Add `tootctl emoji export` (#13534)

* add emoji export command to cli

* fix codeclimate issues

* add error when no matching category was found

* add other suggestions

* exit 1 when no matching category is found

* changes according to suggestions

* 👀

* RubyNein

Y u always autoformat :c

lib/mastodon/emoji_cli.rb

@@ -23,7 +23,7 @@ module Mastodon
       Existing emoji will be skipped unless the --overwrite option
       is provided, in which case they will be overwritten.
 
-      You can specifiy a --category under which the emojis will be
+      You can specify a --category under which the emojis will be
       grouped together.
 
       With the --prefix option, a prefix can be added to all
@@ -72,6 +72,48 @@ module Mastodon
       say("Imported #{imported}, skipped #{skipped}, failed to import #{failed}", color(imported, skipped, failed))
     end
 
+    option :category
+    option :overwrite, type: :boolean
+    desc 'export PATH', 'Export emoji to a TAR GZIP archive at PATH'
+    long_desc <<-LONG_DESC
+      Exports custom emoji to 'export.tar.gz' at PATH.
+
+      The --category option dumps only the specified category.
+      If this option is not specified, all emoji will be exported.
+
+      The --overwrite option will overwrite an existing archive.
+    LONG_DESC
+    def export(path)
+      exported         = 0
+      category         = CustomEmojiCategory.find_by(name: options[:category])
+      export_file_name = File.join(path, 'export.tar.gz')
+
+      if File.file?(export_file_name) && !options[:overwrite]
+        say("Archive already exists! Use '--overwrite' to overwrite it!")
+        exit 1
+      end
+      if category.nil? && options[:category]
+        say("Unable to find category '#{options[:category]}'!")
+        exit 1
+      end
+
+      File.open(export_file_name, 'wb') do |file|
+        Zlib::GzipWriter.wrap(file) do |gzip|
+          Gem::Package::TarWriter.new(gzip) do |tar|
+            scope = !options[:category] || category.nil? ? CustomEmoji.local : category.emojis
+            scope.find_each do |emoji|
+              say("Adding '#{emoji.shortcode}'...")
+              tar.add_file_simple(emoji.shortcode + File.extname(emoji.image_file_name), 0o644, emoji.image_file_size) do |io|
+                io.write Paperclip.io_adapters.for(emoji.image).read
+                exported += 1
+              end
+            end
+          end
+        end
+      end
+      say("Exported #{exported}")
+    end
+
     option :remote_only, type: :boolean
     desc 'purge', 'Remove all custom emoji'
     long_desc <<-LONG_DESC