#
# Routing Table
#
# Copyright (C) 2013 NEC Corporation
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License, version 2, as
# published by the Free Software Foundation.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License along
# with this program; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
#

require 'pio'

class RoutingTable
  ADDR_LEN = 32

  def initialize(route = [])
    @db = Array.new(ADDR_LEN + 1) { Hash.new }
    route.each do |each|
      add(each)
    end
  end

  def add(options)
    dest = Pio::IPv4Address.new(options[:destination])
    masklen = options[:masklen]
    prefix = dest.mask(masklen)
    @db[masklen][prefix.to_i] = Pio::IPv4Address.new(options[:nexthop])
  end

  def delete(options)
    dest = Pio::IPv4Address.new(options[:destination])
    masklen = options[:masklen]
    prefix = dest.mask(masklen)
    @db[masklen].delete(prefix.to_i)
  end

  def lookup(dest)
    (0..ADDR_LEN).reverse_each do |masklen|
      prefix = dest.mask(masklen)
      entry = @db[masklen][prefix.to_i]
      return entry if entry
    end
    nil
  end
end

### Local variables:
### mode: Ruby
### coding: utf-8-unix
### indent-tabs-mode: nil
### End: