<?php
/*
 * $RCSfile: GalleryTemplateAdapter.class,v $
 *
 * Gallery - a web based photo album viewer and editor
 * Copyright (C) 2000-2005 Bharat Mediratta
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or (at
 * your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA  02110-1301, USA.
 */
/**
 * @version $Revision: 1.88.2.1 $ $Date: 2005/10/13 16:35:39 $
 * @package GalleryCore
 * @author Bharat Mediratta <bharat@menalto.com>
 */

/**
 * This class is a glue layer between the templating system and our various
 * callbacks that generate URLs, localized text, dates, themed widgets, etc.
 *
 * @package GalleryCore
 * @subpackage Classes
 */
class GalleryTemplateAdapter {

    /**
     * The number of times our block callbacks have been executed
     * @var array _callCount
     */
    var $_callCount;

    /**
     * The active theme
     *
     * @var object GalleryTheme
     * @access private
     */
    var $_theme;

    /**
     * Aggregation of text that we want to output at the bottom of the page,
     * useful for when we need to put javascript at the bottom.
     *
     * @var string $_trailer
     * @access private
     */
    var $_trailer;

    /**
     * Registered callbacks that will get executed during the trailer.
     *
     * @var array $_trailerCallbacks
     * @access private
     */
    var $_trailerCallbacks = array();

    /**
     * Current state of the progress bar.
     *
     * @var array $_progressBarStats
     * @access private
     */
    var $_progressBarStats;

    /**
     * Constructor
     */
    function GalleryTemplateAdapter() {
	$this->_callCount = array();
	$this->_theme = null;
	$this->_trailer = null;
	$this->_progressBarStats = null;
    }

    /**
     * Set the theme
     *
     * @param object GalleryTheme
     */
    function setTheme($theme) {
	$this->_theme = $theme;
    }

    /*************************************************************
     * Special purpose template callback methods.
     *************************************************************/

    /**
     * @see GalleryUrlGenerator::generateUrl()
     *
     * Return a valid Gallery URL, standalone or embedded.
     *
     * @param array data in key/value pairs
     * @return string a URL
     */
    function url($params, &$smarty) {
	global $gallery;

	if (isset($params['href'])) {
	    $hrefParams = array('href' => $params['href']);
	} else if (isset($params['params'])) {
	    /* Allow the user to pass in bulk params */
	    $hrefParams = $params['params'];
	} else {
	    $hrefParams = array();

	    /* Search for args and add them to the params */
	    $i = 1;
	    while (isset($params['arg' . $i])) {
		list ($key, $value) = explode('=', $params['arg' . $i]);
		$hrefParams[$key] = $value;
		$i++;
	    }
	}

	$forceSessionId = isset($params['forceSessionId']) ? $params['forceSessionId'] : null;
	if (isset($params['forceDirect'])) {
	    $hrefParams['forceDirect'] = $params['forceDirect'];
	}

	$urlGenerator =& $gallery->getUrlGenerator();
	$url = $urlGenerator->generateUrl($hrefParams, $forceSessionId);

	if (!empty($params['forJavascript'])) {
	    $url = str_replace('&amp;', '&', $url);
	}

	return $url;
    }

    /**
     * Return any hidden form variables that we want to embed in this form based on the
     * current session and request context.  We use this to pass the special "return" variable
     * forward, for example.
     *
     * @param array data in key/value pairs
     * @return a series of XHTML 1.0 compliant <input> elements
     */
    function hiddenFormVars($params, &$smarty) {
	global $gallery;
	$urlGenerator =& $gallery->getUrlGenerator();
	$vars = array();

	/* The 'return' url */
	if (GalleryUtilities::hasRequestVariable('return')) {
	    $vars['return'] = GalleryUtilities::getRequestVariables('return');
	}

	/* Remember the current url for getting back to where we came from */
	if (empty($vars['return'])) {
	    $currentView = $gallery->getCurrentView();
	    list ($ret, $view) = GalleryView::loadView($currentView);
	    if ($ret->isError()) {
		$viewDescription = '';
	    } else {
		list ($ret, $viewDescription) = $view->getViewDescription();
		if ($ret->isError()) {
		    $viewDescription = '';
		}
	    }
	    $vars['returnName'] = $viewDescription;
	    $vars['return'] = $urlGenerator->getNavigationReturnUrl();
	}

	/* Our navigation id */
	$navigationId = $urlGenerator->getNavigationId();
	if (!empty($navigationId)) {
	    $vars['navId'] = $navigationId;
	    unset($vars['return']);
	}

	/* Remember the original URL where this form was first shown */
	$vars['formUrl'] = GalleryUtilities::getRequestVariables('formUrl');
	if (empty($vars['formUrl'])) {
	    /* First time we load this form */
	    $vars['formUrl'] = $urlGenerator->getNavigationReturnUrl();
	}

	$out = '';
	foreach ($vars as $key => $value) {
	    $out .= sprintf('<input type="hidden" name="%s" value="%s"/>' . "\n",
			   GalleryUtilities::prefixFormVariable($key),
			   $value);
	}
	return $out;
    }

    /**
     * Return a valid Gallery date.
     *
     * @todo This needs to be refactored.
     *
     * @param array data in key/value pairs
     * @return string a URL
     */
    function date($params, &$smarty) {
	global $gallery;
	static $defaultFormat;
	$platform = $gallery->getPlatform();

	if (empty($params['format'])) {
	    if (!isset($defaultFormat)) {
		$defaultFormat = array('date' => '%x', 'time' => '%X', 'datetime' => '%c');
		list ($ret, $core) = GalleryCoreApi::fetchAllPluginParameters('module', 'core');
		if ($ret->isSuccess()) {
		    $defaultFormat = array('date' => $core['format.date'],
					   'time' => $core['format.time'],
					   'datetime' => $core['format.datetime']);
		}
	    }

	    $params['format'] =
		(!empty($params['style']) && isset($defaultFormat[$params['style']]))
		? $defaultFormat[$params['style']] : $defaultFormat['date'];
	}

	return $platform->strftime($params['format'],
	    !empty($params['timestamp']) ? $params['timestamp'] : null);
    }

    /**
     * @see GalleryTranslator::translate()
     */
    function text($params, &$smarty) {
	global $gallery;

	if (isset($params['l10Domain'])) {
	    $domain = $params['l10Domain'];
	} else {
	    $domain = $smarty->_tpl_vars['l10Domain'];
	}
	$translator =& $gallery->getTranslator();
	list ($ret, $text) = $translator->translateDomain($domain, $params);
	if ($ret->isError()) {
	    return $ret->getAsHtml();
	    return "[Translation error]";
	}

	if (!empty($params['forJavascript'])) {
	    $text = str_replace("'", "\\'", $text);
	}

	return $text;
    }

    /**
     * Return a transformed element name, useful when we're trying to use
     * Javascript to access a form element.
     *
     * @param array key => value attributes
     * @return HTML content
     */
    function formVar($params) {
	return GalleryUtilities::prefixFormVariable($params['var']);
    }

    /**
     * Delegate to the appropriate item class to render an image.
     *
     * @param array containing item, image, maxSize, fallback, and any img attributes
     * @param object Smarty the smarty instance
     * @return string HTML content
     */
    function image($params, &$smarty) {
	/* Ask the entity to render itself in HTML */
	list ($ret, $item) = GalleryCoreApi::loadEntitiesById($params['item']['id']);
	if ($ret->isError()) {
	    /* TODO: is there a more graceful way to handle this? */
	    return '[Render error: missing item]';
	}

	list ($ret, $entity) = GalleryCoreApi::loadEntitiesById($params['image']['id']);
	if ($ret->isError()) {
	    /* TODO: is there a more graceful way to handle this? */
	    return '[Render error: missing entity]';
	}

	unset($params['item']);
	unset($params['image']);
	if (isset($params['fallback'])) {
	    $fallback = $params['fallback'];
	} else {
	    $fallback = $params['fallback'] = null;
	}

	if ($entity->getId() == $item->getId()) {
	    $html = $item->render('HTML', $params);
	} else {
	    $html = $entity->render('HTML', $item, $params);
	}

	return !empty($html) ? $html : $fallback;
    }

    /**
     * Render head content
     *
     * @param array
     * @param object Smarty the smarty instance
     * @return string HTML content
     */
    function head($params, &$smarty) {
	global $gallery;
	$urlGenerator =& $gallery->getUrlGenerator();
	$templateVars =& $smarty->get_template_vars();
	$head = $templateVars['head'];
	$output = array("\n");

	/* Title */
	if (isset($head['title'])) {
	    $output[] = '<title>' . $head['title'] . "</title>\n";
	}

	/* Style */
	foreach ($head['style'] as $path) {
	    $output[] = sprintf('<link rel="stylesheet" type="text/css" href="%s"/>' . "\n",
				$urlGenerator->generateUrl(array('href' => $path)));
	}

	/* Javascript */
	if (isset($head['javascript'])) {
	    foreach ($head['javascript'] as $path) {
		$output[] = sprintf('<script type="text/javascript" src="%s"></script>' . "\n",
			$urlGenerator->generateUrl(array('href' => $path)));
	    }
	}

	/* Tpl to include. */
	foreach ($head['tpl'] as $path => $l10Domain) {
	    /* Guard template vars so that the include doesn't pollute our namespace */
	    $save = $smarty->_tpl_vars;
	    $smarty->_smarty_include(
		array('smarty_include_tpl_file' => "gallery:$path",
		      'smarty_include_vars' => array('l10Domain' => $l10Domain)));
	    $smarty->_tpl_vars = $save;
	}

	/* This should help out users whose browsers are confused about the character set */
	$output[] = '<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/>';

	return implode('', $output);
    }

    /**
     * Include our AutoCompletion template.
     *
     * @param array params
     * @param string content
     * @param object Smarty the smarty instance
     */
    function autoComplete($params, $content, &$smarty) {
	if (!isset($content)) {
	    if (!isset($this->_callCount['autoComplete'])) {
		$this->_callCount['autoComplete'] = 0;
	    }
	    return;
	}
	$url = trim($content);

	/* Guard template vars so that the include doesn't pollute our namespace */
	$save = $smarty->_tpl_vars;
	$smarty->_smarty_include(
	    array('smarty_include_tpl_file' => 'gallery:modules/core/templates/AutoComplete.tpl',
		  'smarty_include_vars' =>
			array('element' => $params['element'],
			      'url' => $url,
			      'callCount' => ++$this->_callCount['autoComplete'])));
	$smarty->_tpl_vars = $save;
    }

    /**
     * Include form inputs for dimensions.
     *
     * @param array params
     * @param object Smarty the smarty instance
     */
    function dimensions($params, &$smarty) {
	if (!isset($this->_callCount['dimensions'])) {
	    $this->_callCount['dimensions'] = 0;
	}

	/* Guard template vars so that the include doesn't pollute our namespace */
	$save = $smarty->_tpl_vars;
	$smarty->_smarty_include(
	    array('smarty_include_tpl_file' => 'gallery:modules/core/templates/Dimensions.tpl',
		  'smarty_include_vars' => array(
		      'formVar' => $params['formVar'],
		      'formVarId' => strtr($params['formVar'], '[]', '__'),
		      'width' => isset($params['width']) ? $params['width'] : null,
		      'height' => isset($params['height']) ? $params['height'] : null,
		      'callCount' => ++$this->_callCount['dimensions'])));
	$smarty->_tpl_vars = $save;
    }

    /**
     * Add hidden form elements to select a default submit button
     * that is used if enter is pressed in a text input.
     * Include this before any submit buttons are added to the form.
     *
     * @param array params
     * @param object Smarty the smarty instance
     */
    function defaultButton($params, &$smarty) {
	if (!isset($this->_callCount['defaultButton'])) {
	    $this->_callCount['defaultButton'] = 0;
	}

	/* Guard template vars so that the include doesn't pollute our namespace */
	$save = $smarty->_tpl_vars;
	$smarty->_smarty_include(
	    array('smarty_include_tpl_file' => 'gallery:modules/core/templates/DefaultButton.tpl',
		  'smarty_include_vars' => array(
		      'name' => $params['name'],
		      'callCount' => ++$this->_callCount['defaultButton'])));
	$smarty->_tpl_vars = $save;
    }

    /**
     * This takes an array and looks for view, subview, and controller to make
     * a linkid (being used as a css classname)
     *
     * @param array the items to make a css class out of
     * @return string the id of the css class
     */
    function linkId($params) {
	$linkId = 'gbLink';
	if (!empty($params['urlParams']['controller'])) {
	    $linkId .= '-' . $params['urlParams']['controller'];
	}
	if (!empty($params['view'])) {
	    $linkId .= '-' . $params['view'];
	} elseif (!empty($params['urlParams']['view'])) {
	    $linkId .= '-' . $params['urlParams']['view'];
	}
	if (!empty($params['urlParams']['subView'])) {
	    $linkId .= '-' . ($subView = $params['urlParams']['subView']);
	    if (preg_match('{^core\.Item(?:Edit|Move|Delete|CreateLink)(?:Single)?$}', $subView) &&
		    !empty($params['urlParams']['itemId'])) {
		/* Append item type for a few subViews, with fallback class without type */
		list ($ret, $item) =
		    GalleryCoreApi::loadEntitiesById($params['urlParams']['itemId']);
		if ($ret->isSuccess()) {
		    $type = $item->itemTypeName(false);
		    $fallbackLinkId = $linkId;
		    $linkId .= '-' . $type[1];
		}
	    }
	}
	return 'gbAdminLink ' . GalleryTemplateAdapter::_safeCssName($linkId) .
	    (isset($fallbackLinkId) ?
	     ' ' . GalleryTemplateAdapter::_safeCssName($fallbackLinkId) : '');
    }

    /**
     * This removes unsafe characters from a string so they can be used as a class
     * name or id in html and be addressed via css
     *
     * Purpose:  Removes characters from a string so that it can be used for an
     * html class name or id and be addressed via css
     *
     * @param string the input string
     * @return string
     * @access private
     */
    function _safeCssName($string) {
	$string = ereg_replace("[^-A-Za-z0-9_]", "_", $string);
	$string = ereg_replace('__+', '_', $string);
	$string = ereg_replace('[-_][-_]+', '-', $string);
	return $string;
    }

    function mainDivAttributes($params, &$smarty) {
	global $gallery;

	$classes = array();
	$userAgent = strtolower(GalleryUtilities::getServerVar('HTTP_USER_AGENT'));
	if (strpos($userAgent, 'safari') !== false) {
	    $classes[] = 'safari';
	} else if (strpos($userAgent, 'opera') !== false) {
	    $classes[] = 'opera';
	} else if (strpos($userAgent, 'msie') !== false) {
	    $classes[] = 'IE';
	} else if (strpos($userAgent, 'gecko/') !== false) {
	    $classes[] = 'gecko';
	}

	$translator =& $gallery->getTranslator();
	if ($translator->isRightToLeft()) {
	    $classes[] = 'rtl';
	}

	$classes = empty($classes) ? '' : ' class="' . implode(' ', $classes) . '"';
	return 'id="gallery"' . $classes;
    }

    function logoButton($params, &$smarty) {
	global $gallery;
	$urlGenerator =& $gallery->getUrlGenerator();
	list ($ret, $core) = GalleryCoreApi::loadPlugin('module', 'core', true);
	if ($ret->isError()) {
	    return $ret->wrap(__FILE__, __LINE__);
	}

	if ($params['type'] == 'gallery2' || $params['type'] == 'donate') {
	    list ($ret, $adminGroupId) =
		GalleryCoreApi::getPluginParameter('module', 'core', 'id.adminGroup');
	    if ($ret->isError()) {
		return;
	    }
	    list ($ret, $isAdmin) = GalleryCoreApi::isUserInGroup(
		$smarty->_tpl_vars['theme']['actingUserId'], $adminGroupId);
	    if ($ret->isError()) {
		return;
	    }
	    GalleryCoreApi::relativeRequireOnce('modules/core/module.inc');
	    $installedVersions = CoreModule::getInstalledVersions();
	}

	switch($params['type']) {
	case 'validation':
	    if ($gallery->getConfig('allowSessionAccess')) {
		/* Calculate a URI that we can use for the validation link */
		$validationUri = $urlGenerator->getCurrentUrl();
		$session =& $gallery->getSession();
		if ($session->isUsingCookies()) {
		    $validationUri = $urlGenerator->appendParamsToUrl(
			$validationUri, array($session->getKey() => $session->getId()));
		}
		$validationUri = sprintf(
		    'http://validator.w3.org/check?uri=%s&amp;ss=1',
		    urlencode(str_replace('&amp;', '&', $validationUri)));
	    } else {
		$validationUri = sprintf(
		    'javascript:alert(\'%s\');',
		    $core->translate(
			'Validation disabled until you set allowSessionAccess in config.php'));
	    }
	    return '<a href="' . $validationUri . '"><img ' .
		'src="' . $urlGenerator->generateUrl(array('href' => 'images/xhtml10.png')) . '" ' .
		'alt="' . $core->translate('This page is valid XHTML 1.0') . '" ' .
		'style="border-style: none" width="80" height="15"/></a>';

	case 'gallery2':
	    if (!$isAdmin) {
		/* Don't show exact patch release to non-admins */
		$installedVersions['gallery'] =
		    preg_replace('/^(.*?\..*?)(\.\d+)+/', '$1', $installedVersions['gallery']);
	    }
	    $version = $core->translate(
		array('text' => "Gallery %s", 'arg1' => $installedVersions['gallery']));
	    return '<a href="http://gallery.sourceforge.net">' .
		'<img src="' . $urlGenerator->generateUrl(array('href' => 'images/gallery.gif')) .
		'" ' .
		'alt="' . $version . '" '.
		'title="' . $version . '" ' .
		'style="border-style: none" width="80" height="15"/></a>';

	case 'donate':
	    if ($isAdmin) {
		return sprintf(
		    '<a href="%s"><img src="%s" alt="%s" title="%s" ' .
		    'style="border-style: none" width="80" height="15"/></a>',
		    $urlGenerator->generateUrl(
			array('href' => 'http://gallery.sourceforge.net/donate.php?donate_tag=' .
			      $installedVersions['gallery'])),
		    $urlGenerator->generateUrl(
			array('href' => 'modules/core/data/donate.png')),
		    $core->translate('Donate to the Gallery project'),
		    $core->translate('Donate to the Gallery project'));
	    }
	    break;

	case 'gallery2-version':
	    return sprintf(
		'<a href="%s"><img src="%s" alt="%s" title="%s" ' .
		'style="border-style: none" width="80" height="15"/></a>',
		$urlGenerator->generateUrl(
		    array('href' => 'modules/core/data/g2-unpossible.mp3')),
		$urlGenerator->generateUrl(
		    array('href' => 'modules/core/data/g2-unpossible.png')),
		$core->translate('G2.0: Unpossible!'),
		$core->translate('G2.0: Unpossible!'));
	}
    }

    function debug($params, &$smarty) {
	global $gallery;
	$debug = $gallery->getDebug();
	$profiling = $gallery->isProfiling('sql');

	$buf = '';
	if ($debug == 'buffered' || $profiling) {
	    $translator = $gallery->getTranslator();

	    /* don't worry about localizing this -- it's only debug output */
	    $buf .= '<div id="gpDebug"> <h3> Debug Output </h3>';
	    if ($debug == 'buffered') {
		$buf .= $gallery->getDebugBuffer();
	    }

	    if ($profiling) {
		$storage =& $gallery->getStorage();
		$buf .= '<span>' . $storage->getProfilingHtml() . '</span>';
	    }
	    $buf .= '</div>';
	}
	return $buf;
    }

    /**
     * Perform a theme related function.  Possible parameters are
     *   include => file to include inside the theme's templates/ dir
     *   url  => url to a file inside the themes dir
     *
     * @params array('include' => ..., 'url' => ...)
     * @param reference to Smarty
     */
    function theme($params, &$smarty) {
	global $gallery;

	if (isset($params['include'])) {
	    /* Guard template vars so that the include doesn't pollute our namespace */
	    $save = $smarty->_tpl_vars;
	    $smarty->_smarty_include(array(
		'smarty_include_tpl_file' =>
		    'gallery:themes/' . $this->_theme->getId(). '/templates/' . $params['include'],
		'smarty_include_vars' => $params));
	    $smarty->_tpl_vars = $save;
	} else if (isset($params['url'])) {
	    $urlGenerator =& $gallery->getUrlGenerator();
	    return $urlGenerator->generateUrl(
		array('href' => 'themes/' . $this->_theme->getId() . '/' . $params['url']));
	}
    }

    /**
     * Include a module's block into the current smarty page.  The only
     * required param is 'type' which should be of the form <module>.<blockname>
     * eg: "core.LoginBlock".  Any other parameters get passed on to the block itself.
     *
     * @params array('type' => <block descriptor>, ...)
     * @param reference to Smarty
     */
    function block($params, &$smarty) {
	list ($module, $file) = explode('.', $params['type']);
	$class = empty($params['class']) ? '' : ' ' . $params['class'];

	list ($ret, $pluginStatus) = GalleryCoreApi::fetchPluginStatus('module');
	if ($ret->isError()) {
	    /* What can we do here? */
	    return '[error fetching blocks]';
	}

	if (empty($pluginStatus[$module]['active'])) {
	    return;
	}

	if (isset($params['params'])) {
	    $params = $params['params'];
	}

	$params['class'] = "block-$module-$file$class";
	$params['l10Domain'] = "modules_$module";

	/* Guard template vars so that the include doesn't pollute our namespace */
	$save = $smarty->_tpl_vars;
	$smarty->_smarty_include(
	    array('smarty_include_tpl_file' => "gallery:modules/$module/templates/blocks/$file.tpl",
		  'smarty_include_vars' => $params));
	$smarty->_tpl_vars = $save;
    }

    /**
     * Include a module's container into the current smarty page.  The only
     * required param is 'type' which should be of the form <module>.<blockname>
     * eg: "core.LoginBlock".  Any other parameters get passed on to the block itself.
     *
     * This is like block() except it wraps actual content.
     *
     * @params array('type' => <block descriptor>, ...)
     * @param reference to Smarty
     */
    function container($params, $content, &$smarty) {
	if (!isset($content)) {
	    return;
	}

	list ($module, $file) = explode('.', $params['type']);
	/* Guard template vars so that the include doesn't pollute our namespace */
	$save = $smarty->_tpl_vars;
	$smarty->_smarty_include(
	    array('smarty_include_tpl_file' =>
		  "gallery:modules/$module/templates/containers/$file.tpl",
		  'smarty_include_vars' => array_merge(array('content' => $content),
						       $params)));
	$smarty->_tpl_vars = $save;
    }

    /**
     * Call back to a module to get it to preload some data for the template. The only required
     * param is 'type' which should be of the form <module>.<blockname> eg: "core.LoginBlock".
     * Any other parameters get passed on to the block itself.
     *
     * @params array('type' => <block descriptor>, ...)
     * @param reference to Smarty
     */
    function callback($params, &$smarty) {
	list ($module, $file) = explode('.', $params['type']);
	GalleryCoreApi::relativeRequireOnce("modules/$module/Callbacks.inc");

	$userId = $smarty->_tpl_vars['theme']['actingUserId'];
	$className = "${module}Callbacks";
	$class = new $className;
	$ret = $class->callback($params, $smarty, $file, $userId);
	if ($ret->isError()) {
	    /* What can we do with this error? */
	    global $gallery;
	    $gallery->debug("Error performing $params[type] callback");
	    $gallery->debug($ret->getAsHtml());
	}
    }

    /**
     * Add the content to our trailer block
     *
     * @param array
     * @param string content
     * @param object Smarty the smarty instance
     * @return string HTML content
     */
    function addToTrailer($params, $content, &$smarty) {
	if (!isset($content)) {
	    return;
	}
	$this->_trailer .= $content;
    }

    /**
     * Register a callback function to be executed when we run the trailer.
     *
     * @param array of arguments suitable to be used as an input for call_user_func()
     */
    function registerTrailerCallback($callback, $args) {
	$this->_trailerCallbacks[] = array('function' => $callback, 'args' => $args);
    }

    function trailer($params, &$smarty) {
	print $this->_trailer;

	foreach ($this->_trailerCallbacks as $callback) {
	    $ret = call_user_func_array($callback['function'], $callback['args']);
	    if (is_array($ret)) {
		$ret = $ret[0];
	    }
	}
    }

    function updateProgressBar($title, $description, $percentComplete) {
	static $coreModule;
	if (!isset($coreModule)) {
	    list ($ret, $coreModule) = GalleryCoreApi::loadPlugin('module', 'core');
	    if ($ret->isError()) {
		return $ret->wrap(__FILE__, __LINE__);
	    }
	}

	if (empty($this->_progressBarStats)) {
	    $this->_progressBarStats['startTime'] = time();
	}

	/*
	 * Calculate the time remaining
	 *
	 * TODO: Use a weighted measurement to provide a balanced estimate.  Consider the case
	 * where the first 50% goes really quickly and the second 50% goes really slowly; the
	 * estimate will be wildly inaccurate at the transition.
	 */
	if ($percentComplete > 0 &&
		$percentComplete < 1 && time() > $this->_progressBarStats['startTime']) {
	    $elapsed = (int)(time() - $this->_progressBarStats['startTime']);
	    $timeRemaining = ($elapsed / $percentComplete) - $elapsed;
	    $timeRemaining = $coreModule->translate(
		array('text' => 'Estimated time remaining: %d:%02d',
		      'arg1' => (int)($timeRemaining / 60),
		      'arg2' => $timeRemaining % 60));
	} else {
	    $timeRemaining = '';
	}

	/* it is possible to not have this function compiled into php */
	$memoryUsed = (function_exists('memory_get_usage')) ? memory_get_usage() : 0;

	/* A disabled memory_limit is -1, 0 crashes php */
	$memoryTotal = (0 < ini_get('memory_limit')) ? ini_get('memory_limit') : 0;

	/*
	 * Ensure that percentComplete is in a dotted-decimal format.  Since
	 * the immediateView is dealing in percentages, anything beyond two decimal
	 * places is unnecessary.
	 */
	$percentComplete = GalleryUtilities::roundToString($percentComplete, 2);

	$memoryInfo = $coreModule->translate(
	    array('text' => 'Memory used: %s, total: %s',
		  'arg1' => $memoryUsed,
		  'arg2' => $memoryTotal));
	printf('<script type="text/javascript">' .
	       'updateProgressBar("%s", "%s", "%s", "%s", "%s");</script>',
	       $title, $description, $percentComplete, $timeRemaining, $memoryInfo);
	flush();
	return GalleryStatus::success();
    }

    function resetProgressBarStats() {
	$this->_progressBarStats = array();
    }

    function errorProgressBar($status) {
	printf('<script type="text/javascript">errorProgressBar("%s");</script>',
	       $status->getAsHtml());
    }

    function completeProgressBar($continueUrl) {
	$continueUrl = str_replace('&amp;', '&', $continueUrl);
	printf('<script type="text/javascript">completeProgressBar("%s");</script>', $continueUrl);
    }
}
?>