#require 'plist'
#require 'ox'
require 'rexml/document'

class RewritePlistFile
#  def self.with_prefix(prefix, original)
#    v = Plist::parse_xml(original)
#    files = v['files']
#    v['files'] = files.map{|i|File.join(prefix, i)}
#    v.to_plist()
  #  end
  def self.with_prefix(prefix, original)
    doc = REXML::Document.new(original)
    array_element = REXML::XPath.first(doc, "//key[text()='files']/following-sibling::array")
    array_element.elements.each do |s|
      s.text = File.join(prefix, s.text)
    end
    res = StringIO.new
    formatter = REXML::Formatters::Pretty.new(2)
    formatter.compact = true
    formatter.write(doc, res)
    return res.string
  end
end