routes: replace hardcoded routes in models with route helpers.

Add a Routes module that gives models access to route helpers outside of
views, and use it to replace various hardcoded routes.

app/logical/d_text.rb

@@ -109,11 +109,11 @@ class DText
       end
 
       if obj.is_approved?
-        "The \"bulk update request ##{obj.id}\":/bulk_update_requests/#{obj.id} has been approved by <@#{obj.approver.name}>.\n\n#{embedded_script}"
+        "The \"bulk update request ##{obj.id}\":#{Routes.bulk_update_request_path(obj)} has been approved by <@#{obj.approver.name}>.\n\n#{embedded_script}"
       elsif obj.is_pending?
-        "The \"bulk update request ##{obj.id}\":/bulk_update_requests/#{obj.id} is pending approval.\n\n#{embedded_script}"
+        "The \"bulk update request ##{obj.id}\":#{Routes.bulk_update_request_path(obj)} is pending approval.\n\n#{embedded_script}"
       elsif obj.is_rejected?
-        "The \"bulk update request ##{obj.id}\":/bulk_update_requests/#{obj.id} has been rejected.\n\n#{embedded_script}"
+        "The \"bulk update request ##{obj.id}\":#{Routes.bulk_update_request_path(obj)} has been rejected.\n\n#{embedded_script}"
       end
     end
   end

app/logical/routes.rb

@@ -0,0 +1,11 @@
+# Allow Rails URL helpers to be used outside of views.
+# Example: Routes.posts_path(tags: "touhou") => /posts?tags=touhou
+
+class Routes
+  include Singleton
+  include Rails.application.routes.url_helpers
+
+  class << self
+    delegate_missing_to :instance
+  end
+end

app/logical/sources/strategies/pixiv.rb

@@ -65,15 +65,15 @@ module Sources
 
         text = text.gsub(%r{https?://www\.pixiv\.net/member_illust\.php\?mode=medium&illust_id=([0-9]+)}i) do |_match|
           pixiv_id = $1
-          %(pixiv ##{pixiv_id} "»":[/posts?tags=pixiv:#{pixiv_id}])
+          %(pixiv ##{pixiv_id} "»":[#{Routes.posts_path(tags: "pixiv:#{pixiv_id}")}])
         end
 
         text = text.gsub(%r{https?://www\.pixiv\.net/member\.php\?id=([0-9]+)}i) do |_match|
           member_id = $1
           profile_url = "https://www.pixiv.net/users/#{member_id}"
-          search_params = {"search[url_matches]" => profile_url}.to_param
+          artist_search_url = Routes.artists_path(search: { url_matches: profile_url })
 
-          %("user/#{member_id}":[#{profile_url}] "»":[/artists?#{search_params}])
+          %("user/#{member_id}":[#{profile_url}] "»":[#{artist_search_url}])
         end
 
         text = text.gsub(/\r\n|\r|\n/, "<br>")

app/logical/upload_service/replacer.rb

@@ -11,7 +11,7 @@ class UploadService
     end
 
     def comment_replacement_message(post, replacement)
-      %("#{replacement.creator.name}":[/users/#{replacement.creator.id}] replaced this post with a new image:\n\n#{replacement_message(post, replacement)})
+      %("#{replacement.creator.name}":[#{Routes.user_path(replacement.creator)}] replaced this post with a new image:\n\n#{replacement_message(post, replacement)})
     end
 
     def replacement_message(post, replacement)

app/logical/user_promotion.rb

@@ -32,16 +32,16 @@ class UserPromotion
 
   def create_mod_actions
     if old_can_approve_posts != user.can_approve_posts?
-      ModAction.log("\"#{promoter.name}\":/users/#{promoter.id} changed approval privileges for \"#{user.name}\":/users/#{user.id} from #{old_can_approve_posts} to [b]#{user.can_approve_posts?}[/b]", :user_approval_privilege)
+      ModAction.log("\"#{promoter.name}\":#{Routes.user_path(promoter)} changed approval privileges for \"#{user.name}\":#{Routes.user_path(user)} from #{old_can_approve_posts} to [b]#{user.can_approve_posts?}[/b]", :user_approval_privilege, promoter)
     end
 
     if old_can_upload_free != user.can_upload_free?
-      ModAction.log("\"#{promoter.name}\":/users/#{promoter.id} changed unlimited upload privileges for \"#{user.name}\":/users/#{user.id} from #{old_can_upload_free} to [b]#{user.can_upload_free?}[/b]", :user_upload_privilege)
+      ModAction.log("\"#{promoter.name}\":#{Routes.user_path(promoter)} changed unlimited upload privileges for \"#{user.name}\":#{Routes.user_path(user)} from #{old_can_upload_free} to [b]#{user.can_upload_free?}[/b]", :user_upload_privilege, promoter)
     end
 
     if user.level_changed?
       category = is_upgrade ? :user_account_upgrade : :user_level_change
-      ModAction.log(%{"#{user.name}":/users/#{user.id} level changed #{user.level_string_was} -> #{user.level_string}}, category)
+      ModAction.log(%{"#{user.name}":#{Routes.user_path(user)} level changed #{user.level_string_was} -> #{user.level_string}}, category, promoter)
     end
   end