rake: add image preview/sample regeneration script.

lib/tasks/images.rake

@@ -4,7 +4,7 @@ namespace :images do
     CurrentUser.user = User.system
     sm = Danbooru.config.backup_storage_manager
     tags = ENV["BACKUP_TAGS"]
-    posts = Post.tag_match(tags)
+    posts = Post.system_tag_match(tags)
 
     posts.find_each do |post|
       sm.store_file(post.file(:preview), post, :preview) if post.has_preview?
@@ -13,4 +13,25 @@ namespace :images do
       sm.store_file(post.file(:original), post, :original)
     end
   end
+
+  desc "Regenerate thumbnails and samples"
+  task :regen => :environment do
+    tags = ENV["TAGS"]
+
+    Post.system_tag_match(tags).find_each do |post|
+      original_file = MediaFile.open(post.file(:original))
+      preview_file, crop_file, sample_file = UploadService::Utils.generate_resizes(original_file)
+
+      line = ""
+      line << "post ##{post.id}: "
+      line << "preview=#{preview_file.width}x#{preview_file.height}:#{preview_file.file_size.to_s(:human_size)} " if preview_file.present?
+      line << "crop=#{crop_file.width}x#{crop_file.height}:#{crop_file.file_size.to_s(:human_size)} " if crop_file.present?
+      line << "sample=#{sample_file.width}x#{sample_file.height}:#{sample_file.file_size.to_s(:human_size)} " if sample_file.present?
+      puts line
+
+      UploadService::Utils.distribute_files(preview_file, post, :preview) if preview_file.present?
+      UploadService::Utils.distribute_files(crop_file, post, :crop) if crop_file.present?
+      UploadService::Utils.distribute_files(sample_file, post, :large) if sample_file.present?
+    end
+  end
 end