cmlenz@369: /**
cmlenz@369:  * Babel JavaScript Support
cmlenz@369:  *
cmlenz@369:  * Copyright (C) 2008 Edgewall Software
cmlenz@369:  * All rights reserved.
cmlenz@369:  *
cmlenz@369:  * This software is licensed as described in the file COPYING, which
cmlenz@369:  * you should have received as part of this distribution. The terms
cmlenz@369:  * are also available at http://babel.edgewall.org/wiki/License.
cmlenz@369:  *
cmlenz@369:  * This software consists of voluntary contributions made by many
cmlenz@369:  * individuals. For the exact contribution history, see the revision
cmlenz@369:  * history and logs, available at http://babel.edgewall.org/log/.
cmlenz@369:  */
cmlenz@369: 
cmlenz@369: /**
cmlenz@369:  * A simple module that provides a gettext like translation interface.
cmlenz@369:  * The catalog passed to load() must be a object conforming to this
cmlenz@369:  * interface::
cmlenz@369:  *
cmlenz@369:  *    {
cmlenz@369:  *      messages:     an object of {msgid: translations} items where
cmlenz@369:  *                    translations is an array of messages or a single
cmlenz@369:  *                    string if the message is not pluralizable.
cmlenz@369:  *      plural_expr:  the plural expression for the language.
cmlenz@369:  *      locale:       the identifier for this locale.
cmlenz@369:  *      domain:       the name of the domain.
cmlenz@369:  *    }
cmlenz@369:  *
cmlenz@369:  * Missing elements in the object are ignored.
cmlenz@369:  *
cmlenz@369:  * Typical usage::
cmlenz@369:  *
cmlenz@369:  *    var translations = babel.Translations.load(...).install();
cmlenz@369:  */
cmlenz@369: var babel = new function() {
cmlenz@369: 
cmlenz@369:   var defaultPluralExpr = function(n) { return n == 1 ? 0 : 1; };
cmlenz@369:   var formatRegex = /%?%(?:\(([^\)]+)\))?([disr])/g;
cmlenz@369: 
cmlenz@369:   /**
cmlenz@369:    * A translations object implementing the gettext interface
cmlenz@369:    */
cmlenz@369:   var Translations = this.Translations = function(locale, domain) {
cmlenz@369:     this.messages = {};
cmlenz@369:     this.locale = locale || 'unknown';
cmlenz@369:     this.domain = domain || 'messages';
cmlenz@369:     this.pluralexpr = defaultPluralExpr;
cmlenz@369:   };
cmlenz@369: 
cmlenz@369:   /**
cmlenz@369:    * Create a new translations object from the catalog and return it.
cmlenz@369:    * See the babel-module comment for more details.
cmlenz@369:    */
cmlenz@369:   Translations.load = function(catalog) {
cmlenz@369:     var rv = new Translations();
cmlenz@369:     rv.load(catalog);
cmlenz@369:     return rv;
cmlenz@369:   };
cmlenz@369: 
cmlenz@369:   Translations.prototype = {
cmlenz@369:     /**
cmlenz@369:      * translate a single string.
cmlenz@369:      */
cmlenz@369:     gettext: function(string) {
cmlenz@369:       var translated = this.messages[string];
cmlenz@369:       if (typeof translated == 'undefined')
cmlenz@369:         return string;
cmlenz@369:       return (typeof translated == 'string') ? translated : translated[0];
cmlenz@369:     },
cmlenz@369: 
cmlenz@369:     /**
cmlenz@369:      * translate a pluralizable string
cmlenz@369:      */
cmlenz@369:     ngettext: function(singular, plural, n) {
cmlenz@369:       var translated = this.messages[singular];
cmlenz@369:       if (typeof translated == 'undefined')
cmlenz@369:         return (n == 1) ? singular : plural;
cmlenz@369:       return translated[this.pluralexpr(n)];
cmlenz@369:     },
cmlenz@369: 
cmlenz@369:     /**
cmlenz@369:      * Install this translation document wide.  After this call, there are
cmlenz@369:      * three new methods on the window object: _, gettext and ngettext
cmlenz@369:      */
cmlenz@369:     install: function() {
cmlenz@369:       var self = this;
cmlenz@369:       window._ = window.gettext = function(string) {
cmlenz@369:         return self.gettext(string);
cmlenz@369:       };
cmlenz@369:       window.ngettext = function(singular, plural, n) {
cmlenz@369:         return self.ngettext(singular, plural, n);
cmlenz@369:       };
cmlenz@369:       return this;
cmlenz@369:     },
cmlenz@369: 
cmlenz@369:     /**
cmlenz@369:      * Works like Translations.load but updates the instance rather
cmlenz@369:      * then creating a new one.
cmlenz@369:      */
cmlenz@369:     load: function(catalog) {
cmlenz@369:       if (catalog.messages)
cmlenz@369:         this.update(catalog.messages)
cmlenz@369:       if (catalog.plural_expr)
cmlenz@369:         this.setPluralExpr(catalog.plural_expr);
cmlenz@369:       if (catalog.locale)
cmlenz@369:         this.locale = catalog.locale;
cmlenz@369:       if (catalog.domain)
cmlenz@369:         this.domain = catalog.domain;
cmlenz@369:       return this;
cmlenz@369:     },
cmlenz@369: 
cmlenz@369:     /**
cmlenz@369:      * Updates the translations with the object of messages.
cmlenz@369:      */
cmlenz@369:     update: function(mapping) {
cmlenz@369:       for (var key in mapping)
cmlenz@369:         if (mapping.hasOwnProperty(key))
cmlenz@369:           this.messages[key] = mapping[key];
cmlenz@369:       return this;
cmlenz@369:     },
cmlenz@369: 
cmlenz@369:     /**
cmlenz@369:      * Sets the plural expression
cmlenz@369:      */
cmlenz@369:     setPluralExpr: function(expr) {
cmlenz@369:       this.pluralexpr = new Function('n', 'return +(' + expr + ')');
cmlenz@369:       return this;
cmlenz@369:     }
cmlenz@369:   };
cmlenz@369: 
cmlenz@369:   /**
cmlenz@369:    * A python inspired string formatting function.  Supports named and
cmlenz@369:    * positional placeholders and "s", "d" and "i" as type characters
cmlenz@369:    * without any formatting specifications.
cmlenz@369:    *
cmlenz@369:    * Examples::
cmlenz@369:    *
cmlenz@369:    *    babel.format(_('Hello %s'), name)
cmlenz@369:    *    babel.format(_('Progress: %(percent)s%%'), {percent: 100})
cmlenz@369:    */ 
cmlenz@369:   this.format = function() {
cmlenz@369:     var arg, string = arguments[0], idx = 0;
cmlenz@369:     if (arguments.length == 1)
cmlenz@369:       return string;
cmlenz@369:     else if (arguments.length == 2 && typeof arguments[1] == 'object')
cmlenz@369:       arg = arguments[1];
cmlenz@369:     else {
cmlenz@369:       arg = [];
cmlenz@369:       for (var i = 1, n = arguments.length; i != n; ++i)
cmlenz@369:         arg[i - 1] = arguments[i];
cmlenz@369:     }
cmlenz@369:     return string.replace(formatRegex, function(all, name, type) {
cmlenz@369:       if (all[0] == all[1]) return all.substring(1);
cmlenz@369:       var value = arg[name || idx++];
cmlenz@369:       return (type == 'i' || type == 'd') ? +value : value; 
cmlenz@369:     });
cmlenz@369:   }
cmlenz@369: 
cmlenz@369: };