class GdsApi::Response::CacheControl

def initialize(value = nil)
  super()
  parse(value)
end

def max_age
  self["max-age"].to_i if key?("max-age")
end

def must_revalidate?
  self["must-revalidate"]
end

def no_cache?
  self["no-cache"]
end

def no_store?
  self["no-store"]
end

def parse(header)
  return if header.nil? || header.empty?
  header.scan(PATTERN).each do |name, value|
    self[name.downcase] = value || true
  end
end

def private?
  self["private"]
end

def proxy_revalidate?
  self["proxy-revalidate"]
end

def public?
  self["public"]
end

def reverse_max_age
  self["r-maxage"].to_i if key?("r-maxage")
end

def shared_max_age
  self["s-maxage"].to_i if key?("r-maxage")
end

def to_s
  directives = []
  values = []
  each do |key, value|
    if value == true
      directives << key
    elsif value
      values << "#{key}=#{value}"
    end
  end
  (directives.sort + values.sort).join(", ")
end