module Daemons
  class Controller
    
    attr_reader :app_name
    
    attr_reader :group
    
    attr_reader :options
    
    
    COMMANDS = [
      'start',
      'stop',
      'restart',
      'run',
      'zap',
      'status'
    ]
    
    def initialize(options = {}, argv = [])
      @options = options
      @argv = argv
      
      # Allow an app_name to be specified. If not specified use the
      # basename of the script.
      @app_name = options[:app_name]
      
      if options[:script]
        @script = File.expand_path(options[:script])
    
        @app_name ||= File.split(@script)[1]
      end
    
      @app_name ||= 'unknown_application'
      
      @command, @controller_part, @app_part = Controller.split_argv(argv)
    
      #@options[:dir_mode] ||= :script
    
      @optparse = Optparse.new(self)
    end
    
    
    # This function is used to do a final update of the options passed to the application
    # before they are really used.
    #
    # Note that this function should only update <tt>@options</tt> and no other variables.
    #
    def setup_options
      #@options[:ontop] ||= true
    end
    
    def run
      @options.update @optparse.parse(@controller_part).delete_if {|k,v| !v}
      
      setup_options()
      
      #pp @options

      @group = ApplicationGroup.new(@app_name, @options)
      @group.controller_argv = @controller_part
      @group.app_argv = @app_part
      
      @group.setup
      
      case @command
        when 'start'
          @group.new_application.start
        when 'run'
          @options[:ontop] ||= true
          @group.new_application.start
        when 'stop'
          @group.stop_all
        when 'restart'
          unless @group.applications.empty?
            @group.stop_all
            sleep 1
            @group.start_all
          end
        when 'zap'
          @group.zap_all
        when 'status'
          unless @group.applications.empty?
            @group.show_status
          else
            puts "#{@group.app_name}: no instances running"
          end
        when nil
          raise CmdException.new('no command given')
          #puts "ERROR: No command given"; puts
          
          #print_usage()
          #raise('usage function not implemented')
        else
          raise Error.new("command '#{@command}' not implemented")
      end
    end
    
    
    # Split an _argv_ array.
    # +argv+ is assumed to be in the following format:
    #   ['command', 'controller option 1', 'controller option 2', ..., '--', 'app option 1', ...]
    #
    # <tt>command</tt> must be one of the commands listed in <tt>COMMANDS</tt>
    #
    # *Returns*: the command as a string, the controller options as an array, the appliation options
    # as an array
    #
    def Controller.split_argv(argv)
      argv = argv.dup
      
      command = nil
      controller_part = []
      app_part = []
       
      if COMMANDS.include? argv[0]
        command = argv.shift
      end
      
      if i = argv.index('--')
        # Handle the case where no controller options are given, just
        # options after "--" as well (i == 0)
        controller_part = (i == 0 ? [] : argv[0..i-1])
        app_part = argv[i+1..-1]
      else
        controller_part = argv[0..-1]
      end
       
      return command, controller_part, app_part
    end
  end

end