/* eslint-disable no-tabs */
/*!
 * jQuery Internationalization library - Message Store
 *
 * Copyright (C) 2012 Santhosh Thottingal
 *
 * jquery.i18n is dual licensed GPLv2 or later and MIT. You don't have to do anything special to
 * choose one license or the other and you don't have to notify anyone which license you are using.
 * You are free to use UniversalLanguageSelector in commercial projects as long as the copyright
 * header is left intact. See files GPL-LICENSE and MIT-LICENSE for details.
 *
 * @licence GNU General Public Licence 2.0 or later
 * @licence MIT License
 */

(function ($)
{
  "use strict";

  var MessageStore = function ()
  {
    this.messages = {};
    this.sources = {};
  };

  function jsonMessageLoader(url)
  {
    var deferred = $.Deferred();

    $.getJSON(url)
      .done(deferred.resolve)
      .fail(function (jqxhr, settings, exception)
      {
        $.i18n.log("Error in loading messages from " + url + " Exception: " + exception);
        // Ignore 404 exception, because we are handling fallabacks explicitly
        deferred.resolve();
      });

    return deferred.promise();
  }

  /**
	 * See https://github.com/wikimedia/jquery.i18n/wiki/Specification#wiki-Message_File_Loading
	 */
  MessageStore.prototype = {

    /**
		 * General message loading API This can take a URL string for
		 * the json formatted messages.
		 * <code>load('path/to/all_localizations.json');</code>
		 *
		 * This can also load a localization file for a locale <code>
		 * load( 'path/to/de-messages.json', 'de' );
		 * </code>
		 * A data object containing message key- message translation mappings
		 * can also be passed Eg:
		 * <code>
		 * load( { 'hello' : 'Hello' }, optionalLocale );
		 * </code> If the data argument is
		 * null/undefined/false,
		 * all cached messages for the i18n instance will get reset.
		 *
		 * @param {string|Object} source
		 * @param {string} locale Language tag
		 * @return {jQuery.Promise}
		 */
    load: function (source, locale)
    {
      var key = null,
        deferreds = [],
        messageStore = this;

      if (typeof source === "string")
      {
        // This is a URL to the messages file.
        $.i18n.log("Loading messages from: " + source);
        return jsonMessageLoader(source)
          .then(function (localization)
          {
            return messageStore.load(localization, locale);
          });
      }

      if (locale)
      {
        // source is an key-value pair of messages for given locale
        messageStore.set(locale, source);

        return $.Deferred().resolve();
      }
      else
      {
        // source is a key-value pair of locales and their source
        for (key in source)
        {
          if (Object.prototype.hasOwnProperty.call(source, key))
          {
            locale = key;
            // No {locale} given, assume data is a group of languages,
            // call this function again for each language.
            deferreds.push(messageStore.load(source[key], locale));
          }
        }
        return $.when.apply($, deferreds);
      }
    },

    /**
		 * Set messages to the given locale.
		 * If locale exists, add messages to the locale.
		 *
		 * @param {string} locale
		 * @param {Object} messages
		 */
    set: function (locale, messages)
    {
      if (!this.messages[locale])
      {
        this.messages[locale] = messages;
      }
      else
      {
        this.messages[locale] = $.extend(this.messages[locale], messages);
      }
    },

    /**
		 *
		 * @param {string} locale
		 * @param {string} messageKey
		 * @return {boolean}
		 */
    get: function (locale, messageKey)
    {
      return this.messages[locale] && this.messages[locale][messageKey];
    }
  };

  $.extend($.i18n.messageStore, new MessageStore());
}(jQuery));