class MultiJson::Adapter

def blank?(input)
  input.nil? || BLANK_PATTERN.match?(input)
rescue ArgumentError
  # Invalid byte sequence in UTF-8 - treat as non-blank
  false
end

def defaults(action, value)
  instance_variable_set(:"@default_#{action}_options", value.freeze)
end

def dump(object, options = {})
  instance.dump(object, merged_dump_options(options))
end

def inherited(subclass)
  super
  # Propagate default options to subclasses
  subclass.instance_variable_set(:@default_load_options, @default_load_options) if defined?(@default_load_options)
  subclass.instance_variable_set(:@default_dump_options, @default_dump_options) if defined?(@default_dump_options)
end

def load(string, options = {})
  string = string.read if string.respond_to?(:read)
  return nil if blank?(string)
  instance.load(string, merged_load_options(options))
end

def merged_dump_options(options)
  cache_key = strip_adapter_key(options)
  OptionsCache.dump.fetch(cache_key) do
    dump_options(cache_key).merge(MultiJson.dump_options(cache_key)).merge!(cache_key)
  end
end

def merged_load_options(options)
  cache_key = strip_adapter_key(options)
  OptionsCache.load.fetch(cache_key) do
    load_options(cache_key).merge(MultiJson.load_options(cache_key)).merge!(cache_key)
  end
end

def strip_adapter_key(options)
  options.except(:adapter).freeze
end