Help correcting header includes in c++ projects

cpp_add_full_header_path.rb

#!/usr/bin/env ruby

require 'optparse'
require 'pathname'

options = {:root => './'}

optparse = OptionParser.new do |opts|
  opts.on('-r', '--root PATH', 'Source Code Root') do |path|
    options[:root] = path
  end

  opts.on('-h', '--help', 'Display this screen') do
    puts opts
    exit
  end
end

begin
  optparse.parse!
  mandatory = [:root]
  missing = mandatory.select{ |param| options[param].nil? }
  if not missing.empty?
    puts "Missing options: #{missing.join(', ')}"
    puts optparse
    exit
  end
rescue OptionParser::InvalidOption, OptionParser::MissingArgument
  puts $!.to_s
  puts optparse
  exit
end

root = Pathname.new(options[:root]).expand_path

header_files = Dir["#{root.to_s}/**/*.h"].map do |file|
  Pathname.new file
end

header_index = {}
gui = Pathname.new "gui"
data = Pathname.new "data"
header_files.each do |header|
  filename = header.expand_path.relative_path_from root
  if (filename.parent.to_s =~ /#{gui.to_s}/) == 0
    filename = filename.relative_path_from gui
  elsif (filename.parent.to_s =~ /#{data.to_s}/) == 0
    filename = filename.relative_path_from data
  end
  header_index[header.basename.to_s] = filename
end

Dir["#{root}/**/*.{h,cpp}"].each do |filename|
  File.open(filename, "r+") do |file|
    buffer = file.readlines
    file.rewind
    file.truncate 0
    buffer.map do |line|
      begin
        match = line.match(/#include "(.+\.h)"/)
        if match and not header_index[match[1]].nil?
          line.sub!(/[^"]+.h/, header_index[match[1]].to_s)
        end
      rescue ArgumentError
        puts line
      end
      line
    end
    file.puts buffer
  end
end