#55

backend/app/controllers/posts_controller.rb

@@ -92,7 +92,8 @@ class PostsController < ApplicationController
     q = q.except(:select, :order)
 
     render json: { posts: posts.map { |post|
-      PostRepr.base(post).merge(updated_at: post.updated_at_all).tap do |json|
+      PostRepr.base(post, language_code: locale.language_code)
+              .merge(updated_at: post.updated_at_all).tap do |json|
         json['thumbnail'] =
             if post.thumbnail.attached?
               rails_storage_proxy_url(post.thumbnail, only_path: false)
@@ -116,7 +117,7 @@ class PostsController < ApplicationController
         .first
     return head :not_found unless post
 
-    render json: PostRepr.base(post, current_user)
+    render json: PostRepr.base(post, current_user, language_code: locale.language_code)
   end
 
   def metadata
@@ -191,6 +192,8 @@ class PostsController < ApplicationController
   end
 
   def show
+    locale = resolve_locale!
+
     post =
         Post
         .includes(:uploaded_user, :parents, :children,
@@ -209,8 +212,9 @@ class PostsController < ApplicationController
                                  parent_posts:,
                                  child_posts:,
                                  sibling_posts:,
-                                 related:)
-                         .merge(tags: build_tag_tree_for(post))
+                                 related:,
+                                 language_code: locale.language_code)
+                         .merge(tags: build_tag_tree_for(post, locale.language_code))
   end
 
   def create
@@ -251,7 +255,7 @@ class PostsController < ApplicationController
                                thumbnail: params[:thumbnail])).create!(locale)
 
     post.reload
-    render json: PostRepr.base(post), status: :created
+    render json: PostRepr.base(post, language_code: locale.language_code), status: :created
   rescue PostCreatePreflight::ValidationFailed => e
     render_validation_error fields: e.fields, base: e.base_errors
   rescue Tag::NicoTagNormalisationError
@@ -379,8 +383,8 @@ class PostsController < ApplicationController
     return render json: conflict_json, status: :conflict if conflict_json
 
     post.reload
-    json = PostRepr.base(post, current_user)
-    json['tags'] = build_tag_tree_for(post)
+    json = PostRepr.base(post, current_user, language_code: locale.language_code)
+    json['tags'] = build_tag_tree_for(post, locale.language_code)
     render json:, status: :ok
   rescue Tag::NicoTagNormalisationError
     render_validation_error fields: { tags: ['ニコニコ・タグは直接指定できません．'] }
@@ -487,7 +491,7 @@ class PostsController < ApplicationController
     end
   end
 
-  def build_tag_tree_for post
+  def build_tag_tree_for post, language_code = 'ja'
     post_tags = post.post_tags.reject { |post_tag| post_tag.tag.deprecated? }
     tags = post_tags.map(&:tag)
     tag_ids = tags.map(&:id)
@@ -517,7 +521,7 @@ class PostsController < ApplicationController
       sections = sections_by_tag_id.fetch(tag_id, [])
 
       if path.include?(tag_id)
-        return TagRepr.inline(tag).merge(children: [], sections:)
+        return TagRepr.inline(tag, language_code:).merge(children: [], sections:)
       end
 
       if memo.key?(tag_id)
@@ -529,7 +533,7 @@ class PostsController < ApplicationController
 
       children = child_ids.filter_map { |cid| build_node.(cid, new_path) }
 
-      memo[tag_id] = TagRepr.inline(tag).merge(children:, sections:)
+      memo[tag_id] = TagRepr.inline(tag, language_code:).merge(children:, sections:)
     end
 
     internal_tags = root_ids.filter_map { |id| build_node.call(id, []) }