aronacher@364: /**
aronacher@364:  * Babel JavaScript Support
aronacher@364:  *
aronacher@364:  * Copyright (C) 2008 Edgewall Software
aronacher@364:  * All rights reserved.
aronacher@364:  *
aronacher@364:  * This software is licensed as described in the file COPYING, which
aronacher@364:  * you should have received as part of this distribution. The terms
aronacher@364:  * are also available at http://babel.edgewall.org/wiki/License.
aronacher@364:  *
aronacher@364:  * This software consists of voluntary contributions made by many
aronacher@364:  * individuals. For the exact contribution history, see the revision
aronacher@364:  * history and logs, available at http://babel.edgewall.org/log/.
aronacher@364:  */
aronacher@364: 
aronacher@364: /**
aronacher@364:  * A simple module that provides a gettext like translation interface.
aronacher@364:  * The catalog passed to load() must be a object conforming to this
aronacher@364:  * interface::
aronacher@364:  *
aronacher@364:  *    {
aronacher@364:  *      messages:     an object of {msgid: translations} items where
aronacher@364:  *                    translations is an array of messages or a single
aronacher@364:  *                    string if the message is not pluralizable.
aronacher@364:  *      plural_expr:  the plural expression for the language.
aronacher@364:  *      locale:       the identifier for this locale.
aronacher@364:  *      domain:       the name of the domain.
aronacher@364:  *    }
aronacher@364:  *
aronacher@364:  * Missing elements in the object are ignored.
aronacher@364:  *
aronacher@365:  * Typical usage::
aronacher@364:  *
aronacher@364:  *    var translations = babel.Translations.load(...).install();
aronacher@364:  */
aronacher@364: var babel = new function() {
aronacher@364: 
aronacher@364:   var defaultPluralExpr = function(n) { return n == 1 ? 0 : 1; };
aronacher@364:   var formatRegex = /%?%(?:\(([^\)]+)\))?([disr])/g;
aronacher@364: 
aronacher@364:   /**
aronacher@364:    * A translations object implementing the gettext interface
aronacher@364:    */
aronacher@364:   var Translations = this.Translations = function(locale, domain) {
aronacher@364:     this.messages = {};
aronacher@364:     this.locale = locale || 'unknown';
aronacher@364:     this.domain = domain || 'messages';
aronacher@364:     this.pluralexpr = defaultPluralExpr;
aronacher@364:   };
aronacher@364: 
aronacher@364:   /**
aronacher@364:    * Create a new translations object from the catalog and return it.
aronacher@364:    * See the babel-module comment for more details.
aronacher@364:    */
aronacher@364:   Translations.load = function(catalog) {
aronacher@364:     var rv = new Translations();
aronacher@364:     rv.load(catalog);
aronacher@364:     return rv;
aronacher@364:   };
aronacher@364: 
aronacher@364:   Translations.prototype = {
aronacher@364:     /**
aronacher@364:      * translate a single string.
aronacher@364:      */
aronacher@364:     gettext: function(string) {
aronacher@364:       var translated = this.messages[string];
aronacher@364:       if (typeof translated == 'undefined')
aronacher@364:         return string;
aronacher@364:       return (typeof translated == 'string') ? translated : translated[0];
aronacher@364:     },
aronacher@364: 
aronacher@364:     /**
aronacher@364:      * translate a pluralizable string
aronacher@364:      */
aronacher@364:     ngettext: function(singular, plural, n) {
aronacher@364:       var translated = this.messages[singular];
aronacher@364:       if (typeof translated == 'undefined')
aronacher@364:         return (n == 1) ? singular : plural;
aronacher@364:       return translated[this.pluralexpr(n)];
aronacher@364:     },
aronacher@364: 
aronacher@364:     /**
aronacher@364:      * Install this translation document wide.  After this call, there are
aronacher@364:      * three new methods on the window object: _, gettext and ngettext
aronacher@364:      */
aronacher@364:     install: function() {
aronacher@364:       var self = this;
aronacher@364:       window._ = window.gettext = function(string) {
aronacher@364:         return self.gettext(string);
aronacher@364:       };
aronacher@364:       window.ngettext = function(singular, plural, n) {
aronacher@364:         return self.ngettext(singular, plural, n);
aronacher@364:       };
aronacher@364:       return this;
aronacher@364:     },
aronacher@364: 
aronacher@364:     /**
aronacher@364:      * Works like Translations.load but updates the instance rather
aronacher@364:      * then creating a new one.
aronacher@364:      */
aronacher@364:     load: function(catalog) {
aronacher@364:       if (catalog.messages)
aronacher@364:         this.update(catalog.messages)
aronacher@364:       if (catalog.plural_expr)
aronacher@364:         this.setPluralExpr(catalog.plural_expr);
aronacher@364:       if (catalog.locale)
aronacher@364:         this.locale = catalog.locale;
aronacher@364:       if (catalog.domain)
aronacher@364:         this.domain = catalog.domain;
aronacher@364:       return this;
aronacher@364:     },
aronacher@364: 
aronacher@364:     /**
aronacher@364:      * Updates the translations with the object of messages.
aronacher@364:      */
aronacher@364:     update: function(mapping) {
aronacher@364:       for (var key in mapping)
aronacher@364:         if (mapping.hasOwnProperty(key))
aronacher@364:           this.messages[key] = mapping[key];
aronacher@364:       return this;
aronacher@364:     },
aronacher@364: 
aronacher@364:     /**
aronacher@364:      * Sets the plural expression
aronacher@364:      */
aronacher@364:     setPluralExpr: function(expr) {
aronacher@364:       this.pluralexpr = new Function('n', 'return +(' + expr + ')');
aronacher@364:       return this;
aronacher@364:     }
aronacher@364:   };
aronacher@364: 
aronacher@365:   /**
aronacher@365:    * A python inspired string formatting function.  Supports named and
aronacher@365:    * positional placeholders and "s", "d" and "i" as type characters
aronacher@365:    * without any formatting specifications.
aronacher@365:    *
aronacher@365:    * Examples::
aronacher@365:    *
aronacher@365:    *    babel.format(_('Hello %s'), name)
aronacher@365:    *    babel.format(_('Progress: %(percent)s%%'), {percent: 100})
aronacher@365:    */ 
aronacher@364:   this.format = function() {
aronacher@364:     var arg, string = arguments[0], idx = 0;
aronacher@364:     if (arguments.length == 1)
aronacher@364:       return string;
aronacher@364:     else if (arguments.length == 2 && typeof arguments[1] == 'object')
aronacher@364:       arg = arguments[1];
aronacher@364:     else {
aronacher@364:       arg = [];
aronacher@364:       for (var i = 1, n = arguments.length; i != n; ++i)
aronacher@364:         arg[i - 1] = arguments[i];
aronacher@364:     }
aronacher@364:     return string.replace(formatRegex, function(all, name, type) {
aronacher@364:       if (all[0] == all[1]) return all.substring(1);
aronacher@364:       var value = arg[name || idx++];
aronacher@364:       return (type == 'i' || type == 'd') ? +value : value; 
aronacher@364:     });
aronacher@364:   }
aronacher@364: 
aronacher@364: };