require 'rexml/document'
include REXML

if ARGV.empty? then
  puts "Usage: ruby #{$0} DELETED_FILE_PATH"
  puts "Find the revision when a certain path was deleted."
  exit
end

svn_info = `svn info`.split("\n")
class <<svn_info
  def extract_value(key)
    grep(/#{key}:/).first.split(/#{key}:/)[1].chomp.strip;
  end
end

relative_local_path = ARGV.shift
if !relative_local_path.match(/^\//) then
  relative_local_path = "/#{relative_local_path}"
end

url = svn_info.extract_value("URL")
repository_root = svn_info.extract_value("Repository Root")
relative_repos_location = url[/#{repository_root}(.*)/, 1]
deleted_path = relative_repos_location + relative_local_path
xml_log = `svn log -v --xml #{url}`

Document.new(xml_log).elements.each('log/logentry') do |logentry|
  revision = logentry.attributes['revision'].to_i
  logentry.elements.each('paths/path') do |path|
  	if (path.text == deleted_path) then
  		puts "#{deleted_path} deleted in revision #{revision}"
  		puts "To recover it: svn copy -r#{revision-1} #{url}#{relative_local_path} " +
  		   "#{relative_local_path[1..-1]}"
  		exit
  	end
  end
end

puts "Could not find deletion record for #{deleted_path}."
exit 1