A script to convert your source code`s calls to _() (gettext) to t() (ruby i18n).

gettext2rubyi18n.rb

#!/usr/bin/env ruby
#
# https://gist.github.com/brauliobo/5512890
# Authors: Bráulio Bhavamitra <brauliobo@gmail.com> and Hugo Melo <hugo@riseup.net>
# License: GPLv3
#
# A script to convert your source code`s calls to _() (gettext) to t() (ruby i18n).
#
# Convert text string to a key along with the file path. Example:
# Call _('Name') into source views/profile/index.index output into config/locales/en.yml:
# views:
#   profile:
#     index:
#       name: Name
#
# Also extract translations from po folders and output to respective yml files in config/locales.
#
# Limitations:
#   - Only work within Rails.root directory
#   - Ignore calls of _() with multiline strings
#   - Can't update yml multiple times
#

### Configurations
SourcePath = 'plugins/distribution'
I18nRootKey = 'distribution_plugin'
CodeLocale = 'en'
PoDir = 'po'
PoFile = 'noosfero.po'
Locales = Dir.chdir(PoDir){ Dir.glob('*').select{ |f| File.directory?(f) } }
KeyTrimSize = 20

require 'rubygems'
require 'ya2yaml'
require File.expand_path(File.join(File.dirname(__FILE__), 'config', 'environment'))
require 'i18n/gettext'
require 'i18n/gettext/po_parser'

class PoData < Hash
  def set_comment(msgid_or_sym, comment)
    # ignore
  end
end
class Hash
  def deep_copy
    Marshal.load(Marshal.dump(self))
  end
end

# result strings for yml
$strings = {CodeLocale => {}}

class CodeFile
  SingleQuoteText = /[N]?_\('([^']+)'\)/
  DoubleQuoteText = /[N]?_\("([^"]+)"\)/

  attr_accessor :filename
  attr_accessor :i18n_path
  attr_accessor :outdata
  attr_accessor :strings

  def initialize filename
    @filename = filename
    @strings = {}

    @i18n_path = filename.chomp File.extname(filename)
    @i18n_path = @i18n_path.chomp File.extname(@i18n_path)
    @i18n_path = @i18n_path.gsub("#{SourcePath}/", '').split('/')

    unless I18nRootKey.blank?
      # remove/ignore I18nPrefix in parts of path
      @i18n_path = [I18nRootKey] + @i18n_path.map do |file|
        next if file == I18nRootKey
        file.gsub /#{I18nRootKey}_?/, ''
      end.compact
    end
  end

  def i18n_method_available?
    basename = File.basename filename
    not (basename.end_with? '.rb' and not basename.index 'controller')
  end

  def i18n_method
    @i18n_method ||= i18n_method_available? ? 't' : 'I18n.t'
  end

  def add_key text
    key = text.parameterize.underscore.to_s
    key = key[0..KeyTrimSize]
    key = text if key.blank?
    @strings[key] = text
    key
  end

  def migrate_texts
    @outdata = File.open(filename).map do |line|
      begin
        if line =~ SingleQuoteText
          regexp = SingleQuoteText
          text = $1
        elsif line =~ DoubleQuoteText
          regexp = DoubleQuoteText
          text = $1
        else
          text = nil
        end

        if text
          key = add_key text
          line.sub! regexp, "#{i18n_method}('#{i18n_path.join '.'}.#{key}')"
        end
      end while text
      line
    end
  end
end

def read_sources
  Dir.glob("#{SourcePath}/**/*").each do |filename|
    next unless File.file?(filename)

    cf = CodeFile.new filename
    cf.migrate_texts
    next if cf.strings.empty?

    # build hash from path parts
    file_hash = $strings[CodeLocale]
    cf.i18n_path.size.times do |i|
      value = cf.i18n_path[i+1]
      file_hash[cf.i18n_path[i]] ||= value ? {cf.i18n_path[i+1] => {}} : {}
      file_hash = file_hash[cf.i18n_path[i]]
    end
    file_hash.update cf.strings

    # write file
    File.open(filename, 'w'){ |o| o << cf.outdata }
  end
end

def read_pos
  def process po, hash
    hash.each do |key, text|
      next hash[key] = process(po, text) if text.is_a?(Hash)
      text = po[text] if po[text]
      hash[key] = text
    end
  end

  Locales.each do |locale|
    po = nil
    silence_stream(STDERR) do
      po = GetText::PoParser.new.parse(File.read("#{PoDir}/#{locale}/#{PoFile}"), PoData.new)
    end
    $strings[locale] = $strings[CodeLocale].deep_copy
    $strings[locale] = process po, $strings[locale]
  end
end

def write_yml
  locales = ['pt', 'en']
  locales.each do |locale|
    File.open("config/locales/#{locale}.yml", 'a') do |f|
      y = {locale => $strings[locale]}.ya2yaml(:syck_compatible => true).split("\n")
      y = y[2..(y.size)].join("\n")
      f << "\n#{y}"
    end
  end
end

read_sources
read_pos
write_yml