#! /usr/bin/env ruby
# -*- ruby -*-

if ( (`which portversion`.chomp.size < 1) or
       (`which portupgrade`.chomp.size < 1) )
  abort "You need to install portupgrade first !"
end

puts "Have you executed PORTSNAP or CVSUP recently ?"
puts "Please wait for a while."

#
# Manipulating Upgradable Ports
#
class UpgradablePorts

  def initialize
    @needupgrade   = Hash.new()
    @pkgdb_correct = false

    make_list()
    store_versions()
  end # of new()

  #
  # List up upgradable ports with 'portversion' command
  #
  # without version detail
  #
  def make_list()
    open( '| portversion' ).each { |line|
      if ( /^([^\s]+)\s+\</ =~ line )
        @needupgrade.store( $1, false )
      end
    }
  end # of make_list()

  #
  # Storing two version infos, current installed one and latest one
  # with 'portupgrade -n' command
  #
  def store_versions()
    @needupgrade.each_key { |port|
      open( '| portupgrade -n ' + port + ' 2>&1' ).each { |line|
        if ( /Upgrading '(.*)' to '(.*)'/ =~ line )
          @needupgrade.store( $1, $2 )
        elsif ( /Listing the results/ =~ line )
          # This line will appear if portupgrade terminate normally.
          @pkgdb_correct = true
        end
      }
    }
  end # of store_versions()

  #
  # Output result
  #
  def output()
    if ( @needupgrade.size > 0 )
      maxlength = 0
      @needupgrade.each_key { |portname|
        if ( portname.length > maxlength )
          maxlength = portname.length
        end
      }

      @needupgrade.keys.sort.each { |port|
        if ( @needupgrade[port] != false )
          printf( "%-*s --> %s\n", maxlength, port, @needupgrade[port] )
        end
      }
    elsif ( @pkgdb_correct == true )
      puts "All ports are up-to-date ! Congratulation !"
    else
      puts "Something wrong with ``pkgdb'', maybe ? "
    end
  end # of output()

end # of class UpgradablePorts

#
# main()
#
list = UpgradablePorts.new()
list.output()