require 'custodian/settings'
require 'custodian/testfactory'
require 'socket'
require 'timeout'


#
#  The TCP-protocol test.
#
#  This object is instantiated if the parser sees a line such as:
#
###
### foo.vm.bytemark.co.uk must run tcp on 22 with banner 'ssh' otherwise 'ssh fail'.
###
#
#  The specification of the port is mandatory, the banner is optional.
#
module Custodian

  module ProtocolTest

    class TCPTest < TestFactory


      #
      # The input line from which we were constructed.
      #
      attr_reader :line


      #
      # The host to test against.
      #
      attr_reader :host


      #
      # The port to connect to.
      #
      attr_reader :port


      #
      # Is this test inverted?
      #
      attr_reader :inverted


      #
      #  The banner to look for, may be nil.
      #
      attr_reader :banner




      #
      # Constructor
      #
      # Ensure we received a port to run the TCP-test against.
      #
      def initialize( line )

        #
        # Save the line
        #
        @line = line

        #
        # Save the host
        #
        @host  = line.split( /\s+/)[0]


        #
        # Is this test inverted?
        #
        if ( line =~ /must\s+not\s+run\s+/ )
          @inverted = true
        else
          @inverted = false
        end

        #
        # Save the port
        #
        if ( line =~ /on\s+([0-9]+)/ )
          @port = $1.dup
        else
          @port = nil
        end

        #
        # Save the optional banner.
        #
        if ( line =~ /with\s+banner\s+'([^']+)'/ )
          @banner = $1.dup
        else
          @banner = nil
        end

        @error = nil

        if ( @port.nil? )
          raise ArgumentError, "Missing port to test against"
        end
      end




      #
      # Allow this test to be serialized.
      #
      def to_s
        return( @line )
      end



      #
      # Run the test.
      #
      def run_test

        # reset the error, in case we were previously executed.
        @error = nil

        return( run_test_internal( @host, @port, @banner ) )
      end




      #
      # Run the connection test - optionally matching against the banner.
      #
      # If the banner is nil then we're merely testing we can connect and
      # send the string "quit".
      #
      #
      def run_test_internal( host, port, banner = nil, do_read = false )

        #
        # Get the timeout period for this test.
        #
        settings = Custodian::Settings.instance()
        period   = settings.timeout()

        begin
          timeout(period) do
            begin
              socket = TCPSocket.new( host, port )

              # read a banner from the remote server, if we're supposed to.
              read = nil
              read = socket.sysread(1024) if ( do_read )

              # trim to a sane length & strip newlines.
              read = read[0,255] unless ( read.nil? )
              read.gsub!(/[\n\r]/, "") unless ( read.nil? )

              socket.close()

              if ( banner.nil? )
                @error = nil
                return true
              else
                # test for banner
                if ( ( !read.nil? ) && ( banner.match(read) ) )
                  return true
                end

                @error = "We expected a banner matching '#{banner}' but we got '#{read}'"
                return false
              end
            rescue
              @error = "Exception connecting to host #{host}:#{port} - #{$!}"
              return false
            end
          end
        rescue Timeout::Error => e
          @error = "TIMEOUT: #{e}"
          return false
        end
        @error = "Misc failure"
        return false
      end




      #
      # If the test fails then report the error.
      #
      def error
        @error
      end




      register_test_type "tcp"




    end
  end
end