/**

 * This file implements general Javascript functions.

 *

 * This file is part of the evoCore framework - {@link http://evocore.net/}

 * See also {@link http://sourceforge.net/projects/evocms/}.

 *

 * @copyright (c)2003-2006 by Francois PLANQUE - {@link http://fplanque.net/}

 * Parts of this file are copyright (c)2004-2006 by Daniel HAHLER - {@link http://thequod.de/contact}.

 *

 * {@internal License choice

 * - If you have received this file as part of a package, please find the license.txt file in

 *   the same folder or the closest folder above for complete license terms.

 * - If you have received this file individually (e-g: from http://evocms.cvs.sourceforge.net/)

 *   then you must choose one of the following licenses before using the file:

 *   - GNU General Public License 2 (GPL) - http://www.opensource.org/licenses/gpl-license.php

 *   - Mozilla Public License 1.1 (MPL) - http://www.opensource.org/licenses/mozilla1.1.php

 * }}

 *

 * {@internal Open Source relicensing agreement:

 * Daniel HAHLER grants Francois PLANQUE the right to license

 * Daniel HAHLER's contributions to this file and the b2evolution project

 * under any OSI approved OSS license (http://www.opensource.org/licenses/).

 * }}

 *

 * @package main

 *

 * {@internal Below is a list of authors who have contributed to design/coding of this file: }}

 * @author blueyed: Daniel HAHLER

 * @author fplanque: Francois PLANQUE

 *

 * @version $Id: functions.js,v 1.30 2007/09/16 22:06:37 fplanque Exp $

 */





/**

 * Cross browser event handling for IE5+, NS6+ an Mozilla/Gecko

 * @author Scott Andrew

 */

function addEvent( elm, evType, fn, useCapture )

{

	if( elm.addEventListener )

	{ // Standard & Mozilla way:

		elm.addEventListener( evType, fn, useCapture );

		return true;

	}

	else if( elm.attachEvent )

	{ // IE way:

		var r = elm.attachEvent( 'on'+evType, fn );

		return r;

	}

	else

	{ // "dirty" way (IE Mac for example):

		// Will overwrite any previous handler! :((

		elm['on'+evType] = fn;

		return false;

	}

}





/**

 * Browser status changed. 

 * Warning: This is disabled in modern browsers.

 */

function setstatus( message )

{

	window.status = message;

	return true;

}

function resetstatus()

{

	window.status = 'Done';

}



/**

 * Opens a window, centers it and makes sure it gets focus.

 */

function pop_up_window( href, target, width, height, params )

{

 	if( typeof(width) == 'undefined' )

 	{

		width = 750;

	}



 	if( typeof(height) == 'undefined' )

 	{

		height = 550;

	}



	var left = (screen.width - width) / 2;

	var top = (screen.height - height) / 2;



 	if( typeof(params) == 'undefined' )

	{

		params = 'scrollbars=yes, status=yes, resizable=yes, menubar=yes';

	}



	params = 'width=' + width + ', height=' + height + ', ' + 'left=' + left + ', top=' + top + ', ' + params;



	// Open window:

	opened = window.open( href, target, params );



	// Bring to front!

	opened.focus();



	if( typeof(openedWindows) == 'undefined' )

	{

		openedWindows = new Array(opened);

	}

	else

	{

		openedWindows.push(opened);

	}



	// Tell the caller there is no need to process href="" :

	return false;

}





/**

 * Shows/Hides target_id, and updates text_id object with either

 * text_when_displayed or text_when_hidden.

 *

 * It simply uses the value of the elements display attribute and toggles it.

 *

 * @return false

 */

function toggle_display_by_id( text_id, target_id, text_when_displayed, text_when_hidden )

{

	if( document.getElementById(target_id).style.display=="" )

	{

		document.getElementById( text_id ).innerHTML = text_when_hidden;

		document.getElementById( target_id ).style.display="none";

	}

	else

	{

		document.getElementById( text_id ).innerHTML = text_when_displayed;

		document.getElementById( target_id ).style.display="";

	}

	return false;

}





/**

 * Open or close a clickopen area (by use of CSS style).

 *

 * You have to define a div with id clickdiv_<ID> and a img with clickimg_<ID>,

 * where <ID> is the first param to the function.

 *

 * @param string html id of the element to toggle

 * @param string CSS display property to use when visible ('inline', 'block')

 * @return false

 */

function toggle_clickopen( id, hide, displayVisible )

{

	if( !( clickdiv = document.getElementById( 'clickdiv_'+id ) )

			|| !( clickimg = document.getElementById( 'clickimg_'+id ) ) )

	{

		alert( 'ID '+id+' not found!' );

		return false;

	}



	if( typeof(hide) == 'undefined' )

	{

		hide = document.getElementById( 'clickdiv_'+id ).style.display != 'none';

	}



	if( typeof(displayVisible) == 'undefined' )

	{

		displayVisible = ''; // setting it to "empty" is the default for an element's display CSS attribute

	}



	if( hide )

	{

		clickdiv.style.display = 'none';

		clickimg.src = imgpath_expand;



		return false;

	}

	else

	{

		clickdiv.style.display = displayVisible;

		clickimg.src = imgpath_collapse;



		return false;

	}

}





// deprecated but left for old plugins:

function textarea_replace_selection( myField, snippet, target_document )

{

	textarea_wrap_selection( myField, snippet, '', 1, target_document );

}



/**

 * Textarea insertion code.

 *

 * @var element

 * @var text

 * @var text

 * @var boolean

 * @var document (needs only be passed from a popup window as window.opener.document)

 */

function textarea_wrap_selection( myField, before, after, replace, target_document )

{

	target_document = target_document || document;



	var hook_params = {

		'element': myField,

		'before': before,

		'after': after,

		'replace': replace,

		'target_document': target_document

	};



	// First try, if a JavaScript callback is registered to handle this.

	// E.g. the tinymce_plugin uses registers "wrap_selection_for_itemform_post_content"

	//      to replace the (non-)selection

	if( b2evo_Callbacks.trigger_callback( "wrap_selection_for_"+myField.id, hook_params ) )

	{

		return;

	}

	if( window.opener

		&& window.opener.b2evo_Callbacks

		&& ( typeof window.opener.b2evo_Callbacks != "undefined" ) )

	{ // callback in parent document (e.g. "Files" popup)

		if( window.opener.b2evo_Callbacks.trigger_callback( "wrap_selection_for_"+myField.id, hook_params ) )

		{

			return;

		}

	}



	// Basic handling:

	if(target_document.selection)

	{ // IE support:

		myField.focus();

		sel = target_document.selection.createRange();

		if( replace )

		{

			sel.text = before + after;

		}

		else

		{

			sel.text = before + sel.text + after;

		}

		myField.focus();

	}

	else if (myField.selectionStart || myField.selectionStart == '0')

	{ // MOZILLA/NETSCAPE support:

		var startPos = myField.selectionStart;

		var endPos = myField.selectionEnd;

		var cursorPos;



		var scrollTop, scrollLeft;

		if( myField.type == 'textarea' && typeof myField.scrollTop != 'undefined' )

		{ // remember old position

			scrollTop = myField.scrollTop;

			scrollLeft = myField.scrollLeft;

		}



		if( replace )

		{

			myField.value = myField.value.substring( 0, startPos)

				+ before

				+ after

				+ myField.value.substring( endPos, myField.value.length);

			cursorPos = startPos + before.length + after.length;

		}

		else

		{

			myField.value = myField.value.substring( 0, startPos)

				+ before

				+ myField.value.substring(startPos, endPos)

				+ after

				+ myField.value.substring( endPos, myField.value.length);

			cursorPos = endPos + before.length + after.length;

		}



		if( typeof scrollTop != 'undefined' )

		{ // scroll to old position

			myField.scrollTop = scrollTop;

			myField.scrollLeft = scrollLeft;

		}



		myField.focus();

		myField.selectionStart = cursorPos;

		myField.selectionEnd = cursorPos;

	}

	else

	{ // Default browser support:

		myField.value += before + after;

		myField.focus();

	}

}



/**

 * Open or close a filter area (by use of CSS style).

 *

 * You have to define a div with id clickdiv_<ID> and a img with clickimg_<ID>,

 * where <ID> is the first param to the function.

 *

 * @param string html id of the element to toggle

 * @return false

 */

function toggle_filter_area( filter_name )

{

	// Find objects to toggle:

	if( !( clickdiv = document.getElementById( 'clickdiv_'+filter_name ) )

			|| !( clickimg = document.getElementById( 'clickimg_'+filter_name ) ) )

	{

		alert( 'ID '+filter_name+' not found!' );

		return false;

	}



	// Determine if we want to show or to hide (based on current state).

	hide = document.getElementById( 'clickdiv_'+filter_name ).style.display != 'none';



	if( hide )

	{	// Hide/collapse filters:

		clickdiv.style.display = 'none';

		clickimg.src = imgpath_expand;

		asyncRequest( htsrv_url+'async.php?collapse='+filter_name );

	}

	else

	{	// Show/expand filters

		clickdiv.style.display = 'block';

		clickimg.src = imgpath_collapse;

		asyncRequest( htsrv_url+'async.php?expand='+filter_name );

	}



	return false;

}





/**

 * "AJAX" wrapper

 *

 * What this really is actually, is just a function to perform an asynchronous Request to the server.

 * There is no need to have any XML involved.

 *

 * @param string url urlencoded

 */

function asyncRequest( url )

{

	if (window.XMLHttpRequest)

	{ // browser has native support for XMLHttpRequest object

		req = new XMLHttpRequest();

	}

	else if (window.ActiveXObject)

	{ // try XMLHTTP ActiveX (Internet Explorer) version

		req = new ActiveXObject("Microsoft.XMLHTTP");

	}



	if(req)

	{

		swapSection( '...' );

		//req.onreadystatechange = responseHandler;

    req.onreadystatechange = asyncResponseHandler;

		req.open( 'GET', url, true );

		req.setRequestHeader("content-type","application/x-www-form-urlencoded");

		req.send('dummy');

	}

	else

	{

		swapSection('Your browser does not seem to support XMLHttpRequest.');

	}



	return false;

}



function asyncResponseHandler()

{

	if( req.readyState == 4 )

	{	// Request has been loaded (readyState = 4)

		if( req.status == 200 )

		{	// Status is 200 OK:

			swapSection( req.responseText );

		}

		else

		{

			swapSection("There was a problem retrieving the XML data:\n" + req.statusText);

		}

	}

}



function swapSection( data )

{

	var swappableSection = document.getElementById('asyncResponse');

	if( swappableSection )

	{

		swappableSection.innerHTML = data;

	}

}





/*

 * Javascript callback handling, for helping plugins to interact in Javascript.

 *

 * This is, so one plugin (e.g. the tinymce_plugin) can say that it handles insertion of raw

 * content into a specific element ("itemform_post_content" in this case):

 *

 * <code>

 * if( typeof b2evo_Callbacks == "object" )

 * { // add a callback, that lets us insert the

 *   b2evo_Callbacks.register_callback( "insert_raw_into_itemform_post_content", function(value) {

 *       tinyMCE.execCommand( "mceInsertRawHTML", false, value );

 *       return true;

 *     } );

 * }

 * </code>

 *

 * and others (e.g. the smilies_plugin or the youtube_plugin) should first try to use this

 * callback to insert the HTML:

 *

 * if( typeof b2evo_Callbacks == 'object' )

 * { // see if there's a callback registered that should handle this:

 *   if( b2evo_Callbacks.trigger_callback("insert_raw_into_"+b2evoCanvas.id, tag) )

 *   {

 *     return;

 *   }

 * }

 */

function b2evo_Callbacks() {

	this.eventHandlers = new Array();

};



b2evo_Callbacks.prototype = {

	register_callback : function(event, f) {

		if( typeof this.eventHandlers[event] == "undefined" )

		{

			this.eventHandlers[event] = new Array();

		}

		this.eventHandlers[event][this.eventHandlers[event].length] = f;

	},



	/**

	 * @param String event name

	 * @param mixed argument1

	 * @param mixed argument2

	 * ...

	 * @return boolean true, if any callback returned true

	 *                 null, if no callback registered

	 */

	trigger_callback : function(event, args) {



		if( typeof this.eventHandlers[event] == "undefined" )

		{

			return null;

		}



		var r = false;



		// copy arguments and build function param string for eval():

		var cb_args = '';

		var cb_arguments = arguments;

		for( var i = 1; i < arguments.length; i++ ) {

			cb_args += "cb_arguments[" + i + "], ";

		}

		if( cb_args.length )

		{ // remove last ", ":

			cb_args = cb_args.substring( 0, cb_args.length - 2 );

		}



		// eval() for each registered callback:

		for( var i = 0; i < this.eventHandlers[event].length; i++ )

		{

			var f = this.eventHandlers[event][i];

			r = eval( "f("+cb_args+");" ) || r;

		}



		return r;

	}

};



var b2evo_Callbacks = new b2evo_Callbacks();



/*

 * $Log: functions.js,v $

 * Revision 1.30  2007/09/16 22:06:37  fplanque

 * minor

 *

 * Revision 1.29  2007/06/30 21:05:17  fplanque

 * fixed for FF; I hope.

 *

 * Revision 1.28  2007/06/29 23:42:30  blueyed

 * - Fixed b2evoCallback in textarea_wrap_selection: uses "wrap_selection_for_" callback now instead of "insert_raw_into_"

 * - trigger_callback now returns null if no callback is registered

 *

 * Revision 1.27  2007/04/20 01:42:32  fplanque

 * removed excess javascript

 *

 * Revision 1.26  2007/03/07 19:26:20  blueyed

 * Fix; for IE IIRC

 *

 * Revision 1.25  2007/01/26 02:12:09  fplanque

 * cleaner popup windows

 *

 * Revision 1.24  2006/12/10 03:05:02  blueyed

 * cleanup

 *

 * Revision 1.23  2006/11/28 19:44:51  blueyed

 * b2evo_Callbacks.trigger_callback() now supports variable number of arguments; textarea_replace_selection(): default to document for target_document arg

 *

 * Revision 1.22  2006/11/26 01:42:10  fplanque

 * doc

 *

 */