module ActiveModel::Attributes::ClassMethods

def attribute(name, cast_type = nil, default: NO_DEFAULT_PROVIDED, **options)
  name = name.to_s
  cast_type = Type.lookup(cast_type, **options) if Symbol === cast_type
  cast_type ||= attribute_types[name]
  self.attribute_types = attribute_types.merge(name => cast_type)
  define_default_attribute(name, default, cast_type)
  define_attribute_method(name)
end

def attribute_names
  attribute_types.keys
end

def define_default_attribute(name, value, type)
  self._default_attributes = _default_attributes.deep_dup
  if value == NO_DEFAULT_PROVIDED
    default_attribute = _default_attributes[name].with_type(type)
  else
    default_attribute = Attribute::UserProvidedDefault.new(
      name,
      value,
      type,
      _default_attributes.fetch(name.to_s) { nil },
    )
  end
  _default_attributes[name] = default_attribute
end

def define_method_attribute=(name, owner:)
  ActiveModel::AttributeMethods::AttrNames.define_attribute_accessor_method(
    owner, name, writer: true,
  ) do |temp_method_name, attr_name_expr|
    owner.define_cached_method("#{name}=", as: temp_method_name, namespace: :active_model) do |batch|
      batch <<
        "def #{temp_method_name}(value)" <<
        "  _write_attribute(#{attr_name_expr}, value)" <<
        "end"
    end
  end
end