summaryrefslogtreecommitdiff
path: root/program/include/rcube_template.php
blob: b4f6e9be518b10248f0bdf4094a6b8965b73d8d4 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
<?php

/*
 +-----------------------------------------------------------------------+
 | program/include/rcube_template.php                                    |
 |                                                                       |
 | This file is part of the Roundcube Webmail client                     |
 | Copyright (C) 2006-2011, The Roundcube Dev Team                       |
 | Licensed under the GNU GPL                                            |
 |                                                                       |
 | PURPOSE:                                                              |
 |   Class to handle HTML page output using a skin template.             |
 |   Extends rcube_html_page class from rcube_shared.inc                 |
 |                                                                       |
 +-----------------------------------------------------------------------+
 | Author: Thomas Bruederli <roundcube@gmail.com>                        |
 +-----------------------------------------------------------------------+

 $Id$

 */


/**
 * Class to create HTML page output using a skin template
 *
 * @package View
 * @todo Documentation
 * @uses rcube_html_page
 */
class rcube_template extends rcube_html_page
{
    private $app;
    private $config;
    private $pagetitle = '';
    private $message = null;
    private $js_env = array();
    private $js_labels = array();
    private $js_commands = array();
    private $object_handlers = array();
    private $plugin_skin_path;
    private $template_name;

    public $browser;
    public $framed = false;
    public $env = array();
    public $type = 'html';
    public $ajax_call = false;

    // deprecated names of templates used before 0.5
    private $deprecated_templates = array(
        'contact' => 'showcontact',
        'contactadd' => 'addcontact',
        'contactedit' => 'editcontact',
        'identityedit' => 'editidentity',
        'messageprint' => 'printmessage',
    );

    /**
     * Constructor
     *
     * @todo   Replace $this->config with the real rcube_config object
     */
    public function __construct($task, $framed = false)
    {
        parent::__construct();

        $this->app = rcmail::get_instance();
        $this->config = $this->app->config->all();
        $this->browser = new rcube_browser();

        //$this->framed = $framed;
        $this->set_env('task', $task);
        $this->set_env('x_frame_options', $this->app->config->get('x_frame_options', 'sameorigin'));

        // load the correct skin (in case user-defined)
        $this->set_skin($this->config['skin']);

        // add common javascripts
        $this->add_script('var '.JS_OBJECT_NAME.' = new rcube_webmail();', 'head_top');

        // don't wait for page onload. Call init at the bottom of the page (delayed)
        $this->add_script(JS_OBJECT_NAME.'.init();', 'docready');

        $this->scripts_path = 'program/js/';
        $this->include_script('jquery.min.js');
        $this->include_script('common.js');
        $this->include_script('app.js');

        // register common UI objects
        $this->add_handlers(array(
            'loginform'       => array($this, 'login_form'),
            'preloader'       => array($this, 'preloader'),
            'username'        => array($this, 'current_username'),
            'message'         => array($this, 'message_container'),
            'charsetselector' => array($this, 'charset_selector'),
        ));
    }

    /**
     * Set environment variable
     *
     * @param string Property name
     * @param mixed Property value
     * @param boolean True if this property should be added to client environment
     */
    public function set_env($name, $value, $addtojs = true)
    {
        $this->env[$name] = $value;
        if ($addtojs || isset($this->js_env[$name])) {
            $this->js_env[$name] = $value;
        }
    }

    /**
     * Set page title variable
     */
    public function set_pagetitle($title)
    {
        $this->pagetitle = $title;
    }

    /**
     * Getter for the current page title
     *
     * @return string The page title
     */
    public function get_pagetitle()
    {
        if (!empty($this->pagetitle)) {
            $title = $this->pagetitle;
        }
        else if ($this->env['task'] == 'login') {
            $title = rcube_label(array('name' => 'welcome', 'vars' => array('product' => $this->config['product_name'])));
        }
        else {
            $title = ucfirst($this->env['task']);
        }

        return $title;
    }

    /**
     * Set skin
     */
    public function set_skin($skin)
    {
        $valid = false;

        if (!empty($skin) && is_dir('skins/'.$skin) && is_readable('skins/'.$skin)) {
            $skin_path = 'skins/'.$skin;
            $valid = true;
        }
        else {
            $skin_path = $this->config['skin_path'] ? $this->config['skin_path'] : 'skins/default';
            $valid = !$skin;
        }

        $this->app->config->set('skin_path', $skin_path);
        $this->config['skin_path'] = $skin_path;

        return $valid;
    }

    /**
     * Check if a specific template exists
     *
     * @param string Template name
     * @return boolean True if template exists
     */
    public function template_exists($name)
    {
        $filename = $this->config['skin_path'] . '/templates/' . $name . '.html';
        return (is_file($filename) && is_readable($filename)) || ($this->deprecated_templates[$name] && $this->template_exists($this->deprecated_templates[$name]));
    }

    /**
     * Register a template object handler
     *
     * @param  string Object name
     * @param  string Function name to call
     * @return void
     */
    public function add_handler($obj, $func)
    {
        $this->object_handlers[$obj] = $func;
    }

    /**
     * Register a list of template object handlers
     *
     * @param  array Hash array with object=>handler pairs
     * @return void
     */
    public function add_handlers($arr)
    {
        $this->object_handlers = array_merge($this->object_handlers, $arr);
    }

    /**
     * Register a GUI object to the client script
     *
     * @param  string Object name
     * @param  string Object ID
     * @return void
     */
    public function add_gui_object($obj, $id)
    {
        $this->add_script(JS_OBJECT_NAME.".gui_object('$obj', '$id');");
    }

    /**
     * Call a client method
     *
     * @param string Method to call
     * @param ... Additional arguments
     */
    public function command()
    {
        $cmd = func_get_args();
        if (strpos($cmd[0], 'plugin.') !== false)
          $this->js_commands[] = array('triggerEvent', $cmd[0], $cmd[1]);
        else
          $this->js_commands[] = $cmd;
    }

    /**
     * Add a localized label to the client environment
     */
    public function add_label()
    {
        $args = func_get_args();
        if (count($args) == 1 && is_array($args[0]))
          $args = $args[0];

        foreach ($args as $name) {
            $this->js_labels[$name] = rcube_label($name);
        }
    }

    /**
     * Invoke display_message command
     *
     * @param string  $message  Message to display
     * @param string  $type     Message type [notice|confirm|error]
     * @param array   $vars     Key-value pairs to be replaced in localized text
     * @param boolean $override Override last set message
     * @param int     $timeout  Message display time in seconds
     * @uses self::command()
     */
    public function show_message($message, $type='notice', $vars=null, $override=true, $timeout=0)
    {
        if ($override || !$this->message) {
            if (rcube_label_exists($message)) {
                if (!empty($vars))
                    $vars = array_map('Q', $vars);
                $msgtext = rcube_label(array('name' => $message, 'vars' => $vars));
            }
            else
                $msgtext = $message;

            $this->message = $message;
            $this->command('display_message', $msgtext, $type, $timeout * 1000);
        }
    }

    /**
     * Delete all stored env variables and commands
     *
     * @return void
     * @uses   rcube_html::reset()
     * @uses   self::$env
     * @uses   self::$js_env
     * @uses   self::$js_commands
     * @uses   self::$object_handlers
     */
    public function reset()
    {
        $this->env = array();
        $this->js_env = array();
        $this->js_labels = array();
        $this->js_commands = array();
        $this->object_handlers = array();
        parent::reset();
    }

    /**
     * Redirect to a certain url
     *
     * @param mixed Either a string with the action or url parameters as key-value pairs
     * @see rcmail::url()
     */
    public function redirect($p = array())
    {
        $location = $this->app->url($p);
        header('Location: ' . $location);
        exit;
    }

    /**
     * Send the request output to the client.
     * This will either parse a skin tempalte or send an AJAX response
     *
     * @param string  Template name
     * @param boolean True if script should terminate (default)
     */
    public function send($templ = null, $exit = true)
    {
        if ($templ != 'iframe') {
            // prevent from endless loops
            if ($exit != 'recur' && $this->app->plugins->is_processing('render_page')) {
                raise_error(array('code' => 505, 'type' => 'php',
                  'file' => __FILE__, 'line' => __LINE__,
                  'message' => 'Recursion alert: ignoring output->send()'), true, false);
                return;
            }
            $this->parse($templ, false);
        }
        else {
            $this->framed = $templ == 'iframe' ? true : $this->framed;
            $this->write();
        }

        // set output asap
        ob_flush();
        flush();

        if ($exit) {
            exit;
        }
    }

    /**
     * Process template and write to stdOut
     *
     * @param string HTML template
     * @see rcube_html_page::write()
     * @override
     */
    public function write($template = '')
    {
        // unlock interface after iframe load
        $unlock = preg_replace('/[^a-z0-9]/i', '', $_REQUEST['_unlock']);
        if ($this->framed) {
            array_unshift($this->js_commands, array('set_busy', false, null, $unlock));
        }
        else if ($unlock) {
            array_unshift($this->js_commands, array('hide_message', $unlock));
        }

        if (!empty($this->script_files))
          $this->set_env('request_token', $this->app->get_request_token());

        // write all env variables to client
        $js = $this->framed ? "if(window.parent) {\n" : '';
        $js .= $this->get_js_commands() . ($this->framed ? ' }' : '');
        $this->add_script($js, 'head_top');

        // send clickjacking protection headers
        $iframe = $this->framed || !empty($_REQUEST['_framed']);
        if (!headers_sent() && ($xframe = $this->app->config->get('x_frame_options', 'sameorigin')))
            header('X-Frame-Options: ' . ($iframe && $xframe == 'deny' ? 'sameorigin' : $xframe));

        // call super method
        parent::write($template, $this->config['skin_path']);
    }

    /**
     * Parse a specific skin template and deliver to stdout (or return)
     *
     * @param  string  Template name
     * @param  boolean Exit script
     * @param  boolean Don't write to stdout, return parsed content instead
     *
     * @link   http://php.net/manual/en/function.exit.php
     */
    function parse($name = 'main', $exit = true, $write = true)
    {
        $skin_path = $this->config['skin_path'];
        $plugin    = false;
        $realname  = $name;
        $temp      = explode('.', $name, 2);

        $this->plugin_skin_path = null;
        $this->template_name    = $realname;

        if (count($temp) > 1) {
            $plugin    = $temp[0];
            $name      = $temp[1];
            $skin_dir  = $plugin . '/skins/' . $this->config['skin'];
            $skin_path = $this->plugin_skin_path = $this->app->plugins->dir . $skin_dir;

            // fallback to default skin
            if (!is_dir($skin_path)) {
                $skin_dir = $plugin . '/skins/default';
                $skin_path = $this->plugin_skin_path = $this->app->plugins->dir . $skin_dir;
            }
        }

        $path = "$skin_path/templates/$name.html";

        if (!is_readable($path) && $this->deprecated_templates[$realname]) {
            $path = "$skin_path/templates/".$this->deprecated_templates[$realname].".html";
            if (is_readable($path))
                raise_error(array('code' => 502, 'type' => 'php',
                    'file' => __FILE__, 'line' => __LINE__,
                    'message' => "Using deprecated template '".$this->deprecated_templates[$realname]
                        ."' in ".$this->config['skin_path']."/templates. Please rename to '".$realname."'"),
                true, false);
        }

        // read template file
        if (($templ = @file_get_contents($path)) === false) {
            raise_error(array(
                'code' => 501,
                'type' => 'php',
                'line' => __LINE__,
                'file' => __FILE__,
                'message' => 'Error loading template for '.$realname
                ), true, true);
            return false;
        }

        // replace all path references to plugins/... with the configured plugins dir
        // and /this/ to the current plugin skin directory
        if ($plugin) {
            $templ = preg_replace(array('/\bplugins\//', '/(["\']?)\/this\//'), array($this->app->plugins->url, '\\1'.$this->app->plugins->url.$skin_dir.'/'), $templ);
        }

        // parse for specialtags
        $output = $this->parse_conditions($templ);
        $output = $this->parse_xml($output);

        // trigger generic hook where plugins can put additional content to the page
        $hook = $this->app->plugins->exec_hook("render_page", array('template' => $realname, 'content' => $output));

        $output = $this->parse_with_globals($hook['content']);

        // make sure all <form> tags have a valid request token
        $output = preg_replace_callback('/<form\s+([^>]+)>/Ui', array($this, 'alter_form_tag'), $output);
        $this->footer = preg_replace_callback('/<form\s+([^>]+)>/Ui', array($this, 'alter_form_tag'), $this->footer);

        if ($write) {
            // add debug console
            if ($realname != 'error' && ($this->config['debug_level'] & 8)) {
                $this->add_footer('<div id="console" style="position:absolute;top:5px;left:5px;width:405px;padding:2px;background:white;z-index:9000;display:none">
                    <a href="#toggle" onclick="con=$(\'#dbgconsole\');con[con.is(\':visible\')?\'hide\':\'show\']();return false">console</a>
                    <textarea name="console" id="dbgconsole" rows="20" cols="40" wrap="off" style="display:none;width:400px;border:none;font-size:10px" spellcheck="false"></textarea></div>'
                );
                $this->add_script(
                    "if (!window.console || !window.console.log) {\n".
                    "  window.console = new rcube_console();\n".
                    "  $('#console').show();\n".
                    "}", 'foot');
            }
            $this->write(trim($output));
        }
        else {
            return $output;
        }

        if ($exit) {
            exit;
        }
    }

    /**
     * Return executable javascript code for all registered commands
     *
     * @return string $out
     */
    private function get_js_commands()
    {
        $out = '';
        if (!$this->framed && !empty($this->js_env)) {
            $out .= JS_OBJECT_NAME . '.set_env('.json_serialize($this->js_env).");\n";
        }
        if (!empty($this->js_labels)) {
            $this->command('add_label', $this->js_labels);
        }
        foreach ($this->js_commands as $i => $args) {
            $method = array_shift($args);
            foreach ($args as $i => $arg) {
                $args[$i] = json_serialize($arg);
            }
            $parent = $this->framed || preg_match('/^parent\./', $method);
            $out .= sprintf(
                "%s.%s(%s);\n",
                ($parent ? 'if(window.parent && parent.'.JS_OBJECT_NAME.') parent.' : '') . JS_OBJECT_NAME,
                preg_replace('/^parent\./', '', $method),
                implode(',', $args)
            );
        }

        return $out;
    }

    /**
     * Make URLs starting with a slash point to skin directory
     *
     * @param  string Input string
     * @return string
     */
    public function abs_url($str)
    {
        if ($str[0] == '/')
            return $this->config['skin_path'] . $str;
        else
            return $str;
    }


    /*****  Template parsing methods  *****/

    /**
     * Replace all strings ($varname)
     * with the content of the according global variable.
     */
    private function parse_with_globals($input)
    {
        $GLOBALS['__version'] = Q(RCMAIL_VERSION);
        $GLOBALS['__comm_path'] = Q($this->app->comm_path);
        return preg_replace_callback('/\$(__[a-z0-9_\-]+)/',
	    array($this, 'globals_callback'), $input);
    }

    /**
     * Callback funtion for preg_replace_callback() in parse_with_globals()
     */
    private function globals_callback($matches)
    {
        return $GLOBALS[$matches[1]];
    }

    /**
     * Public wrapper to dipp into template parsing.
     *
     * @param  string $input
     * @return string
     * @uses   rcube_template::parse_xml()
     * @since  0.1-rc1
     */
    public function just_parse($input)
    {
        return $this->parse_xml($input);
    }

    /**
     * Parse for conditional tags
     *
     * @param  string $input
     * @return string
     */
    private function parse_conditions($input)
    {
        $matches = preg_split('/<roundcube:(if|elseif|else|endif)\s+([^>]+)>\n?/is', $input, 2, PREG_SPLIT_DELIM_CAPTURE);
        if ($matches && count($matches) == 4) {
            if (preg_match('/^(else|endif)$/i', $matches[1])) {
                return $matches[0] . $this->parse_conditions($matches[3]);
            }
            $attrib = parse_attrib_string($matches[2]);
            if (isset($attrib['condition'])) {
                $condmet = $this->check_condition($attrib['condition']);
                $submatches = preg_split('/<roundcube:(elseif|else|endif)\s+([^>]+)>\n?/is', $matches[3], 2, PREG_SPLIT_DELIM_CAPTURE);
                if ($condmet) {
                    $result = $submatches[0];
                    $result.= ($submatches[1] != 'endif' ? preg_replace('/.*<roundcube:endif\s+[^>]+>\n?/Uis', '', $submatches[3], 1) : $submatches[3]);
                }
                else {
                    $result = "<roundcube:$submatches[1] $submatches[2]>" . $submatches[3];
                }
                return $matches[0] . $this->parse_conditions($result);
            }
            raise_error(array(
                'code' => 500,
                'type' => 'php',
                'line' => __LINE__,
                'file' => __FILE__,
                'message' => "Unable to parse conditional tag " . $matches[2]
            ), true, false);
        }
        return $input;
    }


    /**
     * Determines if a given condition is met
     *
     * @todo   Get rid off eval() once I understand what this does.
     * @todo   Extend this to allow real conditions, not just "set"
     * @param  string Condition statement
     * @return boolean True if condition is met, False if not
     */
    private function check_condition($condition)
    {
        return eval("return (".$this->parse_expression($condition).");");
    }


    /**
     * Inserts hidden field with CSRF-prevention-token into POST forms
     */
    private function alter_form_tag($matches)
    {
        $out = $matches[0];
        $attrib  = parse_attrib_string($matches[1]);

        if (strtolower($attrib['method']) == 'post') {
            $hidden = new html_hiddenfield(array('name' => '_token', 'value' => $this->app->get_request_token()));
            $out .= "\n" . $hidden->show();
        }

        return $out;
    }


    /**
     * Parses expression and replaces variables
     *
     * @param  string Expression statement
     * @return string Expression value
     */
    private function parse_expression($expression)
    {
        return preg_replace(
            array(
                '/session:([a-z0-9_]+)/i',
                '/config:([a-z0-9_]+)(:([a-z0-9_]+))?/i',
                '/env:([a-z0-9_]+)/i',
                '/request:([a-z0-9_]+)/i',
                '/cookie:([a-z0-9_]+)/i',
                '/browser:([a-z0-9_]+)/i',
                '/template:name/i',
            ),
            array(
                "\$_SESSION['\\1']",
                "\$this->app->config->get('\\1',get_boolean('\\3'))",
                "\$this->env['\\1']",
                "get_input_value('\\1', RCUBE_INPUT_GPC)",
                "\$_COOKIE['\\1']",
                "\$this->browser->{'\\1'}",
                $this->template_name,
            ),
            $expression);
    }


    /**
     * Search for special tags in input and replace them
     * with the appropriate content
     *
     * @param  string Input string to parse
     * @return string Altered input string
     * @todo   Use DOM-parser to traverse template HTML
     * @todo   Maybe a cache.
     */
    private function parse_xml($input)
    {
        return preg_replace_callback('/<roundcube:([-_a-z]+)\s+([^>]+)>/Ui', array($this, 'xml_command'), $input);
    }


    /**
     * Callback function for parsing an xml command tag
     * and turn it into real html content
     *
     * @param  array Matches array of preg_replace_callback
     * @return string Tag/Object content
     */
    private function xml_command($matches)
    {
        $command = strtolower($matches[1]);
        $attrib  = parse_attrib_string($matches[2]);

        // empty output if required condition is not met
        if (!empty($attrib['condition']) && !$this->check_condition($attrib['condition'])) {
            return '';
        }

        // execute command
        switch ($command) {
            // return a button
            case 'button':
                if ($attrib['name'] || $attrib['command']) {
                    return $this->button($attrib);
                }
                break;

            // show a label
            case 'label':
                if ($attrib['name'] || $attrib['command']) {
                    $vars = $attrib + array('product' => $this->config['product_name']);
                    unset($vars['name'], $vars['command']);
                    $label = rcube_label($attrib + array('vars' => $vars));
                    return !$attrib['noshow'] ? (get_boolean((string)$attrib['html']) ? $label : Q($label)) : '';
                }
                break;

            // include a file
            case 'include':
                if (!$this->plugin_skin_path || !is_file($path = realpath($this->plugin_skin_path . $attrib['file'])))
                    $path = realpath(($attrib['skin_path'] ? $attrib['skin_path'] : $this->config['skin_path']).$attrib['file']);
                
                if (is_readable($path)) {
                    if ($this->config['skin_include_php']) {
                        $incl = $this->include_php($path);
                    }
                    else {
                      $incl = file_get_contents($path);
                    }
                    $incl = $this->parse_conditions($incl);
                    return $this->parse_xml($incl);
                }
                break;

            case 'plugin.include':
                $hook = $this->app->plugins->exec_hook("template_plugin_include", $attrib);
                return $hook['content'];
                break;

            // define a container block
            case 'container':
                if ($attrib['name'] && $attrib['id']) {
                    $this->command('gui_container', $attrib['name'], $attrib['id']);
                    // let plugins insert some content here
                    $hook = $this->app->plugins->exec_hook("template_container", $attrib);
                    return $hook['content'];
                }
                break;

            // return code for a specific application object
            case 'object':
                $object = strtolower($attrib['name']);
                $content = '';

                // we are calling a class/method
                if (($handler = $this->object_handlers[$object]) && is_array($handler)) {
                    if ((is_object($handler[0]) && method_exists($handler[0], $handler[1])) ||
                    (is_string($handler[0]) && class_exists($handler[0])))
                    $content = call_user_func($handler, $attrib);
                }
                // execute object handler function
                else if (function_exists($handler)) {
                    $content = call_user_func($handler, $attrib);
                }
                else if ($object == 'logo') {
                    $attrib += array('alt' => $this->xml_command(array('', 'object', 'name="productname"')));
                    if ($this->config['skin_logo'])
                        $attrib['src'] = $this->config['skin_logo'];
                    $content = html::img($attrib);
                }
                else if ($object == 'productname') {
                    $name = !empty($this->config['product_name']) ? $this->config['product_name'] : 'Roundcube Webmail';
                    $content = Q($name);
                }
                else if ($object == 'version') {
                    $ver = (string)RCMAIL_VERSION;
                    if (is_file(INSTALL_PATH . '.svn/entries')) {
                        if (preg_match('/Revision:\s(\d+)/', @shell_exec('svn info'), $regs))
                          $ver .= ' [SVN r'.$regs[1].']';
                    }
                    $content = Q($ver);
                }
                else if ($object == 'steptitle') {
                  $content = Q($this->get_pagetitle());
                }
                else if ($object == 'pagetitle') {
                    if (!empty($this->config['devel_mode']) && !empty($_SESSION['username']))
                      $title = $_SESSION['username'].' :: ';
                    else if (!empty($this->config['product_name']))
                      $title = $this->config['product_name'].' :: ';
                    else
                      $title = '';
                    $title .= $this->get_pagetitle();
                    $content = Q($title);
                }

                // exec plugin hooks for this template object
                $hook = $this->app->plugins->exec_hook("template_object_$object", $attrib + array('content' => $content));
                return $hook['content'];

            // return code for a specified eval expression
            case 'exp':
                $value = $this->parse_expression($attrib['expression']);
                return eval("return Q($value);");

            // return variable
            case 'var':
                $var = explode(':', $attrib['name']);
                $name = $var[1];
                $value = '';

                switch ($var[0]) {
                    case 'env':
                        $value = $this->env[$name];
                        break;
                    case 'config':
                        $value = $this->config[$name];
                        if (is_array($value) && $value[$_SESSION['imap_host']]) {
                            $value = $value[$_SESSION['imap_host']];
                        }
                        break;
                    case 'request':
                        $value = get_input_value($name, RCUBE_INPUT_GPC);
                        break;
                    case 'session':
                        $value = $_SESSION[$name];
                        break;
                    case 'cookie':
                        $value = htmlspecialchars($_COOKIE[$name]);
                        break;
                    case 'browser':
                        $value = $this->browser->{$name};
                        break;
                }

                if (is_array($value)) {
                    $value = implode(', ', $value);
                }

                return Q($value);
                break;
        }
        return '';
    }

    /**
     * Include a specific file and return it's contents
     *
     * @param string File path
     * @return string Contents of the processed file
     */
    private function include_php($file)
    {
        ob_start();
        include $file;
        $out = ob_get_contents();
        ob_end_clean();

        return $out;
    }

    /**
     * Create and register a button
     *
     * @param  array Named button attributes
     * @return string HTML button
     * @todo   Remove all inline JS calls and use jQuery instead.
     * @todo   Remove all sprintf()'s - they are pretty, but also slow.
     */
    public function button($attrib)
    {
        static $s_button_count = 100;

        // these commands can be called directly via url
        $a_static_commands = array('compose', 'list', 'preferences', 'folders', 'identities');

        if (!($attrib['command'] || $attrib['name'])) {
            return '';
        }

        // try to find out the button type
        if ($attrib['type']) {
            $attrib['type'] = strtolower($attrib['type']);
        }
        else {
            $attrib['type'] = ($attrib['image'] || $attrib['imagepas'] || $attrib['imageact']) ? 'image' : 'link';
        }

        $command = $attrib['command'];

        if ($attrib['task'])
          $command = $attrib['task'] . '.' . $command;

        if (!$attrib['image']) {
            $attrib['image'] = $attrib['imagepas'] ? $attrib['imagepas'] : $attrib['imageact'];
        }

        if (!$attrib['id']) {
            $attrib['id'] =  sprintf('rcmbtn%d', $s_button_count++);
        }
        // get localized text for labels and titles
        if ($attrib['title']) {
            $attrib['title'] = Q(rcube_label($attrib['title'], $attrib['domain']));
        }
        if ($attrib['label']) {
            $attrib['label'] = Q(rcube_label($attrib['label'], $attrib['domain']));
        }
        if ($attrib['alt']) {
            $attrib['alt'] = Q(rcube_label($attrib['alt'], $attrib['domain']));
        }

        // set title to alt attribute for IE browsers
        if ($this->browser->ie && !$attrib['title'] && $attrib['alt']) {
            $attrib['title'] = $attrib['alt'];
        }

        // add empty alt attribute for XHTML compatibility
        if (!isset($attrib['alt'])) {
            $attrib['alt'] = '';
        }

        // register button in the system
        if ($attrib['command']) {
            $this->add_script(sprintf(
                "%s.register_button('%s', '%s', '%s', '%s', '%s', '%s');",
                JS_OBJECT_NAME,
                $command,
                $attrib['id'],
                $attrib['type'],
                $attrib['imageact'] ? $this->abs_url($attrib['imageact']) : $attrib['classact'],
                $attrib['imagesel'] ? $this->abs_url($attrib['imagesel']) : $attrib['classsel'],
                $attrib['imageover'] ? $this->abs_url($attrib['imageover']) : ''
            ));

            // make valid href to specific buttons
            if (in_array($attrib['command'], rcmail::$main_tasks)) {
                $attrib['href'] = rcmail_url(null, null, $attrib['command']);
                $attrib['onclick'] = sprintf("%s.command('switch-task','%s');return false", JS_OBJECT_NAME, $attrib['command']);
            }
            else if ($attrib['task'] && in_array($attrib['task'], rcmail::$main_tasks)) {
                $attrib['href'] = rcmail_url($attrib['command'], null, $attrib['task']);
            }
            else if (in_array($attrib['command'], $a_static_commands)) {
                $attrib['href'] = rcmail_url($attrib['command']);
            }
            else if ($attrib['command'] == 'permaurl' && !empty($this->env['permaurl'])) {
              $attrib['href'] = $this->env['permaurl'];
            }
        }

        // overwrite attributes
        if (!$attrib['href']) {
            $attrib['href'] = '#';
        }
        if ($attrib['task']) {
            if ($attrib['classact'])
                $attrib['class'] = $attrib['classact'];
        }
        else if ($command && !$attrib['onclick']) {
            $attrib['onclick'] = sprintf(
                "return %s.command('%s','%s',this)",
                JS_OBJECT_NAME,
                $command,
                $attrib['prop']
            );
        }

        $out = '';

        // generate image tag
        if ($attrib['type']=='image') {
            $attrib_str = html::attrib_string(
                $attrib,
                array(
                    'style', 'class', 'id', 'width', 'height', 'border', 'hspace',
                    'vspace', 'align', 'alt', 'tabindex', 'title'
                )
            );
            $btn_content = sprintf('<img src="%s"%s />', $this->abs_url($attrib['image']), $attrib_str);
            if ($attrib['label']) {
                $btn_content .= ' '.$attrib['label'];
            }
            $link_attrib = array('href', 'onclick', 'onmouseover', 'onmouseout', 'onmousedown', 'onmouseup', 'target');
        }
        else if ($attrib['type']=='link') {
            $btn_content = isset($attrib['content']) ? $attrib['content'] : ($attrib['label'] ? $attrib['label'] : $attrib['command']);
            $link_attrib = array('href', 'onclick', 'title', 'id', 'class', 'style', 'tabindex', 'target');
        }
        else if ($attrib['type']=='input') {
            $attrib['type'] = 'button';

            if ($attrib['label']) {
                $attrib['value'] = $attrib['label'];
            }

            $attrib_str = html::attrib_string(
                $attrib,
                array(
                    'type', 'value', 'onclick', 'id', 'class', 'style', 'tabindex'
                )
            );
            $out = sprintf('<input%s disabled="disabled" />', $attrib_str);
        }

        // generate html code for button
        if ($btn_content) {
            $attrib_str = html::attrib_string($attrib, $link_attrib);
            $out = sprintf('<a%s>%s</a>', $attrib_str, $btn_content);
        }

        return $out;
    }


    /*  ************* common functions delivering gui objects **************  */


    /**
     * Create a form tag with the necessary hidden fields
     *
     * @param array Named tag parameters
     * @return string HTML code for the form
     */
    public function form_tag($attrib, $content = null)
    {
      if ($this->framed || !empty($_REQUEST['_framed'])) {
        $hiddenfield = new html_hiddenfield(array('name' => '_framed', 'value' => '1'));
        $hidden = $hiddenfield->show();
      }

      if (!$content)
        $attrib['noclose'] = true;

      return html::tag('form',
        $attrib + array('action' => "./", 'method' => "get"),
        $hidden . $content,
        array('id','class','style','name','method','action','enctype','onsubmit'));
    }


    /**
     * Build a form tag with a unique request token
     *
     * @param array Named tag parameters including 'action' and 'task' values which will be put into hidden fields
     * @param string Form content
     * @return string HTML code for the form
     */
    public function request_form($attrib, $content = '')
    {
        $hidden = new html_hiddenfield();
        if ($attrib['task']) {
            $hidden->add(array('name' => '_task', 'value' => $attrib['task']));
        }
        if ($attrib['action']) {
            $hidden->add(array('name' => '_action', 'value' => $attrib['action']));
        }

        unset($attrib['task'], $attrib['request']);
        $attrib['action'] = './';

        // we already have a <form> tag
        if ($attrib['form']) {
            if ($this->framed || !empty($_REQUEST['_framed']))
                $hidden->add(array('name' => '_framed', 'value' => '1'));
            return $hidden->show() . $content;
        }
        else
            return $this->form_tag($attrib, $hidden->show() . $content);
    }


    /**
     * GUI object 'username'
     * Showing IMAP username of the current session
     *
     * @param array Named tag parameters (currently not used)
     * @return string HTML code for the gui object
     */
    public function current_username($attrib)
    {
        static $username;

        // alread fetched
        if (!empty($username)) {
            return $username;
        }

        // Current username is an e-mail address
        if (strpos($_SESSION['username'], '@')) {
            $username = $_SESSION['username'];
        }
        // get e-mail address from default identity
        else if ($sql_arr = $this->app->user->get_identity()) {
            $username = $sql_arr['email'];
        }
        else {
            $username = $this->app->user->get_username();
        }

        return rcube_idn_to_utf8($username);
    }


    /**
     * GUI object 'loginform'
     * Returns code for the webmail login form
     *
     * @param array Named parameters
     * @return string HTML code for the gui object
     */
    private function login_form($attrib)
    {
        $default_host = $this->config['default_host'];
        $autocomplete = (int) $this->config['login_autocomplete'];

        $_SESSION['temp'] = true;

        // save original url
        $url = get_input_value('_url', RCUBE_INPUT_POST);
        if (empty($url) && !preg_match('/_(task|action)=logout/', $_SERVER['QUERY_STRING']))
            $url = $_SERVER['QUERY_STRING'];

        // set atocomplete attribute
        $user_attrib = $autocomplete > 0 ? array() : array('autocomplete' => 'off');
        $host_attrib = $autocomplete > 0 ? array() : array('autocomplete' => 'off');
        $pass_attrib = $autocomplete > 1 ? array() : array('autocomplete' => 'off');

        $input_task   = new html_hiddenfield(array('name' => '_task', 'value' => 'login'));
        $input_action = new html_hiddenfield(array('name' => '_action', 'value' => 'login'));
        $input_tzone  = new html_hiddenfield(array('name' => '_timezone', 'id' => 'rcmlogintz', 'value' => '_default_'));
        $input_dst    = new html_hiddenfield(array('name' => '_dstactive', 'id' => 'rcmlogindst', 'value' => '_default_'));
        $input_url    = new html_hiddenfield(array('name' => '_url', 'id' => 'rcmloginurl', 'value' => $url));
        $input_user   = new html_inputfield(array('name' => '_user', 'id' => 'rcmloginuser')
            + $attrib + $user_attrib);
        $input_pass   = new html_passwordfield(array('name' => '_pass', 'id' => 'rcmloginpwd')
            + $attrib + $pass_attrib);
        $input_host   = null;

        if (is_array($default_host) && count($default_host) > 1) {
            $input_host = new html_select(array('name' => '_host', 'id' => 'rcmloginhost'));

            foreach ($default_host as $key => $value) {
                if (!is_array($value)) {
                    $input_host->add($value, (is_numeric($key) ? $value : $key));
                }
                else {
                    $input_host = null;
                    break;
                }
            }
        }
        else if (is_array($default_host) && ($host = array_pop($default_host))) {
            $hide_host = true;
            $input_host = new html_hiddenfield(array(
                'name' => '_host', 'id' => 'rcmloginhost', 'value' => $host) + $attrib);
        }
        else if (empty($default_host)) {
            $input_host = new html_inputfield(array('name' => '_host', 'id' => 'rcmloginhost')
                + $attrib + $host_attrib);
        }

        $form_name  = !empty($attrib['form']) ? $attrib['form'] : 'form';
        $this->add_gui_object('loginform', $form_name);

        // create HTML table with two cols
        $table = new html_table(array('cols' => 2));

        $table->add('title', html::label('rcmloginuser', Q(rcube_label('username'))));
        $table->add('input', $input_user->show(get_input_value('_user', RCUBE_INPUT_GPC)));

        $table->add('title', html::label('rcmloginpwd', Q(rcube_label('password'))));
        $table->add('input', $input_pass->show());

        // add host selection row
        if (is_object($input_host) && !$hide_host) {
            $table->add('title', html::label('rcmloginhost', Q(rcube_label('server'))));
            $table->add('input', $input_host->show(get_input_value('_host', RCUBE_INPUT_GPC)));
        }

        $out  = $input_task->show();
        $out .= $input_action->show();
        $out .= $input_tzone->show();
        $out .= $input_dst->show();
        $out .= $input_url->show();
        $out .= $table->show();

        if ($hide_host) {
            $out .= $input_host->show();
        }

        // surround html output with a form tag
        if (empty($attrib['form'])) {
            $out = $this->form_tag(array('name' => $form_name, 'method' => 'post'), $out);
        }

        return $out;
    }


    /**
     * GUI object 'preloader'
     * Loads javascript code for images preloading
     *
     * @param array Named parameters
     * @return void
     */
    private function preloader($attrib)
    {
        $images = preg_split('/[\s\t\n,]+/', $attrib['images'], -1, PREG_SPLIT_NO_EMPTY);
        $images = array_map(array($this, 'abs_url'), $images);

        if (empty($images) || $this->app->task == 'logout')
            return;

        $this->add_script('var images = ' . json_serialize($images) .';
            for (var i=0; i<images.length; i++) {
                img = new Image();
                img.src = images[i];
            }', 'docready');
    }


    /**
     * GUI object 'searchform'
     * Returns code for search function
     *
     * @param array Named parameters
     * @return string HTML code for the gui object
     */
    private function search_form($attrib)
    {
        // add some labels to client
        $this->add_label('searching');

        $attrib['name'] = '_q';

        if (empty($attrib['id'])) {
            $attrib['id'] = 'rcmqsearchbox';
        }
        if ($attrib['type'] == 'search' && !$this->browser->khtml) {
            unset($attrib['type'], $attrib['results']);
        }

        $input_q = new html_inputfield($attrib);
        $out = $input_q->show();

        $this->add_gui_object('qsearchbox', $attrib['id']);

        // add form tag around text field
        if (empty($attrib['form'])) {
            $out = $this->form_tag(array(
                'name' => "rcmqsearchform",
                'onsubmit' => JS_OBJECT_NAME . ".command('search');return false;",
                'style' => "display:inline"),
                $out);
        }

        return $out;
    }


    /**
     * Builder for GUI object 'message'
     *
     * @param array Named tag parameters
     * @return string HTML code for the gui object
     */
    private function message_container($attrib)
    {
        if (isset($attrib['id']) === false) {
            $attrib['id'] = 'rcmMessageContainer';
        }

        $this->add_gui_object('message', $attrib['id']);
        return html::div($attrib, "");
    }


    /**
     * GUI object 'charsetselector'
     *
     * @param array Named parameters for the select tag
     * @return string HTML code for the gui object
     */
    function charset_selector($attrib)
    {
        // pass the following attributes to the form class
        $field_attrib = array('name' => '_charset');
        foreach ($attrib as $attr => $value) {
            if (in_array($attr, array('id', 'name', 'class', 'style', 'size', 'tabindex'))) {
                $field_attrib[$attr] = $value;
            }
        }

        $charsets = array(
            'UTF-8'        => 'UTF-8 ('.rcube_label('unicode').')',
            'US-ASCII'     => 'ASCII ('.rcube_label('english').')',
            'ISO-8859-1'   => 'ISO-8859-1 ('.rcube_label('westerneuropean').')',
            'ISO-8859-2'   => 'ISO-8859-2 ('.rcube_label('easterneuropean').')',
            'ISO-8859-4'   => 'ISO-8859-4 ('.rcube_label('baltic').')',
            'ISO-8859-5'   => 'ISO-8859-5 ('.rcube_label('cyrillic').')',
            'ISO-8859-6'   => 'ISO-8859-6 ('.rcube_label('arabic').')',
            'ISO-8859-7'   => 'ISO-8859-7 ('.rcube_label('greek').')',
            'ISO-8859-8'   => 'ISO-8859-8 ('.rcube_label('hebrew').')',
            'ISO-8859-9'   => 'ISO-8859-9 ('.rcube_label('turkish').')',
            'ISO-8859-10'   => 'ISO-8859-10 ('.rcube_label('nordic').')',
            'ISO-8859-11'   => 'ISO-8859-11 ('.rcube_label('thai').')',
            'ISO-8859-13'   => 'ISO-8859-13 ('.rcube_label('baltic').')',
            'ISO-8859-14'   => 'ISO-8859-14 ('.rcube_label('celtic').')',
            'ISO-8859-15'   => 'ISO-8859-15 ('.rcube_label('westerneuropean').')',
            'ISO-8859-16'   => 'ISO-8859-16 ('.rcube_label('southeasterneuropean').')',
            'WINDOWS-1250' => 'Windows-1250 ('.rcube_label('easterneuropean').')',
            'WINDOWS-1251' => 'Windows-1251 ('.rcube_label('cyrillic').')',
            'WINDOWS-1252' => 'Windows-1252 ('.rcube_label('westerneuropean').')',
            'WINDOWS-1253' => 'Windows-1253 ('.rcube_label('greek').')',
            'WINDOWS-1254' => 'Windows-1254 ('.rcube_label('turkish').')',
            'WINDOWS-1255' => 'Windows-1255 ('.rcube_label('hebrew').')',
            'WINDOWS-1256' => 'Windows-1256 ('.rcube_label('arabic').')',
            'WINDOWS-1257' => 'Windows-1257 ('.rcube_label('baltic').')',
            'WINDOWS-1258' => 'Windows-1258 ('.rcube_label('vietnamese').')',
            'ISO-2022-JP'  => 'ISO-2022-JP ('.rcube_label('japanese').')',
            'ISO-2022-KR'  => 'ISO-2022-KR ('.rcube_label('korean').')',
            'ISO-2022-CN'  => 'ISO-2022-CN ('.rcube_label('chinese').')',
            'EUC-JP'       => 'EUC-JP ('.rcube_label('japanese').')',
            'EUC-KR'       => 'EUC-KR ('.rcube_label('korean').')',
            'EUC-CN'       => 'EUC-CN ('.rcube_label('chinese').')',
            'BIG5'         => 'BIG5 ('.rcube_label('chinese').')',
            'GB2312'       => 'GB2312 ('.rcube_label('chinese').')',
        );

        if (!empty($_POST['_charset']))
	        $set = $_POST['_charset'];
	    else if (!empty($attrib['selected']))
	        $set = $attrib['selected'];
	    else
	        $set = $this->get_charset();

	    $set = strtoupper($set);
	    if (!isset($charsets[$set]))
	        $charsets[$set] = $set;

        $select = new html_select($field_attrib);
        $select->add(array_values($charsets), array_keys($charsets));

        return $select->show($set);
    }

}  // end class rcube_template