			     value={title}

frontend/src/pages/wiki/WikiNewPage.tsx

@@ -12,7 +12,7 @@ import FormField from '@/components/common/FormField'
 import MainArea from '@/components/layout/MainArea'
 import { toast } from '@/components/ui/use-toast'
 import PageHead from '@/components/common/PageHead'
-import { apiPost } from '@/lib/api'
+import { saveTagDocument } from '@/lib/wiki'
 import { tagsKeys, wikiKeys } from '@/lib/queryKeys'
 import { canEditContent } from '@/lib/users'
 import { inputClass } from '@/lib/utils'
@@ -21,7 +21,7 @@ import Forbidden from '@/pages/Forbidden'
 
 import type { FC } from 'react'
 
-import type { User, WikiPage } from '@/types'
+import type { User } from '@/types'
 
 const mdParser = new MarkdownIt
 const FIXED_WIKI_EDITOR_VIEW = { menu: true, md: true, html: true } as const
@@ -32,7 +32,7 @@ const FIXED_WIKI_EDITOR_VIEW = { menu: true, md: true, html: true } as const
 
 type Props = { user: User | null }
 
-type WikiFormField = 'title' | 'body'
+type WikiFormField = 'title' | 'name' | 'body'
 
 
 const WikiNewPage: FC<Props> = ({ user }) => {
@@ -55,14 +55,9 @@ const WikiNewPage: FC<Props> = ({ user }) => {
   const handleSubmit = async () => {
     clearValidationErrors ()
 
-    const formData = new FormData
-    formData.append ('title', title)
-    formData.append ('body', body)
-
     try
     {
-      const data = await apiPost<WikiPage> ('/wiki', formData,
+      const data = await saveTagDocument ({ title, body }, locale)
-				  { locale, headers: { 'Content-Type': 'multipart/form-data' } })
       await qc.cancelQueries ({ queryKey: wikiKeys.root })
       qc.setQueryData (wikiKeys.show (data.title, { }, locale), data)
       await Promise.all ([
@@ -91,7 +86,7 @@ const WikiNewPage: FC<Props> = ({ user }) => {
 
 	  {/* タイトル */}
 	  {/* TODO: タグ補完 */}
-	  <FormField label={label ('shared:labels.title')} messages={fieldErrors.title}>
+	  <FormField label={label ('shared:labels.title')} messages={fieldErrors.title ?? fieldErrors.name}>
 	    {({ describedBy, invalid }) => (
 		<input type="text"
 		       value={title}

frontend/src/pages/wiki/WikiSearchPage.tsx

@@ -8,7 +8,7 @@ import FormField from '@/components/common/FormField'
 import PageTitle from '@/components/common/PageTitle'
 import MainArea from '@/components/layout/MainArea'
 import PageHead from '@/components/common/PageHead'
-import { apiGet } from '@/lib/api'
+import { fetchWikiPages } from '@/lib/wiki'
 import { wikiKeys } from '@/lib/queryKeys'
 import { dateString, inputClass } from '@/lib/utils'
 
@@ -17,16 +17,20 @@ import type { FormEvent , FC } from 'react'
 import type { WikiPage } from '@/types'
 
 
-const WikiSearchPage: FC = () => {
+const WikiSearchPage: FC<{ resourceType?: WikiPage['resourceType'] }> = (
+    { resourceType = 'tag_description' },
+) => {
   const { message, label } = useUITranslation ('shared')
   const locale = useLocale ()
+  const heading =
+      resourceType === 'tag_group'
+      ? 'navigation:tagGroups' : 'navigation:tagDescriptions'
   const [title, setTitle] = useState ('')
   const [text, setText] = useState ('')
   const [submittedTitle, setSubmittedTitle] = useState ('')
   const { data: results = [], refetch } = useQuery ({
-      queryKey: wikiKeys.index ({ title: submittedTitle }, locale),
+      queryKey: wikiKeys.index ({ title: submittedTitle, resourceType }, locale),
-      queryFn: () => apiGet<WikiPage[]> ('/wiki', {
+      queryFn: () => fetchWikiPages ({ title: submittedTitle, resourceType }, locale) })
-	  locale, params: { title: submittedTitle } }) })
 
   const handleSearch = (ev: FormEvent) => {
     ev.preventDefault ()
@@ -42,10 +46,10 @@ const WikiSearchPage: FC = () => {
 
   return (
       <MainArea>
-	<PageHead title={message ('navigation:wiki')}/>
+	<PageHead title={message (heading)}/>
 
 	<div className="max-w-xl">
-	  <PageTitle>{label ('navigation:wiki')}</PageTitle>
+	  <PageTitle>{label (heading)}</PageTitle>
 	  <form onSubmit={handleSearch} className="space-y-2">
 	    {/* タイトル */}
 	    <FormField label={label ('labels.title')}>