# Author::    Nicolas Pouillard  <ertai@lrde.epita.fr>.
# Copyright:: Copyright (c) 2005 Nicolas Pouillard. All rights reserved.
# License::   GNU General Public License (GPL).
# Revision::  $Id: runner.rb 221 2005-05-09 12:40:57Z ertai $

module Commands

  module Runners

    class Runner

      abstract

      include Hookable
      include Hooker


      #
      # Hooks declaration
      #

      hook_declare :display_command
      hook_declare :data
      hook_declare :before_open
      hook_declare :before_chdir
      hook_declare :before_exec
      hook_declare :exec


      #
      # Construction methods.
      #

      def initialize
        @command_data_factory = Datas::Factory.new
        hooker_subscribe self
        # hooker_subscribe VerboseHooker.new
      end


      #
      # Methods.
      #

      def run ( aCommand )
        unless aCommand.is_a? Commands::Command
          raise ArgumentError, 'Need a Runner::Command'
        end

        hook_trigger :display_command, aCommand

        data = @command_data_factory.create
        data.input = aCommand.input
        data.output = aCommand.output
        data.error = aCommand.error
        hook_trigger :data, aCommand, data

        run_impl(aCommand, data)

        data
      end

      def run_impl ( aCommand, data )
        hook_trigger :before_open, data
        STDIN.reopen(data.input.to_io) unless data.input.nil?
        STDOUT.reopen(data.output.to_io) unless data.output.nil?
        STDERR.reopen(data.error.to_io) unless data.error.nil?

        hook_trigger :before_chdir, data
        Dir.chdir(aCommand.dir) unless aCommand.dir.nil?

        hook_trigger :before_exec, aCommand, data
        hook_trigger :exec, aCommand, data
      end

      class VerboseHooker
        include Hooker

        def log ( m, *a )
          STDERR.puts
          STDERR.puts "#{m}: #{a.inspect}"
        end

        hook_default_method :log

      end # class VerboseHooker


    end # class Runner



    if $0 == __FILE__
      require 'test/unit'

      class RunnerTest < Test::Unit::TestCase

        def test_abstract
          assert_raise(TypeError) { Runner.new }
        end

      end # class RunnerTest
    end

  end # module Runners

end # module Commands