root/lang/ruby/path_observer/tags/path_observer-0.0.1/lib/path_observer/observe_manager.rb @ 3612

require File.expand_path(File.join(File.dirname(__FILE__), '..', 'path_observer'))

module PathObserver
  class ObserveManager
    include Observable

    def initialize glob_expr=nil, interval=1, &event_action
      @interval = interval

      if glob_expr
        add_paths glob_expr, &event_action
      end
    end

    attr_accessor :interval

    def add_path path, &event_action
      add_observer(PathObserver::Observer.new(path, &event_action))
    end

    def add_paths glob_expr, &event_action
      Path.glob(glob_expr).each do |path|
        add_path path, &event_action
      end
    end

    def observe method
      last_result_of = {}
      @observer_peers.each do |observer|
        last_result_of[observer.path.to_s] = observer.path __send__(method)
      end

      loop do
        begin
          sleep @interval

          current_result_of = {}
          @observer_peers.each do |observer|
            current_result_of[observer.path.to_s] = observer.path.__send__(method)
          end

          temp_touple = current_result_of.select {|key, val| val != last_result_of[key] }
          if temp_touple.size > 0
            temp_touple.each do |hash|
              changed
              notify_observers hash.first, hash.last 
            end
            last_result_of = current_result_of
          end
        rescue Interrupt
          return
        rescue Exception
          next
        end
      end
    end
  end
end