<?
/**
 * Global functions and constants for Metavid MediaWiki. 
 * 
 * All Metavid Wiki code is Released Under the GPL2
 * for more info visit http:/metavid.ucsc.edu/code
 * 
 */
define('MV_VERSION','0.1 (pre alpha)');

if ( !defined( 'MEDIAWIKI' ) )  die( 1 );
/**
 * Switch on Metavid MediaWiki. This function must be called in LocalSettings.php
 *  its separated out to allow for overwriting semantic wiki hooks and functions
 * if semantic wiki is enabled for this wiki. 
 */
 
//pre setup setup
if ( !function_exists( 'extAddSpecialPage' ) ) {
      require_once( dirname(__FILE__) . '/../ExtensionFunctions.php' );
}

$wgExtensionMessagesFiles['MetavidWiki'] =$mvgIP . '/languages/MV_Messages.php';
require_once($mvgIP . '/languages/MV_Language.php');


//setup autoload classes: 
$wgAutoloadClasses['MV_Overlay'] = dirname(__FILE__)  . '/MV_MetavidInterface/MV_Overlay.php';
$wgAutoloadClasses['MV_Component'] = dirname(__FILE__)  . '/MV_MetavidInterface/MV_Component.php';

$wgAutoloadClasses['MV_MetavidInterface']= dirname(__FILE__)  .'/MV_MetavidInterface/MV_MetavidInterface.php';
$wgAutoloadClasses['MV_SequencePlayer']= dirname(__FILE__)  .'/MV_MetavidInterface/MV_SequencePlayer.php';
$wgAutoloadClasses['MV_SequenceTools']= dirname(__FILE__)  .'/MV_MetavidInterface/MV_SequenceTools.php';
$wgAutoloadClasses['MV_SequenceTimeline']= dirname(__FILE__)  .'/MV_MetavidInterface/MV_SequenceTimeline.php';
$wgAutoloadClasses['MV_VideoPlayer']= dirname(__FILE__)  .'/MV_MetavidInterface/MV_VideoPlayer.php';
$wgAutoloadClasses['MV_Tools']= dirname(__FILE__)  .'/MV_MetavidInterface/MV_Tools.php';
$wgAutoloadClasses['MV_EditPageAjax'] = dirname(__FILE__)  .'/MV_MetavidInterface/MV_EditPageAjax.php';

$wgAutoloadClasses['MV_CategoryPage']= dirname(__FILE__)  .'/articlepages/MV_CategoryPage.php';
$wgAutoloadClasses['MV_SequencePage'] =  dirname(__FILE__)  .'/articlepages/MV_SequencePage.php';
$wgAutoloadClasses['MV_StreamPage'] = dirname(__FILE__)  .'/articlepages/MV_StreamPage.php';
$wgAutoloadClasses['MV_EditDataPage'] = $wgAutoloadClasses['MV_DataPage'] = 
	dirname(__FILE__) . '/articlepages/MV_DataPage.php';
$wgAutoloadClasses['MV_EditStreamPage']=dirname(__FILE__)  .'/MV_EditStreamPage.php';


$wgAutoloadClasses['MV_Title'] = dirname(__FILE__)  . '/MV_Title.php';
$wgAutoloadClasses['MV_Index'] = dirname(__FILE__)  . '/MV_Index.php';
$wgAutoloadClasses['MV_ImageGallery']=dirname(__FILE__) . '/MV_ImageGallery.php';
$wgAutoloadClasses['MV_Image'] = dirname(__FILE__)  . '/MV_Image.php';
$wgAutoloadClasses['MV_Stream'] =  dirname(__FILE__)  .'/MV_Stream.php';
$wgAutoloadClasses['MV_StreamFile']=dirname(__FILE__)  . '/MV_StreamFile.php';
$wgAutoloadClasses['MV_StreamImage'] = dirname(__FILE__)  . '/MV_StreamImage.php';
$wgAutoloadClasses['MV_ParserCache'] = dirname(__FILE__) . '/MV_ParserCache.php';
		
$markerList = array(); 

//override special search page: (requires ExtensionFunctions.php)
extAddSpecialPage( dirname(__FILE__) . '/specials/MV_SpecialMediaSearch.php', 'Search', 'MV_SpecialSearch' );

function enableMetavid() {	
	global $wgExtensionFunctions, $smwgNamespacesWithSemanticLinks;
	$wgExtensionFunctions[] = 'mvSetupExtension';	
	//add in metavid namespace to semanticLinks array: 
	$smwgNamespacesWithSemanticLinks[MV_NS_STREAM] = true;
	$smwgNamespacesWithSemanticLinks[MV_NS_STREAM_TALK] = false;
	$smwgNamespacesWithSemanticLinks[MV_NS_SEQUENCE] = true;
	$smwgNamespacesWithSemanticLinks[MV_NS_SEQUENCE_TALK] = false;  
	$smwgNamespacesWithSemanticLinks[MV_NS_MVD] = true;
	$smwgNamespacesWithSemanticLinks[MV_NS_MVD_TALK] = false;	
	return true;
}
function mvSetupExtension(){
	global $mvVersion, $mvNamespace, $mvgIP, $wgHooks, $wgExtensionCredits, $mvMasterStore, 
	$wgParser, $mvArticlePath, $mvgScriptPath, $wgServer, $wgExtensionFunctions,$markerList,
	$mvEnableAutoComplete, $mvEnableJSLinkBack, $mvEnableJSMVDrewrite;
	

	mvfInitMessages();
	//add header for autoComplete if enabled: 
	if($mvEnableAutoComplete || $mvEnableJSLinkBack || $mvEnableJSMVDrewrite ){
		mvfAutoAllPageHeader();
	}
	
	/**********************************************/
	/***** register special pages hooks       *****/
	/**********************************************/		
	//@@todo shift over to extAddSpecial page (to avoid loading every time)
	require_once( dirname(__FILE__) . '/specials/MV_SpecialCRUDStream.php');
	require_once( dirname(__FILE__) . '/specials/MV_SpecialListStreams.php');
	require_once( dirname(__FILE__) . '/specials/MV_SpecialExport.php');
	require_once( dirname(__FILE__) . '/specials/MV_SpecialMediaSearch.php');
	require_once( dirname(__FILE__) . '/specials/MV_SpecialMVAdmin.php');


	/**********************************************/
	/***** register hooks                     *****/
	/**********************************************/
	require_once($mvgIP . '/includes/MV_Hooks.php');
	//$wgHooks['ArticleSave'][] = 'mvSaveHook';
	$wgHooks['ArticleSaveComplete'][] = 'mvSaveHook';
	$wgHooks['ArticleDelete'][] = 'mvDeleteHook';
	$wgHooks['ArticleFromTitle'][] = 'mvDoMvPage';			
		
	$wgHooks['TitleMoveComplete'][]='mvMoveHook';
	$wgHooks['TitleisValidMove'][]='mvisValidMoveOperation';	
	
	$wgHooks['ParserAfterTidy'][]='mvParserAfterTidy';	
	
	$wgHooks['CustomEditor'][] = 'mvCustomEditor';
	$wgParser->setHook( 'sequence', 'mvSeqTag' );

	$wgHooks['BeforePageDisplay'][] = 'mvDoSpecialPage';
	
	
	/**********************************************/
	/***** credits (see "Special:Version")    *****/
	/**********************************************/
	$wgExtensionCredits['other'][] = array(
	    'name' => 'Metavid Wiki Extension',
	    'author' => 'Michael Dale',
	    'version' => 'alpha 0.1',
		'url' => 'http://metavid.org',
		'description' => 'Video Metadata Editor, Clip Sequencer and Media Search<br />' .
			'[http://metavid.ucsc.edu/wiki/index.php/MetaVidWiki_Software More about MetaVidWiki Software]'
	);
}	
/**********************************************/
/***** Header modifications               *****/
/**********************************************/
	/**
	 * header script to be added to all pages: 
	 * enables linkback and autocomplete for search
	 */
	function mvfAutoAllPageHeader(){
		global $mvgScriptPath, $wgJsMimeType, $wgOut;			
		/* (moved to on_dom ready)  but here as well*/ 
		$wgOut->addScript("<script type=\"{$wgJsMimeType}\" src=\"{$mvgScriptPath}/skins/mv_embed/jquery/jquery-1.2.1.js\"></script>");
		$wgOut->addScript("<script type=\"{$wgJsMimeType}\" src=\"{$mvgScriptPath}/skins/mv_embed/jquery/plugins/jquery.autocomplete.js\"></script>");
		$wgOut->addScript("<script type=\"{$wgJsMimeType}\" src=\"{$mvgScriptPath}/skins/mv_embed/jquery/plugins/jquery.hoverIntent.js\"></script>");
		
		$wgOut->addScript("<script type=\"{$wgJsMimeType}\" src=\"{$mvgScriptPath}/skins/mv_embed/mv_embed.js\"></script>");
		$wgOut->addScript("<script type=\"{$wgJsMimeType}\" src=\"{$mvgScriptPath}/skins/mv_allpages.js\"></script>");
		
		$mvCssUrl = $mvgScriptPath . '/skins/mv_custom.css';
		$wgOut->addLink(array(
				'rel'   => 'stylesheet',
				'type'  => 'text/css',
				'media' => 'all',
				'href'  => $mvCssUrl
		));								
	}
	/**
	*  This method is in charge of inserting additional CSS, JScript, and meta tags
	*  into the html header of each page.  It is called by pages 
	*  that will be embedding video or use metavid interfaces 
	* 
	* @@todo split up embed js & interface js include calls
	*
	*  $out is the modified OutputPage.
	*/		
	function mvfAddHTMLHeader($head_set='') {
		global $mvgHeadersInPlace; // record whether headers were created already (don't call mvfAddHTMLHeader twice)
		global $mvgArticleHeadersInPlace; // record whether article name specific headers are already there
		global $mvgScriptPath, $wgJsMimeType, $wgOut , $mvEnableAutoComplete, $mvEnableJSLinkBack, $mvEnableJSMVDrewrite;		
			
		if (!$mvgHeadersInPlace) {			
			//all sets use mv_common script: *not used much yet*  
			$wgOut->addScript("<script type=\"{$wgJsMimeType}\" src=\"{$mvgScriptPath}/skins/mv_common.js\"></script>");
					
			if($head_set=='smw_ext'|| $head_set=='search' || $head_set=='sequence' || $head_set=='stream_interface'||$head_set=='embed'){
				if(!($mvEnableAutoComplete || $mvEnableJSLinkBack ||$mvEnableJSMVDrewrite) ){
					$wgOut->addScript("<script type=\"{$wgJsMimeType}\" src=\"{$mvgScriptPath}/skins/mv_embed/mv_embed.js\"></script>");
				}
			}
			if($head_set=='search' || $head_set=='sequence'){	
				//get jquery and autocomplete for seq/search	
				//already included for all pages to support autoComplete 
				if(!($mvEnableAutoComplete || $mvEnableJSLinkBack ||$mvEnableJSMVDrewrite) ){
					$wgOut->addScript("<script type=\"{$wgJsMimeType}\" src=\"{$mvgScriptPath}/skins/mv_embed/jquery/jquery-1.2.1.js\"></script>");
					$wgOut->addScript("<script type=\"{$wgJsMimeType}\" src=\"{$mvgScriptPath}/skins/mv_embed/jquery/plugins/jquery.autocomplete.js\"></script>");								 
					$wgOut->addScript("<script type=\"{$wgJsMimeType}\" src=\"{$mvgScriptPath}/skins/mv_embed/jquery/plugins/jquery.hoverIntent.js\"></script>");
				}							
			}
			
			if($head_set=='search')
				$wgOut->addScript("<script type=\"{$wgJsMimeType}\" src=\"{$mvgScriptPath}/skins/mv_search.js\"></script>");	
			if($head_set=='sequence')
				$wgOut->addScript("<script type=\"{$wgJsMimeType}\" src=\"{$mvgScriptPath}/skins/mv_sequence.js\"></script>");
			if($head_set=='stream_interface')
				$wgOut->addScript("<script type=\"{$wgJsMimeType}\" src=\"{$mvgScriptPath}/skins/mv_stream.js\" ></script>");	
			//if($head_set=='smw_ext')
			//	$wgOut->addScript("<script type=\"{$wgJsMimeType}\" src=\"{$mvgScriptPath}/skins/mv_smw_ext.js\" ></script>");
			
			if(!($mvEnableAutoComplete || $mvEnableJSLinkBack) ){
				$mvCssUrl = $mvgScriptPath . '/skins/mv_custom.css';
				$wgOut->addLink(array(
					'rel'   => 'stylesheet',
					'type'  => 'text/css',
					'media' => 'all',
					'href'  => $mvCssUrl
				));				
			}
			//add extra IE styles fixes 
			$wgOut->addScript('<!--[if IE 7]>' .
								'<style type="text/css">@import "'.$mvgScriptPath . '/skins/mv_customIE6.css";</style>'.
							  '<![endif]--> ' .
							  '<!--[if IE 6]>'.
							  	'<style type="text/css">@import "'.$mvgScriptPath . '/skins/mv_customIE6.css";</style>'.
							  '<![endif]-->'
				);
			//add extra safari sheet
			$wgOut->addScript("<script type=\"{$wgJsMimeType}\">
if(navigator.userAgent.toLowerCase().indexOf('safari')!=-1){
	document.write('<style type=\"text/css\">@import \"{$mvgScriptPath}/skins/mv_customSafari.css\";</style>');	
}
</script>");
			//add in the semantic wiki css if in stream interface
			if($head_set=='stream_interface')
				$wgOut->addScript('<link rel="stylesheet" type="text/css" media="screen, projection" href="/mvWiki/extensions/SemanticMediaWiki/skins/SMW_custom.css" />');
			$mvgHeadersInPlace=true;
		}
		return true; // always return true, in order not to stop MW's hook processing!
	}
/**
 * Init the additional namepsaces used by Metavid MediaWiki. The
 * parameter denotes the least unused even namespace ID that is
 * greater or equal to 100.
 */
function mvInitNamespaces() {
	global $mvNamespaceIndex, $wgExtraNamespaces, $wgNamespacesWithSubpages, $wgLanguageCode, $mvgContLang,
		$mvLastNamespaceIndex;
		
	if (!isset($mvNamespaceIndex)) {
			$mvNamespaceIndex = 100;
	}

	//register the namespace:MVD & Metavid
	define('MV_NS_STREAM',			$mvNamespaceIndex);
	define('MV_NS_STREAM_TALK',		$mvNamespaceIndex+1);
	define('MV_NS_SEQUENCE',		$mvNamespaceIndex+2);
	define('MV_NS_SEQUENCE_TALK',	$mvNamespaceIndex+3);
	define('MV_NS_MVD', 			$mvNamespaceIndex+4);
	define('MV_NS_MVD_TALK', 		$mvNamespaceIndex+5);
	
	mvfInitContentLanguage($wgLanguageCode);
		
	//print_r($mvgContLang);
	//print_r($mvgContLang->getNamespaces());
	// Register namespace identifiers
	if (!is_array($wgExtraNamespaces)) { $wgExtraNamespaces=array(); }	
	$wgExtraNamespaces = $wgExtraNamespaces + $mvgContLang->getNamespaces();	
	//update the mvLastNamespaceIndex for however many name spaces are established above: 
	$mvLastNamespaceIndex =  $mvNamespaceIndex +6;
}

/**********************************************/
/***** language settings                  *****/
/**********************************************/

/**
 * Initialize a global language object for content language. This
 * must happen early on, even before user language is known, to
 * determine labels for additional namespaces. In contrast, messages
 * can be initialized much later when they are actually needed.
 */
function mvfInitContentLanguage($langcode) {
	global $mvgIP, $mvgContLang;

	if (!empty($mvgContLang)) { return; }

	$mvContLangClass = 'MV_Language' . str_replace( '-', '_', ucfirst( $langcode ) );

	if (file_exists($mvgIP . '/languages/'. $mvContLangClass . '.php')) {
		include_once( $mvgIP . '/languages/'. $mvContLangClass . '.php' );
		//print "included: " . $mvgIP . '/languages/'. $mvContLangClass . '.php';
	}

	// fallback if language not supported
	if ( !class_exists($mvContLangClass)) {
		include_once($mvgIP . '/languages/MV_LanguageEn.php');
		$mvContLangClass = 'MV_LanguageEn';
	}

	$mvgContLang = new $mvContLangClass();
}

/**
 * Initialize the global language object for user language. This
 * must happen after the content language was initialized, since
 * this language is used as a fallback.
 */
function mvfInitUserLanguage($langcode) {
	global $mvgIP, $mvgLang;

	if (!empty($mvgLang)) { return; }

	$mvLangClass = 'MV_Language' . str_replace( '-', '_', ucfirst( $langcode ) );

	if (file_exists($mvgIP . '/languages/'. $mvLangClass . '.php')) {
		include_once( $mvgIP . '/languages/'. $mvLangClass . '.php' );
	}
	// fallback if language not supported
	if ( !class_exists($mvLangClass)) {
		global $mvgContLang;
		$mvgLang = $mvgContLang;
	} else {
		$mvgLang = new $mvLangClass();
	}
}
/**
 * Initialize messages - these settings must be applied later on, since
 * the MessageCache does not exist yet when the settings are loaded in
 * LocalSettings.php.
 * Function based on version in ContributionScores extension
 */
function mvfInitMessages() {
	global $wgVersion, $wgExtensionFunctions;
	if (version_compare($wgVersion, '1.11', '>=' )) {
		wfLoadExtensionMessages( 'MetavidWiki' );
	} else {
		$wgExtensionFunctions[] = 'sffLoadMessagesManually';
	}
}

/**
 * Setting of message cache for versions of MediaWiki that do not support
 * wgExtensionFunctions - based on ceContributionScores() in
 * ContributionScores extension
 */
function sffLoadMessagesManually() {
	global $mvgIP, $wgMessageCache;

	# add messages
	require($mvgIP . '/languages/MV_Messages.php');
	global $messages;
	foreach($messages as $key => $value) {
		$wgMessageCache->addMessages($messages[$key], $key);
	}
}
/*
 * Ajax Hooks 
 */
$wgAjaxExportList[] = 'mv_auto_complete_all';
$wgAjaxExportList[] = 'mv_auto_complete_person';
$wgAjaxExportList[] = 'mv_auto_complete_stream_name';
$wgAjaxExportList[] = 'mv_disp_mvd';

$wgAjaxExportList[] = 'mv_add_disp';
$wgAjaxExportList[] = 'mv_remove_mvd';
$wgAjaxExportList[] = 'mv_disp_remove_mvd';

$wgAjaxExportList[] = 'mv_edit_disp';
$wgAjaxExportList[] = 'mv_edit_preview';
$wgAjaxExportList[] = 'mv_edit_submit';
$wgAjaxExportList[] = 'mv_edit_sequence_submit';
$wgAjaxExportList[] = 'mv_seqtool_disp';

$wgAjaxExportList[] = 'mv_history_disp';
$wgAjaxExportList[] = 'mv_adjust_disp';
$wgAjaxExportList[] = 'mv_adjust_submit';

//search interface exported functions: 
$wgAjaxExportList[] = 'mv_expand_wt';
$wgAjaxExportList[] = 'mv_submit_remove';
$wgAjaxExportList[] = 'mv_tool_disp';
$wgAjaxExportList[] = 'mv_date_obj';

//media serving 
$wgAjaxExportList[] = 'mv_frame_server';

/*
 * Utility functions:
 */
 
function php2jsObj($array, $objName='mv_result')
{
   return  $objName . ' = ' . phpArrayToJsObject_Recurse($array) . ";\n";
}
function PhpArrayToJsObject_Recurse($array){
   // Base case of recursion: when the passed value is not a PHP array, just output it (in quotes).
   if(! is_array($array) && !is_object($array) ){
       // Handle null specially: otherwise it becomes "".
       if ($array === null)
       {
           return 'null';
       }      
       return '"' . javascript_escape($array) . '"';
   }  
   // Open this JS object.
   $retVal = "{";
   // Output all key/value pairs as "$key" : $value
   // * Output a JS object (using recursion), if $value is a PHP array.
   // * Output the value in quotes, if $value is not an array (see above).
   $first = true;
   foreach($array as $key => $value){
       // Add a comma before all but the first pair.
       if (! $first ){
           $retVal .= ', ';
       }
       $first = false;      
       // Quote $key if it's a string.
       if (is_string($key) ){
           $key = '"' . $key . '"';
       }	         
       $retVal .= $key . ' : ' . PhpArrayToJsObject_Recurse($value);
   }   
   // Close and return the JS object.
   return $retVal . "}";
}
function javascript_escape($val){
	//first strip /r
	$val = str_replace("\r", '', $val);
	return str_replace(	array('"', "\n", '{', '}'), 
						array('\"', '"'."+\n".'"', '\{', '\}'),
						$val);	
}
 /*
  * Check if time is NTP based: hh:mm:ss.(fraction of a second)
  */
function mvIsNtpTime($time){
	//could alternatively do preg match: 
	//preg_match('/[0-9]+:[0-9][0-9]:[0-9][0-9]/', $this->start_time, $matches);
 	//if(count($matches)==0)	
	$tp = split(':',$time);
	if(count($tp)!=3)return false;
	list($hours, $min, $sec)=$tp;
	//min/sec should be no larger than 60 
	if($min>=60 || $sec>=60)return false;
	//@@TODO min & hour should not be a floating point number	
	if(is_numeric($hours) && is_numeric($min) && is_numeric($sec))
		return true;
	return false;
}
/*
 * takes ntp time of format hh:mm:ss and converts to seconds 
 */
function ntp2seconds($str_time){
	$time_ary = explode(':', $str_time);	
	$hours=$min=$sec=0;
	if(count($time_ary)==3){
		$hours=$time_ary[0];
		$min=$time_ary[1];
		$sec=$time_ary[2];
	}else if(count($time_ary)==2){
		$min=$time_ary[0];
		$sec=$time_ary[1];
	}else if(count($time_ary)==1){
		$sec=$time_ary[0];
	}
	
	return ($hours*3600) + ($min*60) + $sec;
}
/*
 * takes seconds duration and return hh:mm:ss time
 */
function seconds2ntp($seconds){
	$dur = time_duration_2array($seconds);
	//be sure to output leading zeros (for min,sec):  
	return sprintf("%d:%02d:%02d", $dur['hours'], $dur['minutes'], $dur['seconds']);
}
/*
 * converts seconds to time unit array
 */
function time_duration_2array ($seconds, $periods = null){        
	// Define time periods
	if (!is_array($periods)) {
		$periods = array (
			'years'     => 31556926,
			'months'    => 2629743,
			'weeks'     => 604800,
			'days'      => 86400,
			'hours'     => 3600,
			'minutes'   => 60,
			'seconds'   => 1
			);
	}

	// Loop
	$seconds = (float) $seconds;
	foreach ($periods as $period => $value) {
		$count = floor($seconds / $value);
		if ($count == 0) {
			//must include hours minutes and seconds even if they are 0
			if($period=='hours' || $period=='minutes' || $period=='seconds'){
				$values[$period] = 0;
			}
			continue;
		}
		$values[$period] = sprintf("%02d", $count);
		$seconds = $seconds % $value;
	}
	// Return
	if (empty($values)) {
		$values = null;
	}
	return $values;
}
/*
 * direct output for quick creation of non editable pages (errors, stream access etc)
 */
function mvOutputSpecialPage( $title, & $page ) {	
	global $wgOut, $wgTitle;
					
	//$wgTitle = SpecialPage::getTitleFor($title);
	$wgTitle->mNamespace = NS_SPECIAL;
		
	$wgOut->setPageTitle( $title );
	$wgOut->setHTMLTitle( $title );
	$wgOut->setArticleRelated( false );
	$wgOut->enableClientCache( true );

	$wgOut->addHTML( $page );
	$wgOut->returnToMain( false );
	
	$wgOut->output();
	
	exit();
}
function mvDoMetavidStreamPage(&$title, &$article){
	$mvTitle = new MV_Title( $title->mDbkeyform); 	
	if($mvTitle->doesStreamExist()){				
		//@@TODO check if we have /name corresponding to a view or
		// /ss:ss:ss or /ss:ss:ss/ee:ee:ee corresponding to a time request
		//force metavid to be special 
		//(@@todo clean up skin.php to enable better tab controls)
		//$title->mNamespace= NS_SPECIAL;
		
		//@@todo check if the requested title is already just the stream name:		 	
		$streamTitle = Title::newFromText( $mvTitle->getStreamName(), MV_NS_STREAM);
		//print " new title: " . $streamTitle . "\n";		
		$article = new MV_StreamPage($streamTitle, $mvTitle);
	}else{				
		mvMissingStreamPage($mvTitle->stream_name);
	}	
}
/*
 * global MV_Stream server
 * @@todo cache this function
 */  
function mvGetMVStream($stream_init){
	global $MVStreams;	
	//wfDebug('mv get stream: ' .$stream_name . "\n");
	if (is_object($stream_init)){
		$stream_init = get_object_vars($stream_init);
	}else if (is_string($stream_init)){
		//if a string is passed in assume its the stream name: 
		$stream_init=array('name'=>$stream_init);
	}
	if(isset($stream_init['name'])){
		$stream_name=$stream_init['name'];
	}else if(isset($stream_init['id'])){
		$stream_name = MV_Stream::getStreamNameFromId($stream_init['id']);
	}else{
		die('error no id or name in init');
	}
	
	//@@todo cache in memcache)	
	if(!isset($MVStreams[$stream_name])){
		$MVStreams[$stream_name] = new MV_Stream($stream_init);
		$MVStreams[$stream_name]->db_load_stream();
	}	
	return $MVStreams[$stream_name];
}

function mvGetMVTitle(){
	
}
function mvViewPrevNext( $offset, $limit, $link, $query = '', $atend = false ) {
	global $wgLang;
	$fmtLimit = $wgLang->formatNum( $limit );
	$prev = wfMsg( 'prevn', $fmtLimit );
	$next = wfMsg( 'nextn', $fmtLimit );

	if( is_object( $link ) ) {
		$title =& $link;
	} else {
		$title = Title::newFromText( $link );
		if( is_null( $title ) ) {
			return false;
		}
	}

	if ( 0 != $offset ) {
		$po = $offset - $limit;
		if ( $po < 0 ) { $po = 0; }
		$q = "limit={$limit}&offset={$po}";
		if ( '' != $query ) { $q .= '&'.$query; }
		$plink = '<a href="' . $title->escapeLocalUrl( $q ) . "\" class=\"mw-prevlink\">{$prev}</a>";
	} else { $plink = $prev; }

	$no = $offset + $limit;
	$q = 'limit='.$limit.'&offset='.$no;
	if ( '' != $query ) { $q .= '&'.$query; }

	if ( $atend ) {
		$nlink = $next;
	} else {
		$nlink = '<a href="' . $title->escapeLocalUrl( $q ) . "\" class=\"mw-nextlink\">{$next}</a>";
	}
	$nums = wfNumLink( $offset, 20, $title, $query ) . ' | ' .
	  wfNumLink( $offset, 50, $title, $query ) . ' | ' .
	  wfNumLink( $offset, 100, $title, $query ) ;	  
	return wfMsg( 'viewprevnext', $plink, $nlink, $nums );
}
?>