Add message format support that can be used on complex localization strings

Add message about new and unread topics at the bottom of topics
move localization helper into lib

lib/js_locale_helper.rb

@@ -0,0 +1,74 @@
+module JsLocaleHelper
+
+  def self.output_locale(locale, translations = nil)
+
+    locale_str = locale.to_s
+
+    translations ||= YAML::load(File.open("#{Rails.root}/config/locales/client.#{locale_str}.yml"))
+
+    # We used to split the admin versus the client side, but it's much simpler to just
+    # include both for now due to the small size of the admin section.
+    #
+    # For now, let's leave it split out in the translation file in case we want to split
+    # it again later, so we'll merge the JSON ourselves.
+    admin_contents = translations[locale_str].delete('admin_js')
+    translations[locale_str]['js'].merge!(admin_contents) if admin_contents.present?
+    message_formats = strip_out_message_formats!(translations[locale_str]['js'])
+
+    result = generate_message_format(message_formats, locale_str)
+
+    result << "I18n.translations = #{translations.to_json};\n"
+    result << "I18n.locale = '#{locale_str}'\n"
+    result
+  end
+
+  def self.generate_message_format(message_formats, locale_str)
+    formats = message_formats.map{|k,v| k.inspect << " : " << compile_message_format(locale_str ,v)}.join(" , ")
+
+    result = "MessageFormat = {locale: {}};\n"
+    result << File.read(Rails.root + "lib/javascripts/locale/#{locale_str}.js") << "\n"
+
+    result << "I18n.messageFormat = (function(formats){
+      var f = formats;
+      return function(key, options) {
+        var fn = f[key];
+        if(fn){
+          try {
+            return fn(options);
+          } catch(err) {
+            return err.message;
+          }
+        } else {
+          return 'Missing Key: ' + key
+        }
+        return f[key](options);
+      };
+    })({#{formats}});"
+  end
+
+  def self.compile_message_format(locale, format)
+    ctx = V8::Context.new
+    ctx.load(Rails.root + 'lib/javascripts/messageformat.js')
+    ctx.eval("mf = new MessageFormat('#{locale}');")
+    ctx.eval("mf.precompile(mf.parse(#{format.inspect}))")
+
+  rescue V8::Error => e
+    message = "Invalid Format: " << e.message
+    "function(){ return #{message.inspect};}"
+  end
+
+  def self.strip_out_message_formats!(hash, prefix = "", rval = {})
+    if Hash === hash
+      hash.each do |k,v|
+        if Hash === v
+          rval.merge!(strip_out_message_formats!(v, prefix + (prefix.length > 0 ? "." : "") << k, rval))
+        elsif k.end_with?("_MF")
+          rval[prefix + (prefix.length > 0 ? "." : "") << k] = v
+          hash.delete(k)
+        end
+      end
+    end
+    rval
+  end
+
+end