# I18n.js

It's a small library to provide the Rails I18n translations on the Javascript.

Features:

- Pluralization
- Date/Time localization
- Number localization
- Locale fallback
- Asset pipeline support
- Lots more! :)

## Usage

### Installation

#### Rails app

Add the gem to your Gemfile.

    source :rubygems
    gem "rails", "3.2.3"
    gem "i18n-js"

If you're using the [asset pipeline](http://guides.rubyonrails.org/asset_pipeline.html),
then you must add the following line to your `app/assets/javascripts/application.js`.

    //= require i18n/translations

If you're not using the asset pipeline, download the JavaScript file at
<https://github.com/fnando/i18n-js/tree/master/lib/i18n.js> and load it on your page.
Also load the `translations.js` file.

    <%= javascript_include_tag "i18n", "translations" %>

This `translations.js` file can be automatically generated by the `I18n::JS::Middleware`.
Just add it to your `config/application.rb` file.

    config.middleware.use I18n::JS::Middleware

If you can't generate this file in production (Heroku anyone?), you can "precompile"
it by running the following command. Move the middleware line to your
`config/environments/development.rb` file and run the following command before
deploying.

    $ rails runner I18n::JS.export

This will export all translation files, including the custom scopes you may have
defined on `config/i18n-js.yml`.

#### Vanilla JavaScript

Just add the `i18n.js` file to your page. You'll have to build the translations object
by hand or using your favorite programming language. More info below.

### Setting up

You **don't** need to set up a thing. The default settings will work just okay. But if you want to split translations into several files or specify specific contexts, you can follow the rest of this setting up section.

Set your locale is easy as

    I18n.defaultLocale = "pt-BR";
    I18n.locale = "pt-BR";
    I18n.currentLocale();
    // pt-BR

In practice, you'll have something like the following in your `application.html.erb`:

    <script type="text/javascript">
      I18n.defaultLocale = "<%= I18n.default_locale %>";
      I18n.locale = "<%= I18n.locale %>";
    </script>

You can use translate your messages:

    I18n.t("some.scoped.translation");
    // or translate with explicite setting of locale
    I18n.t("some.scoped.translation", {locale: "fr"});

You can also interpolate values:

    I18n.t("hello", {name: "John Doe"});

You can set default values for missing scopes:

    // simple translation
    I18n.t("some.missing.scope", {defaultValue: "A default message"});

    // with interpolation
    I18n.t("noun", {defaultValue: "I'm a {{noun}}", noun: "Mac"});

Translation fallback can be enabled by enabling the `I18n.fallbacks` option:

    <script type="text/javascript">
      I18n.fallbacks = true;
    </script>

By default missing translations will first be looked for in less
specific versions of the requested locale and if that fails by taking
them from your `I18n.defaultLocale`.

    // if I18n.defaultLocale = "en" and translation doesn't exist
    // for I18n.locale = "de-DE" this key will be taken from "de" locale scope
    // or, if that also doesn't exist, from "en" locale scope
    I18n.t("some.missing.scope");

Custom fallback rules can also be specified for a particular language. There
are three different ways of doing it so:

    I18n.locales.no = ["nb", "en"];
    I18n.locales.no = "nb";
    I18n.locales.no = function(locale){ return ["nb"]; };

Pluralization is possible as well and by default provides english rules:

    I18n.t("inbox.counting", {count: 10}); // You have 10 messages

The sample above expects the following translation:

    en:
      inbox:
        counting:
          one: You have 1 new message
          other: You have {{count}} new messages
          zero: You have no messages

**NOTE:** Rais I18n recognizes the `zero` option.

If you need special rules just define them for your language, for example Russian, just add a new pluralizer:

    I18n.pluralization["ru"] = function (count) {
      return count % 10 == 1 && count % 100 != 11 ? "one" : [2, 3, 4].indexOf(count % 10) >= 0 && [12, 13, 14].indexOf(count % 100) < 0 ? "few" : count % 10 == 0 || [5, 6, 7, 8, 9].indexOf(count % 10) >= 0 || [11, 12, 13, 14].indexOf(count % 100) >= 0 ? "many" : "other";
    };

You can find all rules on <http://unicode.org/repos/cldr-tmp/trunk/diff/supplemental/language_plural_rules.html>.

If you're using the same scope over and over again, you may use the `scope` option.

    var options = {scope: "activerecord.attributes.user"};

    I18n.t("name", options);
    I18n.t("email", options);
    I18n.t("username", options);

You also provide an array as scope.

    // use the greetings.hello scope
    I18n.t(["greetings", "hello"]);

#### Number formatting

Similar to Rails helpers, you have localized number and currency formatting.

    I18n.l("currency", 1990.99);
    // $1,990.99

    I18n.l("number", 1990.99);
    // 1,990.99

    I18n.l("percentage", 123.45);
    // 123.450%

To have more control over number formatting, you can use the
`I18n.toNumber`, `I18n.toPercentage`, `I18n.toCurrency` and `I18n.toHumanSize`
functions.

    I18n.toNumber(1000);     // 1,000.000
    I18n.toCurrency(1000);   // $1,000.00
    I18n.toPercentage(100);  // 100.000%

The `toNumber` and `toPercentage` functions accept the following options:

- `precision`: defaults to `3`
- `separator`: defaults to `.`
- `delimiter`: defaults to `,`
- `strip_insignificant_zeros`: defaults to `false`

See some number formatting examples:

    I18n.toNumber(1000, {precision: 0});                   // 1,000
    I18n.toNumber(1000, {delimiter: ".", separator: ","}); // 1.000,000
    I18n.toNumber(1000, {delimiter: ".", precision: 0});   // 1.000

The `toCurrency` function accepts the following options:

- `precision`: sets the level of precision
- `separator`: sets the separator between the units
- `delimiter`: sets the thousands delimiter
- `format`: sets the format of the output string
- `unit`: sets the denomination of the currency
- `strip_insignificant_zeros`: defaults to `false`

You can provide only the options you want to override:

    I18n.toCurrency(1000, {precision: 0}); // $1,000

The `toHumanSize` function accepts the following options:

- `precision`: defaults to `1`
- `separator`: defaults to `.`
- `delimiter`: defaults to `""`
- `strip_insignificant_zeros`: defaults to `false`
- `format`: defaults to `%n%u`

<!---->

    I18n.toHumanSize(1234); // 1KB
    I18n.toHumanSize(1234 * 1024); // 1MB

#### Date formatting

    // accepted formats
    I18n.l("date.formats.short", "2009-09-18");           // yyyy-mm-dd
    I18n.l("time.formats.short", "2009-09-18 23:12:43");  // yyyy-mm-dd hh:mm:ss
    I18n.l("time.formats.short", "2009-11-09T18:10:34");  // JSON format with local Timezone (part of ISO-8601)
    I18n.l("time.formats.short", "2009-11-09T18:10:34Z"); // JSON format in UTC (part of ISO-8601)
    I18n.l("date.formats.short", 1251862029000);          // Epoch time
    I18n.l("date.formats.short", "09/18/2009");           // mm/dd/yyyy
    I18n.l("date.formats.short", (new Date()));           // Date object

If you prefer, you can use the `I18n.strftime` function to format dates.

    var date = new Date();
    I18n.strftime(date, "%d/%m/%Y");

The accepted formats are:

    %a  - The abbreviated weekday name (Sun)
    %A  - The full weekday name (Sunday)
    %b  - The abbreviated month name (Jan)
    %B  - The full month name (January)
    %c  - The preferred local date and time representation
    %d  - Day of the month (01..31)
    %-d - Day of the month (1..31)
    %H  - Hour of the day, 24-hour clock (00..23)
    %-H - Hour of the day, 24-hour clock (0..23)
    %I  - Hour of the day, 12-hour clock (01..12)
    %-I - Hour of the day, 12-hour clock (1..12)
    %m  - Month of the year (01..12)
    %-m - Month of the year (1..12)
    %M  - Minute of the hour (00..59)
    %-M - Minute of the hour (0..59)
    %p  - Meridian indicator (AM  or  PM)
    %S  - Second of the minute (00..60)
    %-S - Second of the minute (0..60)
    %w  - Day of the week (Sunday is 0, 0..6)
    %y  - Year without a century (00..99)
    %-y - Year without a century (0..99)
    %Y  - Year with century
    %z  - Timezone offset (+0545)

Check out `spec/*.spec.js` files for more examples!

## Using I18n.js with other languages (Python, PHP, ...)

The JavaScript library is language agnostic; so you can use it with PHP, Python, [you favorite language here].
The only requirement is that you need to set the `translations` attribute like following:

    I18n.translations = {};

    I18n.translations["en"] = {
      message: "Some special message for you"
    }

    I18n.translations["pt-BR"] = {
      message: "Uma mensagem especial para você"
    }

## Maintainer

- Nando Vieira - <http://nandovieira.com.br>

## Contributing

Once you've made your great commits:

1. [Fork](http://help.github.com/forking/) I18n.js
2. Create a topic branch - `git checkout -b my_branch`
3. Push to your branch - `git push origin my_branch`
4. [Create an Issue](http://github.com/fnando/i18n-js/issues) with a link to your branch
5. That's it!

Please respect the indentation rules and code style.
And use 2 spaces, not tabs. And don't touch the versioning thing.

## Running tests

You can run I18n tests using Node.js or your browser.

To use Node.js, execute the following command from the lib's root directory:

    $ ./node_modules/.bin/jasmine-node spec/js

To run using your browser, just open the `spec/js/specs.html` file.

## License

(The MIT License)

Permission is hereby granted, free of charge, to any person obtaining
a copy of this software and associated documentation files (the
'Software'), to deal in the Software without restriction, including
without limitation the rights to use, copy, modify, merge, publish,
distribute, sublicense, and/or sell copies of the Software, and to
permit persons to whom the Software is furnished to do so, subject to
the following conditions:

The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.