#
# Copyright (C) 2008-2013 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.
#


module Trema
  class Flow


    #
    # Parses a text line of OpenFlow switch's dump-flows command into a Flow
    # object's dynamic created attributes. A line consists of multiple
    # comma separated key=value fields. A key field may have multiple values
    # specified as key=value#1,value#2,..value#n.
    #
    # @param [String] line the text line to parse.
    #
    # @return [self] the object that holds the parsed key=value fields
    #   as attributes.
    #
    def self.parse(line)
      flow = new
      # to simplify parsing
      line.sub!(/actions=.*,.*$/) { | match | match.gsub(/,/, '/') }
      line.strip.split(/[,\s]\s*/).each do | each |
        next unless /(.+)=(.+)/ =~ each
        name, value = $1, $2
        attr_reader name.to_sym
        if (/\A\d+\Z/ =~ value) || (/\A0x.+\Z/ =~ value)
          flow.instance_eval "@#{ name }=#{ value }"
        else
          flow.instance_eval "@#{ name }='#{ value }'"
        end
      end
      flow
    end


    # @return [Boolean] whether a flow is a user registered flow or not.
    def users_flow?
      not ((@actions == 'drop' && @priority == 0) ||
           @actions == 'CONTROLLER:65535')
    end
  end
end


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