refactor import readers

lib/keygen/exporter/v1/writer.rb

@@ -1,5 +1,7 @@
 # frozen_string_literal: true
 
+require_relative '../writer'
+
 module Keygen
   module Exporter
     module V1

lib/keygen/importer.rb

@@ -1,6 +1,7 @@
 # frozen_string_literal: true
 
 require_relative 'importer/reader'
+require_relative 'importer/version_reader'
 require_relative 'importer/v1/importer'
 
 module Keygen
@@ -11,13 +12,13 @@ class InvalidSecretKeyError < StandardError; end
     extend self
 
     def import(from:, secret_key: nil)
-      reader  = Reader.new(from)
-      version = reader.read_version
+      version_reader = VersionReader.new(from)
+      version        = version_reader.read_version
 
       importer_class = importer_class_for(version:)
       importer       = importer_class.new(secret_key:)
 
-      importer.import(reader:)
+      importer.import(from:)
     rescue OpenSSL::Cipher::CipherError
       raise InvalidSecretKeyError.new, 'Secret key is invalid'
     end

lib/keygen/importer/reader.rb

@@ -5,8 +5,6 @@ module Importer
     class Reader
       def initialize(io) = @io = io
       def read(n)        = @io.read(n)
-      def read_version   = read(1).unpack1('C') # first byte is the version
-      def read_chunk     = raise NotImplementedError
     end
   end
 end

lib/keygen/importer/v1/importer.rb

@@ -11,10 +11,10 @@ def initialize(secret_key: nil)
           @deserializer = Deserializer.new(secret_key:)
         end
 
-        def import(reader:)
-          v1_reader = Reader.new(reader)
+        def import(from:)
+          reader = Reader.new(from)
 
-          while chunk = v1_reader.read_chunk
+          while chunk = reader.read_chunk
             process_chunk(chunk)
           end
         end

lib/keygen/importer/v1/reader.rb

@@ -1,5 +1,7 @@
 # frozen_string_literal: true
 
+require_relative '../reader'
+
 module Keygen
   module Importer
     module V1

lib/keygen/importer/version_reader.rb

@@ -0,0 +1,11 @@
+# frozen_string_literal: true
+
+require_relative 'reader'
+
+module Keygen
+  module Importer
+    class VersionReader < Reader
+      def read_version = read(1).unpack1('C') # first byte is the version
+    end
+  end
+end