class IpAddress < ActiveRecord::Base
  belongs_to  :subnet
  belongs_to  :interface

  def address_string
    IpAddress.long2ip(address)
  end

  def address_string= (ip)
    print "received ip: " << (ip==nil ? "nil" : ip) << "\n"
    address= IpAddress.ip2long(ip)
    print "address now equals: " << address.to_s << "\n"
  end

  def IpAddress.ip2long (ip)
    long = 0
    ip.split(/\./).each_with_index do |b, i|
      if(b.to_i>255)
        #invalid octet.
        return
      end
      if(b.to_i<0)
        #invalid octet.
        return
      end
      long += b.to_i << (8*i)
    end
    long
  end

  def IpAddress.long2ip (long)
    if long == -1
      return
    end
      ip = []
      4.times do |i|
        ip.push(long.to_i & 255)
        long = long.to_i >> 8
      end
      ip.join(".")
  end


end

--- script/console output:
ksmith@ksmith-desktop:~/secnetdb_root$ script/console
Loading development environment (Rails 2.0.2)
>> x= IpAddress.new
=> #<IpAddress id: nil, address: nil, interface_id: nil, subnet_id: nil, comment: "">
>> x.address
=> nil
>> x.address = 1
=> 1
>> x.address
=> 1
>> x.address_string = "10.17.184.1"
received ip: 10.17.184.1
address now equals: 28840202
=> "10.17.184.1"
>> x.address
=> 1
>> x.address_string
=> "1.0.0.0"
>> x.address = 28840202
=> 28840202
>> x.address_string
=> "10.17.184.1"