Extract typefactory converter from CLI

typefactory/converter.h

@@ -0,0 +1,29 @@
+#ifndef CONVERTER_H
+#define CONVERTER_H
+
+#include <memory>
+#include <string>
+
+class Converter {
+public:
+  explicit Converter (std::string input_file_name);
+  ~Converter();
+
+  Converter (const Converter &) = delete;
+  Converter &operator= (const Converter &) = delete;
+
+  bool save (const std::string &output_file_name);
+  [[nodiscard]] int error_code() const noexcept;
+
+protected:
+  bool parse();
+
+private:
+  struct Impl;
+
+  std::string input_file_name_;
+  std::unique_ptr<Impl> impl_;
+  int error_code_ = 0;
+};
+
+#endif // CONVERTER_H