#-- vim:sw=2:et
#++
#
# :title: Shell Plugin for RBot
#
# Author:: Yaohan Chen <yaohan.chen@gmail.com>
# Copyright:: (C) 2008 Yaohan Chen
# License:: GPLv2


require 'treetop'

Treetop.load_string <<END_TREETOP_CODE

grammar Shell
  rule command
    interpolation /
    simple {
      def execute(&block)
        yield text_value
      end
   }
  end

  rule interpolation
    before:simple? "$(" command ")" after:simple? {
      def depth
        command.depth + 1
      end

      def execute(&block)
        yield before.text_value + command.execute(&block) + after.text_value
      end
    }
  end

  rule simple
    (!"$(" !")" .)+ {
      def depth
        0
      end
    }
  end
end

END_TREETOP_CODE


class ShellPlugin < Plugin
  def initialize
    @parser = ShellParser.new
  end

  def shell(m, params)
    result = @parser.parse(params[:command]).execute do |s|
      replies = []
      m = fake_message(s, :delegate => false)
      m.send(:define_method, :reply) do |s|
        replies << s
      end
      replies.join(' ')
    end
    m.reply result
  end
end


plugin = ShellPlugin.new
plugin.map 'shell *command'