module YAML

def self.load_file_with_options(file, options={})
  safe_mode = safe_mode_from_options("load_file", options)
  if safe_mode == :safe
    safe_load_file(file, options_for_safe_load(options))
  else
    unsafe_load_file(file)
  end
end

def self.load_with_options(yaml, *original_arguments)
  filename, options = filename_and_options_from_arguments(original_arguments)
  safe_mode = safe_mode_from_options("load", options)
  arguments = [yaml]
  if safe_mode == :safe
    arguments << filename if SafeYAML::YAML_ENGINE == "psych"
    arguments << options_for_safe_load(options)
    safe_load(*arguments)
  else
    arguments << filename if SafeYAML::MULTI_ARGUMENT_YAML_LOAD
    unsafe_load(*arguments)
  end
end

def self.safe_load(*args)
  SafeYAML.load(*args)
end

def self.safe_load_file(*args)
  SafeYAML.load_file(*args)
end

def self.unsafe_load_file(filename)
  # https://github.com/tenderlove/psych/blob/v1.3.2/lib/psych.rb#L296-298
  File.open(filename, 'r:bom|utf-8') { |f| self.unsafe_load(f, filename) }
end

def self.unsafe_load_file(filename)
  # https://github.com/tenderlove/psych/blob/v1.2.2/lib/psych.rb#L231-233
  self.unsafe_load File.open(filename)
end

def filename_and_options_from_arguments(arguments)
  if arguments.count == 1
    if arguments.first.is_a?(String)
      return arguments.first, {}
    else
      return nil, arguments.first || {}
    end
  else
    return arguments.first, arguments.last || {}
  end
end

def options_for_safe_load(base_options)
  options = base_options.dup
  options.delete(:safe)
  options
end

def safe_mode_from_options(method, options={})
  if options[:safe].nil?
    safe_mode = SafeYAML::OPTIONS[:default_mode] || :safe
    if SafeYAML::OPTIONS[:default_mode].nil? && !SafeYAML::OPTIONS[:suppress_warnings]
      Kernel.warn <<-EOWARNING.gsub(/^\s+/, '')
        Called '#{method}' without the :safe option -- defaulting to #{safe_mode} mode.
        You can avoid this warning in the future by setting the SafeYAML::OPTIONS[:default_mode] option (to :safe or :unsafe).
      EOWARNING
      SafeYAML::OPTIONS[:suppress_warnings] = true
    end
    return safe_mode
  end
  options[:safe] ? :safe : :unsafe
end