/* ***** BEGIN LICENSE BLOCK *****

  * Version: MPL 1.1/GPL 2.0/LGPL 2.1

  *

  * The contents of this file are subject to the Mozilla Public License Version

  * 1.1 (the "License"); you may not use this file except in compliance with

  * the License. You may obtain a copy of the License at

  * http://www.mozilla.org/MPL/

  *

  * Software distributed under the License is distributed on an "AS IS" basis,

  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License

  * for the specific language governing rights and limitations under the

  * License.

  *

  * The Original Code is Code modules: JavaScript array converter.

  *

  * The Initial Developer of the Original Code is

  * Alexander J. Vincent <ajvincent@gmail.com>.

  * Portions created by the Initial Developer are Copyright (C) 2007

  * the Initial Developer. All Rights Reserved.

  *

  * Contributor(s):

  *

  * Alternatively, the contents of this file may be used under the terms of

  * either the GNU General Public License Version 2 or later (the "GPL"), or

  * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),

  * in which case the provisions of the GPL or the LGPL are applicable instead

  * of those above. If you wish to allow use of your version of this file only

  * under the terms of either the GPL or the LGPL, and not to allow others to

  * use your version of this file under the terms of the MPL, indicate your

  * decision by deleting the provisions above and replace them with the notice

  * and other provisions required by the GPL or the LGPL. If you do not delete

  * the provisions above, a recipient may use your version of this file under

  * the terms of any one of the MPL, the GPL or the LGPL.

  *

  * ***** END LICENSE BLOCK ***** */

 /**

  * Utilities for JavaScript components loaded by the JS component

  * loader.

  *

  * Import into a JS component using

  * 'Components.utils.import("resource://app/modules/ArrayConverter.jsm");'

  *

  */

 EXPORTED_SYMBOLS = [ "ArrayConverter" ];

 debug("*** loading ArrayConverter\n");

 /**

  * Get a simple enumerator.

  *

  * @param aItemsList JavaScript array to enumerate.

  */

 function Enumerator(aItemsList) {

   this._itemsList = aItemsList;

   this._iteratorPosition = 0;

 }

 Enumerator.prototype = {

   // nsISimpleEnumerator

   hasMoreElements: function hasMoreElements() {

     return (this._iteratorPosition < this._itemsList.length);

   },

   // nsISimpleEnumerator

   getNext: function getNext() {

     if (!(this.hasMoreElements())) {

       throw Components.results.NS_ERROR_FAILURE;

     }

     var type = this._itemsList[this._iteratorPosition];

     this._iteratorPosition++;

     return type;

   },

   // nsISupports

   QueryInterface: function QueryInterface(aIID)

   {

     if (aIID.equals(Components.interfaces.nsISimpleEnumerator) ||

         aIID.equals(Components.interfaces.nsISupports))

       return this;

     throw Components.results.NS_ERROR_NO_INTERFACE;

   }

 }

 function NSArray(aItemsList) {

   this._itemsList = aItemsList;

 }

 NSArray.prototype = {

   // nsIArray

   get length() {

     return this._itemsList.length;

   },

   // nsIArray

   queryElementAt: function queryElementAt(aIndex, aIID) {

     if (aIndex > this.length - 1) {

       throw Components.results.NS_ERROR_ILLEGAL_VALUE;

     }

     return this._itemsList[aIndex].QueryInterface(aIID);

   },

   // nsIArray

   indexOf: function indexOf(aIndex, aElement) {

     for (var i = aIndex; i < this._itemsList.length; i++) {

       if (this._itemsList[i] == aElement) {

         return i;

       }

     }

     throw Components.results.NS_ERROR_NOT_FOUND;

   },

   // nsIArray

   enumerate: function enumerate() {

     return new Enumerator(this._itemsList);

   },

   // nsISupports

   QueryInterface: function QueryInterface(aIID)

   {

     if (aIID.equals(Components.interfaces.nsIArray) ||

         aIID.equals(Components.interfaces.nsISupports))

       return this;

     throw Components.results.NS_ERROR_NO_INTERFACE;

   }

 }

 var ArrayConverter = {

   /**

    * Get a JavaScript array for a nsIArray or nsISimpleEnumerator.

    *

    * @param aObject nsIArray or nsISimpleEnumerator to convert.

    *

    * @throws NS_ERROR_INVALID_ARG.

    */

   JSArray: function getJSArray(aObject) {

     if (aObject instanceof Components.interfaces.nsIArray) {

       aObject = aObject.enumerate();

     }

     if (!(aObject instanceof Components.interfaces.nsISimpleEnumerator)) {

       throw Components.results.NS_ERROR_INVALID_ARG;

     }

     var array = [];

     while (aObject.hasMoreElements()) {

       array[array.length] = aObject.getNext();

     }

     return array;

   },

   /**

    * Return a nsIArray for a JavaScript array.

    *

    * @param aArray JavaScript array to convert.

    */

   nsIArray: function get_nsIArray(aArray) {

     return new NSArray(aArray);

   },

   /**

    * Return a nsISimpleEnumerator for a JavaScript array.

    *

    * @param aArray JavaScript array to convert.

    */

   enumerator: function get_enumerator(/* in JSArray */ aArray) {

     return new Enumerator(aArray);

   },

   /**

    * Return a method to convert a JavaScript array into a XPCOM array.

    *

    * @param aArrayName Name of JavaScript array property in "this" to convert.

    */

   xpcomArrayMethod: function getXPCOMMethod(aArrayName) {

     /**

      * Return a XPCOM array and count.

      *

      * @param (out) aCount The length of the array returned.

      *

      * @return The XPCOM array.

      */

     return function xpcomArray(aCount) {

       var array = this[aArrayName];

       aCount.value = array.length;

       var rv = [];

       for (var i = 0; i < array.length; i++) {

         rv[i] = array[i];

       }

       return rv;

     }

   }

 };