summaryrefslogtreecommitdiff
path: root/lib/util.php
blob: 97a36296cffc548d111556b364767d54e3fe4f8e (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
<?php
/*
 * Laconica - a distributed open-source microblogging tool
 * Copyright (C) 2008, Controlez-Vous, Inc.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

/* XXX: break up into separate modules (HTTP, HTML, user, files) */

# Show a server error

function common_server_error($msg, $code=500) {
	static $status = array(500 => 'Internal Server Error',
						   501 => 'Not Implemented',
						   502 => 'Bad Gateway',
						   503 => 'Service Unavailable',
						   504 => 'Gateway Timeout',
						   505 => 'HTTP Version Not Supported');

	if (!array_key_exists($code, $status)) {
		$code = 500;
	}

	$status_string = $status[$code];

	header('HTTP/1.1 '.$code.' '.$status_string);
	header('Content-type: text/plain');

	print $msg;
	print "\n";
	exit();
}

# Show a user error
function common_user_error($msg, $code=400) {
	static $status = array(400 => 'Bad Request',
						   401 => 'Unauthorized',
						   402 => 'Payment Required',
						   403 => 'Forbidden',
						   404 => 'Not Found',
						   405 => 'Method Not Allowed',
						   406 => 'Not Acceptable',
						   407 => 'Proxy Authentication Required',
						   408 => 'Request Timeout',
						   409 => 'Conflict',
						   410 => 'Gone',
						   411 => 'Length Required',
						   412 => 'Precondition Failed',
						   413 => 'Request Entity Too Large',
						   414 => 'Request-URI Too Long',
						   415 => 'Unsupported Media Type',
						   416 => 'Requested Range Not Satisfiable',
						   417 => 'Expectation Failed');

	if (!array_key_exists($code, $status)) {
		$code = 400;
	}

	$status_string = $status[$code];

	header('HTTP/1.1 '.$code.' '.$status_string);

	common_show_header('Error');
	common_element('div', array('class' => 'error'), $msg);
	common_show_footer();
}

$xw = null;

# Start an HTML element
function common_element_start($tag, $attrs=NULL) {
	global $xw;
	$xw->startElement($tag);
	if (is_array($attrs)) {
		foreach ($attrs as $name => $value) {
			$xw->writeAttribute($name, $value);
		}
	} else if (is_string($attrs)) {
		$xw->writeAttribute('class', $attrs);
	}
}

function common_element_end($tag) {
	static $empty_tag = array('base', 'meta', 'link', 'hr',
							  'br', 'param', 'img', 'area',
							  'input', 'col');
	global $xw;
	# XXX: check namespace
	if (in_array($tag, $empty_tag)) {
		$xw->endElement();
	} else {
		$xw->fullEndElement();
	}
}

function common_element($tag, $attrs=NULL, $content=NULL) {
	common_element_start($tag, $attrs);
	global $xw;
	if ($content) {
		$xw->text($content);
	}
	common_element_end($tag);
}

function common_start_xml($doc=NULL, $public=NULL, $system=NULL) {
	global $xw;
	$xw = new XMLWriter();
	$xw->openURI('php://output');
	$xw->setIndent(true);
	$xw->startDocument('1.0', 'UTF-8');
	if ($doc) {
		$xw->writeDTD($doc, $public, $system);
	}
}

function common_end_xml() {
	global $xw;
	$xw->endDocument();
	$xw->flush();
}

define('PAGE_TYPE_PREFS', 'text/html,application/xhtml+xml,application/xml;q=0.3,text/xml;q=0.2');

function common_show_header($pagetitle, $callable=NULL, $data=NULL, $headercall=NULL) {
	global $config, $xw;

	$httpaccept = isset($_SERVER['HTTP_ACCEPT']) ? $_SERVER['HTTP_ACCEPT'] : NULL;

	# XXX: allow content negotiation for RDF, RSS, or XRDS

	$type = common_negotiate_type(common_accept_to_prefs($httpaccept),
								  common_accept_to_prefs(PAGE_TYPE_PREFS));

	if (!$type) {
		common_user_error(_('This page is not available in a media type you accept'), 406);
		exit(0);
	}

	header('Content-Type: '.$type);

	common_start_xml('html',
					 '-//W3C//DTD XHTML 1.0 Strict//EN',
					 'http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd');

	# FIXME: correct language for interface

	common_element_start('html', array('xmlns' => 'http://www.w3.org/1999/xhtml',
									   'xml:lang' => 'en',
									   'lang' => 'en'));

	common_element_start('head');
	common_element('title', NULL,
				   $pagetitle . " - " . $config['site']['name']);
	common_element('link', array('rel' => 'stylesheet',
								 'type' => 'text/css',
								 'href' => theme_path('display.css'),
								 'media' => 'screen, projection, tv'));
	foreach (array(6,7) as $ver) {
		if (file_exists(theme_file('ie'.$ver.'.css'))) {
			# Yes, IE people should be put in jail.
			$xw->writeComment('[if lte IE '.$ver.']><link rel="stylesheet" type="text/css" '.
							  'href="'.theme_path('ie'.$ver.'.css').'" /><![endif]');
		}
	}

	common_element('script', array('type' => 'text/javascript',
								   'src' => common_path('js/jquery.min.js')),
				   ' ');
	common_element('script', array('type' => 'text/javascript',
								   'src' => common_path('js/util.js')),
				   ' ');

	if ($callable) {
		if ($data) {
			call_user_func($callable, $data);
		} else {
			call_user_func($callable);
		}
	}
	common_element_end('head');
	common_element_start('body');
	common_element_start('div', array('id' => 'wrap'));
	common_element_start('div', array('id' => 'header'));
	common_nav_menu();
	if ((is_string($config['site']['logo']) && (strlen($config['site']['logo']) > 0))
		|| file_exists(theme_file('logo.png')))
	{
		common_element_start('a', array('href' => common_local_url('public')));
		common_element('img', array('src' => ($config['site']['logo']) ?
									($config['site']['logo']) : theme_path('logo.png'),
									'alt' => $config['site']['name'],
									'id' => 'logo'));
		common_element_end('a');
	} else {
		common_element_start('p', array('id' => 'branding'));
		common_element('a', array('href' => common_local_url('public')),
					   $config['site']['name']);
		common_element_end('p');
	}

	common_element('h1', 'pagetitle', $pagetitle);

	if ($headercall) {
		if ($data) {
			call_user_func($headercall, $data);
		} else {
			call_user_func($headercall);
		}
	}
	common_element_end('div');
	common_element_start('div', array('id' => 'content'));
}

function common_show_footer() {
	global $xw, $config;
	common_element_end('div'); # content div
	common_foot_menu();
	common_element_start('div', array('id' => 'footer'));
	common_element_start('div', 'laconica');
	if (common_config('site', 'broughtby')) {
		$instr = _('**%%site.name%%** is a microblogging service brought to you by [%%site.broughtby%%](%%site.broughtbyurl%%). ');
	} else {
		$instr = _('**%%site.name%%** is a microblogging service. ');
	}
	$instr .= sprintf(_('It runs the [Laconica](http://laconi.ca/) microblogging software, version %s, available under the [GNU Affero General Public License](http://www.fsf.org/licensing/licenses/agpl-3.0.html).'), LACONICA_VERSION);
    $output = common_markup_to_html($instr);
    common_raw($output);
	common_element_end('div');
	common_element('img', array('id' => 'cc',
								'src' => $config['license']['image'],
								'alt' => $config['license']['title']));
	common_element_start('p');
	common_text(_('Unless otherwise specified, contents of this site are copyright by the contributors and available under the '));
	common_element('a', array('class' => 'license',
							  'rel' => 'license',
							  href => $config['license']['url']),
				   $config['license']['title']);
	common_text(_('. Contributors should be attributed by full name or nickname.'));
	common_element_end('p');
	common_element_end('div');
	common_element_end('div');
	common_element_end('body');
	common_element_end('html');
	common_end_xml();
}

function common_text($txt) {
	global $xw;
	$xw->text($txt);
}

function common_raw($xml) {
	global $xw;
	$xw->writeRaw($xml);
}

function common_nav_menu() {
	$user = common_current_user();
	common_element_start('ul', array('id' => 'nav'));
	if ($user) {
		common_menu_item(common_local_url('all', array('nickname' => $user->nickname)),
						 _('Home'));
	}
	common_menu_item(common_local_url('public'), _('Public'));
	common_menu_item(common_local_url('peoplesearch'), _('Search'));
	common_menu_item(common_local_url('doc', array('title' => 'help')),
					 _('Help'));
	if ($user) {
		common_menu_item(common_local_url('profilesettings'),
						 _('Settings'));
		common_menu_item(common_local_url('logout'),
						 _('Logout'));
	} else {
		common_menu_item(common_local_url('login'), _('Login'));
		common_menu_item(common_local_url('register'), _('Register'));
		common_menu_item(common_local_url('openidlogin'), _('OpenID'));
	}
	common_element_end('ul');
}

function common_foot_menu() {
	common_element_start('ul', array('id' => 'nav_sub'));
	common_menu_item(common_local_url('doc', array('title' => 'about')),
					 _('About'));
	common_menu_item(common_local_url('doc', array('title' => 'faq')),
					 _('FAQ'));
	common_menu_item(common_local_url('doc', array('title' => 'privacy')),
					 _('Privacy'));
	common_menu_item(common_local_url('doc', array('title' => 'source')),
					 _('Source'));
	common_menu_item(common_local_url('doc', array('title' => 'contact')),
					 _('Contact'));
	common_element_end('ul');
}

function common_menu_item($url, $text, $title=NULL, $is_selected=false) {
	$lattrs = array();
	if ($is_selected) {
		$lattrs['class'] = 'current';
	}
	common_element_start('li', $lattrs);
	$attrs['href'] = $url;
	if ($title) {
		$attrs['title'] = $title;
	}
	common_element('a', $attrs, $text);
	common_element_end('li');
}

function common_input($id, $label, $value=NULL,$instructions=NULL) {
	common_element_start('p');
	common_element('label', array('for' => $id), $label);
	$attrs = array('name' => $id,
				   'type' => 'text',
				   'class' => 'input_text',
				   'id' => $id);
	if ($value) {
		$attrs['value'] = htmlspecialchars($value);
	}
	common_element('input', $attrs);
	if ($instructions) {
		common_element('span', 'input_instructions', $instructions);
	}
	common_element_end('p');
}

function common_checkbox($id, $label, $checked=false, $instructions=NULL, $value='true')
{
	common_element_start('p');
	$attrs = array('name' => $id,
				   'type' => 'checkbox',
				   'class' => 'checkbox',
				   'id' => $id);
	if ($value) {
		$attrs['value'] = htmlspecialchars($value);
	}
	if ($checked) {
		$attrs['checked'] = 'checked';
	}
	common_element('input', $attrs);
	# XXX: use a <label>
	common_text(' ');
	common_element('span', 'checkbox_label', $label);
	common_text(' ');
	if ($instructions) {
		common_element('span', 'input_instructions', $instructions);
	}
	common_element_end('p');
}

function common_hidden($id, $value) {
	common_element('input', array('name' => $id,
								  'type' => 'hidden',
								  'id' => $id,
								  'value' => $value));
}

function common_password($id, $label, $instructions=NULL) {
	common_element_start('p');
	common_element('label', array('for' => $id), $label);
	$attrs = array('name' => $id,
				   'type' => 'password',
				   'class' => 'password',
				   'id' => $id);
	common_element('input', $attrs);
	if ($instructions) {
		common_element('span', 'input_instructions', $instructions);
	}
	common_element_end('p');
}

function common_submit($id, $label) {
	global $xw;
	common_element_start('p');
	common_element('input', array('type' => 'submit',
								  'id' => $id,
								  'name' => $id,
								  'class' => 'submit',
								  'value' => $label));
	common_element_end('p');
}

function common_textarea($id, $label, $content=NULL, $instructions=NULL) {
	common_element_start('p');
	common_element('label', array('for' => $id), $label);
	common_element('textarea', array('rows' => 3,
									 'cols' => 40,
									 'name' => $id,
									 'id' => $id),
				   ($content) ? $content : '');
	if ($instructions) {
		common_element('span', 'input_instructions', $instructions);
	}
	common_element_end('p');
}

# salted, hashed passwords are stored in the DB

function common_munge_password($password, $id) {
	return md5($password . $id);
}

# check if a username exists and has matching password
function common_check_user($nickname, $password) {
	$user = User::staticGet('nickname', $nickname);
	if (is_null($user)) {
		return false;
	} else {
		if (0 == strcmp(common_munge_password($password, $user->id),
						$user->password)) {
			return $user;
		} else {
			return false;
		}
	}
}

# is the current user logged in?
function common_logged_in() {
	return (!is_null(common_current_user()));
}

function common_have_session() {
	return (0 != strcmp(session_id(), ''));
}

function common_ensure_session() {
	if (!common_have_session()) {
		@session_start();
	}
}

# Three kinds of arguments:
# 1) a user object
# 2) a nickname
# 3) NULL to clear

function common_set_user($user) {
	if (is_null($user) && common_have_session()) {
		unset($_SESSION['userid']);
		return true;
	} else if (is_string($user)) {
		$nickname = $user;
		$user = User::staticGet('nickname', $nickname);
	} else if (!($user instanceof User)) {
		return false;
	}

	if ($user) {
		common_ensure_session();
		$_SESSION['userid'] = $user->id;
		return $user;
	}
	return false;
}

function common_set_cookie($key, $value, $expiration=0) {
	$path = common_config('site', 'path');
	$server = common_config('site', 'server');

	if ($path && ($path != '/')) {
		$cookiepath = '/' . $path . '/';
	} else {
		$cookiepath = '/';
	}
	return setcookie($key,
	                 $value,
	          		 $expiration,
			  		 $cookiepath,
			  	     $server);
}

define('REMEMBERME', 'rememberme');
define('REMEMBERME_EXPIRY', 30 * 24 * 60 * 60);

function common_rememberme($user=NULL) {
	if (!$user) {
		$user = common_current_user();
		if (!$user) {
			common_debug('No current user to remember', __FILE__);
			return false;
		}
	}
	$rm = new Remember_me();
	$rm->code = common_good_rand(16);
	$rm->user_id = $user->id;
	$result = $rm->insert();
	if (!$result) {
		common_log_db_error($rm, 'INSERT', __FILE__);
		common_debug('Error adding rememberme record for ' . $user->nickname, __FILE__);
		return false;
	}
	common_log(LOG_INFO, 'adding rememberme cookie for ' . $user->nickname);
	common_set_cookie(REMEMBERME,
					  implode(':', array($rm->user_id, $rm->code)),
					  time() + REMEMBERME_EXPIRY);
	return true;
}

function common_remembered_user() {
	$user = NULL;
	# Try to remember
	$packed = $_COOKIE[REMEMBERME];
	if ($packed) {
		list($id, $code) = explode(':', $packed);
		if ($id && $code) {
			$rm = Remember_me::staticGet($code);
			if ($rm && ($rm->user_id == $id)) {
				$user = User::staticGet($rm->user_id);
				if ($user) {
					# successful!
					$result = $rm->delete();
					if (!$result) {
						common_log_db_error($rm, 'DELETE', __FILE__);
						$user = NULL;
					} else {
						common_log(LOG_INFO, 'logging in ' . $user->nickname . ' using rememberme code ' . $rm->code);
						common_set_user($user->nickname);
						common_real_login(false);
						# We issue a new cookie, so they can log in
						# automatically again after this session
						common_rememberme($user);
					}
				}
			}
		}
	}
	return $user;
}

# must be called with a valid user!

function common_forgetme() {
	common_set_cookie(REMEMBERME, '', 0);
}

# who is the current user?
function common_current_user() {
	if ($_REQUEST[session_name()]) {
		common_ensure_session();
		$id = $_SESSION['userid'];
		if ($id) {
			# note: this should cache
			$user = User::staticGet($id);
			return $user;
		}
	}
	# that didn't work; try to remember
	$user = common_remembered_user();
	return $user;
}

# Logins that are 'remembered' aren't 'real' -- they're subject to
# cookie-stealing. So, we don't let them do certain things. New reg,
# OpenID, and password logins _are_ real.

function common_real_login($real=true) {
	common_ensure_session();
	$_SESSION['real_login'] = $real;
}

function common_is_real_login() {
	return common_logged_in() && $_SESSION['real_login'];
}

# get canonical version of nickname for comparison
function common_canonical_nickname($nickname) {
	# XXX: UTF-8 canonicalization (like combining chars)
	return strtolower($nickname);
}

# get canonical version of email for comparison
function common_canonical_email($email) {
	# XXX: canonicalize UTF-8
	# XXX: lcase the domain part
	return $email;
}

define('URL_REGEX', '^|[ \t\r\n])((ftp|http|https|gopher|mailto|news|nntp|telnet|wais|file|prospero|aim|webcal):(([A-Za-z0-9$_.+!*(),;/?:@&~=-])|%[A-Fa-f0-9]{2}){2,}(#([a-zA-Z0-9][a-zA-Z0-9$_.+!*(),;/?:@&~=%-]*))?([A-Za-z0-9$_+!*();/?:~-]))');

function common_render_content($text, $notice) {
	$r = htmlspecialchars($text);
	$id = $notice->profile_id;
	$r = preg_replace('@https?://\S+@', '<a href="\0" class="extlink">\0</a>', $r);
	$r = preg_replace('/(^|\s+)@([a-z0-9]{1,64})/e', "'\\1@'.common_at_link($id, '\\2')", $r);
	# XXX: # tags
	# XXX: machine tags
	return $r;
}

function common_at_link($sender_id, $nickname) {
	$sender = Profile::staticGet($sender_id);
	$recipient = common_relative_profile($sender, $nickname);
	if ($recipient) {
		return '<a href="'.htmlspecialchars($recipient->profileurl).'" class="atlink">'.$nickname.'</a>';
	} else {
		return $nickname;
	}
}

function common_relative_profile($sender, $nickname, $dt=NULL) {
	# Try to find profiles this profile is subscribed to that have this nickname
	$recipient = new Profile();
	# XXX: use a join instead of a subquery
	$recipient->whereAdd('EXISTS (SELECT subscribed from subscription where subscriber = '.$sender_id.' and subscribed = id)', 'AND');
	$recipient->whereAdd('nickname = "' . trim($nickname) . '"', 'AND');
	if ($recipient->find(TRUE)) {
		# XXX: should probably differentiate between profiles with
		# the same name by date of most recent update
		return $recipient;
	}
	# Try to find profiles that listen to this profile and that have this nickname
	$recipient = new Profile();
	# XXX: use a join instead of a subquery
	$recipient->whereAdd('EXISTS (SELECT subscriber from subscription where subscribed = '.$sender_id.' and subscriber = id)', 'AND');
	$recipient->whereAdd('nickname = "' . trim($nickname) . '"', 'AND');
	if ($recipient->find(TRUE)) {
		# XXX: should probably differentiate between profiles with
		# the same name by date of most recent update
		return $recipient;
	}
	# If this is a local user, try to find a local user with that nickname.
	$sender = User::staticGet($sender->id);
	if ($sender) {
		$recipient_user = User::staticGet('nickname', $nickname);
		if ($recipient_user) {
			return $recipient_user->getProfile();
		}
	}
	# Otherwise, no links. @messages from local users to remote users,
	# or from remote users to other remote users, are just
	# outside our ability to make intelligent guesses about
	return NULL;
}

// where should the avatar go for this user?

function common_avatar_filename($id, $extension, $size=NULL, $extra=NULL) {
	global $config;

	if ($size) {
		return $id . '-' . $size . (($extra) ? ('-' . $extra) : '') . $extension;
	} else {
		return $id . '-original' . (($extra) ? ('-' . $extra) : '') . $extension;
	}
}

function common_avatar_path($filename) {
	global $config;
	return INSTALLDIR . '/avatar/' . $filename;
}

function common_avatar_url($filename) {
	return common_path('avatar/'.$filename);
}

function common_avatar_display_url($avatar) {
	$server = common_config('avatar', 'server');
	if ($server) {
		return 'http://'.$server.'/'.$avatar->filename;
	} else {
		return $avatar->url;
	}
}

function common_default_avatar($size) {
	static $sizenames = array(AVATAR_PROFILE_SIZE => 'profile',
							  AVATAR_STREAM_SIZE => 'stream',
							  AVATAR_MINI_SIZE => 'mini');
	return theme_path('default-avatar-'.$sizenames[$size].'.png');
}

function common_local_url($action, $args=NULL) {
	global $config;
	if ($config['site']['fancy']) {
		return common_fancy_url($action, $args);
	} else {
		return common_simple_url($action, $args);
	}
}

function common_fancy_url($action, $args=NULL) {
	switch (strtolower($action)) {
	 case 'public':
		if ($args && $args['page']) {
			return common_path('?page=' . $args['page']);
		} else {
			return common_path('');
		}
	 case 'publicrss':
		return common_path('rss');
	 case 'publicxrds':
		return common_path('xrds');
	 case 'doc':
		return common_path('doc/'.$args['title']);
	 case 'login':
	 case 'logout':
	 case 'register':
	 case 'subscribe':
	 case 'unsubscribe':
		return common_path('main/'.$action);
	 case 'remotesubscribe':
		if ($args && $args['nickname']) {
			return common_path('main/remote?nickname=' . $args['nickname']);
		} else {
			return common_path('main/remote');
		}
	 case 'openidlogin':
		return common_path('main/openid');
	 case 'avatar':
	 case 'password':
		return common_path('settings/'.$action);
	 case 'profilesettings':
		return common_path('settings/profile');
	 case 'emailsettings':
		return common_path('settings/email');
	 case 'openidsettings':
		return common_path('settings/openid');
	 case 'newnotice':
		if ($args && $args['replyto']) {
			return common_path('notice/new?replyto='.$args['replyto']);
		} else {
			return common_path('notice/new');
		}
	 case 'shownotice':
		return common_path('notice/'.$args['notice']);
	 case 'xrds':
	 case 'foaf':
		return common_path($args['nickname'].'/'.$action);
	 case 'subscriptions':
	 case 'subscribers':
	 case 'all':
	 case 'replies':
		if ($args && $args['page']) {
			return common_path($args['nickname'].'/'.$action.'?page=' . $args['page']);
		} else {
			return common_path($args['nickname'].'/'.$action);
		}
	 case 'allrss':
		return common_path($args['nickname'].'/all/rss');
	 case 'repliesrss':
		return common_path($args['nickname'].'/replies/rss');
	 case 'userrss':
		return common_path($args['nickname'].'/rss');
	 case 'showstream':
		if ($args && $args['page']) {
			return common_path($args['nickname'].'?page=' . $args['page']);
		} else {
			return common_path($args['nickname']);
		}
	 case 'confirmaddress':
		return common_path('main/confirmaddress/'.$args['code']);
	 case 'userbyid':
	 	return common_path('user/'.$args['id']);
	 case 'recoverpassword':
	    $path = 'main/recoverpassword';
	    if ($args['code']) {
	    	$path .= '/' . $args['code'];
		}
	    return common_path($path);
	 case 'imsettings':
	 	return common_path('settings/im');
	 case 'peoplesearch':
		return common_path('search/people' . (($args) ? ('?' . http_build_query($args)) : ''));
	 case 'noticesearch':
		return common_path('search/notice' . (($args) ? ('?' . http_build_query($args)) : ''));
	 case 'noticesearchrss':
		return common_path('search/notice/rss' . (($args) ? ('?' . http_build_query($args)) : ''));
	 case 'avatarbynickname':
		return common_path($args['nickname'].'/avatar/'.$args['size']);
	 default:
		return common_simple_url($action, $args);
	}
}

function common_simple_url($action, $args=NULL) {
	global $config;
	/* XXX: pretty URLs */
	$extra = '';
	if ($args) {
		foreach ($args as $key => $value) {
			$extra .= "&${key}=${value}";
		}
	}
	return common_path("index.php?action=${action}${extra}");
}

function common_path($relative) {
	global $config;
	$pathpart = ($config['site']['path']) ? $config['site']['path']."/" : '';
	return "http://".$config['site']['server'].'/'.$pathpart.$relative;
}

function common_date_string($dt) {
	// XXX: do some sexy date formatting
	// return date(DATE_RFC822, $dt);
	$t = strtotime($dt);
	$now = time();
	$diff = $now - $t;

	if ($now < $t) { # that shouldn't happen!
		return common_exact_date($dt);
	} else if ($diff < 60) {
		return _('a few seconds ago');
	} else if ($diff < 92) {
		return _('about a minute ago');
	} else if ($diff < 3300) {
		return sprintf(_('about %d minutes ago'), round($diff/60));
	} else if ($diff < 5400) {
		return _('about an hour ago');
	} else if ($diff < 22 * 3600) {
		return sprintf(_('about %d hours ago'), round($diff/3600));
	} else if ($diff < 37 * 3600) {
		return _('about a day ago');
	} else if ($diff < 24 * 24 * 3600) {
		return sprintf(_('about %d days ago'), round($diff/(24*3600)));
	} else if ($diff < 46 * 24 * 3600) {
		return _('about a month ago');
	} else if ($diff < 330 * 24 * 3600) {
		return sprintf(_('about %d months ago'), round($diff/(30*24*3600)));
	} else if ($diff < 480 * 24 * 3600) {
		return _('about a year ago');
	} else {
		return common_exact_date($dt);
	}
}

function common_exact_date($dt) {
	$t = strtotime($dt);
	return date(DATE_RFC850, $t);
}

function common_date_w3dtf($dt) {
	$t = strtotime($dt);
	return date(DATE_W3C, $t);
}

function common_redirect($url, $code=307) {
	static $status = array(301 => "Moved Permanently",
						   302 => "Found",
						   303 => "See Other",
						   307 => "Temporary Redirect");
	header("Status: ${code} $status[$code]");
	header("Location: $url");

	common_start_xml('a',
					 '-//W3C//DTD XHTML 1.0 Strict//EN',
					 'http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd');
	common_element('a', array('href' => $url), $url);
	common_end_xml();
    exit;
}

function common_save_replies($notice) {
	# extract all @messages
	$cnt = preg_match_all('/(?:^|\s)@([a-z0-9]{1,64})/', $notice->content, $match);
	if (!$cnt) {
		return true;
	}
	$sender = Profile::staticGet($notice->profile_id);
	# store replied only for first @ (what user/notice what the reply directed,
	# we assume first @ is it)
	for ($i=0; $i<count($match[1]); $i++) {
		$nickname = $match[1][$i];
		$recipient = common_relative_profile($sender, $nickname, $notice->created);
		if (!$recipient) {
			continue;
		}
		if ($i == 0 && ($recipient->id != $sender->id)) { # Don't save reply to self
			$reply_for = $recipient;
			$recipient_notice = $reply_for->getCurrentNotice();
			$orig = clone($notice);
			$notice->reply_to = $recipient_notice->id;
			$notice->update($orig);
		}
		$reply = new Reply();
		$reply->notice_id = $notice->id;
		$reply->profile_id = $recipient->id;
		$id = $reply->insert();
		if (!$id) {
			$last_error = &PEAR::getStaticProperty('DB_DataObject','lastError');
			common_log(LOG_ERROR, 'DB error inserting reply: ' . $last_error->message);
			common_server_error(sprintf(_('DB error inserting reply: %s'), $last_error->message));
			return;
		}
	}
}

function common_broadcast_notice($notice, $remote=false) {
	if (common_config('queue', 'enabled')) {
		# Do it later!
		return common_enqueue_notice($notice);
	} else {
		return common_real_broadcast($notice, $remote);
	}
}

# Stick the notice on the queue

function common_enqueue_notice($notice) {
	$qi = new Queue_item();
	$qi->notice_id = $notice->id;
	$qi->created = $notice->created;
        $result = $qi->insert();
	if (!$result) {
	    $last_error = &PEAR::getStaticProperty('DB_DataObject','lastError');
	    common_log(LOG_ERROR, 'DB error inserting queue item: ' . $last_error->message);
	    return false;
	}
	common_log(LOG_DEBUG, 'complete queueing notice ID = ' . $notice->id);
	return $result;
}

function common_real_broadcast($notice, $remote=false) {
	$success = true;
	if (!$remote) {
		# Make sure we have the OMB stuff
		require_once(INSTALLDIR.'/lib/omb.php');
		$success = omb_broadcast_remote_subscribers($notice);
		if (!$success) {
			common_log(LOG_ERROR, 'Error in OMB broadcast for notice ' . $notice->id);
		}
	}
	if ($success) {
		require_once(INSTALLDIR.'/lib/jabber.php');
		$success = jabber_broadcast_notice($notice);
		if (!$success) {
			common_log(LOG_ERROR, 'Error in jabber broadcast for notice ' . $notice->id);
		}
	}
	// XXX: broadcast notices to SMS
	// XXX: broadcast notices to other IM
	return $success;
}

function common_broadcast_profile($profile) {
	// XXX: optionally use a queue system like http://code.google.com/p/microapps/wiki/NQDQ
	require_once(INSTALLDIR.'/lib/omb.php');
	omb_broadcast_profile($profile);
	// XXX: Other broadcasts...?
	return true;
}

function common_profile_url($nickname) {
	return common_local_url('showstream', array('nickname' => $nickname));
}

# Don't call if nobody's logged in

function common_notice_form($action=NULL, $content=NULL) {
	$user = common_current_user();
	assert(!is_null($user));
	common_element_start('form', array('id' => 'status_form',
									   'method' => 'post',
									   'action' => common_local_url('newnotice')));
	common_element_start('p');
	common_element('label', array('for' => 'status_textarea',
								  'id' => 'status_label'),
				   sprintf(_('What\'s up, %s?'), $user->nickname));
        common_element('span', array('id' => 'counter', 'class' => 'counter'), '140');
	common_element('textarea', array('id' => 'status_textarea',
									 'cols' => 60,
									 'rows' => 3,
									 'name' => 'status_textarea'),
				   ($content) ? $content : '');
	if ($action) {
		common_hidden('returnto', $action);
	}
	common_element('input', array('id' => 'status_submit',
								  'name' => 'status_submit',
								  'type' => 'submit',
								  'value' => _('Send')));
	common_element_end('p');
	common_element_end('form');
}

function common_mint_tag($extra) {
	global $config;
	return
	  'tag:'.$config['tag']['authority'].','.
	  $config['tag']['date'].':'.$config['tag']['prefix'].$extra;
}

# Should make up a reasonable root URL

function common_root_url() {
	return common_path('');
}

# returns $bytes bytes of random data as a hexadecimal string
# "good" here is a goal and not a guarantee

function common_good_rand($bytes) {
	# XXX: use random.org...?
	if (file_exists('/dev/urandom')) {
		return common_urandom($bytes);
	} else { # FIXME: this is probably not good enough
		return common_mtrand($bytes);
	}
}

function common_urandom($bytes) {
	$h = fopen('/dev/urandom', 'rb');
	# should not block
	$src = fread($h, $bytes);
	fclose($h);
	$enc = '';
	for ($i = 0; $i < $bytes; $i++) {
		$enc .= sprintf("%02x", (ord($src[$i])));
	}
	return $enc;
}

function common_mtrand($bytes) {
	$enc = '';
	for ($i = 0; $i < $bytes; $i++) {
		$enc .= sprintf("%02x", mt_rand(0, 255));
	}
	return $enc;
}

function common_set_returnto($url) {
	common_ensure_session();
	$_SESSION['returnto'] = $url;
}

function common_get_returnto() {
	common_ensure_session();
	return $_SESSION['returnto'];
}

function common_timestamp() {
	return date('YmdHis');
}

function common_ensure_syslog() {
	static $initialized = false;
	if (!$initialized) {
		global $config;
		define_syslog_variables();
		openlog($config['syslog']['appname'], 0, LOG_USER);
		$initialized = true;
	}
}

function common_log($priority, $msg, $filename=NULL) {
	$logfile = common_config('site', 'logfile');
	if ($logfile) {
		$log = fopen($logfile, "a");
		if ($log) {
			static $syslog_priorities = array('LOG_EMERG', 'LOG_ALERT', 'LOG_CRIT', 'LOG_ERR',
											  'LOG_WARNING', 'LOG_NOTICE', 'LOG_INFO', 'LOG_DEBUG');
			$output = date('Y-m-d H:i:s') . ' ' . $syslog_priorities[$priority] . ': ' . $msg . "\n";
			fwrite($log, $output);
			fclose($log);
		}
	} else {
		common_ensure_syslog();
		syslog($priority, $msg);
	}
}

function common_debug($msg, $filename=NULL) {
	if ($filename) {
		common_log(LOG_DEBUG, basename($filename).' - '.$msg);
	} else {
		common_log(LOG_DEBUG, $msg);
	}
}

function common_log_db_error(&$object, $verb, $filename=NULL) {
	$objstr = common_log_objstring($object);
	$last_error = &PEAR::getStaticProperty('DB_DataObject','lastError');
	common_log(LOG_ERR, $last_error->message . '(' . $verb . ' on ' . $objstr . ')', $filename);
}

function common_log_objstring(&$object) {
	if (is_null($object)) {
		return "NULL";
	}
	$arr = $object->toArray();
	$fields = array();
	foreach ($arr as $k => $v) {
		$fields[] = "$k='$v'";
	}
	$objstring = $object->tableName() . '[' . implode(',', $fields) . ']';
	return $objstring;
}

function common_valid_http_url($url) {
	return Validate::uri($url, array('allowed_schemes' => array('http', 'https')));
}

function common_valid_tag($tag) {
	if (preg_match('/^tag:(.*?),(\d{4}(-\d{2}(-\d{2})?)?):(.*)$/', $tag, $matches)) {
		return (Validate::email($matches[1]) ||
				preg_match('/^([\w-\.]+)$/', $matches[1]));
	}
	return false;
}

# Does a little before-after block for next/prev page

function common_pagination($have_before, $have_after, $page, $action, $args=NULL) {

	if ($have_before || $have_after) {
		common_element_start('div', array('id' => 'pagination'));
		common_element_start('ul', array('id' => 'nav_pagination'));
	}

	if ($have_before) {
		$pargs = array('page' => $page-1);
		$newargs = ($args) ? array_merge($args,$pargs) : $pargs;

		common_element_start('li', 'before');
		common_element('a', array('href' => common_local_url($action, $newargs)),
					   _('« After'));
		common_element_end('li');
	}

	if ($have_after) {
		$pargs = array('page' => $page+1);
		$newargs = ($args) ? array_merge($args,$pargs) : $pargs;
		common_element_start('li', 'after');
		common_element('a', array('href' => common_local_url($action, $newargs)),
						   _('Before »'));
		common_element_end('li');
	}

	if ($have_before || $have_after) {
		common_element_end('ul');
		common_element_end('div');
	}
}

/* Following functions are copied from MediaWiki GlobalFunctions.php
 * and written by Evan Prodromou. */

function common_accept_to_prefs($accept, $def = '*/*') {
	# No arg means accept anything (per HTTP spec)
	if(!$accept) {
		return array($def => 1);
	}

	$prefs = array();

	$parts = explode(',', $accept);

	foreach($parts as $part) {
		# FIXME: doesn't deal with params like 'text/html; level=1'
		@list($value, $qpart) = explode(';', $part);
		$match = array();
		if(!isset($qpart)) {
			$prefs[$value] = 1;
		} elseif(preg_match('/q\s*=\s*(\d*\.\d+)/', $qpart, $match)) {
			$prefs[$value] = $match[1];
		}
	}

	return $prefs;
}

function common_mime_type_match($type, $avail) {
	if(array_key_exists($type, $avail)) {
		return $type;
	} else {
		$parts = explode('/', $type);
		if(array_key_exists($parts[0] . '/*', $avail)) {
			return $parts[0] . '/*';
		} elseif(array_key_exists('*/*', $avail)) {
			return '*/*';
		} else {
			return NULL;
		}
	}
}

function common_negotiate_type($cprefs, $sprefs) {
	$combine = array();

	foreach(array_keys($sprefs) as $type) {
		$parts = explode('/', $type);
		if($parts[1] != '*') {
			$ckey = common_mime_type_match($type, $cprefs);
			if($ckey) {
				$combine[$type] = $sprefs[$type] * $cprefs[$ckey];
			}
		}
	}

	foreach(array_keys($cprefs) as $type) {
		$parts = explode('/', $type);
		if($parts[1] != '*' && !array_key_exists($type, $sprefs)) {
			$skey = common_mime_type_match($type, $sprefs);
			if($skey) {
				$combine[$type] = $sprefs[$skey] * $cprefs[$type];
			}
		}
	}

	$bestq = 0;
	$besttype = "text/html";

	foreach(array_keys($combine) as $type) {
		if($combine[$type] > $bestq) {
			$besttype = $type;
			$bestq = $combine[$type];
		}
	}

	return $besttype;
}

function common_config($main, $sub) {
	global $config;
	return $config[$main][$sub];
}

function common_copy_args($from) {
	$to = array();
	$strip = get_magic_quotes_gpc();
	foreach ($from as $k => $v) {
		$to[$k] = ($strip) ? stripslashes($v) : $v;
	}
	return $to;
}

function common_user_uri(&$user) {
	return common_local_url('userbyid', array('id' => $user->id));
}

function common_notice_uri(&$notice) {
	return common_local_url('shownotice',
		array('notice' => $notice->id));
}

# 36 alphanums - lookalikes (0, O, 1, I) = 32 chars = 5 bits

function common_confirmation_code($bits) {
	# 36 alphanums - lookalikes (0, O, 1, I) = 32 chars = 5 bits
	static $codechars = '23456789ABCDEFGHJKLMNPQRSTUVWXYZ';
	$chars = ceil($bits/5);
	$code = '';
	for ($i = 0; $i < $chars; $i++) {
		# XXX: convert to string and back
		$num = hexdec(common_good_rand(1));
		# XXX: randomness is too precious to throw away almost
		# 40% of the bits we get!
		$code .= $codechars[$num%32];
	}
	return $code;
}

# convert markup to HTML

function common_markup_to_html($c) {
	$c = preg_replace('/%%action.(\w+)%%/e', "common_local_url('\\1')", $c);
	$c = preg_replace('/%%doc.(\w+)%%/e', "common_local_url('doc', array('title'=>'\\1'))", $c);
	$c = preg_replace('/%%(\w+).(\w+)%%/e', 'common_config(\'\\1\', \'\\2\')', $c);
	return Markdown($c);
}

function common_profile_avatar_url($profile, $size=AVATAR_PROFILE_SIZE) {
	$avatar = $profile->getAvatar($size);
	if ($avatar) {
		return common_avatar_display_url($avatar);
	} else {
		return common_default_avatar($size);
	}
}