From 4e82a3b3754c3172480b0633c229d92e532b64b2 Mon Sep 17 00:00:00 2001
From: miteruzo <miteruzo@naver.com>
Date: Wed, 11 Feb 2026 17:36:22 +0900
Subject: [PATCH] #124

---
 backend/app/models/tag.rb | 26 +++++++++++++++-----------
 1 file changed, 15 insertions(+), 11 deletions(-)

diff --git a/backend/app/models/tag.rb b/backend/app/models/tag.rb
index 60cc79b..ce064a4 100644
--- a/backend/app/models/tag.rb
+++ b/backend/app/models/tag.rb
@@ -46,12 +46,16 @@ class Tag < ApplicationRecord
   scope :nico_tags, -> { where(category: :nico) }
 
   CATEGORY_PREFIXES = {
-      'gen:'  => :general,
-      'djk:'  => :deerjikist,
-      'meme:' => :meme,
-      'chr:'  => :character,
-      'mtr:'  => :material,
-      'meta:' => :meta }.freeze
+      'general:'    => :general,
+      'gen:'        => :general,
+      'deerjikist:' => :deerjikist,
+      'djk:'        => :deerjikist,
+      'meme:'       => :meme,
+      'character:'  => :character,
+      'chr:'        => :character,
+      'material:'   => :material,
+      'mtr:'        => :material,
+      'meta:'       => :meta }.freeze
 
   def name= val
     (self.tag_name ||= build_tag_name).name = val
@@ -78,13 +82,13 @@ class Tag < ApplicationRecord
   end
 
   def self.normalise_tags tag_names, with_tagme: true, deny_nico: true
-    if deny_nico && tag_names.any? { |n| n.start_with?('nico:') }
+    if deny_nico && tag_names.any? { |n| n.downcase.start_with?('nico:') }
       raise NicoTagNormalisationError
     end
 
     tags = tag_names.map do |name|
-      pf, cat = CATEGORY_PREFIXES.find { |p, _| name.start_with?(p) } || ['', nil]
-      name = TagName.canonicalise(name.delete_prefix(pf)).first
+      pf, cat = CATEGORY_PREFIXES.find { |p, _| name.downcase.start_with?(p) } || ['', nil]
+      name = TagName.canonicalise(name.sub(/\A#{ pf }/i, '')).first
       find_or_create_by_tag_name!(name, category: (cat || :general)).tap do |tag|
         if cat && tag.category != cat
           tag.update!(category: cat)
@@ -134,8 +138,8 @@ class Tag < ApplicationRecord
 
   def nico_tag_name_must_start_with_nico
     n = name.to_s
-    if ((category == 'nico' && !(n.start_with?('nico:'))) || 
-        (category != 'nico' && n.start_with?('nico:')))
+    if ((category == 'nico' && !(n.downcase.start_with?('nico:'))) || 
+        (category != 'nico' && n.downcase.start_with?('nico:')))
       errors.add :name, 'ニコニコ・タグの命名規則に反してゐます．'
     end
   end
-- 
2.34.1