<?php
// Copyright (C) 2010-2015 Combodo SARL
//
//   This file is part of iTop.
//
//   iTop is free software; you can redistribute it and/or modify	
//   it under the terms of the GNU Affero General Public License as published by
//   the Free Software Foundation, either version 3 of the License, or
//   (at your option) any later version.
//
//   iTop 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 Affero General Public License for more details.
//
//   You should have received a copy of the GNU Affero General Public License
//   along with iTop. If not, see <http://www.gnu.org/licenses/>


/**
 * Class WebPage
 *
 * @copyright   Copyright (C) 2010-2015 Combodo SARL
 * @license     http://opensource.org/licenses/AGPL-3.0
 */


/**
 * Generic interface common to CLI and Web pages
 */
Interface Page
{
	public function output();
	public function add($sText);
	public function p($sText);
	public function pre($sText);
	public function add_comment($sText);
	public function table($aConfig, $aData, $aParams = array());
}
 


/**
 * Simple helper class to ease the production of HTML pages
 *
 * This class provide methods to add content, scripts, includes... to a web page 
 * and renders the full web page by putting the elements in the proper place & order
 * when the output() method is called.
 * Usage:
 * 	$oPage = new WebPage("Title of my page");
 *	$oPage->p("Hello World !");
 *	$oPage->output();
 */
class WebPage implements Page
{
    protected $s_title;
    protected $s_content;
    protected $s_deferred_content;
    protected $a_scripts;
    protected $a_dict_entries;
    protected $a_styles;
    protected $a_include_scripts;
    protected $a_include_stylesheets;
    protected $a_headers;
    protected $a_base;
    protected $iNextId;
    protected $iTransactionId;
	protected $sContentType;
	protected $sContentDisposition;
	protected $sContentFileName;
	protected $bTrashUnexpectedOutput;
	protected $s_sOutputFormat;
	protected $a_OutputOptions;
	protected $bPrintable;
	    
    public function __construct($s_title, $bPrintable = false)
    {
        $this->s_title = $s_title;
        $this->s_content = "";
        $this->s_deferred_content = '';
        $this->a_scripts = array();
        $this->a_dict_entries = array();
        $this->a_styles = array();
        $this->a_linked_scripts = array();
        $this->a_linked_stylesheets = array();
        $this->a_headers = array();
        $this->a_base = array( 'href' => '', 'target' => '');
        $this->iNextId = 0;
        $this->iTransactionId = 0;
        $this->sContentType = '';
        $this->sContentDisposition = '';
        $this->sContentFileName = '';
		$this->bTrashUnexpectedOutput = false;
		$this->s_OutputFormat = utils::ReadParam('output_format', 'html');
		$this->a_OutputOptions = array();
		$this->bPrintable = $bPrintable;
        ob_start(); // Start capturing the output
    }
	
	/**
	 * Change the title of the page after its creation
	 */
    public function set_title($s_title)
    {
        $this->s_title = $s_title;
    }
    
	/**
	 * Specify a default URL and a default target for all links on a page
	 */
    public function set_base($s_href = '', $s_target = '')
    {
        $this->a_base['href'] = $s_href;
        $this->a_base['target'] = $s_target;
    }
    
	/**
	 * Add any text or HTML fragment to the body of the page
	 */
    public function add($s_html)
    {
        $this->s_content .= $s_html;
    }
    
	/**
	 * Add any text or HTML fragment (identified by an ID) at the end of the body of the page
	 * This is useful to add hidden content, DIVs or FORMs that should not
	 * be embedded into each other.	 	 
	 */
    public function add_at_the_end($s_html, $sId = '')
    {
        $this->s_deferred_content .= $s_html;
    }
    
	/**
	 * Add a paragraph to the body of the page
	 */
    public function p($s_html)
    {
        $this->add($this->GetP($s_html));
    }
    
	/**
	 * Add a pre-formatted text to the body of the page
	 */
    public function pre($s_html)
    {
        $this->add('<pre>'.$s_html.'</pre>');
    }
    
	/**
	 * Add a comment
	 */
    public function add_comment($sText)
    {
        $this->add('<!--'.$sText.'-->');
    }
	/**
	 * Add a paragraph to the body of the page
	 */
    public function GetP($s_html)
    {
        return "<p>$s_html</p>\n";
    }
    
	/**
	* Adds a tabular content to the web page
	* @param Hash $aConfig Configuration of the table: hash array of 'column_id' => 'Column Label'
	* @param Hash $aData Hash array. Data to display in the table: each row is made of 'column_id' => Data. A column 'pkey' is expected for each row
	* @param Hash $aParams Hash array. Extra parameters for the table.
	* @return void
	*/	  
	public function table($aConfig, $aData, $aParams = array())
	{
		$this->add($this->GetTable($aConfig, $aData, $aParams));
	}
	
	public function GetTable($aConfig, $aData, $aParams = array())
	{
		$oAppContext = new ApplicationContext();
		
		static $iNbTables = 0;
		$iNbTables++;
		$sHtml = "";
		$sHtml .= "<table class=\"listResults\">\n";
		$sHtml .= "<thead>\n";
		$sHtml .= "<tr>\n";
		foreach($aConfig as $sName=>$aDef)
		{
			$sHtml .= "<th title=\"".$aDef['description']."\">".$aDef['label']."</th>\n";
		}
		$sHtml .= "</tr>\n";
		$sHtml .= "</thead>\n";
		$sHtml .= "<tbody>\n";
		foreach($aData as $aRow)
		{
			$sHtml .= $this->GetTableRow($aRow, $aConfig);
		}
		$sHtml .= "</tbody>\n";
		$sHtml .= "</table>\n";
		return $sHtml;
	}
	
	public function GetTableRow($aRow, $aConfig)
	{
		$sHtml = '';
		if (isset($aRow['@class'])) // Row specific class, for hilighting certain rows
		{
			$sHtml .= "<tr class=\"{$aRow['@class']}\">";				
		}
		else
		{
			$sHtml .= "<tr>";
		}
		foreach($aConfig as $sName=>$aAttribs)
		{
			$sClass = isset($aAttribs['class']) ? 'class="'.$aAttribs['class'].'"' : '';
			$sValue = ($aRow[$sName] === '') ? '&nbsp;' : $aRow[$sName];
			$sHtml .= "<td $sClass>$sValue</td>";
		}
		$sHtml .= "</tr>";
		return $sHtml;	
	}
    
	/**
	 * Add some Javascript to the header of the page
	 */
    public function add_script($s_script)
    {
        $this->a_scripts[] = $s_script;
    }
    
	/**
	 * Add some Javascript to the header of the page
	 */
    public function add_ready_script($s_script)
    {
        // Do nothing silently... this is not supported by this type of page...
    }

	/**
	 * Add a dictionary entry for the Javascript side
	 */
    public function add_dict_entry($s_entryId)
    {
        $this->a_dict_entries[$s_entryId] = Dict::S($s_entryId);
    }
    

	/**
	 * Add some CSS definitions to the header of the page
	 */
    public function add_style($s_style)
    {
        $this->a_styles[] = $s_style;
    }

	/**
	 * Add a script (as an include, i.e. link) to the header of the page
	 */
    public function add_linked_script($s_linked_script)
    {
        $this->a_linked_scripts[$s_linked_script] = $s_linked_script;
    }

	/**
	 * Add a CSS stylesheet (as an include, i.e. link) to the header of the page
	 */
    public function add_linked_stylesheet($s_linked_stylesheet, $s_condition = "")
    {
        $this->a_linked_stylesheets[] = array( 'link' => $s_linked_stylesheet, 'condition' => $s_condition);
    }

	public function add_saas($sSaasRelPath)
	{
		$sCssRelPath = utils::GetCSSFromSASS($sSaasRelPath);
		$sRootUrl =  utils::GetAbsoluteUrlAppRoot();
		if ($sRootUrl === '')
		{
			// We're running the setup of the first install...
			$sRootUrl = '../';
		}
		$sCSSUrl = $sRootUrl.$sCssRelPath;
		$this->add_linked_stylesheet($sCSSUrl);
	}
	/**
	 * Add some custom header to the page
	 */
    public function add_header($s_header)
    {
        $this->a_headers[] = $s_header;
    }

	/**
	 * Add needed headers to the page so that it will no be cached
	 */
    public function no_cache()
    {
        $this->add_header("Cache-Control: no-cache, must-revalidate");  // HTTP/1.1
        $this->add_header("Expires: Fri, 17 Jul 1970 05:00:00 GMT");    // Date in the past
    }

	/**
	 * Build a special kind of TABLE useful for displaying the details of an object from a hash array of data
	 */
	public function details($aFields)
	{

		$this->add($this->GetDetails($aFields));
    }
    
    /**
     * Whether or not the page is a PDF page
     * @return boolean
     */
    public function is_pdf()
    {
    	return false;
    }

	/**
	 * Records the current state of the 'html' part of the page output
	 * @return mixed The current state of the 'html' output
	 */    
    public function start_capture()
    {
    	return strlen($this->s_content);
    }
    
    /**
     * Returns the part of the html output that occurred since the call to start_capture
     * and removes this part from the current html output
     * @param $offset mixed The value returned by start_capture
     * @return string The part of the html output that was added since the call to start_capture
     */
    public function end_capture($offset)
    {
    	$sCaptured = substr($this->s_content, $offset);
    	$this->s_content = substr($this->s_content, 0, $offset);
    	return $sCaptured;
    }
	
	/**
	 * Build a special kind of TABLE useful for displaying the details of an object from a hash array of data
	 */
	public function GetDetails($aFields)
	{
		$sHtml = "<table class=\"details\">\n";
		$sHtml .= "<tbody>\n";
		foreach($aFields as $aAttrib)
		{
			$sHtml .= "<tr>\n";
			// By Rom, for csv import, proposed to show several values for column selection
			if (is_array($aAttrib['value']))
			{
				$sHtml .= "<td class=\"label\">".$aAttrib['label']."</td><td>".implode("</td><td>", $aAttrib['value'])."</td>\n";
			}
			else
			{
				$sHtml .= "<td class=\"label\">".$aAttrib['label']."</td><td>".$aAttrib['value']."</td>\n";
			}
			$sComment = (isset($aAttrib['comments'])) ? $aAttrib['comments'] : '&nbsp;';
			$sInfo = (isset($aAttrib['infos'])) ? $aAttrib['infos'] : '&nbsp;';
			$sHtml .= "<td>$sComment</td><td>$sInfo</td>\n";
    		$sHtml .= "</tr>\n";
		}
		$sHtml .= "</tbody>\n";
		$sHtml .= "</table>\n";
		return $sHtml;
    }

	/**
	 * Build a set of radio buttons suitable for editing a field/attribute of an object (including its validation)
	 * @param $aAllowedValues hash Array of value => display_value
	 * @param $value mixed Current value for the field/attribute
	 * @param $iId mixed Unique Id for the input control in the page
	 * @param $sFieldName string The name of the field, attr_<$sFieldName> will hold the value for the field
	 * @param $bMandatory bool Whether or not the field is mandatory
	 * @param $bVertical bool Disposition of the radio buttons vertical or horizontal
	 * @param $sValidationField string HTML fragment holding the validation field (exclamation icon...)
	 * @return string The HTML fragment corresponding to the radio buttons
	 */
	public function GetRadioButtons($aAllowedValues, $value, $iId, $sFieldName, $bMandatory, $bVertical, $sValidationField)
	{
		$idx = 0;
		$sHTMLValue = '';
		foreach($aAllowedValues as $key => $display_value)
		{
			if ((count($aAllowedValues) == 1) && ($bMandatory == 'true') )
			{
				// When there is only once choice, select it by default
				$sSelected = ' checked';
			}
			else
			{
				$sSelected = ($value == $key) ? ' checked' : '';
			}
			$sHTMLValue .= "<input type=\"radio\" id=\"{$iId}_{$key}\" name=\"radio_$sFieldName\" onChange=\"$('#{$iId}').val(this.value).trigger('change');\" value=\"$key\"$sSelected><label class=\"radio\" for=\"{$iId}_{$key}\">&nbsp;$display_value</label>&nbsp;";
			if ($bVertical)
			{
				if ($idx == 0)
				{
					// Validation icon at the end of the first line
					$sHTMLValue .= "&nbsp;{$sValidationField}\n";							
				}
				$sHTMLValue .= "<br>\n";
			}
			$idx++;
		}
		$sHTMLValue .= "<input type=\"hidden\" id=\"$iId\" name=\"$sFieldName\" value=\"$value\"/>";
		if (!$bVertical)					
		{
			// Validation icon at the end of the line
			$sHTMLValue .= "&nbsp;{$sValidationField}\n";
		}
		return $sHTMLValue;
	}
	
	/**
	 * Discard unexpected output data (such as PHP warnings)
	 * This is a MUST when the Page output is DATA (download of a document, download CSV export, download ...)
	 */	
	public function TrashUnexpectedOutput()
	{
		$this->bTrashUnexpectedOutput = true;
	}

	/**
	 * Read the output buffer and deal with its contents:
	 * - trash unexpected output if the flag has been set
	 * - report unexpected behaviors such as the output buffering being stopped
	 * 
	 * Possible improvement: I've noticed that several output buffers are stacked,
	 * if they are not empty, the output will be corrupted. The solution would
	 * consist in unstacking all of them (and concatenate the contents).	 	 
	 */
	protected function ob_get_clean_safe()
	{
		$sOutput = ob_get_contents();
		if ($sOutput === false)
		{
			$sMsg = "Design/integration issue: No output buffer. Some piece of code has called ob_get_clean() or ob_end_clean() without calling ob_start()";
			if ($this->bTrashUnexpectedOutput)
			{
				IssueLog::Error($sMsg);
				$sOutput = '';
			}
			else
			{
				$sOutput = $sMsg;
			}
		}
		else
		{
			ob_end_clean(); // on some versions of PHP doing so when the output buffering is stopped can cause a notice
			if ($this->bTrashUnexpectedOutput)
			{
				if (trim($sOutput) != '')
				{
					if (Utils::GetConfig() && Utils::GetConfig()->Get('debug_report_spurious_chars'))
					{
						IssueLog::Error("Trashing unexpected output:'$sOutput'\n");
					}
				}
				$sOutput = '';
			}
		}
		return $sOutput;
	}

	/**
	 * Outputs (via some echo) the complete HTML page by assembling all its elements
	 */
    public function output()
    {
        foreach($this->a_headers as $s_header)
        {
            header($s_header);
        }

        $s_captured_output = $this->ob_get_clean_safe();
        echo "<!DOCTYPE html PUBLIC \"-//W3C//DTD XHTML 1.0 Strict//EN\" \"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd\">\n";
        echo "<html>\n";
        echo "<head>\n";
		echo "<meta http-equiv=\"Content-Type\" content=\"text/html; charset=utf-8\" />\n";
		echo "<meta name=\"viewport\" content=\"width=device-width, initial-scale=1.0, shrink-to-fit=no\" />";
        echo "<title>".htmlentities($this->s_title, ENT_QUOTES, 'UTF-8')."</title>\n";
        echo $this->get_base_tag();
        foreach($this->a_linked_scripts as $s_script)
        {
        	// Make sure that the URL to the script contains the application's version number
        	// so that the new script do NOT get reloaded from the cache when the application is upgraded
        	if (strpos($s_script, '?') === false)
        	{
        		$s_script .= "?itopversion=".ITOP_VERSION;
        	}
        	else
        	{
        		$s_script .= "&itopversion=".ITOP_VERSION;
        	}
            echo "<script type=\"text/javascript\" src=\"$s_script\"></script>\n";
        }
        if (count($this->a_scripts)>0)
        {
            echo "<script type=\"text/javascript\">\n";
            foreach($this->a_scripts as $s_script)
            {
                echo "$s_script\n";
            }
            echo "</script>\n";
        }
        $this->output_dict_entries();
        foreach($this->a_linked_stylesheets as $a_stylesheet)
        {
			if (strpos($a_stylesheet['link'], '?') === false)
			{
				$s_stylesheet = $a_stylesheet['link']."?itopversion=".ITOP_VERSION;
			}
			else
			{
				$s_stylesheet = $a_stylesheet['link']."&itopversion=".ITOP_VERSION;
			}
			if ($a_stylesheet['condition'] != "")
			{
				echo "<!--[if {$a_stylesheet['condition']}]>\n";
			}
			echo "<link rel=\"stylesheet\" type=\"text/css\" href=\"{$s_stylesheet}\" />\n";
			if ($a_stylesheet['condition'] != "")
			{
				echo "<![endif]-->\n";
			}
        }
        
        if (count($this->a_styles)>0)
        {
            echo "<style>\n";
            foreach($this->a_styles as $s_style)
            {
                echo "$s_style\n";
            }
            echo "</style>\n";
        }
        if (class_exists('MetaModel') && MetaModel::GetConfig())
        {
 			echo "<link rel=\"shortcut icon\" href=\"".utils::GetAbsoluteUrlAppRoot()."images/favicon.ico?itopversion=".ITOP_VERSION."\" />\n";
        }
        echo "</head>\n";
        echo "<body>\n";
        echo self::FilterXSS($this->s_content);
        if (trim($s_captured_output) != "")
        {
            echo "<div class=\"raw_output\">".self::FilterXSS($s_captured_output)."</div>\n";
        }
        echo '<div id="at_the_end">'.self::FilterXSS($this->s_deferred_content).'</div>';
        echo "</body>\n";
        echo "</html>\n";

        if (class_exists('DBSearch'))
        {
            DBSearch::RecordQueryTrace();
        }
        if (class_exists('ExecutionKPI'))
        {
            ExecutionKPI::ReportStats();
        }
    }

	/**
	 * Build a series of hidden field[s] from an array
	 */
	public function add_input_hidden($sLabel, $aData)
	{
		foreach($aData as $sKey => $sValue)
		{
			// Note: protection added to protect against the Notice 'array to string conversion' that appeared with PHP 5.4
			// (this function seems unused though!)
			if (is_scalar($sValue))
			{
				$this->add("<input type=\"hidden\" name=\"".$sLabel."[$sKey]\" value=\"$sValue\">");
			}
		}
	}

	protected function get_base_tag()
	{
		$sTag = '';
        if (($this->a_base['href'] != '') || ($this->a_base['target'] != ''))
        {
        	$sTag = '<base ';
        	if (($this->a_base['href'] != ''))
        	{
        		$sTag .= "href =\"{$this->a_base['href']}\" ";
			}
        	if (($this->a_base['target'] != ''))
        	{
        		$sTag .= "target =\"{$this->a_base['target']}\" ";
			}
			$sTag .= " />\n";
		}
		return $sTag;
	}
	
	/**
	 * Get an ID (for any kind of HTML tag) that is guaranteed unique in this page
	 * @return int The unique ID (in this page)
	 */
	public function GetUniqueId()
	{
		return $this->iNextId++;
	}

	/**
	 * Set the content-type (mime type) for the page's content
	 * @param $sContentType string
	 * @return void
	 */
	public function SetContentType($sContentType)
	{
		$this->sContentType = $sContentType;
	}
		
	/**
	 * Set the content-disposition (mime type) for the page's content
	 * @param $sDisposition string The disposition: 'inline' or 'attachment'
	 * @param $sFileName string The original name of the file
	 * @return void
	 */
	public function SetContentDisposition($sDisposition, $sFileName)
	{
		$this->sContentDisposition = $sDisposition;
		$this->sContentFileName = $sFileName;
	}
		
	/**
	 * Set the transactionId of the current form
	 * @param $iTransactionId integer
	 * @return void
	 */
	public function SetTransactionId($iTransactionId)
	{
		$this->iTransactionId = $iTransactionId;
	}
	
	/**
	 * Returns the transactionId of the current form
	 * @return integer The current transactionID
	 */
	public function GetTransactionId()
	{
		return $this->iTransactionId;
	}
	
	public static function FilterXSS($sHTML)
	{
		return str_ireplace('<script', '&lt;script', $sHTML);
	}
	
	/**
	 * What is the currently selected output format
	 * @return string The selected output format: html, pdf...
	 */
	public function GetOutputFormat()
	{
		return $this->s_OutputFormat;
	}

	/**
	 * Check whether the desired output format is possible or not
	 * @param string $sOutputFormat The desired output format: html, pdf...
	 * @return bool True if the format is Ok, false otherwise
	 */
	function IsOutputFormatAvailable($sOutputFormat)
	{
		$bResult = false;
		switch($sOutputFormat)
		{
			case 'html':
			$bResult = true; // Always supported
			break;
			
			case 'pdf':
			$bResult = @is_readable(APPROOT.'lib/MPDF/mpdf.php');
			break;
		}
		return $bResult;
	}

	/**
	 * Check whether the output must be printable (using print.css, for sure!)
	 * @return bool ...
	 */
	public function IsPrintableVersion()
	{
		return $this->bPrintable;
	}

	/** 
	 * Retrieves the value of a named output option for the given format
	 * @param string $sFormat The format: html or pdf
	 * @param string $sOptionName The name of the option
	 * @return mixed false if the option was never set or the options's value
	 */
	public function GetOutputOption($sFormat, $sOptionName)
	{
		if (isset($this->a_OutputOptions[$sFormat][$sOptionName]))
		{
			return $this->a_OutputOptions[$sFormat][$sOptionName];
		}
		return false;
	}
	/**
	 * Sets a named output option for the given format
	 * @param string $sFormat The format for which to set the option: html or pdf
	 * @param string $sOptionName the name of the option
	 * @param mixed $sValue The value of the option
	 */
	public function SetOutputOption($sFormat, $sOptionName, $sValue)
	{
		if (!isset($this->a_OutputOptions[$sFormat]))
		{
			$this->a_OutputOptions[$sFormat] = array($sOptionName => $sValue);
		}
		else
		{
			$this->a_OutputOptions[$sFormat][$sOptionName] = $sValue;
		}
	}
	
	public function RenderPopupMenuItems($aActions, $aFavoriteActions = array())
	{
		$sPrevUrl = '';
		$sHtml = '';
		if (!$this->IsPrintableVersion())
		{
			foreach ($aActions as $aAction)
			{
				$sClass = isset($aAction['css_classes']) ? ' class="'.implode(' ', $aAction['css_classes']).'"' : '';
				$sOnClick = isset($aAction['onclick']) ? ' onclick="'.htmlspecialchars($aAction['onclick'], ENT_QUOTES, "UTF-8").'"' : '';
				$sTarget = isset($aAction['target']) ? " target=\"{$aAction['target']}\"" : "";
				if (empty($aAction['url']))
				{
					if ($sPrevUrl != '') // Don't output consecutively two separators...
					{
						$sHtml .= "<li>{$aAction['label']}</li>";			
					}
					$sPrevUrl = '';
				}
				else
				{
					$sHtml .= "<li><a $sTarget href=\"{$aAction['url']}\"$sClass $sOnClick>{$aAction['label']}</a></li>";
					$sPrevUrl = $aAction['url'];
				}
			}
			$sHtml .= "</ul></li></ul></div>";
			foreach(array_reverse($aFavoriteActions) as $aAction)
			{
				$sTarget = isset($aAction['target']) ? " target=\"{$aAction['target']}\"" : "";
				$sHtml .= "<div class=\"actions_button\"><a $sTarget href='{$aAction['url']}'>{$aAction['label']}</a></div>";			
			}
		}		
		return $sHtml;
	}

	protected function output_dict_entries($bReturnOutput = false)
	{
		$sHtml = '';
		if (count($this->a_dict_entries)>0)
		{
			$sHtml .= "<script type=\"text/javascript\">\n";
			$sHtml .= "var Dict = {};\n";
			$sHtml .= "Dict._entries = {};\n";
			$sHtml .= "Dict.S = function(sEntry) {\n";
			$sHtml .= "   if (sEntry in Dict._entries)\n";
			$sHtml .= "   {\n";
			$sHtml .= "      return Dict._entries[sEntry];\n";
			$sHtml .= "   }\n";
			$sHtml .= "   else\n";
			$sHtml .= "   {\n";
			$sHtml .= "      return sEntry;\n";
			$sHtml .= "   }\n";
			$sHtml .= "};\n";
			foreach($this->a_dict_entries as $s_entry => $s_value)
			{
				$sHtml .= "Dict._entries['$s_entry'] = '".addslashes($s_value)."';\n";
			}
			$sHtml .= "</script>\n";
		}
		
		if ($bReturnOutput)
		{
			return $sHtml;
		}
		else
		{
			echo $sHtml;
		}
	}
}


interface iTabbedPage
{
	public function AddTabContainer($sTabContainer, $sPrefix = '');

	public function AddToTab($sTabContainer, $sTabLabel, $sHtml);

	public function SetCurrentTabContainer($sTabContainer = '');

	public function SetCurrentTab($sTabLabel = '');
	
	/**
	 * Add a tab which content will be loaded asynchronously via the supplied URL
	 * 
	 * Limitations:
	 * Cross site scripting is not not allowed for security reasons. Use a normal tab with an IFRAME if you want to pull content from another server.
	 * Static content cannot be added inside such tabs.
	 * 
	 * @param string $sTabLabel The (localised) label of the tab
	 * @param string $sUrl The URL to load (on the same server)
	 * @param boolean $bCache Whether or not to cache the content of the tab once it has been loaded. flase will cause the tab to be reloaded upon each activation.
	 * @since 2.0.3
	 */
	public function AddAjaxTab($sTabLabel, $sUrl, $bCache = true);
	
	public function GetCurrentTab();

	public function RemoveTab($sTabLabel, $sTabContainer = null);

	/**
	 * Finds the tab whose title matches a given pattern
	 * @return mixed The name of the tab as a string or false if not found
	 */
	public function FindTab($sPattern, $sTabContainer = null);
}

/**
 * Helper class to implement JQueryUI tabs inside a page
 */
class TabManager
{
	protected $m_aTabs;
	protected $m_sCurrentTabContainer;
	protected $m_sCurrentTab;
	
	public function __construct()
	{
		$this->m_aTabs = array();
		$this->m_sCurrentTabContainer = '';
		$this->m_sCurrentTab = '';
	}
	
	public function AddTabContainer($sTabContainer, $sPrefix = '')
	{
		$this->m_aTabs[$sTabContainer] = array('prefix' => $sPrefix, 'tabs' => array());
		return "\$Tabs:$sTabContainer\$";
	}

	public function AddToCurrentTab($sHtml)
	{
		$this->AddToTab($this->m_sCurrentTabContainer, $this->m_sCurrentTab, $sHtml);
	}
	
	public function GetCurrentTabLength($sHtml)
	{
		$iLength = isset($this->m_aTabs[$this->m_sCurrentTabContainer]['tabs'][$this->m_sCurrentTab]['html']) ? strlen($this->m_aTabs[$this->m_sCurrentTabContainer]['tabs'][$this->m_sCurrentTab]['html']): 0;
		return $iLength;
	}
	
	/**
	 * Truncates the given tab to the specifed length and returns the truncated part
	 * @param string $sTabContainer The tab container in which to truncate the tab
	 * @param string $sTab The name/identifier of the tab to truncate
	 * @param integer $iLength The length/offset at which to truncate the tab
	 * @return string The truncated part
	 */
	public function TruncateTab($sTabContainer, $sTab, $iLength)
	{
		$sResult = substr($this->m_aTabs[$this->m_sCurrentTabContainer]['tabs'][$this->m_sCurrentTab]['html'], $iLength);
		$this->m_aTabs[$this->m_sCurrentTabContainer]['tabs'][$this->m_sCurrentTab]['html'] = substr($this->m_aTabs[$this->m_sCurrentTabContainer]['tabs'][$this->m_sCurrentTab]['html'], 0, $iLength);
		return $sResult;	
	}
	
	public function TabExists($sTabContainer, $sTab)
	{
		return isset($this->m_aTabs[$sTabContainer]['tabs'][$sTab]);
	}
	
	public function TabsContainerCount()
	{
		return count($this->m_aTabs);
	}
	
	public function AddToTab($sTabContainer, $sTabLabel, $sHtml)
	{
		if (!isset($this->m_aTabs[$sTabContainer]['tabs'][$sTabLabel]))
		{
			// Set the content of the tab
			$this->m_aTabs[$sTabContainer]['tabs'][$sTabLabel] = array(
				'type' => 'html',
				'html' => $sHtml,
			);
		}
		else
		{
			if ($this->m_aTabs[$sTabContainer]['tabs'][$sTabLabel]['type'] != 'html')
			{
				throw new Exception("Cannot add HTML content to the tab '$sTabLabel' of type '{$this->m_aTabs[$sTabContainer]['tabs'][$sTabLabel]['type']}'");
			}
			// Append to the content of the tab
			$this->m_aTabs[$sTabContainer]['tabs'][$sTabLabel]['html'] .= $sHtml;
		}
		return ''; // Nothing to add to the page for now
	}

	public function SetCurrentTabContainer($sTabContainer = '')
	{
		$sPreviousTabContainer = $this->m_sCurrentTabContainer;
		$this->m_sCurrentTabContainer = $sTabContainer;
		return $sPreviousTabContainer;
	}

	public function SetCurrentTab($sTabLabel = '')
	{
		$sPreviousTab = $this->m_sCurrentTab;
		$this->m_sCurrentTab = $sTabLabel;
		return $sPreviousTab;
	}
	
	/**
	 * Add a tab which content will be loaded asynchronously via the supplied URL
	 * 
	 * Limitations:
	 * Cross site scripting is not not allowed for security reasons. Use a normal tab with an IFRAME if you want to pull content from another server.
	 * Static content cannot be added inside such tabs.
	 * 
	 * @param string $sTabLabel The (localised) label of the tab
	 * @param string $sUrl The URL to load (on the same server)
	 * @param boolean $bCache Whether or not to cache the content of the tab once it has been loaded. flase will cause the tab to be reloaded upon each activation.
	 * @since 2.0.3
	 */
	public function AddAjaxTab($sTabLabel, $sUrl, $bCache = true)
	{
		// Set the content of the tab
		$this->m_aTabs[$this->m_sCurrentTabContainer]['tabs'][$sTabLabel] = array(
			'type' => 'ajax',
			'url' => $sUrl,
			'cache' => $bCache,
		);
		return ''; // Nothing to add to the page for now
	}
	
	
	public function GetCurrentTabContainer()
	{
		return $this->m_sCurrentTabContainer;
	}
	
	public function GetCurrentTab()
	{
		return $this->m_sCurrentTab;
	}

	public function RemoveTab($sTabLabel, $sTabContainer = null)
	{
		if ($sTabContainer == null)
		{
			$sTabContainer = $this->m_sCurrentTabContainer;
		}
		if (isset($this->m_aTabs[$sTabContainer]['tabs'][$sTabLabel]))
		{
			// Delete the content of the tab
			unset($this->m_aTabs[$sTabContainer]['tabs'][$sTabLabel]);
				
			// If we just removed the active tab, let's reset the active tab
			if (($this->m_sCurrentTabContainer == $sTabContainer) &&  ($this->m_sCurrentTab == $sTabLabel))
			{
				$this->m_sCurrentTab = '';
			}
		}
	}

	/**
	 * Finds the tab whose title matches a given pattern
	 * @return mixed The actual name of the tab (as a string) or false if not found
	 */
	public function FindTab($sPattern, $sTabContainer = null)
	{
		$result = false;
		if ($sTabContainer == null)
		{
			$sTabContainer = $this->m_sCurrentTabContainer;
		}
		foreach($this->m_aTabs[$sTabContainer]['tabs'] as $sTabLabel => $void)
		{
			if (preg_match($sPattern, $sTabLabel))
			{
				$result = $sTabLabel;
				break;
			}
		}
		return $result;
	}

	/**
	 * Make the given tab the active one, as if it were clicked
	 * DOES NOT WORK: apparently in the *old* version of jquery
	 * that we are using this is not supported... TO DO upgrade
	 * the whole jquery bundle...
	 */
	public function SelectTab($sTabContainer, $sTabLabel)
	{
		$container_index = 0;
		$tab_index = 0;
		foreach($this->m_aTabs as $sCurrentTabContainerName => $aTabs)
		{
			if ($sTabContainer == $sCurrentTabContainerName)
			{
				foreach($aTabs['tabs'] as $sCurrentTabLabel => $void)
				{
					if ($sCurrentTabLabel == $sTabLabel)
					{
						break;
					}
					$tab_index++;
				}
				break;
			}
			$container_index++;
		}
		$sSelector = '#tabbedContent_'.$container_index.' > ul';
		return "window.setTimeout(\"$('$sSelector').tabs('select', $tab_index);\", 100);"; // Let the time to the tabs widget to initialize
	}
	
	public function RenderIntoContent($sContent, WebPage $oPage)
	{
		// Render the tabs in the page (if any)
		foreach($this->m_aTabs as $sTabContainerName => $aTabs)
		{
			$sTabs = '';
			$sPrefix = $aTabs['prefix'];
			$container_index = 0;
			if (count($aTabs['tabs']) > 0)
			{
				if ($oPage->IsPrintableVersion())
				{
					$oPage->add_ready_script(
<<< EOF
oHiddeableChapters = {};
EOF
					);
					$sTabs = "<!-- tabs -->\n<div id=\"tabbedContent_{$sPrefix}{$container_index}\" class=\"light\">\n";
					$i = 0;
					foreach($aTabs['tabs'] as $sTabName => $aTabData)
					{
						$sTabNameEsc = addslashes($sTabName);
						$sTabId = "tab_{$sPrefix}{$container_index}$i";
						switch($aTabData['type'])
						{
							case 'ajax':
							$sTabHtml = '';
							$sUrl = $aTabData['url'];	
							$oPage->add_ready_script(
<<< EOF
$.post('$sUrl', {printable: '1'}, function(data){
	$('#$sTabId > .printable-tab-content').append(data);
});
EOF
							);
							break;
							
							case 'html':
							default:
							$sTabHtml = $aTabData['html'];
						}
						$sTabs .= "<div class=\"printable-tab\" id=\"$sTabId\"><h2 class=\"printable-tab-title\">".htmlentities($sTabName, ENT_QUOTES, 'UTF-8')."</h2><div class=\"printable-tab-content\">".$sTabHtml."</div></div>\n";	
						$oPage->add_ready_script(
<<< EOF
oHiddeableChapters['$sTabId'] = '$sTabNameEsc';
EOF
						);
						$i++;
					}
					$sTabs .= "</div>\n<!-- end of tabs-->\n";
				}
				else
				{
					$sTabs = "<!-- tabs -->\n<div id=\"tabbedContent_{$sPrefix}{$container_index}\" class=\"light\">\n";
					$sTabs .= "<ul>\n";
					// Display the unordered list that will be rendered as the tabs
					$i = 0;
					foreach($aTabs['tabs'] as $sTabName => $aTabData)
					{
						switch($aTabData['type'])
						{
							case 'ajax':
							$sTabs .= "<li data-cache=\"".($aTabData['cache'] ? 'true' : 'false')."\"><a href=\"{$aTabData['url']}\" class=\"tab\"><span>".htmlentities($sTabName, ENT_QUOTES, 'UTF-8')."</span></a></li>\n";
							break;
							
							case 'html':
							default:
							$sTabs .= "<li><a href=\"#tab_{$sPrefix}{$container_index}$i\" class=\"tab\"><span>".htmlentities($sTabName, ENT_QUOTES, 'UTF-8')."</span></a></li>\n";	
						}
						$i++;
					}
					$sTabs .= "</ul>\n";
					// Now add the content of the tabs themselves
					$i = 0;
					foreach($aTabs['tabs'] as $sTabName => $aTabData)
					{
						switch($aTabData['type'])
						{
							case 'ajax':
							// Nothing to add
							break;
							
							case 'html':
							default:
							$sTabs .= "<div id=\"tab_{$sPrefix}{$container_index}$i\">".$aTabData['html']."</div>\n";	
						}
						$i++;
					}
					$sTabs .= "</div>\n<!-- end of tabs-->\n";
				}
			}
			$sContent = str_replace("\$Tabs:$sTabContainerName\$", $sTabs, $sContent);
			$container_index++;
		}
		return $sContent;
	}
}