#84

backend/lib/tasks/sync_nico.rake

@@ -5,12 +5,30 @@ namespace :nico do
     require 'open-uri'
     require 'nokogiri'
 
-    fetch_thumbnail = -> url {
+    fetch_thumbnail = -> url do
       html = URI.open(url, read_timeout: 60, 'User-Agent' => 'Mozilla/5.0').read
       doc = Nokogiri::HTML(html)
 
       doc.at('meta[name="thumbnail"]')&.[]('content').presence
-    }
+    end
+
+    def sync_post_tags! post, desired_tag_ids
+      desired_ids = desired_tag_ids.compact.to_set
+      current_ids = post.tags.pluck(:id).to_set
+
+      to_add = desired_ids - current_ids
+      to_remove = current_ids - desired_ids
+
+      Tag.where(id: to_add.to_a).find_each do |tag|
+        begin
+          PostTag.create!(post:, tag:)
+        rescue ActiveRecord::RecordNotUnique
+          ;
+        end
+      end
+
+      PostTag.where(post_id: post.id, tag_id: to_remove.to_a).kept.find_each(&:discard!)
+    end
 
     mysql_user = ENV['MYSQL_USER']
     mysql_pass = ENV['MYSQL_PASS']
@@ -19,43 +37,53 @@ namespace :nico do
         { 'MYSQL_USER' => mysql_user, 'MYSQL_PASS' => mysql_pass },
         'python3', "#{ nizika_nico_path }/get_videos.py")
 
-    if status.success?
-      data = JSON.parse(stdout)
-      data.each do |datum|
-        post = Post.where('url LIKE ?', '%nicovideo.jp%').find { |post|
-          post.url =~ %r{#{ Regexp.escape(datum['code']) }(?!\d)}
-        }
-        unless post
-          title = datum['title']
-          url = "https://www.nicovideo.jp/watch/#{ datum['code'] }"
-          thumbnail_base = fetch_thumbnail.(url) || '' rescue ''
-          post = Post.new(title:, url:, thumbnail_base:, uploaded_user: nil)
-          if thumbnail_base.present?
-            post.thumbnail.attach(
-                io:           URI.open(thumbnail_base),
-                filename:     File.basename(URI.parse(thumbnail_base).path),
-                content_type: 'image/jpeg')
-          end
-          post.save!
-          post.resized_thumbnail!
-        end
+    abort unless status.success?
 
-        current_tags = post.tags.where(category: 'nico').pluck(:name).sort
-        new_tags = datum['tags'].map { |tag| "nico:#{ tag }" }.sort
-        if current_tags != new_tags
-          post.tags.destroy(post.tags.where(name: current_tags))
-          tags_to_add = []
-          new_tags.each do |name|
-            tag = Tag.find_or_initialize_by(name:) do |t|
-              t.category = 'nico'
-            end
-            tags_to_add.concat([tag] + tag.linked_tags)
-          end
-          tags_to_add << Tag.tagme if post.tags.size < 20
-          tags_to_add << Tag.bot
-          post.tags = (post.tags + tags_to_add).uniq
+    data = JSON.parse(stdout)
+    data.each do |datum|
+      post = Post.where('url LIKE ?', '%nicovideo.jp%').find { |post|
+        post.url =~ %r{#{ Regexp.escape(datum['code']) }(?!\d)}
+      }
+      unless post
+        title = datum['title']
+        url = "https://www.nicovideo.jp/watch/#{ datum['code'] }"
+        thumbnail_base = fetch_thumbnail.(url) || '' rescue ''
+        post = Post.new(title:, url:, thumbnail_base:, uploaded_user: nil)
+        if thumbnail_base.present?
+          post.thumbnail.attach(
+              io:           URI.open(thumbnail_base),
+              filename:     File.basename(URI.parse(thumbnail_base).path),
+              content_type: 'image/jpeg')
         end
+        post.save!
+        post.resized_thumbnail!
       end
+
+      kept_tags = post.tags.reload
+      kept_non_nico_ids = kept_tags.where.not(category: 'nico').pluck(:id).to_set
+
+      desired_nico_ids = []
+      datum['tags'].each do |raw|
+        name = "nico:#{ raw }"
+        tag = Tag.find_or_initialize_by(name:) do |t|
+          t.category = 'nico'
+        end
+        tag.save! if tag.new_record?
+        desired_nico_ids << tag.id
+        desired_nico_ids.concat(tag.linked_tags.pluck(:id))
+      end
+      desired_nico_ids.uniq!
+
+      desired_extra_ids = []
+      desired_extra_ids << Tag.tagme.id if kept_tags.size < 10
+      desired_extra_ids << Tag.bot.id
+      desired_extra_ids.compact!
+      desired_extra_ids.uniq!
+
+      desired_all_ids = kept_non_nico_ids.to_a + desired_nico_ids + desired_extra_ids
+      desired_all_ids.uniq!
+
+      sync_post_tags!(post, desired_all_ids)
     end
   end
 end