allow user to change his language in his settings

app/controllers/application_controller.rb

@@ -3,6 +3,7 @@
 #   the COPYRIGHT file.
 
 class ApplicationController < ActionController::Base
+  include LanguageHelper
 
   protect_from_forgery :except => :receive
 
@@ -36,6 +37,10 @@ class ApplicationController < ActionController::Base
   end
 
   def set_locale
-    I18n.locale = request.compatible_language_from I18n.available_locales
+    if current_user
+      I18n.locale = current_user.language
+    else
+      I18n.locale = request.compatible_language_from AVAILABLE_LANGUAGE_CODES
+    end
   end
 end

app/controllers/users_controller.rb

@@ -29,6 +29,7 @@ class UsersController < ApplicationController
     else
       params[:user].delete(:password) if params[:user][:password].blank?
       params[:user].delete(:password_confirmation) if params[:user][:password].blank? and params[:user][:password_confirmation].blank?
+      params[:user].delete(:language) if params[:user][:language].blank?
 
       if params[:user][:password] && params[:user][:password_confirmation]
         if @user.update_attributes(:password => params[:user][:password], :password_confirmation => params[:user][:password_confirmation])
@@ -36,6 +37,12 @@ class UsersController < ApplicationController
         else
           flash[:error] = "Password Change Failed"
         end
+      elsif params[:user][:language]
+        if @user.update_attributes(:language => params[:user][:language])
+          flash[:notice] = "Language Changed"
+        else
+          flash[:error] = "Language Change Failed"
+        end
       end
 
       redirect_to edit_user_path(@user)

app/helpers/language_helper.rb

@@ -0,0 +1,9 @@
+module LanguageHelper
+  def available_language_options
+    options = []
+    AVAILABLE_LANGUAGES.each do |locale, language|
+      options << [language, locale]
+    end
+    options.sort_by { |o| o[0] }
+  end
+end

app/models/user.rb

@@ -19,6 +19,7 @@ class User
   include MongoMapper::Document
   include Diaspora::UserModules
   include Encryptor::Private
+  include LanguageHelper
 
   plugin MongoMapper::Devise
 
@@ -42,11 +43,15 @@ class User
 
   key :getting_started, Boolean, :default => true
 
+  key :language, String
+
   before_validation :strip_username, :on => :create
+  before_validation :set_current_language, :on => :create
   validates_presence_of :username
   validates_uniqueness_of :username, :case_sensitive => false
   validates_format_of :username, :with => /\A[A-Za-z0-9_.]+\z/ 
   validates_with InvitedUserValidator
+  validates_inclusion_of :language, :in => AVAILABLE_LANGUAGE_CODES
 
   one :person, :class_name => 'Person', :foreign_key => :owner_id
   validate :person_is_valid
@@ -75,6 +80,10 @@ class User
     end
   end
 
+  def set_current_language
+    self.language = I18n.locale.to_s if self.language.blank?
+  end
+
   def self.find_for_authentication(conditions={})
     if conditions[:username] =~ /^([\w\.%\+\-]+)@([\w\-]+\.)+([\w]{2,})$/i # email regex
       conditions[:email] = conditions.delete(:username)

app/views/users/edit.html.haml

@@ -45,6 +45,16 @@
       or
       = f.submit 'Change password'
 
+  %h3 Change language
+  = form_for @user do |f|
+    = f.error_messages
+
+    %p
+      = f.select :language, available_language_options
+      = f.submit 'Change language'
+
+  %br
+
   %h3 Export Data
   = link_to "download my xml", users_export_path, :class => "button"
   = link_to "download my photos", users_export_photos_path, :class => "button"

config/environment.rb

@@ -18,6 +18,18 @@ if File.exists?(File.expand_path("./config/fb_config.yml"))
 else
   FACEBOOK   = false
 end
+
+if File.exists?(File.expand_path("./config/languages.yml"))
+  languages = YAML::load(File.open(File.expand_path("./config/languages.yml")))
+  AVAILABLE_LANGUAGES = languages['available']
+  DEFAULT_LANGUAGE = languages['default']
+  AVAILABLE_LANGUAGE_CODES = languages['available'].keys.map { |v| v.to_s}
+else
+  AVAILABLE_LANGUAGES = { :en => 'English' }
+  DEFAULT_LANGUAGES = 'en'
+  AVAILABLE_LANGUAGE_CODES = ['en']
+end
+
 # Initialize the rails application
 Diaspora::Application.initialize!
 

config/languages.yml

@@ -0,0 +1,17 @@
+default: 'en'
+available:
+  cs: 'Lietuviškai'
+  cy: 'Cymraeg'
+  de: 'Deutsch'
+  en: 'English'
+  es: 'Español'
+  fr: 'Français'
+  id: 'Bahasa Indonesia'
+  it: 'Italiano'
+  nb: 'Norske'
+  nl: 'Nederlandse'
+  pt-BR: 'Português'
+  ro: 'Română'
+  ru: 'Россию'
+  sv: 'Svenska'
+  tr: 'Türk'

spec/controllers/users_controller_spec.rb

@@ -10,6 +10,7 @@ describe UsersController do
   let!(:aspect) { user.aspect(:name => "lame-os") }
 
   let!(:old_password) { user.encrypted_password }
+  let!(:old_language) { user.language }
     
   before do
     sign_in :user, user
@@ -47,5 +48,13 @@ describe UsersController do
         user.encrypted_password.should == old_password
       end
     end
+
+    describe 'language' do
+      it 'should allow user to change his language' do
+        put("update", :id => user.id, "user" => {"language" => "fr"})
+        user.reload
+        user.language.should_not == old_language
+      end
+    end
   end
 end

spec/models/user_spec.rb

@@ -91,6 +91,19 @@ describe User do
         duplicate_user.should_not be_valid
       end
     end
+
+    describe "of language" do
+      it "requires availability" do
+        user = Factory.build(:user, :language => 'some invalid language')
+        user.should_not be_valid
+      end
+
+      it "should save with current language if blank" do
+        I18n.locale = :fr
+        user = Factory(:user, :language => nil)
+        user.language.should == 'fr'
+      end
+    end
   end
 
   describe ".build" do