Ruby script to rename the NDC2011 torrent files to also show the title (old was "Track3 1020-1120

NDC2011VideoRenamer.rb

#Script to correct NDC video file naming (ie:Track3 1140-1240.mp4 to the correct title)
#This script will parse a specific xml file and rename the NDC2011 videos according to the information in the xml file

#Copy xml text from here: https://gist.github.com/1034721 (thanks to GitHub user dauger)

require 'rexml/document'
require 'pathname'
require 'find'

class NDCSession
  @@DayMapping = {"Day 1" => "Day1 Wednesday",
                  "Day 2" => "Day2 Thursday",
                  "Day 3" => "Day3 Friday"}
  attr_accessor :existing_filepath, :new_filepath

  def initialize (basepath, day, track, title, comments)
    @existing_filepath = nil
    @new_filepath = nil

    if comments and comments.include? "wmv"
      filename_part2 = File.basename(comments)
      filename_part2["wmv"] = "mp4"
      if !(filename_part2.include? "Live")                #These videos does not reference mp4 files
        session_track = track[0,7].gsub(/\s/, '')         #Remove all but track number, remove space
        new_title = title[4..-1].gsub(/[^0-9A-Za-z ]/, '')#Only valid characters, remove beginning of title

        if day
          @existing_filepath = (basepath.to_s + '/' + @@DayMapping[day] + '/' + session_track + " " + filename_part2).strip
          @new_filepath = basepath.to_s + '/' + @@DayMapping[day] + '/' + session_track + " " + new_title + ".mp4"
        end
      end
    end
  end

  def RenameFile
    puts "Renaming file: " + existing_filepath  + " to " + new_filepath
    File.rename(existing_filepath, new_filepath) #comment out this line to only verify correct renaming
  end

  def to_s
    "#@existing_filepath"
  end
end


NDCVideoLocation = Pathname.new(File.join('e:', 'utvikling', 'NDC2011mp4'))
NDCXMLPath = Pathname.new(File.join('e:', 'utvikling', 'NDC2011mp4', 'ndc2011.xml')) #copy xml text into this file
xml = File.read(NDCXMLPath)
doc = REXML::Document.new(xml)
lookup = {}
doc.elements.each('TODOLIST/TASK/TASK/TASK') do |taskelement|
    ndcsession = NDCSession.new(  NDCVideoLocation,
                                  taskelement.parent.parent.attributes['TITLE'],
                                  taskelement.parent.attributes['TITLE'],
                                  taskelement.attributes['TITLE'],
                                  taskelement.attributes['COMMENTS'])
    if ndcsession.existing_filepath
      lookup[ndcsession.existing_filepath] = ndcsession
    end
end



Find.find(NDCVideoLocation.to_s) do |mp4file|
   if mp4file.match(/\.mp4\Z/)
      if lookup.has_key?(mp4file)
        lookup[mp4file].RenameFile
      else
        puts "No new name found in xml for: " + mp4file
      end
   end
end

I've only tested this script on Windows. Please feel free to add improvements/corrections.