<?php
/**
 * API: loading for web-components modified eTemplate from server
 *
 * Usage: /egroupware/api/etemplate.php/<app>/templates/default/<name>.xet
 *
 * @link https://www.egroupware.org
 * @author Ralf Becker <rb@egroupware-org>
 * @package api
 * @license http://opensource.org/licenses/gpl-license.php GPL - GNU General Public License
 */

use EGroupware\Api;

// add et2- prefix to following widgets/tags
const ADD_ET2_PREFIX_REGEXP = '#<((/?)([vh]?box|textbox|textarea|button|colorpicker|description))(/?|\s[^>]*)>#m';

// switch evtl. set output-compression off, as we cant calculate a Content-Length header with transparent compression
ini_set('zlib.output_compression', 0);

$GLOBALS['egw_info'] = array(
	'flags' => array(
		'currentapp'                  => 'api',
		'noheader'                    => true,
		// miss-use session creation callback to send the template, in case we have no session
		'autocreate_session_callback' => 'send_template',
		'nocachecontrol'              => true,
	)
);

$start = microtime(true);
include '../header.inc.php';

send_template();

function send_template()
{
	$header_include = microtime(true);

	// release session, as we don't need it and it blocks parallel requests
	$GLOBALS['egw']->session->commit_session();

	header('Content-Type: application/xml; charset=UTF-8');

	//$path = EGW_SERVER_ROOT.$_SERVER['PATH_INFO'];
	// check for customized template in VFS
	list(, $app, , $template, $name) = explode('/', $_SERVER['PATH_INFO']);
	$path = Api\Etemplate::rel2path(Api\Etemplate::relPath($app . '.' . basename($name, '.xet'), $template));
	if(empty($path) || !file_exists($path) || !is_readable($path))
	{
		http_response_code(404);
		exit;
	}
	/* disable caching for now, as you need to delete the cache, once you change ADD_ET2_PREFIX_REGEXP
	$cache = $GLOBALS['egw_info']['server']['temp_dir'].'/egw_cache/eT2-Cache-'.$GLOBALS['egw_info']['server']['install_id'].$_SERVER['PATH_INFO'];
	if (file_exists($cache) && filemtime($cache) > filemtime($path) &&
		($str = file_get_contents($cache)) !== false)
	{
		$cache_read = microtime(true);
	}
	else*/
	if(($str = file_get_contents($path)) !== false &&
		// eTemplate marked as legacy, return unchanged template without web-components / et2-prefix
		!preg_match('/<overlay[^>]* legacy="true"/', $str))
	{
		// fix <menulist...><menupopup type="select-*"/></menulist> --> <select type="select-*" .../>
		$str = preg_replace('#<menulist([^>]*)>[\r\n\s]*<menupopup([^>]+>)[\r\n\s]*</menulist>#', '<select$1$2', $str);

		// fix legacy options, so new client-side has not to deal with them
		$str = preg_replace_callback('#<([^- ]+)(-[^ ]+)?[^>]* (options="([^"]+)")[ />]#', static function($matches)
		{
			// take care of (static) type attribute, if used
			if (preg_match('/ type="([a-z-]+)"/', $matches[0], $type))
			{
				str_replace('<'.$matches[1].$matches[2], '<'.$type[1], $matches[0]);
				str_replace($type[0], '', $matches[0]);
				list($matches[1], $matches[2]) = explode('-', $type[1], 2);
			}
			static $legacy_options = array( // use "ignore" to ignore further comma-sep. values, otherwise they are all in last attribute
				'select'       => 'empty_label,ignore',
				'box'          => ',cellpadding,cellspacing,keep',
				'hbox'         => 'cellpadding,cellspacing,keep',
				'vbox'         => 'cellpadding,cellspacing,keep',
				'groupbox'     => 'cellpadding,cellspacing,keep',
				'checkbox'     => 'selected_value,unselected_value,ro_true,ro_false',
				'radio'        => 'set_value,ro_true,ro_false',
				'customfields' => 'sub-type,use-private,field-names',
				'date'         => 'data_format,ignore', // Legacy option "mode" was never implemented in et2
				'description'  => 'bold-italic,link,activate_links,label_for,link_target,link_popup_size,link_title',
			);
			// prefer more specific type-subtype over just type
			$names = $legacy_options[$matches[1].$matches[2]] ?? $legacy_options[$matches[1]] ?? null;
			if (isset($names))
			{
				$names = explode(',', $names);
				$values = Api\Etemplate\Widget::csv_split($matches[4], count($names));
				if (count($values) < count($names))
				{
					$values = array_merge($values, array_fill(count($values), count($names)-count($values), ''));
				}
				$attrs = array_diff(array_combine($names, $values), ['', null]);
				unset($attrs['ignore']);
				// fix select options can be either multiple or empty_label
				if ($matches[1] === 'select' && !empty($attrs['empty_label']) && (int)$attrs['empty_label'] > 0)
				{
					$attrs['multiple'] = (int)$attrs['empty_label'];
					unset($matches['empty_label']);
				}
				$options = '';
				foreach($attrs as $attr => $value)
				{
					$options .= $attr.'="'.$value.'" ';
				}
				return str_replace($matches[3], $options, $matches[0]);
			}
			return $matches[0];
		}, $str);

		// fix <textbox multiline="true" .../> --> <textarea .../> (et2-prefix and self-closing is handled below)
		$str = preg_replace('#<textbox(.*?)\smultiline="true"(.*?)/>#u', '<textarea$1$2/>', $str);

		// fix <buttononly.../> --> <button type="buttononly".../>
		$str = preg_replace('#<buttononly\s(.*?)/>#u', '<button type="buttononly" $1/>', $str);

		$str = preg_replace_callback(ADD_ET2_PREFIX_REGEXP, static function (array $matches)
		{
			return '<' . $matches[2] . 'et2-' . $matches[3] .
				// web-components must not be self-closing (no "<et2-button .../>", but "<et2-button ...></et2-button>")
				(substr($matches[4], -1) === '/' ? substr($matches[4], 0, -1) . '></et2-' . $matches[3] : $matches[4]) . '>';
		}, $str);

		// handling of partially implemented select and date widget (only readonly or simple select without tags or search attribute or options)
		$str = preg_replace_callback('#<(select|date)(-[^ ]+)? ([^>]+)/>#', static function (array $matches)
		{
			preg_match_all('/(^| )([a-z0-9_-]+)="([^"]+)"/', $matches[3], $attrs, PREG_PATTERN_ORDER);
			$attrs = array_combine($attrs[2], $attrs[3]);

			// add et2-prefix for <select-* or <date-* readonly="true"
			if (isset($attrs['readonly']) && !in_array($attrs['readonly'], ['false', '0']) ||
				// also add it for <date* and <select* without search or tags attribute
				$matches[1] === 'date' || $matches[1] === 'select' && !isset($attrs['search']) && !isset($attrs['tags']))
			{
				// type attribute need to go in widget type <select type="select-account" --> <et2-select-account
				if (empty($matches[2]) && isset($attrs['type']))
				{
					$matches[1] = $attrs['type'];
					$matches[3] = str_replace('type="'.$attrs['type'].'"', '', $matches[3]);
				}
				return '<et2-'.$matches[1].$matches[2].' '.$matches[3].'></et2-'.$matches[1].$matches[2].'>';
			}
			return $matches[0];
		}, $str);

		$processing = microtime(true);

		if(isset($cache) && (file_exists($cache_dir = dirname($cache)) || mkdir($cache_dir, 0755, true)))
		{
			file_put_contents($cache, $str);
		}
	}
	// stop here for not existing file path-traversal for both file and cache here
	if(empty($str) || strpos($path, '..') !== false)
	{
		http_response_code(404);
		exit;
	}

	// headers to allow caching, egw_framework specifies etag on url to force reload, even with Expires header
	Api\Session::cache_control(86400);    // cache for one day
	$etag = '"' . md5($str) . '"';
	Header('ETag: ' . $etag);

	// if servers send a If-None-Match header, response with 304 Not Modified, if etag matches
	if(isset($_SERVER['HTTP_IF_NONE_MATCH']) && $_SERVER['HTTP_IF_NONE_MATCH'] === $etag)
	{
		header("HTTP/1.1 304 Not Modified");
		exit;
	}

	// we run our own gzip compression, to set a correct Content-Length of the encoded content
	if(function_exists('gzencode') && in_array('gzip', explode(',', $_SERVER['HTTP_ACCEPT_ENCODING']), true))
	{
		$gzip_start = microtime(true);
		$str = gzencode($str);
		header('Content-Encoding: gzip');
		$gziping = microtime(true) - $gzip_start;
	}
	header('X-Timing: header-include=' . number_format($header_include - $GLOBALS['start'], 3) .
		   (empty($processing) ? ', cache-read=' . number_format($cache_read - $header_include, 3) :
			   ', processing=' . number_format($processing - $header_include, 3)) .
		   (!empty($gziping) ? ', gziping=' . number_format($gziping, 3) : '') .
		   ', total=' . number_format(microtime(true) - $GLOBALS['start'], 3)
	);

	// Content-Length header is important, otherwise browsers dont cache!
	Header('Content-Length: ' . bytes($str));
	echo $str;

	exit;    // stop further processing eg. redirect to login
}