<?php
/**
 * EGroupware - Document merge print
 *
 * @link http://www.egroupware.org
 * @author Ralf Becker <RalfBecker-AT-outdoor-training.de>
 * @package api
 * @subpackage storage
 * @copyright (c) 2007-16 by Ralf Becker <RalfBecker-AT-outdoor-training.de>
 * @license http://opensource.org/licenses/gpl-license.php GPL - GNU General Public License
 * @version $Id$
 */

namespace EGroupware\Api\Storage;

use DOMDocument;
use EGroupware\Api;
use EGroupware\Api\Mail;
use EGroupware\Api\Vfs;
use EGroupware\Collabora\Conversion;
use EGroupware\Stylite;
use tidy;
use uiaccountsel;
use XSLTProcessor;
use ZipArchive;

// explicit import old, non-namespaced phpgwapi classes

/**
 * Document merge print
 *
 * @todo move apply_styles call into merge_string to run for each entry merged and not all together to lower memory requirements
 */
abstract class Merge
{
	/**
	 * Preference, path where we look for merge templates
	 */
	public const PREF_TEMPLATE_DIR = 'document_dir';

	/**
	 * Preference, path to special documents that are listed first
	 */
	public const PREF_DEFAULT_TEMPLATE = 'default_document';

	/**
	 * Preference, path where we will put the generated document
	 */
	const PREF_STORE_LOCATION = "merge_store_path";

	/**
	 * Preference, placeholders for creating the filename of the generated document
	 */
	const PREF_DOCUMENT_FILENAME = "document_download_name";

	/**
	 * List of placeholders
	 */
	const DOCUMENT_FILENAME_OPTIONS = [
		'$$document$$'      => 'Template name',
		'$$link_title$$'    => 'Entry link-title',
		'$$contact_title$$' => 'Contact link-title',
		'$$current_date$$'  => 'Current date',
	];

	/**
	 * Instance of the addressbook_bo class
	 *
	 * @var addressbook_bo
	 */
	var $contacts;

	/**
	 * Datetime format according to user preferences
	 *
	 * @var string
	 */
	var $datetime_format = 'Y-m-d H:i';

	/**
	 * Fields that are to be treated as datetimes, when merged into spreadsheets
	 * Do not include placeholders in field list
	 */
	var $date_fields = [];

	/**
	 * Fields that are numeric, for special numeric handling
	 * Do not include placeholders in field list
	 */
	protected $numeric_fields = [];

	/**
	 * Mimetype of document processed by merge
	 *
	 * @var string
	 */
	var $mimetype;

	/**
	 * Plugins registered by extending class to create a table with multiple rows
	 *
	 * $$table/$plugin$$ ... $$endtable$$
	 *
	 * Callback returns replacements for row $n (stringing with 0) or null if no further rows
	 *
	 * @var array $plugin => array callback($plugin,$id,$n)
	 */
	var $table_plugins = array();

	/**
	 * Export limit in number of entries or some non-numerical value, if no export allowed at all, empty means no limit
	 *
	 * Set by constructor to $GLOBALS[egw_info][server][export_limit]
	 *
	 * @var int|string
	 */
	public $export_limit;

	public $public_functions = array(
		"merge_entries" => true
	);

	/**
	 * Configuration for HTML Tidy to clean up any HTML content that is kept
	 */
	public static $tidy_config = array(
		'output-xml'        => true,    // Entity encoding
		'show-body-only'    => true,
		'output-encoding'   => 'utf8',
		'input-encoding'    => 'utf8',
		'quote-ampersand'   => false,    // Prevent double encoding
		'quote-nbsp'        => true,    // XSLT can handle spaces easier
		'preserve-entities' => true,
		'wrap'              => 0,        // Wrapping can break output
	);

	/**
	 * Parse HTML styles into target document style, if possible
	 *
	 * Apps not using html in there own data should set this with Customfields::use_html($app)
	 * to avoid memory and time consuming html processing.
	 */
	protected $parse_html_styles = true;

	/**
	 * Enable this to report memory_usage to error_log
	 *
	 * @var boolean
	 */
	public $report_memory_usage = false;

	/**
	 * Save sent emails.  Used when merge template is an email.  Default is true,
	 * to save sent emails in your sent folder.
	 *
	 * @var boolean
	 */
	public $keep_emails = true;

	/**
	 * The merge document is an XML document
	 *
	 * If the document is an XML document, special handling is needed in some cases
	 */
	protected $is_xml = false;

	/**
	 * Line feed character(s) for the document.
	 * This may be different based on the document type.
	 *
	 * @var string
	 */
	protected $line_feed = "\n";

	/**
	 * Constructor
	 */
	function __construct()
	{
		// Common messages are in preferences
		Api\Translation::add_app('preferences');
		// All contact fields are in addressbook
		Api\Translation::add_app('addressbook');

		$this->contacts = new Api\Contacts();

		$this->datetime_format = $GLOBALS['egw_info']['user']['preferences']['common']['dateformat'] . ' ' .
			($GLOBALS['egw_info']['user']['preferences']['common']['timeformat'] == 12 ? 'h:i a' : 'H:i');

		$this->export_limit = self::getExportLimit();
	}

	/**
	 * Hook returning options for export_limit_excepted groups
	 *
	 * @param array $config
	 */
	public static function hook_export_limit_excepted($config)
	{
		$accountsel = new uiaccountsel();

		return '<input type="hidden" value="" name="newsettings[export_limit_excepted]" />' .
			$accountsel->selection('newsettings[export_limit_excepted]', 'export_limit_excepted', $config['export_limit_excepted'], 'both', 4);
	}

	/**
	 * Get all replacements, must be implemented in extending class
	 *
	 * Can use eg. the following high level methods:
	 * - contact_replacements($contact_id,$prefix='')
	 * - format_datetime($time,$format=null)
	 *
	 * @param int $id id of entry
	 * @param string &$content =null content to create some replacements only if they are use
	 * @return array|boolean array with replacements or false if entry not found
	 */
	abstract protected function get_replacements($id, &$content = null);

	/**
	 * Return if merge-print is implemented for given mime-type (and/or extension)
	 *
	 * @param string $mimetype eg. text/plain
	 * @param string $extension only checked for applications/msword and .rtf
	 */
	static public function is_implemented($mimetype, $extension = null)
	{
		static $zip_available = null;
		if(is_null($zip_available))
		{
			$zip_available = check_load_extension('zip') &&
				class_exists('ZipArchive');    // some PHP has zip extension, but no ZipArchive (eg. RHEL5!)
		}
		switch($mimetype)
		{
			case 'application/msword':
				if(strtolower($extension) != '.rtf')
				{
					break;
				}
			case 'application/rtf':
			case 'text/rtf':
				return true;    // rtf files
			case 'application/vnd.oasis.opendocument.text':    // oo text
			case 'application/vnd.oasis.opendocument.spreadsheet':    // oo spreadsheet
			case 'application/vnd.oasis.opendocument.presentation':
			case 'application/vnd.oasis.opendocument.text-template':
			case 'application/vnd.oasis.opendocument.spreadsheet-template':
			case 'application/vnd.oasis.opendocument.presentation-template':
				if(!$zip_available)
				{
					break;
				}
				return true;    // open office write xml files
			case 'application/vnd.openxmlformats-officedocument.wordprocessingml.document':    // ms word 2007 xml format
			case 'application/vnd.openxmlformats-officedocument.wordprocessingml.d':    // mimetypes in vfs are limited to 64 chars
			case 'application/vnd.ms-word.document.macroenabled.12':
			case 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet':    // ms excel 2007 xml format
			case 'application/vnd.openxmlformats-officedocument.spreadsheetml.shee':
			case 'application/vnd.ms-excel.sheet.macroenabled.12':
				if(!$zip_available)
				{
					break;
				}
				return true;    // ms word xml format
			case 'application/xml':
				return true;    // alias for text/xml, eg. ms office 2003 word format
			case 'message/rfc822':
				return true; // ToDo: check if you are theoretical able to send mail
			case 'application/x-yaml':
				return true;    // yaml file, plain text with marginal syntax support for multiline replacements
			default:
				if(substr($mimetype, 0, 5) == 'text/')
				{
					return true;    // text files
				}
				break;
		}
		return false;

		// As browsers not always return correct mime types, one could use a negative list instead
		//return !($mimetype == Api\Vfs::DIR_MIME_TYPE || substr($mimetype,0,6) == 'image/');
	}

	/**
	 * Return replacements for a contact
	 *
	 * @param int|string|array $contact contact-array or id
	 * @param string $prefix ='' prefix like eg. 'user'
	 * @param boolean $ignore_acl =false true: no acl check
	 * @return array
	 */
	public function contact_replacements($contact, $prefix = '', $ignore_acl = false, &$content = '')
	{
		if(!is_array($contact))
		{
			$contact = $this->contacts->read($contact, $ignore_acl);
		}
		if(!is_array($contact))
		{
			return array();
		}

		$replacements = array();
		foreach(array_keys($this->contacts->contact_fields) as $name)
		{
			$value = $contact[$name] ?? '';
			if(!$value)
			{
				continue;
			}
			switch($name)
			{
				case 'created':
				case 'modified':
					if($value)
					{
						$value = Api\DateTime::to($value);
					}
					break;
				case 'bday':
					if($value)
					{
						try
						{
							$value = Api\DateTime::to($value, true);
						}
						catch (\Exception $e)
						{
							unset($e);    // ignore exception caused by wrongly formatted date
						}
					}
					break;
				case 'owner':
				case 'creator':
				case 'modifier':
					$value = Api\Accounts::username($value);
					break;
				case 'cat_id':
					if($value)
					{
						// if cat-tree is displayed, we return a full category path not just the name of the cat
						$use = $GLOBALS['egw_info']['server']['cat_tab'] == 'Tree' ? 'path' : 'name';
						$cats = array();
						foreach(is_array($value) ? $value : explode(',', $value) as $cat_id)
						{
							$cats[] = $GLOBALS['egw']->categories->id2name($cat_id, $use);
						}
						$value = implode(', ', $cats);
					}
					break;
				case 'jpegphoto':    // returning a link might make more sense then the binary photo
					if($contact['photo'])
					{
						$value = Api\Framework::getUrl(Api\Framework::link('/index.php', $contact['photo']));
					}
					break;
				case 'tel_prefer':
					if($value && $contact[$value])
					{
						$value = $contact[$value];
					}
					break;
				case 'account_id':
					if($value)
					{
						$replacements['$$' . ($prefix ? $prefix . '/' : '') . 'account_lid$$'] = $GLOBALS['egw']->accounts->id2name($value);
					}
					break;
			}
			if($name != 'photo')
			{
				$replacements['$$' . ($prefix ? $prefix . '/' : '') . $name . '$$'] = $value;
			}
		}

		// Formatted address, according to preference or country
		foreach(['one', 'two'] as $adr)
		{
			switch($this->contacts->addr_format_by_country($contact["adr_{$adr}_countryname"]))
			{
				case 'city_state_postcode':
					$formatted_placeholder = $contact["adr_{$adr}_locality"] . " " .
						$contact["adr_{$adr}_region"] . "  " . $contact["adr_{$adr}_postalcode"];
					break;
				case 'postcode_city':
				default:
					$formatted_placeholder = $contact["adr_{$adr}_postalcode"] . ' ' . $contact["adr_{$adr}_locality"];
					break;
			}
			$replacements['$$adr_' . $adr . '_formatted$$'] = $formatted_placeholder;
		}

		// need to load all cfs for $ignore_acl=true
		$replacements = array_merge($replacements,  // array_merge as they might already be set with their raw value
			$this->customfield_replacements($contact, $prefix, $content,
				$ignore_acl ? Customfields::get('addressbook', true) : $this->contacts->customfields));

		if($content && strpos($content, '$$#') !== FALSE)
		{
			$this->cf_link_to_expand($contact, $content, $replacements, 'addressbook');
		}

		// Add in extra cat field
		$cats = array();
		foreach(is_array($contact['cat_id']) ? $contact['cat_id'] : (empty($contact['cat_id']) ? [] : explode(',', $contact['cat_id'])) as $cat_id)
		{
			if(!$cat_id)
			{
				continue;
			}
			if($GLOBALS['egw']->categories->id2name($cat_id, 'main') != $cat_id)
			{
				$path = explode(' / ', $GLOBALS['egw']->categories->id2name($cat_id, 'path'));
				unset($path[0]); // Drop main
				$cats[$GLOBALS['egw']->categories->id2name($cat_id, 'main')][] = implode(' / ', $path);
			}
			elseif($cat_id)
			{
				$cats[$cat_id] = array();
			}
		}
		$replacements['$$' . ($prefix ? $prefix . '/' : '') . 'categories$$'] = '';
		foreach($cats as $main => $cat)
		{
			$replacements['$$' . ($prefix ? $prefix . '/' : '') . 'categories$$'] .= $GLOBALS['egw']->categories->id2name($main, 'name')
				. (count($cat) > 0 ? ': ' : '') . implode(', ', $cats[$main]) . "\n";
		}
		return $replacements;
	}

	/**
	 * General method to return custom-fields replacements
	 *
	 * Date(-time) and numeric field are registered in $this->cf_link_to_expand, no need to do here.
	 *
	 * @param array $data video or course array
	 * @param string $prefix =''
	 * @param ?string& $content
	 * @param array|string|null $cfs array, app-name or null
	 * @return array
	 */
	protected function customfield_replacements(array $data, string $prefix='', &$content = null, $cfs=null)
	{
		if (is_string($cfs)) $cfs = Customfields::get($cfs);
		if (!$cfs || !is_array($cfs)) return [];

		$replacements = [];
		foreach($cfs as $name => $field)
		{
			$name = '#' . $name;
			if(!isset($data[$name]) || (string)$data[$name] === '')
			{
				$replacements['$$' . ($prefix ? $prefix . '/' : '') . $name . '$$'] = '';
				continue;
			}
			$replacements['$$' . ($prefix ? $prefix . '/' : '') . $name . '$$'] =
				// use raw data for yaml, no user-preference specific formatting
				$this->mimetype == 'application/x-yaml' || $field['type'] == 'htmlarea' ? (string)$data[$name] :
					Customfields::format($field, (string)$data[$name]);
		}
		return $replacements;
	}

	/**
	 * Get links for the given record
	 *
	 * Uses egw_link system to get link titles
	 *
	 * @param string app Name of current app
	 * @param string id ID of current entry
	 * @param string only_app Restrict links to only given application
	 * @param string[] exclude Exclude links to these applications
	 * @param string style  One of:
	 *    'title' - plain text, just the title of the link
	 *    'link' - URL to the entry
	 *    'href' - HREF tag wrapped around the title
	 */
	protected function get_links($app, $id, $only_app = '', $exclude = array(), $style = 'title')
	{
		$links = Api\Link::get_links($app, $id, $only_app);
		$link_titles = array();
		foreach($links as $link_info)
		{
			// Using only_app only returns the ID
			if(!is_array($link_info) && $only_app && $only_app[0] !== '!')
			{
				$link_info = array(
					'app' => $only_app,
					'id'  => $link_info
				);
			}
			if($exclude && in_array($link_info['id'], $exclude))
			{
				continue;
			}

			$title = Api\Link::title($link_info['app'], $link_info['id']);

			if($style == 'href' || $style == 'link')
			{
				$link = Api\Link::view($link_info['app'], $link_info['id'], $link_info);
				if($link_info['app'] != Api\Link::VFS_APPNAME)
				{
					// Set app to false so we always get an external link
					$link = str_replace(',', '%2C', $GLOBALS['egw']->framework->link('/index.php', $link, false));
				}
				else
				{
					$link = Api\Framework::link($link, array());
				}
				// Prepend site
				if($link[0] == '/')
				{
					$link = Api\Framework::getUrl($link);
				}

				$title = $style == 'href' ? Api\Html::a_href(Api\Html::htmlspecialchars($title), $link) : $link;
			}
			$link_titles[] = $title;
		}
		return implode("\n", $link_titles);
	}

	/**
	 * Get all link placeholders
	 *
	 * Calls get_links() repeatedly to get all the combinations for the content.
	 *
	 * @param $app String appname
	 * @param $id String ID of record
	 * @param $prefix
	 * @param $content String document content
	 */
	protected function get_all_links($app, $id, $prefix, &$content)
	{
		$array = array();
		$pattern = '@\$\$(links_attachments|links|attachments|link)\/?(?<style>title|href|link)?(?:\/?(?<app>[a-z_]*))?(?:\/(?<field>[^$]+))?\$\$@';
		static $link_cache = null;
		$matches = null;
		if(preg_match_all($pattern, $content, $matches))
		{
			foreach($matches[0] as $i => $placeholder)
			{
				$placeholder = substr($placeholder, 2, -2);
				if($link_cache[$id][$placeholder])
				{
					$array[$placeholder] = $link_cache[$id][$placeholder];
					continue;
				}
				switch($matches[1][$i])
				{
					case 'link':
						// Link to current record
						$title = Api\Link::title($app, $id);
						if(class_exists('EGroupware\Stylite\Vfs\Links\StreamWrapper') && $app != Api\Link::VFS_APPNAME)
						{
							$title = Stylite\Vfs\Links\StreamWrapper::entry2name($app, $id, $title);
						}

						$link = Api\Link::view($app, $id);
						if($app != Api\Link::VFS_APPNAME)
						{
							// Set app to false so we always get an external link
							$link = str_replace(',', '%2C', $GLOBALS['egw']->framework->link('/index.php', $link, false));
						}
						else
						{
							$link = Api\Framework::link($link, array());
						}
						// Prepend site
						if($link[0] == '/')
						{
							$link = Api\Framework::getUrl($link);
						}

						// Formatting
						if($matches[2][$i] == 'title')
						{
							$link = $title;
						}
						else
						{
							if($matches[2][$i] == 'href')
							{
								// Turn on HTML style parsing or the link will be escaped
								$this->parse_html_styles = true;
								$link = Api\Html::a_href(Api\Html::htmlspecialchars($title), $link);
							}
						}

						$array['$$' . ($prefix ? $prefix . '/' : '') . $placeholder . '$$'] = $link;
						break;
					case 'links':
						$link_app = $matches['app'][$i] ? $matches['app'][$i] : '!' . Api\Link::VFS_APPNAME;
						if($matches['app'][$i] && $matches['field'][$i])
						{
							// Want a field from a linked entry - find the first one from that app
							$links = Api\Link::get_links($app, $id, $link_app);
							$link = array_shift($links);
							$linked_replacements = $this->get_app_replacements($link_app, $link, '$$' . $matches['field'][$i] . '$$');
							$array['$$' . ($prefix ? $prefix . '/' : '') . $placeholder . '$$'] = $linked_replacements[$this->prefix('', $matches['field'][$i], '$$')];
						}
						else
						{
							// Titles from all linked entries
							$array['$$' . ($prefix ? $prefix . '/' : '') . $placeholder . '$$'] = $this->get_links($app, $id, $link_app, array(), $matches[2][$i]);
						}
						break;
					case 'attachments':
						$array['$$' . ($prefix ? $prefix . '/' : '') . $placeholder . '$$'] = $this->get_links($app, $id, Api\Link::VFS_APPNAME, array(), $matches[2][$i]);
						break;
					default:
						$array['$$' . ($prefix ? $prefix . '/' : '') . $placeholder . '$$'] = $this->get_links($app, $id, $matches[3][$i], array(), $matches[2][$i]);
						break;
				}
				$link_cache[$id][$placeholder] = $array[$placeholder];
			}
		}
		return $array;
	}

	/**
	 * Get share placeholder
	 *
	 * If the placeholder is present in the content, the share will be automatically
	 * created.  Valid placeholders:
	 * $$share$$ - A link to the entry
	 * $$share-files$$ - A link to filemanager showing files of the entry
	 * $$share/writable$$ - An editable link to the entry, using current user's permission
	 * $$share-files/writable$$ - Link to filemanager with write access
	 */
	protected function share_placeholder($app, $id, $prefix, &$content)
	{
		$replacements = array();

		// Skip if no content or content has no share placeholder (fast check)
		if(!$content || strpos($content, '$$' . $this->prefix($prefix, 'share')) === FALSE)
		{
			return $replacements;
		}

		$matches = null;
		preg_match_all('/\${2}' . $this->prefix($prefix, 'share') . '[^\$]*\${2}/', $content, $matches);
		list($placeholders) = $matches;

		if(!$GLOBALS['egw_info']['user']['apps']['stylite'])
		{
			foreach($placeholders as $p)
			{
				$replacements[$p] = lang('EPL Only');
			}
			return $replacements;
		}
		foreach($placeholders as $index => $placeholder)
		{
			// Get or create the share
			try
			{
				$share = $this->create_share($app, $id, $placeholder);

				$replacements[$placeholder] = $share ? Api\Sharing::share2link($share) : '';
			}
			catch (Exception $e)
			{
				_egw_log_exception($e, $headline);
				$replacements[$placeholder] = lang('Error');
				continue;
			}
		}

		return $replacements;
	}

	/**
	 * Create a share for an entry
	 *
	 * @param string $app
	 * @param string $id
	 * @param String $content
	 * @return \EGroupware\Api\Sharing
	 */
	protected function create_share($app, $id, &$content)
	{
		// Check if some other process created the share (with custom options)
		// and put it in the session cache for us
		$path = "$app::$id";
		$session = \EGroupware\Api\Cache::getSession(Api\Sharing::class, $path);
		if($session && $session['share_path'] == $path)
		{
			Api\Cache::unsetSession(Api\Sharing::class, $path);
			return $session;
		}

		$matches = null;
		preg_match_all('/\${2}([^\/\$]+\/)?share(-files(_only)?)?(\/writable)?\${2}/', $content, $matches);
		list($placeholders, , $files, , $writable) = $matches;

		// Need to create the share here.
		// No way to know here if it should be writable, or who it's going to
		$mode = $writable[0] == "/writable" ? Api\Sharing::WRITABLE : Api\Sharing::READONLY;
		$path = $files[0] !== '-files_only' ? $path : "/apps/$app/$id";
		$recipients = array();
		$extra = array();

		if($files[0] == '-files')
		{
			$extra['include_files'] = true;
		}
		$extra['share_writable'] |= ($mode == Api\Sharing::WRITABLE ? 1 : 0);

		return \EGroupware\Stylite\Link\Sharing::create('', $path, $mode, NULL, $recipients, $extra);
	}

	/**
	 * Format a datetime
	 *
	 * @param int|string|DateTime $time unix timestamp or Y-m-d H:i:s string (in user time!)
	 * @param string $format =null format string, default $this->datetime_format
	 * @return string
	 * @deprecated use Api\DateTime::to($time='now',$format='')
	 */
	protected function format_datetime($time, $format = null)
	{
		trigger_error(__METHOD__ . ' is deprecated, use Api\DateTime::to($time, $format)', E_USER_DEPRECATED);
		if(is_null($format))
		{
			$format = $this->datetime_format;
		}

		return Api\DateTime::to($time, $format);
	}

	/**
	 * Checks if current user is excepted from the export-limit:
	 * a) access to admin application
	 * b) he or one of his memberships is named in export_limit_excepted config var
	 *
	 * @return boolean
	 */
	public static function is_export_limit_excepted()
	{
		static $is_excepted = null;

		if(is_null($is_excepted))
		{
			$is_excepted = isset($GLOBALS['egw_info']['user']['apps']['admin']);

			// check export-limit and fail if user tries to export more entries then allowed
			if(!$is_excepted && (is_array($export_limit_excepted = $GLOBALS['egw_info']['server']['export_limit_excepted']) ||
					is_array($export_limit_excepted = unserialize($export_limit_excepted))))
			{
				$id_and_memberships = $GLOBALS['egw']->accounts->memberships($GLOBALS['egw_info']['user']['account_id'], true);
				$id_and_memberships[] = $GLOBALS['egw_info']['user']['account_id'];
				$is_excepted = (bool)array_intersect($id_and_memberships, $export_limit_excepted);
			}
		}
		return $is_excepted;
	}

	/**
	 * Checks if there is an exportlimit set, and returns
	 *
	 * @param string $app ='common' checks and validates app_limit, if not set returns the global limit
	 * @return mixed - no if no export is allowed, false if there is no restriction and int as there is a valid restriction
	 *        you may have to cast the returned value to int, if you want to use it as number
	 */
	public static function getExportLimit($app = 'common')
	{
		static $exportLimitStore = array();
		if(empty($app))
		{
			$app = 'common';
		}
		//error_log(__METHOD__.__LINE__.' called with app:'.$app);
		if(!array_key_exists($app, $exportLimitStore))
		{
			//error_log(__METHOD__.__LINE__.' -> '.$app_limit.' '.function_backtrace());
			$exportLimitStore[$app] = $GLOBALS['egw_info']['server']['export_limit'] ?? null;
			if($app != 'common')
			{
				$app_limit = Api\Hooks::single('export_limit', $app);
				if($app_limit)
				{
					$exportLimitStore[$app] = $app_limit;
				}
			}
			//error_log(__METHOD__.__LINE__.' building cache for app:'.$app.' -> '.$exportLimitStore[$app]);
			if(empty($exportLimitStore[$app]))
			{
				$exportLimitStore[$app] = false;
				return false;
			}

			if(is_numeric($exportLimitStore[$app]))
			{
				$exportLimitStore[$app] = (int)$exportLimitStore[$app];
			}
			else
			{
				$exportLimitStore[$app] = 'no';
			}
			//error_log(__METHOD__.__LINE__.' -> '.$exportLimit);
		}
		//error_log(__METHOD__.__LINE__.' app:'.$app.' -> '.$exportLimitStore[$app]);
		return $exportLimitStore[$app];
	}

	/**
	 * hasExportLimit
	 * checks wether there is an exportlimit set, and returns true or false
	 * @param mixed $app_limit app_limit, if not set checks the global limit
	 * @param string $checkas [AND|ISALLOWED], AND default; if set to ISALLOWED it is checked if Export is allowed
	 *
	 * @return bool - true if no export is allowed or a limit is set, false if there is no restriction
	 */
	public static function hasExportLimit($app_limit, $checkas = 'AND')
	{
		if(strtoupper($checkas) == 'ISALLOWED')
		{
			return (empty($app_limit) || ($app_limit != 'no' && $app_limit > 0));
		}
		if(empty($app_limit))
		{
			return false;
		}
		if($app_limit == 'no')
		{
			return true;
		}
		if($app_limit > 0)
		{
			return true;
		}
	}

	/**
	 * Merges a given document with contact data
	 *
	 * @param string $document path/url of document
	 * @param array $ids array with contact id(s)
	 * @param string &$err error-message on error
	 * @param string $mimetype mimetype of complete document, eg. text/*, application/vnd.oasis.opendocument.text, application/rtf
	 * @param array $fix =null regular expression => replacement pairs eg. to fix garbled placeholders
	 * @return string|boolean merged document or false on error
	 */
	public function &merge($document, $ids, &$err, $mimetype, array $fix = null)
	{
		if(!($content = file_get_contents($document)))
		{
			$err = lang("Document '%1' does not exist or is not readable for you!", $document);
			$ret = false;
			return $ret;
		}

		if(self::hasExportLimit($this->export_limit) && !self::is_export_limit_excepted() && count($ids) > (int)$this->export_limit)
		{
			$err = lang('No rights to export more than %1 entries!', (int)$this->export_limit);
			$ret = false;
			return $ret;
		}

		$this->apply_mimetype($mimetype, $document);

		try
		{
			$content = $this->merge_string($content, $ids, $err, $mimetype, $fix);
		}
		catch (\Exception $e)
		{
			_egw_log_exception($e);
			$err = $e->getMessage();
			$ret = false;
			return $ret;
		}
		return $content;
	}

	protected function apply_styles(&$content, $mimetype, $mso_application_progid = null)
	{
		if(!isset($mso_application_progid))
		{
			$matches = null;
			$mso_application_progid = $mimetype == 'application/xml' &&
			preg_match('/' . preg_quote('<?mso-application progid="', '/') . '([^"]+)' . preg_quote('"?>', '/') . '/', substr($content, 0, 200), $matches) ?
				$matches[1] : '';
		}
		// Tags we can replace with the target document's version
		$replace_tags = array();
		switch($mimetype . $mso_application_progid)
		{
			case 'application/vnd.oasis.opendocument.text':    // oo text
			case 'application/vnd.oasis.opendocument.spreadsheet':    // oo spreadsheet
			case 'application/vnd.oasis.opendocument.presentation':
			case 'application/vnd.oasis.opendocument.text-template':
			case 'application/vnd.oasis.opendocument.spreadsheet-template':
			case 'application/vnd.oasis.opendocument.presentation-template':
				$doc = new DOMDocument();
				$xslt = new XSLTProcessor();
				$doc->load(EGW_INCLUDE_ROOT . '/api/templates/default/Merge/openoffice.xslt');
				$xslt->importStyleSheet($doc);

//echo $content;die();
				break;
			case 'application/xmlWord.Document':    // Word 2003*/
			case 'application/vnd.openxmlformats-officedocument.wordprocessingml.document':    // ms office 2007
			case 'application/vnd.ms-word.document.macroenabled.12':
			case 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet':
			case 'application/vnd.ms-excel.sheet.macroenabled.12':
				// It seems easier to split the parent tags here
				$replace_tags = array(
					// Tables, lists don't go inside <w:p>
					'/<(ol|ul|table)( [^>]*)?>/'                    => '</w:t></w:r></w:p><$1$2>',
					'/<\/(ol|ul|table)>/'                           => '</$1><w:p><w:r><w:t>',
					// Fix for things other than text (newlines) inside table row
					'/<(td)( [^>]*)?>((?!<w:t>))(.*?)<\/td>[\s]*?/' => '<$1$2><w:t>$4</w:t></td>',
					// Remove extra whitespace
					'/<li([^>]*?)>[^:print:]*?(.*?)<\/li>/'         => '<li$1>$2</li>', // This doesn't get it all
					'/<w:t>[\s]+(.*?)<\/w:t>/'                      => '<w:t>$1</w:t>',
					// Remove spans with no attributes, linebreaks inside them cause problems
					'/<span>(.*?)<\/span>/'                         => '$1'
				);
				$content = preg_replace(array_keys($replace_tags), array_values($replace_tags), $content);

				/*
				In the case where you have something like <span><span></w:t><w:br/><w:t></span></span> (invalid - mismatched tags),
				it takes multiple runs to get rid of both spans.  So, loop.
				OO.o files have not yet been shown to have this problem.
				*/
				$count = $i = 0;
				do
				{
					$content = preg_replace('/<span>(.*?)<\/span>/', '$1', $content, -1, $count);
					$i++;
				}
				while($count > 0 && $i < 10);

				$doc = new DOMDocument();
				$xslt = new XSLTProcessor();
				$xslt_file = $mimetype == 'application/xml' ? 'wordml.xslt' : 'msoffice.xslt';
				$doc->load(EGW_INCLUDE_ROOT . '/api/templates/default/Merge/' . $xslt_file);
				$xslt->importStyleSheet($doc);
				break;
		}

		// XSLT transform known tags
		if($xslt)
		{
			// does NOT work with php 5.2.6: Catchable fatal error: argument 1 to transformToXml() must be of type DOMDocument
			//$element = new SimpleXMLelement($content);
			$element = new DOMDocument('1.0', 'utf-8');
			$result = $element->loadXML($content);
			if(!$result)
			{
				throw new Api\Exception('Unable to parse merged document for styles.  Check warnings in log for details.');
			}
			$content = $xslt->transformToXml($element);
//echo $content;die();
			// Word 2003 needs two declarations, add extra declaration back in
			if($mimetype == 'application/xml' && $mso_application_progid == 'Word.Document' && strpos($content, '<?xml') !== 0)
			{
				$content = '<?xml version="1.0" encoding="UTF-8" standalone="yes"?>' . $content;
			}
			// Validate
			/*
			$doc = new DOMDocument();
			$doc->loadXML($content);
			$doc->schemaValidate(*Schema (xsd) file*);
			*/
		}
	}

	/**
	 * Use a different mimetype.  Sets this.is_xml & this.line_feed
	 */
	private function apply_mimetype($mimetype, $document = '')
	{
		// fix application/msword mimetype for rtf files
		if($mimetype == 'application/msword' && strtolower(substr($document, -4)) == '.rtf')
		{
			$mimetype = 'application/rtf';
		}

		switch($mimetype)
		{
			case 'application/vnd.oasis.opendocument.text':        // open office
			case 'application/vnd.oasis.opendocument.spreadsheet':
			case 'application/vnd.oasis.opendocument.presentation':
			case 'application/vnd.oasis.opendocument.text-template':
			case 'application/vnd.oasis.opendocument.spreadsheet-template':
			case 'application/vnd.oasis.opendocument.presentation-template':
			case 'application/vnd.openxmlformats-officedocument.wordprocessingml.document':    // ms office 2007
			case 'application/vnd.ms-word.document.macroenabled.12':
			case 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet':
			case 'application/vnd.ms-excel.sheet.macroenabled.12':
			case 'application/xml':
			case 'text/xml':
			case 'text/html':
				$this->is_xml = true;
				break;
		}

		switch($mimetype)
		{
			case 'application/rtf':
			case 'text/rtf':
				$this->line_feed = '}\par \pard\plain{';
				break;
			case 'application/vnd.oasis.opendocument.text':
			case 'application/vnd.oasis.opendocument.presentation':
			case 'application/vnd.oasis.opendocument.text-template':
			case 'application/vnd.oasis.opendocument.presentation-template':
				$this->line_feed = '<text:line-break/>';
				break;
			case 'application/vnd.oasis.opendocument.spreadsheet':        // open office calc
			case 'application/vnd.oasis.opendocument.spreadsheet-template':
				$this->line_feed = '</text:p><text:p>';
				break;
			case 'application/xmlExcel.Sheet':    // Excel 2003
				$this->line_feed = '&#10;';
				break;
			case 'application/vnd.openxmlformats-officedocument.wordprocessingml.document':
			case 'application/vnd.ms-word.document.macroenabled.12':
			case 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet':
			case 'application/vnd.ms-excel.sheet.macroenabled.12':
				$this->line_feed = '</w:t></w:r></w:p><w:p><w:r><w:t>';
				break;
			case 'application/xml';
				$this->line_feed = '</w:t></w:r><w:r><w:br w:type="text-wrapping" w:clear="all"/></w:r><w:r><w:t>';
				break;
			case 'text/html':
				$this->line_feed = "<br/>";
				break;
			default:
				$this->line_feed = "\n";
		}
		return $mimetype;
	}

	/**
	 * Merges a given document with contact data
	 *
	 * @param string $_content
	 * @param array $ids array with contact id(s)
	 * @param string &$err error-message on error
	 * @param string $mimetype mimetype of complete document, eg. text/*, application/vnd.oasis.opendocument.text, application/rtf
	 * @param array $fix =null regular expression => replacement pairs eg. to fix garbled placeholders
	 * @param string $charset =null charset to override default set by mimetype or export charset
	 * @return string|boolean merged document or false on error
	 */
	public function &merge_string($_content, $ids, &$err, $mimetype, array $fix = null, $charset = null)
	{
		// performance optimization: if there's nothing looking like a placeholder, just return it without any processing
		if (empty($_content) || strpos($_content, '$$') === false && strpos($_content, '{{') === false &&
			($mimetype !== 'application/rtf' || strpos($_content, '\\{\\{') === false))
		{
			return $_content;
		}
		$ids = empty($ids) ? [] : (array)$ids;
		$matches = null;
		if($mimetype == 'application/xml' &&
			preg_match('/' . preg_quote('<?mso-application progid="', '/') . '([^"]+)' . preg_quote('"?>', '/') . '/', substr($_content, 0, 200), $matches))
		{
			$mso_application_progid = $matches[1];
		}
		else
		{
			$mso_application_progid = '';
		}
		// alternative syntax using double curly brackets (eg. {{cat_id}} instead $$cat_id$$),
		// aggressively removing all xml-tags e.g. Word adds within placeholders
		// Convert {{...}} to $$...$$, handling nested tags and preserving HTML inside IF blocks.
		// This prevents tables and other markup from being stripped if they are part of
		// an IF branch like {{IF ... ~ ... ~ <table>...</table>}}.
		$content = $_content;
		if (strpos($content, '{{') !== false)
		{
			$pattern_curly = '/{{[^{}]+}}/u';
			$guard = 0; // safety guard against pathological inputs
			while (preg_match($pattern_curly, $content) && $guard++ < 2000)
			{
				$content = preg_replace_callback($pattern_curly, function ($m)
				{
					$inner = substr($m[0], 2, -2);

					// Do NOT strip HTML for IF ... blocks – keep markup intact.
					// Nested {{...}} inside will be converted by later iterations.
					if (preg_match('/^\s*IF\s/i', $inner))
					{
						return '$$' . $inner . '$$';
					}

					// Simple placeholders / directives: strip any Word-inserted tags
					// so {{n_fn}} corrupted by Word styling still becomes $$n_fn$$.
					return '$$' . strip_tags($inner) . '$$';
				}, $content);
			}
		}
		// Handle escaped placeholder markers in RTF, they won't match when escaped
		if($mimetype == 'application/rtf')
		{
			$content = preg_replace('/\\\{\\\{([^\\}]+)\\\}\\\}/i', '$$\1$$', $content);
		}

		// make currently processed mimetype available to class methods;
		$this->mimetype = $this->apply_mimetype($mimetype);

		// fix garbled placeholders
		if($fix && is_array($fix))
		{
			$content = preg_replace(array_keys($fix), array_values($fix), $content);
			//die("<pre>".htmlspecialchars($content)."</pre>\n");
		}
		list($contentstart, $contentrepeat, $contentend) = preg_split('/\$\$pagerepeat\$\$/', $content, -1, PREG_SPLIT_NO_EMPTY) + [null,
																																	null,
																																	null];  //get differt parts of document, seperatet by Pagerepeat
		if($mimetype == 'text/plain' && $ids && count($ids) > 1)
		{
			// textdocuments are simple, they do not hold start and end, but they may have content before and after the $$pagerepeat$$ tag
			// header and footer should not hold any $$ tags; if we find $$ tags with the header, we assume it is the pagerepeatcontent
			$nohead = false;
			if(stripos($contentstart, '$$') !== false)
			{
				$nohead = true;
			}
			if($nohead)
			{
				$contentend = $contentrepeat;
				$contentrepeat = $contentstart;
				$contentstart = '';
			}

		}
		if(in_array($mimetype, array('application/vnd.oasis.opendocument.text',
									 'application/vnd.oasis.opendocument.text-template')) && count($ids) > 1)
		{
			if(strpos($content, '$$pagerepeat') === false)
			{
				//for odt files we have to split the content and add a style for page break to  the style area
				list($contentstart, $contentrepeat, $contentend) = preg_split('/office:body>/', $content, -1, PREG_SPLIT_NO_EMPTY);           //get differt parts of document, seperatet by Pagerepeat
				$contentstart = substr($contentstart, 0, strlen($contentstart) - 1);                                                          //remove "<"
				$contentrepeat = substr($contentrepeat, 0, strlen($contentrepeat) - 2);                                                       //remove "</";
				// need to add page-break style to the style list
				list($stylestart, $stylerepeat, $styleend) = preg_split('/<\/office:automatic-styles>/', $content, -1, PREG_SPLIT_NO_EMPTY);  //get differt parts of document style sheets
				$contentstart = $stylestart . '<style:style style:name="P200" style:family="paragraph" style:parent-style-name="Standard"><style:paragraph-properties fo:break-before="page"/></style:style></office:automatic-styles>';
				$contentstart .= '<office:body>';
				$contentend = '</office:body></office:document-content>';
			}
			else
			{
				// Template specifies where to repeat
				list($contentstart, $contentrepeat, $contentend) = preg_split('/\$\$pagerepeat\$\$/', $content, -1, PREG_SPLIT_NO_EMPTY);  //get different parts of document, seperated by pagerepeat
			}
		}
		if(in_array($mimetype, array('application/vnd.ms-word.document.macroenabled.12',
									 'application/vnd.openxmlformats-officedocument.wordprocessingml.document')) && count($ids) > 1)
		{
			//for Word 2007 XML files we have to split the content and add a style for page break to  the style area
			list($contentstart, $contentrepeat, $contentend) = preg_split('/w:body>/', $content, -1, PREG_SPLIT_NO_EMPTY);  //get differt parts of document, seperatet by Pagerepeat
			$contentstart = substr($contentstart, 0, strlen($contentstart) - 1);                                            //remove "</"
			$contentrepeat = substr($contentrepeat, 0, strlen($contentrepeat) - 2);                                         //remove "</";
			$contentstart .= '<w:body>';
			$contentend = '</w:body></w:document>';
		}
		list($Labelstart, $Labelrepeat, $Labeltend) = preg_split('/\$\$label\$\$/', $contentrepeat, -1, PREG_SPLIT_NO_EMPTY) + [null,
																																null,
																																null];  //get the label content
		preg_match_all('/\$\$labelplacement\$\$/', $contentrepeat, $countlables, PREG_SPLIT_NO_EMPTY);
		$countlables = count($countlables[0]);
		preg_replace('/\$\$labelplacement\$\$/', '', $Labelrepeat, 1);
		$lableprint = $countlables > 1;
		if(count($ids) > 1 && !$contentrepeat)
		{
			$err = lang('for more than one contact in a document use the tag pagerepeat!');
			$ret = false;
			return $ret;
		}
		if($this->report_memory_usage)
		{
			error_log(__METHOD__ . "(count(ids)=" . count($ids) . ") strlen(contentrepeat)=" . strlen($contentrepeat) . ', strlen(labelrepeat)=' . strlen($Labelrepeat));
		}

		if($contentrepeat)
		{
			$content_stream = fopen('php://temp', 'r+');
			fwrite($content_stream, $contentstart);
			$joiner = '';
			switch($mimetype)
			{
				case 'application/rtf':
				case 'text/rtf':
					$joiner = '\\par \\page\\pard\\plain';
					break;
				case 'application/vnd.oasis.opendocument.text':    // oo text
				case 'application/vnd.oasis.opendocument.spreadsheet':    // oo spreadsheet
				case 'application/vnd.oasis.opendocument.presentation':
				case 'application/vnd.oasis.opendocument.text-template':
				case 'application/vnd.oasis.opendocument.spreadsheet-template':
				case 'application/vnd.oasis.opendocument.presentation-template':
				case 'application/xml':
				case 'text/html':
				case 'text/csv':
					$joiner = '';
					break;
				case 'application/vnd.openxmlformats-officedocument.wordprocessingml.document':
				case 'application/vnd.ms-word.document.macroenabled.12':
				case 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet':
				case 'application/vnd.ms-excel.sheet.macroenabled.12':
					$joiner = '<w:br w:type="page" />';
					break;
				case 'text/plain':
					$joiner = "\r\n";
					break;
				default:
					$err = lang('%1 not implemented for %2!', '$$pagerepeat$$', $mimetype);
					$ret = false;
					return $ret;
			}
		}
		foreach((array)$ids as $n => $id)
		{
			if($contentrepeat)
			{
				$content = $contentrepeat;
			}   //content to repeat
			if($lableprint)
			{
				$content = $Labelrepeat;
			}

			// generate replacements; if exception is thrown, catch it set error message and return false
			try
			{
				if(!($replacements = $this->get_replacements($id, $content)))
				{
					$err = lang('Entry not found!');
					$ret = false;
					return $ret;
				}
			}
			catch (Api\Exception\WrongUserinput $e)
			{
				// if this returns with an exeption, something failed big time
				$err = $e->getMessage();
				$ret = false;
				return $ret;
			}
			if($this->report_memory_usage)
			{
				error_log(__METHOD__ . "() $n: $id " . Api\Vfs::hsize(memory_get_usage(true)));
			}
			// some general replacements: current user, date and time
			if(strpos($content, '$$user/') !== false && ($user = $GLOBALS['egw']->accounts->id2name($GLOBALS['egw_info']['user']['account_id'], 'person_id')))
			{
				$replacements += $this->contact_replacements($user, 'user', false, $content);
				$replacements['$$user/primary_group$$'] = $GLOBALS['egw']->accounts->id2name($GLOBALS['egw']->accounts->id2name($GLOBALS['egw_info']['user']['account_id'], 'account_primary_group'));
			}
			$replacements['$$date$$'] = Api\DateTime::to('now', true);
			$replacements['$$datetime$$'] = Api\DateTime::to('now');
			$replacements['$$time$$'] = Api\DateTime::to('now', false);

			$app = $this->get_app();
			$replacements += $this->share_placeholder($app, $id, '', $content);

			// does our extending class registered table-plugins AND document contains table tags
			if($this->table_plugins && preg_match_all('/\\$\\$table\\/([A-Za-z0-9_]+)\\$\\$(.*?)\\$\\$endtable\\$\\$/s', $content, $matches, PREG_SET_ORDER))
			{
				// process each table
				foreach($matches as $match)
				{
					$plugin = $match[1];    // plugin name
					$callback = $this->table_plugins[$plugin];
					$repeat = $match[2];    // line to repeat
					$repeats = '';
					if(isset($callback))
					{
						for($n = 0; ($row_replacements = $this->$callback($plugin, $id, $n, $repeat)); ++$n)
						{
							if($this->is_xml)
							{
								$row_replacements = str_replace(
									array('&', '&amp;amp;', '<', '>', "\r"),
									array('&amp;', '&amp;', '&lt;', '&gt;', ''),
									$row_replacements
								);
							}
							$_repeat = $this->process_commands($repeat, $row_replacements);
							$repeats .= $this->replace($_repeat, $row_replacements, $mimetype, $mso_application_progid);
						}
					}
					$content = str_replace($match[0], $repeats, $content);
				}
			}
			if($this->is_xml)
			{
				// Replace & with &amp; but don't touch other entities
				$replacements = preg_replace('/&(?![a-zA-Z]+;|#\d+;|#x[0-9a-fA-F]+;)/', '&amp;', $replacements);
				$replacements = str_replace(
					array('&amp;amp;', '<', '>', "\r"),
					array('&amp;', '&lt;', '&gt;', ''),
					$replacements
				);
			}
			$content = $this->replace($this->process_commands($content, $replacements), $replacements, $mimetype, $mso_application_progid, $charset);

			// remove not existing replacements (eg. from calendar array)
			if(strpos($content, '$$') !== null)
			{
				$content = preg_replace('/\$\$[a-z0-9_\/]+\$\$/i', '', $content);
			}
			if($contentrepeat)
			{
				fwrite($content_stream, ($n == 0 ? '' : $joiner) . $content);
			}
			if($lableprint)
			{
				$contentrep[is_array($id) ? implode(':', $id) : $id] = $content;
			}
		}
		if($Labelrepeat)
		{
			$countpage = 0;
			$count = 0;
			$contentrepeatpages[$countpage] = $Labelstart . $Labeltend;

			foreach($contentrep as $Label)
			{
				$contentrepeatpages[$countpage] = preg_replace('/\$\$labelplacement\$\$/', $Label, $contentrepeatpages[$countpage], 1);
				$count = $count + 1;
				if(($count % $countlables) == 0 && count($contentrep) > $count)  //new page
				{
					$countpage = $countpage + 1;
					$contentrepeatpages[$countpage] = $Labelstart . $Labeltend;
				}
			}
			$contentrepeatpages[$countpage] = preg_replace('/\$\$labelplacement\$\$/', '', $contentrepeatpages[$countpage], -1);  //clean empty fields

			switch($mimetype)
			{
				case 'application/rtf':
				case 'text/rtf':
					$ret = $contentstart . implode('\\par \\page\\pard\\plain', $contentrepeatpages) . $contentend;
					break;
				case 'application/vnd.oasis.opendocument.text':
				case 'application/vnd.oasis.opendocument.presentation':
				case 'application/vnd.oasis.opendocument.text-template':
				case 'application/vnd.oasis.opendocument.presentation-template':
					$ret = $contentstart . implode('<text:line-break />', $contentrepeatpages) . $contentend;
					break;
				case 'application/vnd.oasis.opendocument.spreadsheet':
				case 'application/vnd.oasis.opendocument.spreadsheet-template':
					$ret = $contentstart . implode('</text:p><text:p>', $contentrepeatpages) . $contentend;
					break;
				case 'application/vnd.openxmlformats-officedocument.wordprocessingml.document':
				case 'application/vnd.ms-word.document.macroenabled.12':
				case 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet':
				case 'application/vnd.ms-excel.sheet.macroenabled.12':
					$ret = $contentstart . implode('<w:br w:type="page" />', $contentrepeatpages) . $contentend;
					break;
				case 'text/plain':
					$ret = $contentstart . implode("\r\n", $contentrep) . $contentend;
					break;
				default:
					$err = lang('%1 not implemented for %2!', '$$labelplacement$$', $mimetype);
					$ret = false;
			}
			return $ret;
		}

		if($contentrepeat)
		{
			fwrite($content_stream, $contentend);
			rewind($content_stream);
			$content = stream_get_contents($content_stream);
		}
		if($this->report_memory_usage)
		{
			error_log(__METHOD__ . "() returning " . Api\Vfs::hsize(memory_get_peak_usage(true)));
		}

		return $content;
	}

	/**
	 * Replace placeholders in $content of $mimetype with $replacements
	 *
	 * @param string $content
	 * @param array $replacements name => replacement pairs
	 * @param string $mimetype mimetype of content
	 * @param string $mso_application_progid ='' MS Office 2003: 'Excel.Sheet' or 'Word.Document'
	 * @param string $charset =null charset to override default set by mimetype or export charset
	 * @return string
	 */
	protected function replace($content, array $replacements, $mimetype, $mso_application_progid = '', $charset = null)
	{
		switch($mimetype)
		{
			case 'application/vnd.oasis.opendocument.text':        // open office
			case 'application/vnd.oasis.opendocument.spreadsheet':
			case 'application/vnd.oasis.opendocument.presentation':
			case 'application/vnd.oasis.opendocument.text-template':
			case 'application/vnd.oasis.opendocument.spreadsheet-template':
			case 'application/vnd.oasis.opendocument.presentation-template':
			case 'application/vnd.openxmlformats-officedocument.wordprocessingml.document':    // ms office 2007
			case 'application/vnd.ms-word.document.macroenabled.12':
			case 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet':
			case 'application/vnd.ms-excel.sheet.macroenabled.12':
			case 'application/xml':
			case 'text/xml':
				$is_xml = true;
				$charset = 'utf-8';    // xml files --> always use utf-8
				break;

			case 'application/rtf':
			case 'text/rtf':
				$charset = 'iso-8859-1';    // rtf seems to user iso-8859-1 or equivalent windows charset, not utf-8
				break;

			case 'text/html':
				$is_xml = true;
				$matches = null;
				if(preg_match('/<meta http-equiv="content-type".*charset=([^;"]+)/i', $content, $matches))
				{
					$charset = $matches[1];
				}
				elseif(empty($charset))
				{
					$charset = 'utf-8';
				}
				break;

			default:    // div. text files --> use our export-charset, defined in addressbook prefs
				if(empty($charset))
				{
					$charset = $this->contacts->prefs['csv_charset'];
				}
				break;
		}
		//error_log(__METHOD__."('$document', ... ,$mimetype) --> $charset (egw=".Api\Translation::charset().', export='.$this->contacts->prefs['csv_charset'].')');

		// do we need to convert charset
		if($charset && $charset != Api\Translation::charset())
		{
			$replacements = Api\Translation::convert($replacements, Api\Translation::charset(), $charset);
		}

		// Date only placeholders for timestamps
		if(is_array($this->date_fields))
		{
			foreach($this->date_fields as $field)
			{
				if(($value = $replacements['$$' . $field . '$$'] ?? null))
				{
					$time = Api\DateTime::createFromFormat('+' . Api\DateTime::$user_dateformat . '*' . Api\DateTime::$user_timeformat . '*', $value);
					$replacements['$$' . $field . '/date$$'] = $time ? $time->format(Api\DateTime::$user_dateformat) : '';
					$replacements['$$' . $field . '/time$$'] = $time ? $time->format(Api\DateTime::$user_timeformat) : '';
				}
			}
		}
		// Numeric fields
		$names = array();

		// Tags we can replace with the target document's version
		$replace_tags = array();
		// only keep tags, if we have xsl extension available
		if(class_exists('XSLTProcessor') && class_exists('DOMDocument') && $this->parse_html_styles)
		{
			switch($mimetype . $mso_application_progid)
			{
				case 'text/html':
					$replace_tags = array(
						'<b>', '<strong>', '<i>', '<em>', '<u>', '<span>', '<ol>', '<ul>', '<li>',
						'<table>', '<tr>', '<td>', '<a>', '<style>', '<img>',
					);
					break;
				case 'application/vnd.oasis.opendocument.text':        // open office
				case 'application/vnd.oasis.opendocument.spreadsheet':
				case 'application/vnd.oasis.opendocument.presentation':
				case 'application/vnd.oasis.opendocument.text-template':
				case 'application/vnd.oasis.opendocument.spreadsheet-template':
				case 'application/vnd.oasis.opendocument.presentation-template':
					$replace_tags = array(
						'<b>', '<strong>', '<i>', '<em>', '<u>', '<span>', '<ol>', '<ul>', '<li>',
						'<table>', '<tr>', '<td>', '<a>',
					);
					break;
				case 'application/xmlWord.Document':    // Word 2003*/
				case 'application/vnd.openxmlformats-officedocument.wordprocessingml.document':    // ms office 2007
				case 'application/vnd.ms-word.document.macroenabled.12':
				case 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet':
				case 'application/vnd.ms-excel.sheet.macroenabled.12':
					$replace_tags = array(
						'<b>', '<strong>', '<i>', '<em>', '<u>', '<span>', '<ol>', '<ul>', '<li>',
						'<table>', '<tr>', '<td>',
					);
					break;
			}
		}

		if(!empty($is_xml))    // zip'ed xml document (eg. OO)
		{
			// clean replacements from array values and html or html-entities, which mess up xml
			foreach($replacements as $name => &$value)
			{
				// set unresolved array values to empty string
				if(is_array($value))
				{
					$value = '';
					continue;
				}
				// decode html entities back to utf-8
				if(is_string($value) && (strpos($value, '&') !== false) && $this->parse_html_styles)
				{
					$value = html_entity_decode($value, ENT_QUOTES, $charset);

					// remove all non-decodable entities
					if(strpos($value, '&') !== false)
					{
						//$value = preg_replace('/&[^; ]+;/', '', $value);
					}
				}
				if(!$this->parse_html_styles)
				{
					// Encode special chars so they don't break the file
					//$value = htmlspecialchars($value, ENT_NOQUOTES);
					strip_tags(str_replace(
								   array("\r", '<p>', "</p>\n", '</p>', '<div>', '</div>', '<br />'),
								   array('', '', "\n", "\n", '', "\n", "\n"), $value
							   ), implode('', $replace_tags)
					);
				}
				else
				{
					if(is_string($value) && (strpos($value, '<') !== false))
					{
						// Clean HTML, if it's being kept
						if($replace_tags && extension_loaded('tidy'))
						{
							$tidy = new tidy();
							$cleaned = $tidy->repairString($value, self::$tidy_config, 'utf8');
							// Found errors. Strip it all so there's some output
							if($tidy->getStatus() == 2)
							{
								error_log($tidy->errorBuffer);
								$value = strip_tags($value);
							}
							else
							{
								// Strip some specific stuff to avoid the extra new lines
								$value = str_replace(["<html>\n", '<html>', "<head>\n<title></title>\n</head>\n",
													  "<body>\n", '<body>',
													  "</body>\n", "</html>\n", '</html>'], '', $cleaned);
							}
						}
						// replace </p> and <br /> with CRLF (remove <p> and CRLF)
						$value = strip_tags(str_replace(array("\r", '<p>', "</p>\n", '</p>', '<div>', '</div>',
															  '<br />'),
														array('', '', "\n", "\n", '', "\n", "\n"), $value
											),
											implode('', $replace_tags)
						);

						// Change <tag>...\r\n</tag> to <tag>...</tag>\r\n or simplistic line break below will mangle it
						// Loop to catch things like <b><span>Break:\r\n</span></b>
						if($mso_application_progid)
						{
							$count = $i = 0;
							do
							{
								$value = preg_replace('/<(b|strong|i|em|u|span)\b([^>]*?)>(.*?)' . "\r\n" . '<\/\1>/u', '<$1$2>$3</$1>' . "\r\n", $value, -1, $count);
								$i++;
							}
							while($count > 0 && $i < 10); // Limit of 10 chosen arbitrarily just in case
						}
					}
				}
				// replace all control chars (C0+C1) but CR (\015), LF (\012) and TAB (\011) (eg. vertical tabulators) with space
				// as they are not allowed in xml
				$value = preg_replace('/[\000-\010\013\014\016-\037\177-\237\x{FFF0}-\x{FFFD}]/u', ' ', $value);
				if(is_numeric($value) && $name != '$$user/account_id$$') // account_id causes problems with the preg_replace below
				{
					$names[] = preg_quote($name, '/');
				}
			}

			// Look for numbers, set their value if needed
			if(property_exists($this, 'numeric_fields') || count($names))
			{
				foreach($this->numeric_fields as $fieldname)
				{
					if(!array_key_exists($this->prefix("", $fieldname, '$'), $replacements))
					{
						continue;
					}
					$names[] = preg_quote($this->prefix("", $fieldname, '$'), '/');
					$raw_placeholder = $this->prefix("", $fieldname . '_-raw-', '$');
					if(!array_key_exists($raw_placeholder, $replacements))
					{
						$replacements[$raw_placeholder] = $replacements[$this->prefix("", $fieldname, '$')];
						$replacements[$this->prefix("", $fieldname, '$')] = self::number_format($replacements[$raw_placeholder], 2, $this->mimetype);

						// Check for decimal places formatter
						$format_matches = [];
						preg_match_all("\$($fieldname):(?<decimals>[\d])\$", $content, $format_matches);
						foreach($format_matches['decimals'] as $decimal)
						{
							$replacements[$this->prefix("", $fieldname . ':' . $decimal, '$')] = self::number_format($replacements[$raw_placeholder], $decimal, $this->mimetype);
						}
					}
				}
				$this->format_spreadsheet_numbers($content, $names, $mimetype . $mso_application_progid);
			}

			// Look for dates, set their value if needed
			if($this->date_fields || count($names))
			{
				$names = array();
				foreach((array)$this->date_fields as $fieldname)
				{
					$names[] = $fieldname;
				}
				$this->format_spreadsheet_dates($content, $names, $replacements, $mimetype . $mso_application_progid);
			}

			// replace CRLF with linebreak tag of given type

			// now decode &, < and >, which need to be encoded as entities in xml
			// Check for encoded >< getting double-encoded
			if($this->parse_html_styles)
			{
				$replacements = str_replace(
					array('&', "\r", "\n", '&amp;amp;', '&amp;lt;', '&amp;gt;', '&amp;nbsp;'),
					array('&amp;', '', $this->line_feed, '&amp;', '&lt;', '&gt;', ' '),
					$replacements
				);
			}
			else
			{
				// Need to at least handle new lines, or it'll be run together on one line
				$replacements = str_replace(
					array("\r", "\n", '&amp;amp;'),
					array('', $this->line_feed, '&amp;'),
					$replacements
				);
			}
		}
		else
		{
			// HTML into non-XML (plaintext template)
			foreach($replacements as $name => &$value)
			{
				// set unresolved array values to empty string
				if(is_array($value))
				{
					$value = '';
					continue;
				}
				$value = html_entity_decode($value, ENT_QUOTES, $charset);
			}
		}
		if($mimetype == 'application/x-yaml')
		{
			$content = preg_replace_callback('/^( +)([^$\n]*)(\$\$.+?\$\$)/m', function ($matches) use ($replacements)
			{
				// allow with {{name/replace/with}} syntax to replace eg. commas with linebreaks: "{{name/, */\n}}"
				$parts = null;
				if(preg_match('|^\$\$([^/]+)/([^/]+)/([^$]*)\$\$$|', $matches[3], $parts) && isset($replacements['$$' . $parts[1] . '$$']))
				{
					$replacement =& $replacements['$$' . $parts[1] . '$$'];
					$replacement = preg_replace('/' . $parts[2] . '/', strtr($parts[3], array(
						'\\n' => "\n", '\\r' => "\r", '\\t' => "\t", '\\v' => "\v", '\\\\' => '\\', '\\f' => "\f",
					)),                         $replacement
					);
				}
				else
				{
					$replacement =& $replacements[$matches[3]];
				}
				// replacement with multiple lines --> add same number of space as before placeholder
				if(isset($replacement))
				{
					return $matches[1] . $matches[2] . implode("\n" . $matches[1], preg_split("/\r?\n/", $replacement));
				}
				return $matches[0];    // regular replacement below
			},                               $content);
		}
		return str_replace(array_keys($replacements), array_values($replacements), $content);
	}

	/**
	 * Convert numeric values in spreadsheets into actual numeric values
	 */
	protected function format_spreadsheet_numbers(&$content, $names, $mimetype)
	{
		foreach($this->numeric_fields as $fieldname)
		{
			$names[] = preg_quote($fieldname, '/');
		}
		switch($mimetype)
		{
			case 'application/vnd.oasis.opendocument.spreadsheet':        // open office calc
			case 'application/vnd.oasis.opendocument.spreadsheet-template':
			$format = '/<table:table-cell([^>]+?)office:value-type="[^"]+"([^>]*?)(?:calcext:value-type="[^"]+")?>.?<([^ >]+?)( ?[^>]*?)>(' . implode('|', $names) . ')<\/\3>.?<\/table:table-cell>/s';
			$replacement = '<table:table-cell$1office:value-type="float" calcext:value-type="float" office:value="$6"$2><$3$4>$5</$3></table:table-cell>';
				break;
			case 'application/vnd.oasis.opendocument.text':        // tables in open office writer
			case 'application/vnd.oasis.opendocument.presentation':
			case 'application/vnd.oasis.opendocument.text-template':
			case 'application/vnd.oasis.opendocument.presentation-template':
			$format = '/<table:table-cell([^>]+?)office:value-type="[^"]+"([^>]*?)>.?<([^ >]+?)( ?[^>]*?)>(' . implode('|', $names) . ')<\/\3>.?<\/table:table-cell>/s';
			$replacement = '<table:table-cell$1office:value-type="float" calcext:value-type="float" office:value="$6"$2><text:p $4>$5</text:p></table:table-cell>';
				break;
			case 'application/vnd.oasis.opendocument.text':        // open office writer
			case 'application/xmlExcel.Sheet':    // Excel 2003
				$format = '/' . preg_quote('<Data ss:Type="String">', '/') . '(' . implode('|', $names) . ')' . preg_quote('</Data>', '/') . '/';
				$replacement = '<Data ss:Type="Number">$1</Data>';

				break;
		}
		if(!empty($format) && $names)
		{
			// Use raw value instead of formatted value for spreadsheets (when present), but don't interfere otherwise
			$callback = function ($matches) use ($replacement)
			{
				if($matches[5] && ($fieldname = substr($matches[5], 2, -2)) && in_array($fieldname, $this->numeric_fields))
				{
					$matches[6] = $this->prefix("", $fieldname . '_-raw-', '$');
				}
				else
				{
					$matches[6] = $matches[5];
				}
				return str_replace(['$0', '$1', '$2', '$3', '$4', '$5', '$6'], $matches, $replacement);
			};
			// Dealing with backtrack limit per AmigoJack 10-Jul-2010 comment on php.net preg-replace docs
			do
			{
				$result = preg_replace_callback($format, $callback, $content, -1);
			}
				// try to increase/double pcre.backtrack_limit failure
			while(preg_last_error() == PREG_BACKTRACK_LIMIT_ERROR && self::increase_backtrack_limit());

			if($result)
			{
				$content = $result;
			}  // On failure $result would be NULL
		}
	}

	/**
	 * Increase/double prce.backtrack_limit up to 1/4 of memory_limit
	 *
	 * @return boolean true: backtrack_limit increased, may try again, false limit already to high
	 */
	protected static function increase_backtrack_limit()
	{
		static $backtrack_limit = null, $memory_limit = null;
		if(!isset($backtrack_limit))
		{
			$backtrack_limit = ini_get('pcre.backtrack_limit');
		}
		if(!isset($memory_limit))
		{
			$memory_limit = ini_get('memory_limit');
			switch(strtoupper(substr($memory_limit, -1)))
			{
				case 'G':
					$memory_limit *= 1024;
				case 'M':
					$memory_limit *= 1024;
				case 'K':
					$memory_limit *= 1024;
			}
		}
		if($backtrack_limit < $memory_limit / 8)
		{
			ini_set('pcre.backtrack_limit', $backtrack_limit *= 2);
			return true;
		}
		error_log("pcre.backtrack_limit exceeded @ $backtrack_limit, some cells left as text.");
		return false;
	}

	/**
	 * Convert date / timestamp values in spreadsheets into actual date / timestamp values
	 */
	protected function format_spreadsheet_dates(&$content, $names, &$values, $mimetype)
	{
		if(!in_array($mimetype, array(
			'application/vnd.oasis.opendocument.spreadsheet',        // open office calc
			'application/xmlExcel.Sheet',                    // Excel 2003
			//'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet'//Excel WTF
		)))
		{
			return;
		}

		// Some different formats dates could be in, depending what they've been through
		$formats = array(
			'!' . Api\DateTime::$user_dateformat . ' ' . Api\DateTime::$user_timeformat . ':s',
			'!' . Api\DateTime::$user_dateformat . '*' . Api\DateTime::$user_timeformat . ':s',
			'!' . Api\DateTime::$user_dateformat . '* ' . Api\DateTime::$user_timeformat,
			'!' . Api\DateTime::$user_dateformat . '*',
			'!' . Api\DateTime::$user_dateformat,
			'!Y-m-d\TH:i:s'
		);

		// Properly format values for spreadsheet
		foreach($names as $idx => &$field)
		{
			$key = '$$' . $field . '$$';
			$field = preg_quote($field, '/');
			if (!empty($values[$key]))
			{
				$date = Api\DateTime::createFromUserFormat($values[$key]);
				if($mimetype == 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet' ||
					$mimetype == 'application/vnd.ms-excel.sheet.macroenabled.12')//Excel WTF
				{
					$interval = $date->diff(new Api\DateTime('1900-01-00 0:00'));
					$values[$key] = $interval->format('%a') + 1;// 1900-02-29 did not exist
					// 1440 minutes in a day - fractional part
					$values[$key] += ($date->format('H') * 60 + $date->format('i')) / 1440;
				}
				else
				{
					$values[$key] = date('Y-m-d\TH:i:s', Api\DateTime::to($date, 'ts'));
				}
			}
			else
			{
				unset($names[$idx]);
			}
		}

		switch($mimetype)
		{
			case 'application/vnd.oasis.opendocument.spreadsheet':        // open office calc
				// Removing these forces calc to respect our set value-type
				$content = str_ireplace('calcext:value-type="string"', '', $content);

				$format = '/<table:table-cell([^>]+?)office:value-type="[^"]+"([^>]*?)>.?<([a-z].*?)[^>]*>\$\$(' . implode('|', $names) . ')\$\$<\/\3>.?<\/table:table-cell>/s';
				$replacement = '<table:table-cell$1office:value-type="date" calcext:value-type="date" office:date-value="\$\$$4\$\$"$2><$3>\$\$$4\$\$</$3></table:table-cell>';
				break;
			case 'application/xmlExcel.Sheet':    // Excel 2003
				$format = '/' . preg_quote('<Data ss:Type="String">', '/') . '..(' . implode('|', $names) . ')..' . preg_quote('</Data>', '/') . '/';
				$replacement = '<Data ss:Type="DateTime">\$\$$1\$\$</Data>';

				break;
			case 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet':
			case 'application/vnd.ms-excel.sheet.macroenabled.12':
				break;
		}
		if($format && $names)
		{
			// Dealing with backtrack limit per AmigoJack 10-Jul-2010 comment on php.net preg-replace docs
			do
			{
				$result = preg_replace($format, $replacement, $content, -1);
			}
				// try to increase/double pcre.backtrack_limit failure
			while(preg_last_error() == PREG_BACKTRACK_LIMIT_ERROR && self::increase_backtrack_limit());

			if($result)
			{
				$content = $result;
			}  // On failure $result would be NULL
		}
	}

	/**
	 * Expand link_to custom fields with the merge replacements from the app
	 * but only if the template uses them.
	 * We also do other custom field processing here
	 */
	public function cf_link_to_expand($values, $content, &$replacements, $app = null)
	{
		if($app == null)
		{
			$app = str_replace('_merge', '', get_class($this));
		}
		$cfs = Api\Storage\Customfields::get($app);

		// Custom field processing
		foreach($cfs as $fieldname => $field_data)
		{
			switch($field_data['type'])
			{
				case 'float':
				case 'int':
				$this->numeric_fields[] = "#{$fieldname}";
					break;
				case 'date':
				case 'date-time':
				$this->date_fields[] = "#{$fieldname}";
			}
		}

		// Cache, in case more than one sub-placeholder is used
		$app_replacements = array();

		// Custom field placeholders look like {{#name}}
		// Placeholders that need expanded will look like {{#name/placeholder}}
		$matches = null;
		preg_match_all('/\${2}(([^\/#]*?\/)?)#([^$\/]+)\/(.*?)[$}]{2}/', $content, $matches);
		list($placeholders, , , $cf, $sub) = $matches;

		// Collect any used custom fields from entries so you can do
		// {{#other_app/#other_app_cf/n_fn}}
		$expand_sub_cfs = [];
		foreach($sub as $index => $cf_sub)
		{
			if(str_starts_with($cf_sub, '#'))
			{
				$expand_sub_cfs[$cf[$index]] = (isset($expand_sub_cfs[$cf[$index]]) ? $expand_sub_cfs[$cf[$index]] : '') .
					'$$' . $cf_sub . '$$ ';
			}
		}

		foreach($cf as $index => $field)
		{
			if(isset($cfs[$field]))
			{
				// Select-account can be multiple
				$is_multiple = str_starts_with($cfs[$field]['type'], 'select') && (int)$cfs[$field]['rows'] > 1;
				$replaced = [];
				foreach($is_multiple ? explode(',', $values['#' . $field]) : [$values['#' . $field]] as $value)
				{
					if(in_array($cfs[$field]['type'], array_keys($GLOBALS['egw_info']['apps'])))
					{
						$field_app = $cfs[$field]['type'];
					}
					else
					{
						if($cfs[$field]['type'] == 'api-accounts' || $cfs[$field]['type'] == 'select-account')
						{
							// Special case for api-accounts -> contact
							$field_app = 'addressbook';
							$account = $GLOBALS['egw']->accounts->read($value);
							$app_replacements[$field] = $this->contact_replacements($account['person_id']);
						}
						else
						{
							if(($list = explode('-', $cfs[$field]['type'])) && in_array($list[0], array_keys($GLOBALS['egw_info']['apps'])))
							{
								// Sub-type - use app
								$field_app = $list[0];
							}
							else
							{
								continue;
							}
						}
					}

					// Get replacements for that application
					if(!isset($app_replacements[$field]))
					{
						// If we send the real content it can result in infinite loop of lookups
						// so we send only the used fields
						$content = $expand_sub_cfs[$field] ?? $matches[0][$index];
						$app_replacements[$field] = $this->get_app_replacements($field_app, $value, $content);
					}
					$replaced[] = $app_replacements[$field]['$$' . $sub[$index] . '$$'] ?? '';
				}
				$replacements[$placeholders[$index]] = join(', ', $replaced) ?? '';
			}
			else
			{
				if(isset($cfs[$field]) && ($cfs[$field]['type'] == 'date' || $cfs[$field]['type'] == 'date-time'))
				{
					$this->date_fields[] = '#' . $field;
				}
			}
		}
	}

	/**
	 * Figure out which app we're running as
	 *
	 * @return string
	 */
	protected function get_app()
	{
		switch($class=get_class($this))
		{
			case 'EGroupware\Api\Contacts\Merge':
				$app = 'addressbook';
				break;
			default:
				if (str_starts_with($class, 'EGroupware\\'))
				{
					$app = strtolower(explode('\\', $class)[1] ?? '');
				}
				else
				{
					$app = str_replace('_merge', '', $class);
				}
				if(!in_array($app, array_keys($GLOBALS['egw_info']['apps'] ?? [])))
				{
					$app = false;
				}
				break;

		}

		return $app;
	}

	/**
	 * Get the correct class for the given app
	 *
	 * @param $appname
	 */
	public static function get_app_class($appname)
	{
		$classname = "{$appname}_merge";
		if(class_exists($classname) && is_subclass_of($classname, 'EGroupware\\Api\\Storage\\Merge'))
		{
			$document_merge = new $classname();
		}
		elseif(($classname = '\EGroupware\\' . ucfirst($appname) . '\Merge') && class_exists($classname) && is_subclass_of($classname, 'EGroupware\\Api\\Storage\\Merge'))
		{
			$document_merge = new $classname();
		}
		else
		{
			$document_merge = new Api\Contacts\Merge();
		}
		return $document_merge;
	}

	/**
	 * Get the replacements for any entry specified by app & id
	 *
	 * @param string $app
	 * @param string $id
	 * @param string $content
	 * @return array
	 */
	public function get_app_replacements($app, $id, $content, $prefix = '')
	{
		$replacements = array();
		if(!$app || !$id || !$content)
		{
			return $replacements;
		}
		if($app == 'addressbook')
		{
			return $this->contact_replacements($id, $prefix, false, $content);
		}

		try
		{
			$class = $this->get_app_class($app);
			$method = $app . '_replacements';
			if(method_exists($class, $method))
			{
				$replacements = $class->$method($id, $prefix, $content);
			}
			else
			{
				$replacements = $class->get_replacements($id, $content);
			}
		}
		catch (\Exception $e)
		{
			// Don't break merge, just log it
			error_log($e->getMessage());
		}
		return $replacements ?: [];
	}

	/**
	 * Prefix a placeholder, taking care of $$ or {{}} markers
	 *
	 * @param string $prefix Placeholder prefix
	 * @param string $placeholder Placeholder, with or without {{...}} or $$...$$ markers
	 * @param null|string $wrap "{" or "$" to add markers, omit to exclude markers
	 * @return string
	 */
	protected function prefix($prefix, $placeholder, $wrap = null)
	{
		$marker = ['', ''];
		if($placeholder && $placeholder[0] == '{' && is_null($wrap) || $wrap && $wrap[0] == '{')
		{
			$marker = ['{{', '}}'];
		}
		elseif($placeholder && $placeholder[0] == '$' && is_null($wrap) || $wrap && $wrap[0] == '$')
		{
			$marker = ['$$', '$$'];
		}

		$placeholder = str_replace(['{{', '}}', '$$'], '', $placeholder);
		return $marker[0] . ($prefix ? $prefix . '/' : '') . $placeholder . $marker[1];
	}

	/**
	 * Process special flags, such as IF or NELF
	 *
	 * @param string content Text to be examined and changed
	 * @param array replacements array of markers => replacement
	 *
	 * @return string changed content
	 */
	private function process_commands($content, $replacements)
	{
		if(strpos($content, '$$IF') !== false)
		{    //Example use to use: $$IF n_prefix~Herr~Sehr geehrter~Sehr geehrte$$
			$this->replacements = $replacements;
			$content = preg_replace_callback( '/\$\$IF ([#0-9a-z_\/-]+)~(.*?)~(.*?)~(.*?)\$\$/ims', array($this,
																									  'replace_callback'), $content);
			unset($this->replacements);
		}
		if(strpos($content, '$$NELF') !== false)
		{    //Example: $$NEPBR org_unit$$ sets a LF and value of org_unit, only if there is a value
			$this->replacements = $replacements;
			$content = preg_replace_callback('/\$\$NELF ([#0-9a-z_\/-]+)\$\$/imU', array($this,
																						 'replace_callback'), $content);
			unset($this->replacements);
		}
		if(strpos($content, '$$NENVLF') !== false)
		{    //Example: $$NEPBRNV org_unit$$ sets only a LF if there is a value for org_units, but did not add any value
			$this->replacements = $replacements;
			$content = preg_replace_callback('/\$\$NENVLF ([#0-9a-z_\/-]+)\$\$/imU', array($this,
																						   'replace_callback'), $content);
			unset($this->replacements);
		}
		if(strpos($content, '$$LETTERPREFIX$$') !== false)
		{    //Example use to use: $$LETTERPREFIX$$
			$LETTERPREFIXCUSTOM = '$$LETTERPREFIXCUSTOM n_prefix title n_family$$';
			$content = str_replace('$$LETTERPREFIX$$', $LETTERPREFIXCUSTOM, $content);
		}
		if(strpos($content, '$$LETTERPREFIXCUSTOM') !== false)
		{    //Example use to use for a custom Letter Prefix: $$LETTERPREFIX n_prefix title n_family$$
			$this->replacements = $replacements;
			$content = preg_replace_callback('/\$\$LETTERPREFIXCUSTOM ([#0-9a-z_-]+)(.*)\$\$/imU', array($this,
																										 'replace_callback'), $content);
			unset($this->replacements);
		}
		return $content;
	}

	/**
	 * Callback for preg_replace to process $$IF
	 *
	 * @param array $param
	 * @return string
	 */
	private function replace_callback($param)
	{
		// If THEN / ELSE are bare placeholder names, wrap them so they survive into replace()
		if (!empty($param[4]) && array_key_exists('$$' . $param[4] . '$$', $this->replacements))
		{
			$param[4] = '$$' . $param[4] . '$$';
		}
		if (!empty($param[3]) && array_key_exists('$$' . $param[3] . '$$', $this->replacements))
		{
			$param[3] = '$$' . $param[3] . '$$';
		}

		// --- NEW: allow placeholder(s) inside the IF compare value (2nd arg) ---
		// Examples:
		//   {{IF city~{{billing_city}}~...~...}}
		//   {{IF n_prefix~{{user/n_prefix}}~...~...}}
		$compare_raw = $param[2] ?? '';

		// Special-case: EMPTY (original behavior)
		$is_empty_check = (strpos($param[0], '$$IF') === 0 && (trim($compare_raw) === 'EMPTY' || $compare_raw === ''));

		if (!$is_empty_check)
		{
			// If the compare value is itself a placeholder name without $$...$$,
			// look it up directly.
			if (isset($this->replacements['$$' . $compare_raw . '$$']))
			{
				$compare_raw = $this->replacements['$$' . $compare_raw . '$$'];
			}
			// If the compare value contains $$placeholders$$, expand them now.
			if (strpos($compare_raw, '$$') !== false)
			{
				$compare_raw = str_replace(array_keys($this->replacements), array_values($this->replacements), $compare_raw);
			}
		}

		$pattern = $is_empty_check ? '/^$/' : '/' . preg_quote($compare_raw, '/') . '/';

		$replace = preg_match(
			$pattern,
			$this->replacements['$$' . $param[1] . '$$'] ?? ''
		) ? ($param[3] ?? null) : ($param[4] ?? null);

		$LF = $this->line_feed;

		if(strpos($param[0], '$$NELF') === 0)
		{    //sets a Pagebreak and value, only if the field has a value
			if(!empty($this->replacements['$$' . $param[1] . '$$']))
			{
				$replace = $LF . '$$' . $param[1] . '$$';
			}
		}
		if(strpos($param[0], '$$NENVLF') === 0)
		{    //sets a Pagebreak without any value, only if the field has a value
			if(!empty($this->replacements['$$' . $param[1] . '$$']))
			{
				$replace = $LF;
			}
		}
		if(strpos($param[0], '$$LETTERPREFIXCUSTOM') === 0)
		{    //sets a Letterprefix
			$replaceprefixsort = array();
			$replaceprefix = explode(' ', substr($param[0], 21, -2));
			foreach($replaceprefix as $nameprefix)
			{
				if(!empty($this->replacements['$$' . $nameprefix . '$$']))
				{
					$replaceprefixsort[] = '$$' . $nameprefix . '$$';
				}
			}
			$replace = implode(' ', $replaceprefixsort);
		}
		return $replace;
	}

	/**
	 * Download document merged with contact(s)
	 *
	 * Uses the Collabora conversion API to convert the file to a different format
	 * @see https://sdk.collaboraonline.com/docs/conversion_api.html

	 * @param string $document vfs-path of document
	 * @param array $ids array with contact id(s)
	 * @param string $name ='' name to use for downloaded document
	 * @param string $dirs comma or whitespace separated directories, used if $document is a relative path
	 * @param string $convert_to = '' extension to convert to eg. 'pdf' or null to NOT convert
	 * @return string with error-message on error, otherwise it does NOT return
	 */
	public function download($document, $ids, $name = '', $dirs = '', $convert_to = null)
	{
		$result = $this->merge_file($document, $ids, $name, $dirs, $header);

		if (is_file($result) && is_readable($result))
		{
			if ($convert_to && class_exists('EGroupware\\Collabora\\Conversion'))
			{
				$convert = new Conversion();
				if (!$convert->convert($result, $converted, $convert_to, $error_msg, false))
				{
					return $error_msg;
				}
				$header = [
					'name' => pathinfo($name, PATHINFO_FILENAME).'.'.$convert_to,
					'mime' => Api\MimeMagic::ext2mime($convert_to),
					'filesize' => filesize($converted),
				];
				$result = $converted;
			}
			Api\Header\Content::type($header['name'], $header['mime'], $header['filesize']);
			readfile($result);

			// run egw destructor now explicit, in case a (notification) email is send via Egw::on_shutdown(),
			// as stream-wrappers used by Horde Smtp fail when PHP is already in destruction
			$GLOBALS['egw']->__destruct();
			exit;
		}

		return $result;
	}

	/**
	 * Merge the IDs into the document, puts the document into the output buffer
	 *
	 * @param string $document vfs-path of document
	 * @param array $ids array with contact id(s)
	 * @param string $name ='' name to use for downloaded document
	 * @param string $dirs comma or whitespace separated directories, used if $document is a relative path
	 * @param array $header File name, mime & filesize if you want to send a header
	 *
	 * @return string with error-message on error
	 * @throws Api\Exception
	 */
	public function merge_file($document, $ids, &$name = '', $dirs = '', &$header = null)
	{
		//error_log(__METHOD__."('$document', ".array2string($ids).", '$name', dirs='$dirs') ->".function_backtrace());
		if(($error = $this->check_document($document, $dirs)))
		{
			return $error;
		}
		$content_url = Api\Vfs::PREFIX . $document;
		switch(($mimetype = Api\Vfs::mime_content_type($document)))
		{
			case 'message/rfc822':
				//error_log(__METHOD__."('$document', ".array2string($ids).", '$name', dirs='$dirs')=>$content_url ->".function_backtrace());
				$mail_bo = Api\Mail::getInstance();
				$mail_bo->openConnection();
				try
				{
					$_folder = $this->keep_emails ? '' : FALSE;
					$msgs = $mail_bo->importMessageToMergeAndSend($this, $content_url, $ids, $_folder, $import_id);
				}
				catch (Api\Exception\WrongUserinput $e)
				{
					// if this returns with an exeption, something failed big time
					return $e->getMessage();
				}
				//error_log(__METHOD__.__LINE__.' Message after importMessageToMergeAndSend:'.array2string($msgs));
				$retString = '';
				if(count($msgs['success']) > 0)
				{
					$retString .= count($msgs['success']) . ' ' . (count($msgs['success']) + count($msgs['failed']) == 1 ? lang('Message prepared for sending.') : lang('Message(s) send ok.'));
				}//implode('<br />',$msgs['success']);
				//if (strlen($retString)>0) $retString .= '<br />';
				foreach($msgs['failed'] as $c => $e)
				{
					$errorString .= lang('contact') . ' ' . lang('id') . ':' . $c . '->' . $e . '.';
				}
				if(count($msgs['failed']) > 0)
				{
					$retString .= count($msgs['failed']) . ' ' . lang('Message(s) send failed!') . '=>' . $errorString;
				}
				return $retString;
			case 'application/vnd.oasis.opendocument.text':
			case 'application/vnd.oasis.opendocument.spreadsheet':
			case 'application/vnd.oasis.opendocument.presentation':
			case 'application/vnd.oasis.opendocument.text-template':
			case 'application/vnd.oasis.opendocument.spreadsheet-template':
			case 'application/vnd.oasis.opendocument.presentation-template':
				switch($mimetype)
				{
					case 'application/vnd.oasis.opendocument.text':
						$ext = '.odt';
						break;
					case 'application/vnd.oasis.opendocument.spreadsheet':
						$ext = '.ods';
						break;
					case 'application/vnd.oasis.opendocument.presentation':
						$ext = '.odp';
						break;
					case 'application/vnd.oasis.opendocument.text-template':
						$ext = '.ott';
						break;
					case 'application/vnd.oasis.opendocument.spreadsheet-template':
						$ext = '.ots';
						break;
					case 'application/vnd.oasis.opendocument.presentation-template':
						$ext = '.otp';
						break;
				}
				$archive = tempnam($GLOBALS['egw_info']['server']['temp_dir'], basename($document, $ext) . '-') . $ext;
				copy($content_url, $archive);
				$content_url = 'zip://' . $archive . '#' . ($content_file = 'content.xml');
				$styles_url = 'zip://'.$archive.'#'.($styles_file = 'styles.xml');
				break;
			case 'application/vnd.openxmlformats-officedocument.wordprocessingml.d':    // mimetypes in vfs are limited to 64 chars
				$mimetype = 'application/vnd.openxmlformats-officedocument.wordprocessingml.document';
			case 'application/vnd.openxmlformats-officedocument.wordprocessingml.document':
			case 'application/vnd.ms-word.document.macroenabled.12':
				$archive = tempnam($GLOBALS['egw_info']['server']['temp_dir'], basename($document, '.docx') . '-') . '.docx';
				copy($content_url, $archive);
				$content_url = 'zip://' . $archive . '#' . ($content_file = 'word/document.xml');
				$fix = array(        // regular expression to fix garbled placeholders
									 '/' . preg_quote('$$</w:t></w:r><w:proofErr w:type="spellStart"/><w:r><w:t>', '/') . '([a-z0-9_]+)' .
									 preg_quote('</w:t></w:r><w:proofErr w:type="spellEnd"/><w:r><w:t>', '/') . '/i' => '$$\\1$$',
									 '/' . preg_quote('$$</w:t></w:r><w:proofErr w:type="spellStart"/><w:r><w:rPr><w:lang w:val="', '/') .
									 '([a-z]{2}-[A-Z]{2})' . preg_quote('"/></w:rPr><w:t>', '/') . '([a-z0-9_]+)' .
									 preg_quote('</w:t></w:r><w:proofErr w:type="spellEnd"/><w:r><w:rPr><w:lang w:val="', '/') .
									 '([a-z]{2}-[A-Z]{2})' . preg_quote('"/></w:rPr><w:t>$$', '/') . '/i'            => '$$\\2$$',
									 '/' . preg_quote('$</w:t></w:r><w:proofErr w:type="spellStart"/><w:r><w:t>', '/') . '([a-z0-9_]+)' .
									 preg_quote('</w:t></w:r><w:proofErr w:type="spellEnd"/><w:r><w:t>', '/') . '/i' => '$\\1$',
									 '/' . preg_quote('$ $</w:t></w:r><w:proofErr w:type="spellStart"/><w:r><w:t>', '/') . '([a-z0-9_]+)' .
									 preg_quote('</w:t></w:r><w:proofErr w:type="spellEnd"/><w:r><w:t>', '/') . '/i' => '$ $\\1$ $',
				);
				break;
			case 'application/xml':
				$fix = array(    // hack to get Excel 2003 to display additional rows in tables
								 '/ss:ExpandedRowCount="\d+"/' => 'ss:ExpandedRowCount="9999"',
				);
				break;
			case 'application/vnd.openxmlformats-officedocument.spreadsheetml.shee':
				$mimetype = 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet';
			case 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet':
			case 'application/vnd.ms-excel.sheet.macroenabled.12':
				$fix = array(    // hack to get Excel 2007 to display additional rows in tables
								 '/ss:ExpandedRowCount="\d+"/' => 'ss:ExpandedRowCount="9999"',
				);
				$archive = tempnam($GLOBALS['egw_info']['server']['temp_dir'], basename($document, '.xlsx') . '-') . '.xlsx';
				copy($content_url, $archive);
				$content_url = 'zip://' . $archive . '#' . ($content_file = 'xl/sharedStrings.xml');
				break;
		}
		$err = null;
		if(!($merged =& $this->merge($content_url, $ids, $err, $mimetype, $fix)))
		{
			//error_log(__METHOD__."() !this->merge() err=$err");
			return $err;
		}
		if (isset($styles_file) && !($merged_styles =& $this->merge($styles_url,$ids,$err,$mimetype,$fix)))
		{
			//error_log(__METHOD__."() !this->merge() err=$err");
			return $err;
		}
		// Apply HTML formatting to target document, if possible
		// check if we can use the XSL extension, to not give a fatal error and rendering whole merge-print non-functional
		if(class_exists('XSLTProcessor') && class_exists('DOMDocument') && $this->parse_html_styles)
		{
			try
			{
				$this->apply_styles($merged, $mimetype);
				if (isset($styles_file)) $this->apply_styles($merged_styles, $mimetype);
			}
			catch (\Exception $e)
			{
				// Error converting HTML styles over
				error_log($e->getMessage());
				error_log("Target document: $content_url, IDs: " . array2string($ids));

				// Try again, but strip HTML so user gets something
				$this->parse_html_styles = false;
				if(!($merged =& $this->merge($content_url, $ids, $err, $mimetype, $fix)))
				{
					return $err;
				}
				if (isset($styles_file) && !($merged_styles =& $this->merge($styles_url,$ids,$err,$mimetype,$fix)))
				{
					//error_log(__METHOD__."() !this->merge() err=$err");
					return $err;
				}
			}
			if($this->report_memory_usage)
			{
				error_log(__METHOD__ . "() after HTML processing " . Api\Vfs::hsize(memory_get_peak_usage(true)));
			}
		}
		if(!empty($name))
		{
			if(empty($ext))
			{
				$ext = '.' . pathinfo($document, PATHINFO_EXTENSION);
			}
			$name .= $ext;
		}
		else
		{
			$name = basename($document);
		}
		$header = array('name' => $name, 'mime' => $mimetype);
		if(isset($archive))
		{
			$zip = new ZipArchive;
			if($zip->open($archive, ZipArchive::CHECKCONS) !== true)
			{
				error_log(__METHOD__ . __LINE__ . " !ZipArchive::open('$archive',ZIPARCHIVE" . "::CHECKCONS) failed. Trying open without validating");
				if($zip->open($archive) !== true)
				{
					throw new Api\Exception("!ZipArchive::open('$archive',|ZIPARCHIVE::CHECKCONS)");
				}
			}
			if($zip->addFromString($content_file, $merged) !== true)
			{
				throw new Api\Exception("!ZipArchive::addFromString('$content_file',\$merged)");
			}
			if(isset($styles_file) && $zip->addFromString($styles_file, $merged_styles) !== true)
			{
				throw new Api\Exception("!ZipArchive::addFromString('$styles_file',\$merged_styles)");
			}
			if($zip->close() !== true)
			{
				throw new Api\Exception("!ZipArchive::close()");
			}
			unset($zip);
			unset($merged);
			if($this->report_memory_usage)
			{
				error_log(__METHOD__ . "() after ZIP processing " . Api\Vfs::hsize(memory_get_peak_usage(true)));
			}
			$header['filesize'] = filesize($archive);
		}
		else
		{
			$archive = tempnam($GLOBALS['egw_info']['server']['temp_dir'], basename($document, '.' . $ext) . '-') . '.' . $ext;
			if($mimetype == 'application/xml')
			{
				if(strpos($merged, '<?mso-application progid="Word.Document"?>') !== false)
				{
					$header['mimetype'] = 'application/msword';    // to open it automatically in word or oowriter
				}
				elseif(strpos($merged, '<?mso-application progid="Excel.Sheet"?>') !== false)
				{
					$header['mimetype'] = 'application/vnd.ms-excel';    // to open it automatically in excel or oocalc
				}
			}
			$handle = fopen($archive, 'w');
			fwrite($handle, $merged);
			fclose($handle);
		}
		return $archive;
	}

	/**
	 * Download document merged with contact(s)
	 * frontend for HTTP POST requests
	 * accepts POST vars and calls internal function download()
	 *   string data_document_name: the document name
	 *   string data_document_dir: the document vfs directory
	 *   string data_checked: contact id(s) to merge with (can be comma separated)
	 *
	 * @return string with error-message on error, otherwise it does NOT return
	 */
	public function download_by_request()
	{
		if(empty($_POST['data_document_name']))
		{
			return false;
		}
		if(empty($_POST['data_document_dir']))
		{
			return false;
		}
		if(empty($_POST['data_checked']))
		{
			return false;
		}

		return $this->download(
			$_POST['data_document_name'],
			explode(',', $_POST['data_checked']),
			'',
			$_POST['data_document_dir']
		);
	}

	/**
	 * Get a list of document actions / files from the given directory
	 *
	 * @param string $dirs Directory(s comma or space separated) to search
	 * @param string $prefix ='document_' prefix for array keys
	 * @param array|string $mime_filter =null allowed mime type(s), default all, negative filter if $mime_filter[0] === '!'
	 * @return array List of documents, suitable for a selectbox.  The key is document_<filename>.
	 */
	public static function get_documents($dirs, $prefix = 'document_', $mime_filter = null, $app = '')
	{
		$export_limit = self::getExportLimit($app);
		if(!$dirs || (!self::hasExportLimit($export_limit, 'ISALLOWED') && !self::is_export_limit_excepted()))
		{
			return array();
		}

		// split multiple comma or whitespace separated directories
		// to still allow space or comma in dirnames, we also use the trailing slash of all pathes to split
		if(count($dirs = preg_split('/[,\s]+\//', $dirs)) > 1)
		{
			foreach($dirs as $n => &$d)
			{
				if($n)
				{
					$d = '/' . $d;
				}    // re-adding trailing slash removed by split
			}
		}
		if($mime_filter && ($negativ_filter = $mime_filter[0] === '!'))
		{
			if(is_array($mime_filter))
			{
				unset($mime_filter[0]);
			}
			else
			{
				$mime_filter = substr($mime_filter, 1);
			}
		}
		$list = array();
		foreach($dirs as $dir)
		{
			if(($files = Api\Vfs::find($dir, array('need_mime' => true), true)))
			{
				foreach($files as $file)
				{
					// return only the mime-types we support
					$parts = explode('.', $file['name']);
					if(!self::is_implemented($file['mime'], '.' . array_pop($parts)))
					{
						continue;
					}
					if($mime_filter && $negativ_filter === in_array($file['mime'], (array)$mime_filter))
					{
						continue;
					}
					$list[$prefix . $file['name']] = Api\Vfs::decodePath($file['name']);
				}
			}
		}
		return $list;
	}

	/**
	 * From this number of documents, show them in submenus by mime type
	 */
	const SHOW_DOCS_BY_MIME_LIMIT = 10;

	/**
	 * Get insert-in-document action with optional default document on top
	 *
	 * If more than SHOW_DOCS_BY_MIME_LIMIT=10 documents found, they are displayed in submenus by mime type.
	 *
	 * @param string $dirs Directory(s comma or space separated) to search
	 * @param int $group see nextmatch_widget::egw_actions
	 * @param string $caption ='Insert in document'
	 * @param string $prefix ='document_'
	 * @param string $default_doc ='' full path to default document to show on top with action == 'document'!
	 * @param int|string $export_limit =null export-limit, default $GLOBALS['egw_info']['server']['export_limit']
	 * @return array see nextmatch_widget::egw_actions
	 */
	public static function document_action($dirs, $group = 0, $caption = 'Insert in document', $prefix = 'document_', $default_doc = '',
										   $export_limit = null)
	{
		if(count($dirs = preg_split('/[,\s]+\//', $dirs)) > 1)
		{
			foreach($dirs as $n => &$d)
			{
				if($n)
				{
					$d = '/' . $d;
				}    // re-adding trailing slash removed by split
			}
		}
		if($export_limit == null)
		{
			$export_limit = self::getExportLimit();
		}
		return array(
			'icon'           => 'file-earmark-arrow-down',
			'caption'        => $caption,
			'onExecute'  => 'javaScript:app.' . $GLOBALS['egw_info']['flags']['currentapp'] . '.mergeAction',
			// disable action if no document or export completly forbidden for non-admins
			'enabled'    => (self::hasExportLimit($export_limit, 'ISALLOWED') || self::is_export_limit_excepted()),
			'hideOnDisabled' => true,
			// do not show 'Insert in document', if no documents defined or no export allowed
			'group'          => $group,
			'merge_data' => array(
				'menuaction' => $GLOBALS['egw_info']['flags']['currentapp'] . '.' . get_called_class() . '.merge_entries',
				'merge'     => get_called_class(),
				'directory' => $dirs[0] ?? ""
			)
		);
	}

	/**
	 * Check if given document (relative path from document_actions()) exists in one of the given dirs
	 *
	 * @param string &$document maybe relative path of document, on return true absolute path to existing document
	 * @param string $dirs comma or whitespace separated directories
	 * @return string|boolean false if document exists, otherwise string with error-message
	 */
	public static function check_document(&$document, $dirs)
	{
		if($document[0] !== '/')
		{
			// split multiple comma or whitespace separated directories
			// to still allow space or comma in dirnames, we also use the trailing slash of all pathes to split
			if($dirs && ($dirs = preg_split('/[,\s]+\//', $dirs)))
			{
				foreach($dirs as $n => $dir)
				{
					if($n)
					{
						$dir = '/' . $dir;
					}    // re-adding trailing slash removed by split
					if(Api\Vfs::stat($dir . '/' . $document) && Api\Vfs::is_readable($dir . '/' . $document))
					{
						$document = $dir . '/' . $document;
						return false;
					}
				}
			}
		}
		elseif(Api\Vfs::stat($document) && Api\Vfs::is_readable($document))
		{
			return false;
		}
		//error_log(__METHOD__."('$document', dirs='$dirs') returning 'Document '$document' does not exist or is not readable for you!'");
		return lang("Document '%1' does not exist or is not readable for you!", $document);
	}

	/**
	 * Merge the selected IDs into the given document, save it to the VFS, then
	 * either open it in the editor or have the browser download the file.
	 *
	 * @param string[]|null $ids Allows extending classes to process IDs in their own way.  Leave null to pull from request.
	 * @param Merge|null $document_merge Already instantiated Merge object to do the merge.
	 * @param Array options
	 * @param boolean options[individual] Instead of merging all entries into the file, merge each entry into its own file
	 * @param boolean options[pdf] Convert result to PDF
	 * @param boolean options[link] Link generated file to the entry
	 * @param boolean $return Return the path of the generated document instead of opening or downloading
	 * @throws Api\Exception
	 * @throws Api\Exception\AssertionFailed
	 */
	public static function merge_entries(array $ids = null, Merge &$document_merge = null, $options = [], bool $return = null)
	{
		// Setup & get what we need
		if(is_null($document_merge) && class_exists($_REQUEST['merge']) && is_subclass_of($_REQUEST['merge'], 'EGroupware\\Api\\Storage\\Merge'))
		{
			$document_merge = new $_REQUEST['merge']();
		}
		elseif(is_null($document_merge))
		{
			$document_merge = new Api\Contacts\Merge();
		}

		$documents = (array)$_REQUEST['document'];

		// Check for an email
		$email = null;
		foreach($documents as $key => $d)
		{
			if(Vfs::mime_content_type($d) == 'message/rfc822')
			{
				$email = $d;
				unset($documents[$key]);
			}
		}
		if($email)
		{
			$mail_bo = Api\Mail::getInstance();
			$mail_bo->openConnection();
		}

		if(is_null(($ids)))
		{
			$ids = is_string($_REQUEST['id']) && strpos($_REQUEST['id'], '[') === FALSE ? explode(',', $_REQUEST['id']) : json_decode($_REQUEST['id'], true);
		}
		if($_REQUEST['select_all'] === 'true')
		{
			$ids = static::get_all_ids($document_merge);
		}
		foreach(['pdf', 'individual', 'link', 'download', 'open_email'] as $option)
		{
			$$option = is_null($options) || empty($options) ? (boolean)$_REQUEST['options'][$option] : (boolean)$options[$option];
		}
		$app = (is_null($options) ? $_REQUEST['options']['app'] : $options['app']) ?? $GLOBALS['egw_info']['flags']['currentapp'];

		if(is_null($return))
		{
			$return = (boolean)$_REQUEST['return'];
		}

		$id_group = $individual ? $ids : [$ids];
		$merged = $attach = [];
		$target = '';
		foreach($id_group as $ids)
		{
			foreach($documents as $document)
			{
				if($document != $email)
				{
					// Generate file
					$target = $document_merge->merge_entries_into_document((array)$ids, $document);
				}

				// PDF conversion
				if($pdf)
				{
					$converted = $document_merge->pdf_conversion($target);
					$target = $converted;
				}

				// Move to entry
				if($link)
				{
					foreach((array)$ids as $id)
					{
						// Copy to entry
						Api\Link::link($app, $id, Api\Link::VFS_APPNAME, Vfs::PREFIX . $target);
						// Remove
						Vfs::unlink($target);
						$target = Api\Link::vfs_path($app, $id, Vfs::basename(Vfs::PREFIX . $target));
					}
				}

				$merged[] = $target;
				$attach[] = Vfs::PREFIX . $target;
			}
			// One email per id group
			if($email && $mail_bo)
			{
				// Trick merge into not trying to open in compose
				$mail_ids = $ids;
				if(is_string($mail_ids))
				{
					$mail_ids = [$mail_ids];
				}
				if(count((array)$mail_ids) == 1 && !$open_email)
				{
					$mail_ids[] = null;
				}
				try
				{
					// Special email handling so we can grab it and stick it where we want
					$mail_folder = $document_merge->keep_emails ? (count($id_group) == 1 ? $mail_bo->getDraftFolder() : '') : FALSE;
					$mail_id = '';
					$msgs = $mail_bo->importMessageToMergeAndSend($document_merge, Api\Vfs::PREFIX . $email, $mail_ids, $mail_folder, $mail_id, $attach);
				}
				catch (\Exception $e)
				{
					$msg = "Unable to send email\n" . $e->getMessage();
					if($e->details)
					{
						$msg .= "\n" . $e->details;
					}
					throw new Api\Exception($msg, 100, $e);
				}
				// Save to VFS so we can link to entry
				if($link || $download)
				{
					// Load message
					$message = $mail_bo->getMessageRawBody($mail_id, '', $mail_folder);
					if(!$message)
					{
						throw new Api\Exception\AssertionFailed("Unable to read merged email\n" . $mail_folder . "/$mail_id");
					}

					$filename = $document_merge->get_filename($email, (array)$ids);
					if(!str_ends_with($filename, pathinfo($email, PATHINFO_EXTENSION)))
					{
						$filename .= '.' . pathinfo($email, PATHINFO_EXTENSION);
					}
					if($download)
					{
						$target = $document_merge->get_save_path($filename);

						// Make sure we won't overwrite something already there
						$target = Vfs::make_unique($target);
						file_put_contents(Vfs::PREFIX . $target, $message);
						$merged[] = $target;
					}
					if($link)
					{
						foreach((array)$ids as $id)
						{
							$target = Api\Link::vfs_path($app, $id, $filename);

							// Make sure we won't overwrite something already there
							$target = Vfs::make_unique($target);

							file_put_contents(Vfs::PREFIX . $target, $message);
							if(!$download)
							{
								$merged[] = $target;
							}
						}
					}
				}
				$attach = [];
			}
		}

		// Find out what to do with it - can't handle multiple documents directly
		if($return || count($merged) > 1)
		{
			return $merged;
		}
		// Open email in compose?
		if($email && count($id_group) == 1 && $mail_id && class_exists("mail_ui"))
		{
			$mail_uid = \mail_ui::generateRowID($mail_bo->profileID, $mail_folder, $mail_id);
			$mail_popup = '';
			$mail_info = Api\Link::edit('mail', $mail_uid, $mail_popup);
			$mail_info['from'] = 'composefromdraft';
			Api\Framework::popup(Api\Framework::link("/index.php", $mail_info), '_blank', $mail_popup);
			return;
		}
		// Merge done, present to user
		if($document_merge->get_editable_mimes()[Vfs::mime_content_type($target)] &&
			!in_array(Vfs::mime_content_type($target), explode(',', $GLOBALS['egw_info']['user']['preferences']['filemanager']['collab_excluded_mimes'])))
		{
			\Egroupware\Api\Egw::redirect_link('/index.php', array(
				'menuaction' => 'collabora.EGroupware\\Collabora\\Ui.editor',
				'path'       => $target
			));
		}
		else
		{
			\Egroupware\Api\Egw::redirect_link(Vfs::download_url($target, true));
		}
	}

	/**
	 * Merge the given IDs into the given document, saves to VFS, and returns the path
	 *
	 * @param array $ids
	 * @param $document
	 * @return string|void
	 * @throws Api\Exception\AssertionFailed
	 * @throws Api\Exception\NotFound
	 * @throws Api\Exception\WrongParameter
	 * @throws Vfs\Exception\ProtectedDirectory
	 */
	protected function merge_entries_into_document(array $ids, $document)
	{
		if(($error = $this->check_document($document, '')))
		{
			error_log(__METHOD__ . "({$_REQUEST['document']}) $error");
			return;
		}

		$filename = $this->get_filename($document, $ids);
		$result = $this->merge_file($document, $ids, $filename, '', $header);

		if(!is_file($result) || !is_readable($result))
		{
			throw new Api\Exception\AssertionFailed("Unable to generate merge file\n" . $result);
		}
		// Put it into the vfs using user's preferred directory if writable,
		// or expected home dir (/home/username) if not
		$target = $this->get_save_path($filename);

		// Make sure we won't overwrite something already there
		$target = Vfs::make_unique($target);

		copy($result, Vfs::PREFIX . $target);
		unlink($result);

		return $target;
	}

	/**
	 * Convert a file into PDF
	 *
	 * Removes the original file
	 *
	 * @param $path
	 * @return mixed|string Path to converted file
	 * @throws Api\Exception\AssertionFailed
	 * @throws Api\Exception\NotFound
	 * @throws Api\Exception\WrongParameter
	 * @throws Vfs\Exception\ProtectedDirectory
	 */
	protected function pdf_conversion($path)
	{
		$editable_mimes = $this->get_editable_mimes();
		if($editable_mimes[Vfs::mime_content_type($path)])
		{
			$error = '';
			$converted_path = '';
			$convert = new Conversion();
			$convert->convert($path, $converted_path, 'pdf', $error);

			if($error)
			{
				error_log(__METHOD__ . "({$_REQUEST['document']}) $path => $converted_path Error in PDF conversion: $error");
			}
			else
			{
				// Remove original
				Vfs::unlink($path);
				$path = $converted_path;
			}
		}
		return $path;
	}

	/**
	 * Get a list of editable mime types
	 *
	 * @return array|String[]
	 */
	protected function get_editable_mimes()
	{
		$editable_mimes = array();
		try
		{
			if(class_exists('EGroupware\\collabora\\Bo') &&
				$GLOBALS['egw_info']['user']['apps']['collabora'] &&
				($discovery = \EGroupware\collabora\Bo::discover()) &&
				$GLOBALS['egw_info']['user']['preferences']['filemanager']['merge_open_handler'] != 'download'
			)
			{
				$editable_mimes = $discovery;
			}
		}
		catch (\Exception $e)
		{
			// ignore failed discovery
			unset($e);
		}
		return $editable_mimes;
	}


	/**
	 * Merge one or more entries into one or more documents.
	 *
	 * @param array|null $ids
	 * @param \EGroupware\Api\Contacts\Merge|null $document_merge
	 * @param $documents
	 * @param $options
	 * @return string[] location(s) of merged files
	 */
	public static function ajax_merge_multiple(array $ids = [], $documents = [], $options = [])
	{
		$response = Api\Json\Response::get();
		$_REQUEST['document'] = $documents;
		$app = $options['app'] ?? $GLOBALS['egw_info']['flags']['currentapp'];
		$message = implode(', ', Api\Link::titles($app, $ids)) . ":\n";
		$return = true;
		$open_email = $options['open_email'];

		try
		{
			$merge_result = static::merge_entries($ids, $document_merge, $options, !$open_email);
		}
		catch (\Exception $e)
		{
			$response->error($message . $e->getMessage());
		}

		foreach($merge_result as $result)
		{
			if(is_string($result))
			{
				if($options['download'])
				{
					$response->apply('egw.open_link', [Vfs::download_url($result, true), '_browser']);
				}
				$message .= $result . "\n";
			}
			else
			{
				if($result['failed'])
				{
					$response->error($message . implode(", ", $result['failed']));
				}
				else
				{
					if($result['success'])
					{
						$message .= implode(", ", $result['success']);
					}
				}
			}
		}
		$response->data($message);
	}

	/**
	 * Generate a filename for the merged file, without extension
	 *
	 * Default filename is just the name of the template.
	 * We use the placeholders from get_filename_placeholders() and the application's document filename preference
	 * to generate a custom filename.
	 *
	 * @param string $document Template filename
	 * @param string[] $ids List of IDs being merged
	 * @return string
	 */
	protected function get_filename($document, $ids = []) : string
	{
		$name = '';
		if(isset($GLOBALS['egw_info']['user']['preferences'][$this->get_app()][static::PREF_DOCUMENT_FILENAME]))
		{
			$pref = $GLOBALS['egw_info']['user']['preferences'][$this->get_app()][static::PREF_DOCUMENT_FILENAME];
			$placeholders = $this->get_filename_placeholders($document, $ids);

			// Make values safe for VFS
			foreach($placeholders as &$value)
			{
				$value = Api\Mail::clean_subject_for_filename($value);
			}

			// Do replacement
			$name = str_replace(
				array_keys($placeholders),
				array_values($placeholders),
				is_array($pref) ? implode(' ', $pref) : str_replace(',', ', ', $pref)
			);
		}
		return $name;
	}

	protected function get_filename_placeholders($document, $ids)
	{
		$ext = '.' . pathinfo($document, PATHINFO_EXTENSION);
		$link_title = count($ids) == 1 ? Api\Link::title($this->get_app(), $ids[0]) : lang("multiple");
		$contact_title = count($ids) == 1 ? Api\Link::title($this->get_app(), $ids[0]) : lang("multiple");
		$current_date = str_replace('/', '-', Api\DateTime::to('now', Api\DateTime::$user_dateformat));


		$values = [
			'$$document$$'      => basename($document, $ext),
			'$$link_title$$'    => $link_title,
			'$$contact_title$$' => $contact_title,
			'$$current_date$$'  => $current_date
		];

		return $values;
	}

	/**
	 * Return a path where we can save the generated file
	 * Takes into account user preference.
	 *
	 * @param string $filename The name of the generated file, including extension
	 * @return string
	 */
	protected function get_save_path($filename) : string
	{
		// Default is home directory
		$target = (Vfs::is_writable(Vfs::get_home_dir()) ?
			Vfs::get_home_dir() :
			"/home/{$GLOBALS['egw_info']['user']['account_lid']}"
		);

		// Check for a configured preferred directory
		if(!empty($pref = $GLOBALS['egw_info']['user']['preferences'][$this->get_app()][Merge::PREF_STORE_LOCATION] ?? false) && Vfs::is_writable($pref))
		{
			$target = $pref;
		}

		return $target . "/$filename";
	}

	/**
	 * Get all ids for when they try to do 'Select All', then merge into document
	 *
	 * @param Api\Contacts\Merge $merge App-specific merge object
	 */
	protected static function get_all_ids(Api\Storage\Merge $merge)
	{
		$ids = array();
		$locations = array('index', 'session_data');

		// Get app
		list($appname, $_merge) = explode('_', get_class($merge));

		if($merge instanceof Api\Contacts\Merge)
		{
			$appname = 'addressbook';
		}
		switch(get_class($merge))
		{
			case \calendar_merge::class:
				$ui_class = 'calendar_uilist';
				$locations = array('calendar_list');
				break;
			case \projectmanager_merge::class;
				$ui_class = 'projectmanager_ui';
				$locations = array('project_list');
				break;
			default:
				$ui_class = $appname . '_ui';
				break;
		}
		return static::get_all_ids_app($appname, $merge, $ui_class, $locations);
	}

	protected static function get_all_ids_app($appname, &$merge, $ui_class, $locations)
	{
		// Ask app
		if(class_exists($ui_class))
		{
			$ui = new $ui_class();
			if(method_exists($ui_class, 'get_all_ids'))
			{
				return $ui->get_all_ids();
			}

			// Try cache, preferring get_rrows over get_rows
			if(method_exists($ui_class, $get_rows = 'get_rrows') || method_exists($ui_class, $get_rows = 'get_rows'))
			{
				foreach($locations as $location)
				{
					$session = Api\Cache::getSession($appname, $location);
					if($session && $session['row_id'])
					{
						break;
					}
				}
				$rows = $readonlys = array();
				@set_time_limit(0);            // switch off the execution time limit, as it's for big selections to small
				$session['num_rows'] = -1;     // all
				$ui->$get_rows($session, $rows, $readonlys);
				foreach($rows as $row_number => $row)
				{
					if(!is_numeric($row_number))
					{
						continue;
					}
					$row_id = $row[$session['row_id'] ? $session['row_id'] : 'id'];
					switch(get_class($merge))
					{
						case \calendar_merge::class:
							$explody = explode(':', $row_id);
							$ids[] = array('id' => $explody[0], 'recur_date' => $explody[1]);
							break;
						case \timesheet_merge::class:
							// Skip the rows with totalss
							if(!is_numeric($row_id))
							{
								continue 2;
							}    // +1 for switch
						// Fall through
						default:
							$ids[] = $row_id;
					}
				}
			}
		}
		return $ids;
	}

	/**
	 * Get a list of supported extentions
	 */
	public static function get_file_extensions()
	{
		return array('txt', 'rtf', 'odt', 'ods', 'docx', 'xml', 'eml');
	}

	/**
	 * Format a number according to user prefs with decimal and thousands separator
	 *
	 * Reimplemented from etemplate to NOT use user prefs for Excel 2003, which gives an xml error
	 *
	 * @param int|float|string $number
	 * @param int $num_decimal_places =2
	 * @param string $_mimetype =''
	 * @return string
	 */
	static public function number_format($number, $num_decimal_places = 2, $_mimetype = '')
	{
		if(is_null($number) || (string)$number === '')
		{
			return '';
		}
		//error_log(__METHOD__.$_mimetype);
		switch($_mimetype)
		{
			case 'application/xml':    // Excel 2003
			case 'application/vnd.oasis.opendocument.spreadsheet': // OO.o spreadsheet
				return number_format(str_replace(' ', '', $number), $num_decimal_places, '.', '');
		}
		return Api\Etemplate::number_format($number, $num_decimal_places);
	}

	/**
	 * Get a list of common replacements available to all applications
	 *
	 * @return array
	 */
	public function get_common_replacements()
	{
		$share_replacements = !$GLOBALS['egw_info']['user']['apps']['stylite'] ? [] : [
			'share'                     => lang("Share this %1 via URL", lang('entry')),
			// We don't allow anonymous file access through entries - the links tab will be empty
			//	'share-files'               => lang("Share this %1 via URL", lang('entry')) . " " . lang("include access to any linked files (links tab)"),
			'share-files_only'          => lang('Share just the associated filemanager directory, not the %1', lang('entry')),
			'share/writable'            => lang("Share this %1 via URL", lang('entry')) . '. ' . lang('Allow anonymous editing'),
			//	'share-files/writable'      => lang("Share this %1 via URL", lang('entry')) . " " . lang("include access to any linked files (links tab)"),
			'share-files_only/writable' => lang('Share just the associated filemanager directory, not the %1', lang('entry')) . '. ' . lang('Allow anonymous editing'),
		];

		return $share_replacements +
			array(
				// Link to current entry
				'link'                          => lang('URL of current record'),
				'link/href'                     => lang('HTML link to the current record'),
				'link/title'                    => lang('Link title of current record'),

				// Link system - linked entries
				'links'                         => lang('Titles of any entries linked to the current record, excluding attached files'),
				'links/href'                    => lang('HTML links to any entries linked to the current record, excluding attached files'),
				'links/url'                     => lang('URLs of any entries linked to the current record, excluding attached files'),
				'attachments'                   => lang('List of files linked to the current record'),
				'links_attachments'             => lang('Links and attached files'),
				'links/[appname]'               => lang('Links to specified application.  Example: {{links/infolog}}'),
				'links/[appname]/[fieldname]' => lang('Field from the first link to the specified application.  Example: {{links/addressbook/n_fn}}'),

				// General information
				'date'                          => lang('Date'),
				'datetime'                      => lang('Date + time'),
				'time'                          => lang('Time'),
				'user/n_fn'                     => lang('Name of current user, all other contact fields are valid too'),
				'user/account_lid'              => lang('Username'),

				// Merge control
				'pagerepeat'                    => lang('For serial letter use this tag. Put the content, you want to repeat between two Tags.'),
				'label'                         => lang('Use this tag for addresslabels. Put the content, you want to repeat, between two tags.'),
				'labelplacement'                => lang('Tag to mark positions for address labels'),

				// Commands
				'IF fieldname'                  => lang('Example {{IF n_prefix~Mr~Hello Mr.~Hello Ms.}} - search the field "n_prefix", for "Mr", if found, write Hello Mr., else write Hello Ms.'),
				'IF fieldname~EMPTY~True~False' => lang('Check for empty values in IF statements.  Example {{IF url~EMPTY~~Website:}} - If url is not empty, writes "Website:"'),
				'NELF'                          => lang('Example {{NELF role}} - if field role is not empty, you will get a new line with the value of field role'),
				'NENVLF'                        => lang('Example {{NENVLF role}} - if field role is not empty, set a LF without any value of the field'),
				'LETTERPREFIX'                  => lang('Example {{LETTERPREFIX}} - Gives a letter prefix without double spaces, if the title is emty for  example'),
				'LETTERPREFIXCUSTOM'            => lang('Example {{LETTERPREFIXCUSTOM n_prefix title n_family}} - Example: Mr Dr. James Miller'),
			);
	}

	/**
	 * Get a list of common placeholders
	 *
	 * @param string $prefix
	 */
	public function get_common_placeholder_list($prefix = '')
	{
		$placeholders = [
			'URLs'             => [],
			'Egroupware links' => [],
			'Sharing'          => [],
			'General'          => [],
			'Repeat'           => [],
			'Commands'         => []
		];
		// Iterate through the list & switch groups as we go
		// Hopefully a little better than assigning each field to a group
		$group = 'URLs';
		foreach($this->get_common_replacements() as $name => $label)
		{
			if(in_array($name, array('user/n_fn', 'user/account_lid')))
			{
				continue;
			}    // don't show them, they're in 'User'

			switch($name)
			{
				case 'share':
					$group = 'Sharing';
					break;
				case 'link':
					$group = "URLs";
					break;
				case 'links':
					$group = 'Egroupware links';
					break;
				case 'date':
					$group = 'General';
					break;
				case 'pagerepeat':
					$group = 'Repeat';
					break;
				case 'IF fieldname':
					$group = 'Commands';
			}
			$marker = $this->prefix($prefix, $name, '{');
			if(!array_filter($placeholders, function ($a) use ($marker)
			{
				return array_key_exists($marker, $a);
			}))
			{
				$placeholders[$group][] = [
					'value' => $marker,
					'label' => $label
				];
			}
		}
		return $placeholders;
	}

	/**
	 * Get a list of placeholders for the current user
	 */
	public function get_user_placeholder_list($prefix = '')
	{
		$contacts = new Api\Contacts\Merge();
		$replacements = $contacts->get_placeholder_list($this->prefix($prefix, 'user'));
		unset($replacements['details'][$this->prefix($prefix, 'user/account_id', '{')]);
		$replacements['account'] = [
			[
				'value' => $this->prefix($prefix, 'user/account_id', '{'),
				'label' => 'Account ID'
			],
			[
				'value' => $this->prefix($prefix, 'user/account_lid', '{'),
				'label' => 'Login ID'
			]
		];

		return $replacements;
	}

	/**
	 * Get the list of placeholders for an application's customfields
	 * If the customfield is a link to another application, we expand and add those placeholders as well
	 */
	protected function add_customfield_placeholders(&$placeholders, $prefix = '')
	{
		foreach(Customfields::get($this->get_app()) as $name => $field)
		{
			// Avoid recursing between custom fields of different apps
			if(array_key_exists($field['type'], Api\Link::app_list()) && substr_count($prefix, '#') == 0)
			{
				$app = self::get_app_class($field['type']);
				if($app)
				{
					$this->add_linked_placeholders($placeholders, $name, $app->get_placeholder_list(($prefix ? $prefix . '/' : '') . '#' . $name));
				}
			}
			else
			{
				$placeholders['custom fields'][] = [
					'value' => $this->prefix($prefix, '#' . $name, '{'),
					'label' => $field['label'] . ($field['type'] == 'select-account' ? '*' : '')
				];
			}
		}
	}

	/**
	 * Get a list of placeholders provided.
	 *
	 * Placeholders are grouped logically.  Group key should have a user-friendly translation.
	 * Override this method and specify the placeholders, as well as groups or a specific order
	 */
	public function get_placeholder_list($prefix = '')
	{
		$placeholders = [
		];

		$this->add_customfield_placeholders($placeholders, $prefix);

		return $placeholders;
	}

	/**
	 * Add placeholders from another application into the given list of placeholders
	 *
	 * This is used for linked entries (like info_contact) and custom fields where the type is another application.
	 * Here we adjust the group name, and add the group to the end of the placeholder list
	 * @param array $placeholder_list Our placeholder list
	 * @param string $base_name Name of the entry (eg: Contact, custom field name)
	 * @param array $add_placeholder_groups Placeholder list from the other app.  Placeholders should include any needed prefix
	 */
	protected function add_linked_placeholders(&$placeholder_list, $base_name, $add_placeholder_groups) : void
	{
		if(!$add_placeholder_groups)
		{
			// Skip empties
			return;
		}
		/*
				foreach($add_placeholder_groups as $group => $add_placeholders)
				{
					$placeholder_list[$base_name . ': ' . lang($group)] = $add_placeholders;
				}
		*/
		$placeholder_list[$base_name] = $add_placeholder_groups;
	}

	/**
	 * Get preference settings
	 *
	 * Merge has some preferences that the same across apps, but can have different values for each app:
	 * - Default document
	 * - Document template directory
	 * - Filename customization
	 * - Generated document target directory
	 */
	public function merge_preferences()
	{
		$settings = array();

		switch($this->get_app())
		{
			case 'addressbook':
				// lang() will mangle the %5C encoded \ in api.EGroupware\\Api\\Contacts\\Merge.show_replacements
				$pref_list_link = Api\Html::a_href('', Api\Framework::link('/index.php', [
					'menuaction' => 'addressbook.addressbook_merge.show_replacements'
				],                                                         $this->get_app())
				);
				break;
			default:
				$pref_list_link = Api\Html::a_href('', Api\Framework::link('/index.php', [
					'menuaction' => $this->get_app() . '.' . get_class($this) . '.show_replacements'
				],                                                         $this->get_app())
				);
		}
		$pref_list_link = str_replace('</a>', '', $pref_list_link);
		$settings[self::PREF_DEFAULT_TEMPLATE] = array(
			'type'     => 'vfs_file',
			'size'     => 60,
			'label'    => 'Default document to insert entries',
			'name'     => self::PREF_DEFAULT_TEMPLATE,
			'help'     => lang('If you specify a document (full vfs path) here, %1 displays an extra document icon for each entry. That icon allows to download the specified document with the data inserted.', lang($this->get_app())) . ' ' .
				lang('the document can contain placeholder like {{%3}}, to be replaced with the data (%1full list of placeholder names%2).', $pref_list_link, '</a>', 'name') . ' <br/>' .
				lang('The following document-types are supported:') . implode(',', self::get_file_extensions()),
			'run_lang' => false,
			'xmlrpc'   => True,
			'admin'    => False,
		);
		$settings[self::PREF_TEMPLATE_DIR] = array(
			'type'     => 'vfs_dirs',
			'size'     => 60,
			'label'    => 'Directory with documents to insert entries',
			'name'     => self::PREF_TEMPLATE_DIR,
			'help'     => lang('if you specify a directory (full vfs path) here, %1 displays an action for each document. that action allows to download the specified document with the data inserted.', lang($this->get_app())) . ' ' .
				lang('the document can contain placeholder like {{%3}}, to be replaced with the data (%1full list of placeholder names%2).', $pref_list_link, '</a>', 'name') . ' <br/>' .
				lang('The following document-types are supported:') . implode(',', self::get_file_extensions()),
			'run_lang' => false,
			'xmlrpc'   => True,
			'admin'    => False,
			'default'  => '/templates/' . $this->get_app(),
		);
		$settings[self::PREF_STORE_LOCATION] = array(
			'type'  => 'vfs_dir',
			'size'  => 60,
			'label' => 'Directory for storing merged documents',
			'name'  => self::PREF_STORE_LOCATION,
			'help'  => lang('When you merge entries into documents, they will be stored here.  If no directory is provided, they will be stored in your home directory (%1)', Vfs::get_home_dir())
		);

		$settings[self::PREF_DOCUMENT_FILENAME] = array(
			'type'    => 'taglist',
			'label'   => 'Merged document filename',
			'name'    => self::PREF_DOCUMENT_FILENAME,
			'values' => static::DOCUMENT_FILENAME_OPTIONS,
			'help'    => 'Choose the default filename for merged documents.',
			'xmlrpc'  => True,
			'admin'   => False,
			'default' => '$$document$$',
		);

		return $settings;
	}

	/**
	 * Show replacement placeholders for the app
	 *
	 * Generates a page that shows all the available placeholders for this appliction.  By default,
	 * we have all placeholders generated in get_placeholder_list() (including any custom fields)
	 * as well as the common and current user placeholders.
	 *
	 * By overridding show_replacements_hook(), extending classes can override without having to
	 * re-implement everything.
	 */
	public function show_replacements()
	{
		$template_name = 'api.show_replacements';
		$content = $sel_options = $readonlys = $preserve = array();

		$content['appname'] = $this->get_app();
		$content['placeholders'] = $this->remap_replacement_list($this->get_placeholder_list());
		$content['extra'] = array();
		$content['common'] = $this->remap_replacement_list($this->get_common_placeholder_list());
		$content['user'] = $this->remap_replacement_list($this->get_user_placeholder_list());

		$this->show_replacements_hook($template_name, $content, $sel_options, $readonlys);
		$etemplate = new Api\Etemplate($template_name);

		$etemplate->exec('filemanager.filemanager_ui.file', $content, $sel_options, $readonlys, $preserve, 2);
	}

	/**
	 * Helper function for show_replacements() to change the output of get_placeholder_list() into somethig
	 * more suited for etemplate repeating rows.
	 *
	 * @param $list
	 * @return array
	 */
	protected function remap_replacement_list($list, $title_prefix = '')
	{
		$new_list = [];
		foreach($list as $group_title => $group_placeholders)
		{
			if(is_array($group_placeholders) && !array_key_exists('0', $group_placeholders))
			{
				// Limit how far we go through linked entries
				if($title_prefix)
				{
					continue;
				}
				$new_list = array_merge($new_list, $this->remap_replacement_list($group_placeholders, $group_title));
			}
			else
			{
				$new_list[] = [
					'title'        => ($title_prefix ? lang($title_prefix) . ': ' : '') . lang($group_title),
					'placeholders' => $group_placeholders
				];
			}
		}
		return $new_list;
	}

	/**
	 * Hook for extending apps to customise the replacements UI without having to override the whole method.
	 *
	 * This can include detailed descriptions or instructions, documentation of tables and custom stuff
	 * Set $content['extra_template'] to a template ID with extra descriptions or instructions and it will be
	 * added into the main template.
	 *
	 * @param string $template_name
	 * @param $content
	 * @param $sel_options
	 * @param $readonlys
	 */
	protected function show_replacements_hook(&$template_name, &$content, &$sel_options, &$readonlys)
	{
	}

	/**
	 * Allow to attach files to merged mails
	 *
	 * Called from mail.mail_compose.compose
	 *
	 * @param int|string $id
	 * @return array[] array of array with values for keys
	 * - "data": path or open file resource,
	 * - "name": filename to be used for attachment
	 * - "type": mime-type of attachment
	 */
	public function getAttachments($id)
	{
		return [];
	}
}