class ActionDispatch::HostAuthorization::Permissions

def allows?(host)
  @hosts.any? do |allowed|
    if allowed.is_a?(IPAddr)
      begin
        allowed === extract_hostname(host)
      rescue
        # IPAddr#=== raises an error if you give it a hostname instead of
        # IP. Treat similar errors as blocked access.
        false
      end
    else
      allowed === host
    end
  end
end

def empty?
  @hosts.empty?
end

def extract_hostname(host)
  host.slice(VALID_IP_HOSTNAME, "host") || host
end

def initialize(hosts)
  @hosts = sanitize_hosts(hosts)
end

def sanitize_hosts(hosts)
  Array(hosts).map do |host|
    case host
    when Regexp then sanitize_regexp(host)
    when String then sanitize_string(host)
    else host
    end
  end
end

def sanitize_regexp(host)
  /\A#{host}#{PORT_REGEX}?\z/
end

def sanitize_string(host)
  if host.start_with?(".")
    /\A#{SUBDOMAIN_REGEX}?#{Regexp.escape(host[1..-1])}#{PORT_REGEX}?\z/i
  else
    /\A#{Regexp.escape host}#{PORT_REGEX}?\z/i
  end
end