#386

backend/app/controllers/materials_controller.rb

@@ -89,15 +89,13 @@ class MaterialsController < ApplicationController
 
     begin
       Material.transaction do
-        tag_name = TagName.find_undiscard_or_create_by!(name: tag_name_raw)
-        tag = tag_name.tag
-        tag = Tag.create!(tag_name:, category: :material) unless tag
-
+        tag = resolve_material_tag!(tag_name_raw)
         material = Material.new(tag:, url:,
                                 created_by_user: current_user,
                                 updated_by_user: current_user)
         material.file.attach(uploaded_blob) if uploaded_blob
         material.save!
+        TagVersioning.record_tag_snapshot!(tag, created_by_user: current_user)
         upsert_export_paths!(material)
         MaterialVersionRecorder.record!(material:, event_type: :create,
                                         created_by_user: current_user)
@@ -139,10 +137,7 @@ class MaterialsController < ApplicationController
     begin
       Material.transaction do
         MaterialVersionRecorder.ensure_snapshot!(material, created_by_user: current_user)
-        tag_name = TagName.find_undiscard_or_create_by!(name: tag_name_raw)
-        tag = tag_name.tag
-        tag = Tag.create!(tag_name:, category: :material) unless tag
-
+        tag = resolve_material_tag!(tag_name_raw)
         material.assign_attributes(tag:, url:, updated_by_user: current_user)
         if uploaded_blob
           material.file.attach(uploaded_blob)
@@ -150,6 +145,7 @@ class MaterialsController < ApplicationController
           material.file.detach
         end
         material.save!
+        TagVersioning.record_tag_snapshot!(tag, created_by_user: current_user)
         upsert_export_paths!(material)
         MaterialVersionRecorder.record!(material:, event_type: :update,
                                         created_by_user: current_user)
@@ -240,6 +236,12 @@ class MaterialsController < ApplicationController
     nil
   end
 
+  def resolve_material_tag! tag_name_raw
+    tag_name = TagName.find_undiscard_or_create_by!(name: tag_name_raw)
+    tag = tag_name.tag
+    tag || Tag.create!(tag_name:, category: :material)
+  end
+
   def material_index_needs_tag_name? filters
     filters[:q].present? || filters[:sort] == 'tag_name'
   end