aboutsummaryrefslogtreecommitdiffhomepage
path: root/index.php
blob: ab51fa23b21bbc93941822094422f0a4d6c5c353 (plain) (blame)
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
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
<?php
/**
 * Shaarli v0.7.0 - Shaare your links...
 *
 * The personal, minimalist, super-fast, database free, bookmarking service.
 *
 * Friendly fork by the Shaarli community:
 *  - https://github.com/shaarli/Shaarli
 *
 * Original project by sebsauvage.net:
 *  - http://sebsauvage.net/wiki/doku.php?id=php:shaarli
 *  - https://github.com/sebsauvage/Shaarli
 *
 * Licence: http://www.opensource.org/licenses/zlib-license.php
 *
 * Requires: PHP 5.3.x
 */

// Set 'UTC' as the default timezone if it is not defined in php.ini
// See http://php.net/manual/en/datetime.configuration.php#ini.date.timezone
if (date_default_timezone_get() == '') {
    date_default_timezone_set('UTC');
}

/*
 * PHP configuration
 */
define('shaarli_version', '0.7.0');

// http://server.com/x/shaarli --> /shaarli/
define('WEB_PATH', substr($_SERVER['REQUEST_URI'], 0, 1+strrpos($_SERVER['REQUEST_URI'], '/', 0)));

// High execution time in case of problematic imports/exports.
ini_set('max_input_time','60');

// Try to set max upload file size and read
ini_set('memory_limit', '128M');
ini_set('post_max_size', '16M');
ini_set('upload_max_filesize', '16M');

// See all error except warnings
error_reporting(E_ALL^E_WARNING);
// See all errors (for debugging only)
//error_reporting(-1);


// Shaarli library
require_once 'application/ApplicationUtils.php';
require_once 'application/Cache.php';
require_once 'application/CachedPage.php';
require_once 'application/config/ConfigManager.php';
require_once 'application/config/ConfigPlugin.php';
require_once 'application/FeedBuilder.php';
require_once 'application/FileUtils.php';
require_once 'application/HttpUtils.php';
require_once 'application/LinkDB.php';
require_once 'application/LinkFilter.php';
require_once 'application/LinkUtils.php';
require_once 'application/NetscapeBookmarkUtils.php';
require_once 'application/PageBuilder.php';
require_once 'application/TimeZone.php';
require_once 'application/Url.php';
require_once 'application/Utils.php';
require_once 'application/PluginManager.php';
require_once 'application/Router.php';
require_once 'application/Updater.php';
require_once 'inc/rain.tpl.class.php';

// Ensure the PHP version is supported
try {
    ApplicationUtils::checkPHPVersion('5.3', PHP_VERSION);
} catch(Exception $exc) {
    header('Content-Type: text/plain; charset=utf-8');
    echo $exc->getMessage();
    exit;
}

// Force cookie path (but do not change lifetime)
$cookie = session_get_cookie_params();
$cookiedir = '';
if (dirname($_SERVER['SCRIPT_NAME']) != '/') {
    $cookiedir = dirname($_SERVER["SCRIPT_NAME"]).'/';
}
// Set default cookie expiration and path.
session_set_cookie_params($cookie['lifetime'], $cookiedir, $_SERVER['SERVER_NAME']);
// Set session parameters on server side.
// If the user does not access any page within this time, his/her session is considered expired.
define('INACTIVITY_TIMEOUT', 3600); // in seconds.
// Use cookies to store session.
ini_set('session.use_cookies', 1);
// Force cookies for session (phpsessionID forbidden in URL).
ini_set('session.use_only_cookies', 1);
// Prevent PHP form using sessionID in URL if cookies are disabled.
ini_set('session.use_trans_sid', false);

session_name('shaarli');
// Start session if needed (Some server auto-start sessions).
if (session_id() == '') {
    session_start();
}

// Regenerate session ID if invalid or not defined in cookie.
if (isset($_COOKIE['shaarli']) && !is_session_id_valid($_COOKIE['shaarli'])) {
    session_regenerate_id(true);
    $_COOKIE['shaarli'] = session_id();
}

$conf = new ConfigManager();
$conf->setEmpty('general.timezone', date_default_timezone_get());
$conf->setEmpty('general.title', 'Shared links on '. escape(index_url($_SERVER)));
RainTPL::$tpl_dir = $conf->get('resource.raintpl_tpl'); // template directory
RainTPL::$cache_dir = $conf->get('resource.raintpl_tmp'); // cache directory

$pluginManager = new PluginManager($conf);
$pluginManager->load($conf->get('general.enabled_plugins'));

date_default_timezone_set($conf->get('general.timezone', 'UTC'));

ob_start();  // Output buffering for the page cache.

// In case stupid admin has left magic_quotes enabled in php.ini:
if (get_magic_quotes_gpc())
{
    function stripslashes_deep($value) { $value = is_array($value) ? array_map('stripslashes_deep', $value) : stripslashes($value); return $value; }
    $_POST = array_map('stripslashes_deep', $_POST);
    $_GET = array_map('stripslashes_deep', $_GET);
    $_COOKIE = array_map('stripslashes_deep', $_COOKIE);
}

// Prevent caching on client side or proxy: (yes, it's ugly)
header("Last-Modified: " . gmdate("D, d M Y H:i:s") . " GMT");
header("Cache-Control: no-store, no-cache, must-revalidate");
header("Cache-Control: post-check=0, pre-check=0", false);
header("Pragma: no-cache");

if (! is_file($conf->getConfigFileExt())) {
    // Ensure Shaarli has proper access to its resources
    $errors = ApplicationUtils::checkResourcePermissions($conf);

    if ($errors != array()) {
        $message = '<p>Insufficient permissions:</p><ul>';

        foreach ($errors as $error) {
            $message .= '<li>'.$error.'</li>';
        }
        $message .= '</ul>';

        header('Content-Type: text/html; charset=utf-8');
        echo $message;
        exit;
    }

    // Display the installation form if no existing config is found
    install($conf);
}

// a token depending of deployment salt, user password, and the current ip
define('STAY_SIGNED_IN_TOKEN', sha1($conf->get('credentials.hash') . $_SERVER['REMOTE_ADDR'] . $conf->get('credentials.salt')));

// Sniff browser language and set date format accordingly.
if (isset($_SERVER['HTTP_ACCEPT_LANGUAGE'])) {
    autoLocale($_SERVER['HTTP_ACCEPT_LANGUAGE']);
}
header('Content-Type: text/html; charset=utf-8'); // We use UTF-8 for proper international characters handling.

/**
 * Checking session state (i.e. is the user still logged in)
 *
 * @param ConfigManager $conf The configuration manager.
 *
 * @return bool: true if the user is logged in, false otherwise.
 */
function setup_login_state($conf)
{
	if ($conf->get('security.open_shaarli')) {
	    return true;
	}
	$userIsLoggedIn = false; // By default, we do not consider the user as logged in;
	$loginFailure = false; // If set to true, every attempt to authenticate the user will fail. This indicates that an important condition isn't met.
	if (! $conf->exists('credentials.login')) {
	    $userIsLoggedIn = false;  // Shaarli is not configured yet.
	    $loginFailure = true;
	}
	if (isset($_COOKIE['shaarli_staySignedIn']) &&
	    $_COOKIE['shaarli_staySignedIn']===STAY_SIGNED_IN_TOKEN &&
	    !$loginFailure)
	{
	    fillSessionInfo($conf);
	    $userIsLoggedIn = true;
	}
	// If session does not exist on server side, or IP address has changed, or session has expired, logout.
	if (empty($_SESSION['uid'])
        || ($conf->get('security.session_protection_disabled') == false && $_SESSION['ip'] != allIPs())
        || time() >= $_SESSION['expires_on'])
	{
	    logout();
	    $userIsLoggedIn = false;
	    $loginFailure = true;
	}
	if (!empty($_SESSION['longlastingsession'])) {
	    $_SESSION['expires_on']=time()+$_SESSION['longlastingsession']; // In case of "Stay signed in" checked.
	}
	else {
	    $_SESSION['expires_on']=time()+INACTIVITY_TIMEOUT; // Standard session expiration date.
	}
	if (!$loginFailure) {
	    $userIsLoggedIn = true;
	}

	return $userIsLoggedIn;
}
$userIsLoggedIn = setup_login_state($conf);

/**
 * PubSubHubbub protocol support (if enabled)  [UNTESTED]
 * (Source: http://aldarone.fr/les-flux-rss-shaarli-et-pubsubhubbub/ )
 *
 * @param ConfigManager $conf Configuration Manager instance.
 */
function pubsubhub($conf)
{
    $pshUrl = $conf->get('config.PUBSUBHUB_URL');
    if (!empty($pshUrl))
    {
        include_once './publisher.php';
        $p = new Publisher($pshUrl);
        $topic_url = array (
            index_url($_SERVER).'?do=atom',
            index_url($_SERVER).'?do=rss'
        );
        $p->publish_update($topic_url);
    }
}

// ------------------------------------------------------------------------------------------
// Session management

// Returns the IP address of the client (Used to prevent session cookie hijacking.)
function allIPs()
{
    $ip = $_SERVER['REMOTE_ADDR'];
    // Then we use more HTTP headers to prevent session hijacking from users behind the same proxy.
    if (isset($_SERVER['HTTP_X_FORWARDED_FOR'])) { $ip=$ip.'_'.$_SERVER['HTTP_X_FORWARDED_FOR']; }
    if (isset($_SERVER['HTTP_CLIENT_IP'])) { $ip=$ip.'_'.$_SERVER['HTTP_CLIENT_IP']; }
    return $ip;
}

/**
 * Load user session.
 *
 * @param ConfigManager $conf Configuration Manager instance.
 */
function fillSessionInfo($conf)
{
	$_SESSION['uid'] = sha1(uniqid('',true).'_'.mt_rand()); // Generate unique random number (different than phpsessionid)
	$_SESSION['ip']=allIPs();                // We store IP address(es) of the client to make sure session is not hijacked.
	$_SESSION['username']= $conf->get('credentials.login');
	$_SESSION['expires_on']=time()+INACTIVITY_TIMEOUT;  // Set session expiration.
}

/**
 * Check that user/password is correct.
 *
 * @param string        $login    Username
 * @param string        $password User password
 * @param ConfigManager $conf     Configuration Manager instance.
 *
 * @return bool: authentication successful or not.
 */
function check_auth($login, $password, $conf)
{
    $hash = sha1($password . $login . $conf->get('credentials.salt'));
    if ($login == $conf->get('credentials.login') && $hash == $conf->get('credentials.hash'))
    {   // Login/password is correct.
		fillSessionInfo($conf);
        logm($conf->get('resource.log'), $_SERVER['REMOTE_ADDR'], 'Login successful');
        return true;
    }
    logm($conf->get('resource.log'), $_SERVER['REMOTE_ADDR'], 'Login failed for user '.$login);
    return false;
}

// Returns true if the user is logged in.
function isLoggedIn()
{
    global $userIsLoggedIn;
    return $userIsLoggedIn;
}

// Force logout.
function logout() {
    if (isset($_SESSION)) {
        unset($_SESSION['uid']);
        unset($_SESSION['ip']);
        unset($_SESSION['username']);
        unset($_SESSION['privateonly']);
    }
    setcookie('shaarli_staySignedIn', FALSE, 0, WEB_PATH);
}


// ------------------------------------------------------------------------------------------
// Brute force protection system
// Several consecutive failed logins will ban the IP address for 30 minutes.
if (!is_file($conf->get('resource.ban_file', 'data/ipbans.php'))) {
    // FIXME! globals
    file_put_contents(
        $conf->get('resource.ban_file', 'data/ipbans.php'),
        "<?php\n\$GLOBALS['IPBANS']=".var_export(array('FAILURES'=>array(),'BANS'=>array()),true).";\n?>"
    );
}
include $conf->get('resource.ban_file', 'data/ipbans.php');
/**
 * Signal a failed login. Will ban the IP if too many failures:
 *
 * @param ConfigManager $conf Configuration Manager instance.
 */
function ban_loginFailed($conf)
{
    $ip = $_SERVER['REMOTE_ADDR'];
    $trusted = $conf->get('security.trusted_proxies', array());
    if (in_array($ip, $trusted)) {
        $ip = getIpAddressFromProxy($_SERVER, $trusted);
        if (!$ip) {
            return;
        }
    }
    $gb = $GLOBALS['IPBANS'];
    if (! isset($gb['FAILURES'][$ip])) {
        $gb['FAILURES'][$ip]=0;
    }
    $gb['FAILURES'][$ip]++;
    if ($gb['FAILURES'][$ip] > ($conf->get('security.ban_after') - 1))
    {
        $gb['BANS'][$ip] = time() + $conf->get('security.ban_after', 1800);
        logm($conf->get('resource.log'), $_SERVER['REMOTE_ADDR'], 'IP address banned from login');
    }
    $GLOBALS['IPBANS'] = $gb;
    file_put_contents(
        $conf->get('resource.ban_file', 'data/ipbans.php'),
        "<?php\n\$GLOBALS['IPBANS']=".var_export($gb,true).";\n?>"
    );
}

/**
 * Signals a successful login. Resets failed login counter.
 *
 * @param ConfigManager $conf Configuration Manager instance.
 */
function ban_loginOk($conf)
{
    $ip = $_SERVER['REMOTE_ADDR'];
    $gb = $GLOBALS['IPBANS'];
    unset($gb['FAILURES'][$ip]); unset($gb['BANS'][$ip]);
    $GLOBALS['IPBANS'] = $gb;
    file_put_contents(
        $conf->get('resource.ban_file', 'data/ipbans.php'),
        "<?php\n\$GLOBALS['IPBANS']=".var_export($gb,true).";\n?>"
    );
}

/**
 * Checks if the user CAN login. If 'true', the user can try to login.
 *
 * @param ConfigManager $conf Configuration Manager instance.
 *
 * @return bool: true if the user is allowed to login.
 */
function ban_canLogin($conf)
{
    $ip=$_SERVER["REMOTE_ADDR"]; $gb=$GLOBALS['IPBANS'];
    if (isset($gb['BANS'][$ip]))
    {
        // User is banned. Check if the ban has expired:
        if ($gb['BANS'][$ip]<=time())
        {   // Ban expired, user can try to login again.
            logm($conf->get('resource.log'), $_SERVER['REMOTE_ADDR'], 'Ban lifted.');
            unset($gb['FAILURES'][$ip]); unset($gb['BANS'][$ip]);
            file_put_contents(
                $conf->get('resource.ban_file', 'data/ipbans.php'),
                "<?php\n\$GLOBALS['IPBANS']=".var_export($gb,true).";\n?>"
            );
            return true; // Ban has expired, user can login.
        }
        return false; // User is banned.
    }
    return true; // User is not banned.
}

// ------------------------------------------------------------------------------------------
// Process login form: Check if login/password is correct.
if (isset($_POST['login']))
{
    if (!ban_canLogin($conf)) die('I said: NO. You are banned for the moment. Go away.');
    if (isset($_POST['password'])
        && tokenOk($_POST['token'])
        && (check_auth($_POST['login'], $_POST['password'], $conf))
    ) {   // Login/password is OK.
        ban_loginOk($conf);
        // If user wants to keep the session cookie even after the browser closes:
        if (!empty($_POST['longlastingsession']))
        {
			setcookie('shaarli_staySignedIn', STAY_SIGNED_IN_TOKEN, time()+31536000, WEB_PATH);
            $_SESSION['longlastingsession']=31536000;  // (31536000 seconds = 1 year)
            $_SESSION['expires_on']=time()+$_SESSION['longlastingsession'];  // Set session expiration on server-side.

            $cookiedir = ''; if(dirname($_SERVER['SCRIPT_NAME'])!='/') $cookiedir=dirname($_SERVER["SCRIPT_NAME"]).'/';
            session_set_cookie_params($_SESSION['longlastingsession'],$cookiedir,$_SERVER['SERVER_NAME']); // Set session cookie expiration on client side
            // Note: Never forget the trailing slash on the cookie path!
            session_regenerate_id(true);  // Send cookie with new expiration date to browser.
        }
        else // Standard session expiration (=when browser closes)
        {
            $cookiedir = ''; if(dirname($_SERVER['SCRIPT_NAME'])!='/') $cookiedir=dirname($_SERVER["SCRIPT_NAME"]).'/';
            session_set_cookie_params(0,$cookiedir,$_SERVER['SERVER_NAME']); // 0 means "When browser closes"
            session_regenerate_id(true);
        }

        // Optional redirect after login:
        if (isset($_GET['post'])) {
            $uri = '?post='. urlencode($_GET['post']);
            foreach (array('description', 'source', 'title') as $param) {
                if (!empty($_GET[$param])) {
                    $uri .= '&'.$param.'='.urlencode($_GET[$param]);
                }
            }
            header('Location: '. $uri);
            exit;
        }

        if (isset($_GET['edit_link'])) {
            header('Location: ?edit_link='. escape($_GET['edit_link']));
            exit;
        }

        if (isset($_POST['returnurl'])) {
            // Prevent loops over login screen.
            if (strpos($_POST['returnurl'], 'do=login') === false) {
                header('Location: '. generateLocation($_POST['returnurl'], $_SERVER['HTTP_HOST']));
                exit;
            }
        }
        header('Location: ?'); exit;
    }
    else
    {
        ban_loginFailed($conf);
        $redir = '&username='. $_POST['login'];
        if (isset($_GET['post'])) {
            $redir .= '&post=' . urlencode($_GET['post']);
            foreach (array('description', 'source', 'title') as $param) {
                if (!empty($_GET[$param])) {
                    $redir .= '&' . $param . '=' . urlencode($_GET[$param]);
                }
            }
        }
        echo '<script>alert("Wrong login/password.");document.location=\'?do=login'.$redir.'\';</script>'; // Redirect to login screen.
        exit;
    }
}

// ------------------------------------------------------------------------------------------
// Misc utility functions:

// Convert post_max_size/upload_max_filesize (e.g. '16M') parameters to bytes.
function return_bytes($val)
{
    $val = trim($val); $last=strtolower($val[strlen($val)-1]);
    switch($last)
    {
        case 'g': $val *= 1024;
        case 'm': $val *= 1024;
        case 'k': $val *= 1024;
    }
    return $val;
}

// Try to determine max file size for uploads (POST).
// Returns an integer (in bytes)
function getMaxFileSize()
{
    $size1 = return_bytes(ini_get('post_max_size'));
    $size2 = return_bytes(ini_get('upload_max_filesize'));
    // Return the smaller of two:
    $maxsize = min($size1,$size2);
    // FIXME: Then convert back to readable notations ? (e.g. 2M instead of 2000000)
    return $maxsize;
}

// ------------------------------------------------------------------------------------------
// Token management for XSRF protection
// Token should be used in any form which acts on data (create,update,delete,import...).
if (!isset($_SESSION['tokens'])) $_SESSION['tokens']=array();  // Token are attached to the session.

/**
 * Returns a token.
 *
 * @param ConfigManager $conf Configuration Manager instance.
 *
 * @return string token.
 */
function getToken($conf)
{
    $rnd = sha1(uniqid('', true) .'_'. mt_rand() . $conf->get('credentials.salt'));  // We generate a random string.
    $_SESSION['tokens'][$rnd]=1;  // Store it on the server side.
    return $rnd;
}

// Tells if a token is OK. Using this function will destroy the token.
// true=token is OK.
function tokenOk($token)
{
    if (isset($_SESSION['tokens'][$token]))
    {
        unset($_SESSION['tokens'][$token]); // Token is used: destroy it.
        return true; // Token is OK.
    }
    return false; // Wrong token, or already used.
}

/**
 * Daily RSS feed: 1 RSS entry per day giving all the links on that day.
 * Gives the last 7 days (which have links).
 * This RSS feed cannot be filtered.
 *
 * @param ConfigManager $conf Configuration Manager instance.
 */
function showDailyRSS($conf) {
    // Cache system
    $query = $_SERVER['QUERY_STRING'];
    $cache = new CachedPage(
        $conf->get('config.PAGE_CACHE'),
        page_url($_SERVER),
        startsWith($query,'do=dailyrss') && !isLoggedIn()
    );
    $cached = $cache->cachedVersion();
    if (!empty($cached)) {
        echo $cached;
        exit;
    }

    // If cached was not found (or not usable), then read the database and build the response:
    // Read links from database (and filter private links if used it not logged in).
    $LINKSDB = new LinkDB(
        $conf->get('resource.datastore'),
        isLoggedIn(),
        $conf->get('privacy.hide_public_links'),
        $conf->get('redirector.url'),
        $conf->get('redirector.encode_url')
    );

    /* Some Shaarlies may have very few links, so we need to look
       back in time (rsort()) until we have enough days ($nb_of_days).
    */
    $linkdates = array();
    foreach ($LINKSDB as $linkdate => $value) {
        $linkdates[] = $linkdate;
    }
    rsort($linkdates);
    $nb_of_days = 7; // We take 7 days.
    $today = date('Ymd');
    $days = array();

    foreach ($linkdates as $linkdate) {
        $day = substr($linkdate, 0, 8); // Extract day (without time)
        if (strcmp($day,$today) < 0) {
            if (empty($days[$day])) {
                $days[$day] = array();
            }
            $days[$day][] = $linkdate;
        }

        if (count($days) > $nb_of_days) {
            break; // Have we collected enough days?
        }
    }

    // Build the RSS feed.
    header('Content-Type: application/rss+xml; charset=utf-8');
    $pageaddr = escape(index_url($_SERVER));
    echo '<?xml version="1.0" encoding="UTF-8"?><rss version="2.0">';
    echo '<channel>';
    echo '<title>Daily - '. $conf->get('general.title') . '</title>';
    echo '<link>'. $pageaddr .'</link>';
    echo '<description>Daily shared links</description>';
    echo '<language>en-en</language>';
    echo '<copyright>'. $pageaddr .'</copyright>'. PHP_EOL;

    // For each day.
    foreach ($days as $day => $linkdates) {
        $dayDate = DateTime::createFromFormat(LinkDB::LINK_DATE_FORMAT, $day.'_000000');
        $absurl = escape(index_url($_SERVER).'?do=daily&day='.$day);  // Absolute URL of the corresponding "Daily" page.

        // Build the HTML body of this RSS entry.
        $html = '';
        $href = '';
        $links = array();

        // We pre-format some fields for proper output.
        foreach ($linkdates as $linkdate) {
            $l = $LINKSDB[$linkdate];
            $l['formatedDescription'] = format_description($l['description'], $conf->get('redirector.url'));
            $l['thumbnail'] = thumbnail($conf, $l['url']);
            $l_date = DateTime::createFromFormat(LinkDB::LINK_DATE_FORMAT, $l['linkdate']);
            $l['timestamp'] = $l_date->getTimestamp();
            if (startsWith($l['url'], '?')) {
                $l['url'] = index_url($_SERVER) . $l['url'];  // make permalink URL absolute
            }
            $links[$linkdate] = $l;
        }

        // Then build the HTML for this day:
        $tpl = new RainTPL;
        $tpl->assign('title', $conf->get('general.title'));
        $tpl->assign('daydate', $dayDate->getTimestamp());
        $tpl->assign('absurl', $absurl);
        $tpl->assign('links', $links);
        $tpl->assign('rssdate', escape($dayDate->format(DateTime::RSS)));
        $tpl->assign('hide_timestamps', $conf->get('privacy.hide_timestamps', false));
        $html = $tpl->draw('dailyrss', $return_string=true);

        echo $html . PHP_EOL;
    }
    echo '</channel></rss><!-- Cached version of '. escape(page_url($_SERVER)) .' -->';

    $cache->cache(ob_get_contents());
    ob_end_flush();
    exit;
}

/**
 * Show the 'Daily' page.
 *
 * @param PageBuilder   $pageBuilder   Template engine wrapper.
 * @param LinkDB        $LINKSDB       LinkDB instance.
 * @param ConfigManager $conf          Configuration Manager instance.
 * @param PluginManager $pluginManager Plugin Manager instane.
 */
function showDaily($pageBuilder, $LINKSDB, $conf, $pluginManager)
{
    $day=date('Ymd',strtotime('-1 day')); // Yesterday, in format YYYYMMDD.
    if (isset($_GET['day'])) $day=$_GET['day'];

    $days = $LINKSDB->days();
    $i = array_search($day,$days);
    if ($i===false) { $i=count($days)-1; $day=$days[$i]; }
    $previousday='';
    $nextday='';
    if ($i!==false)
    {
        if ($i>=1) $previousday=$days[$i-1];
        if ($i<count($days)-1) $nextday=$days[$i+1];
    }

    try {
        $linksToDisplay = $LINKSDB->filterDay($day);
    } catch (Exception $exc) {
        error_log($exc);
        $linksToDisplay = array();
    }

    // We pre-format some fields for proper output.
    foreach($linksToDisplay as $key=>$link)
    {

        $taglist = explode(' ',$link['tags']);
        uasort($taglist, 'strcasecmp');
        $linksToDisplay[$key]['taglist']=$taglist;
        $linksToDisplay[$key]['formatedDescription'] = format_description($link['description'], $conf->get('redirector.url'));
        $linksToDisplay[$key]['thumbnail'] = thumbnail($conf, $link['url']);
        $date = DateTime::createFromFormat(LinkDB::LINK_DATE_FORMAT, $link['linkdate']);
        $linksToDisplay[$key]['timestamp'] = $date->getTimestamp();
    }

    /* We need to spread the articles on 3 columns.
       I did not want to use a JavaScript lib like http://masonry.desandro.com/
       so I manually spread entries with a simple method: I roughly evaluate the
       height of a div according to title and description length.
    */
    $columns=array(array(),array(),array()); // Entries to display, for each column.
    $fill=array(0,0,0);  // Rough estimate of columns fill.
    foreach($linksToDisplay as $key=>$link)
    {
        // Roughly estimate length of entry (by counting characters)
        // Title: 30 chars = 1 line. 1 line is 30 pixels height.
        // Description: 836 characters gives roughly 342 pixel height.
        // This is not perfect, but it's usually OK.
        $length=strlen($link['title'])+(342*strlen($link['description']))/836;
        if ($link['thumbnail']) $length +=100; // 1 thumbnails roughly takes 100 pixels height.
        // Then put in column which is the less filled:
        $smallest=min($fill); // find smallest value in array.
        $index=array_search($smallest,$fill); // find index of this smallest value.
        array_push($columns[$index],$link); // Put entry in this column.
        $fill[$index]+=$length;
    }

    $dayDate = DateTime::createFromFormat(LinkDB::LINK_DATE_FORMAT, $day.'_000000');
    $data = array(
        'linksToDisplay' => $linksToDisplay,
        'cols' => $columns,
        'day' => $dayDate->getTimestamp(),
        'previousday' => $previousday,
        'nextday' => $nextday,
    );

    $pluginManager->executeHooks('render_daily', $data, array('loggedin' => isLoggedIn()));

    foreach ($data as $key => $value) {
        $pageBuilder->assign($key, $value);
    }

    $pageBuilder->renderPage('daily');
    exit;
}

/**
 * Renders the linklist
 *
 * @param pageBuilder   $PAGE    pageBuilder instance.
 * @param LinkDB        $LINKSDB LinkDB instance.
 * @param ConfigManager $conf    Configuration Manager instance.
 * @param PluginManager $pluginManager Plugin Manager instance.
 */
function showLinkList($PAGE, $LINKSDB, $conf, $pluginManager) {
    buildLinkList($PAGE,$LINKSDB, $conf, $pluginManager); // Compute list of links to display
    $PAGE->renderPage('linklist');
}

/**
 * Render HTML page (according to URL parameters and user rights)
 *
 * @param ConfigManager $conf          Configuration Manager instance.
 * @param PluginManager $pluginManager Plugin Manager instance,
 */
function renderPage($conf, $pluginManager)
{
    $LINKSDB = new LinkDB(
        $conf->get('resource.datastore'),
        isLoggedIn(),
        $conf->get('privacy.hide_public_links'),
        $conf->get('redirector.url'),
        $conf->get('redirector.encode_url')
    );

    $updater = new Updater(
        read_updates_file($conf->get('resource.updates')),
        $LINKSDB,
        $conf,
        isLoggedIn()
    );
    try {
        $newUpdates = $updater->update();
        if (! empty($newUpdates)) {
            write_updates_file(
                $conf->get('resource.updates'),
                $updater->getDoneUpdates()
            );
        }
    }
    catch(Exception $e) {
        die($e->getMessage());
    }

    $PAGE = new PageBuilder($conf);
    $PAGE->assign('linkcount', count($LINKSDB));
    $PAGE->assign('privateLinkcount', count_private($LINKSDB));

    // Determine which page will be rendered.
    $query = (isset($_SERVER['QUERY_STRING'])) ? $_SERVER['QUERY_STRING'] : '';
    $targetPage = Router::findPage($query, $_GET, isLoggedIn());

    // Call plugin hooks for header, footer and includes, specifying which page will be rendered.
    // Then assign generated data to RainTPL.
    $common_hooks = array(
        'includes',
        'header',
        'footer',
    );

    foreach($common_hooks as $name) {
        $plugin_data = array();
        $pluginManager->executeHooks('render_' . $name, $plugin_data,
            array(
                'target' => $targetPage,
                'loggedin' => isLoggedIn()
            )
        );
        $PAGE->assign('plugins_' . $name, $plugin_data);
    }

    // -------- Display login form.
    if ($targetPage == Router::$PAGE_LOGIN)
    {
        if ($conf->get('security.open_shaarli')) { header('Location: ?'); exit; }  // No need to login for open Shaarli
        $token=''; if (ban_canLogin($conf)) $token=getToken($conf); // Do not waste token generation if not useful.
        $PAGE->assign('token',$token);
        if (isset($_GET['username'])) {
            $PAGE->assign('username', escape($_GET['username']));
        }
        $PAGE->assign('returnurl',(isset($_SERVER['HTTP_REFERER']) ? escape($_SERVER['HTTP_REFERER']):''));
        $PAGE->renderPage('loginform');
        exit;
    }
    // -------- User wants to logout.
    if (isset($_SERVER['QUERY_STRING']) && startsWith($_SERVER['QUERY_STRING'], 'do=logout'))
    {
        invalidateCaches($conf->get('resource.page_cache'));
        logout();
        header('Location: ?');
        exit;
    }

    // -------- Picture wall
    if ($targetPage == Router::$PAGE_PICWALL)
    {
        // Optionally filter the results:
        $links = $LINKSDB->filterSearch($_GET);
        $linksToDisplay = array();

        // Get only links which have a thumbnail.
        foreach($links as $link)
        {
            $permalink='?'.escape(smallhash($link['linkdate']));
            $thumb=lazyThumbnail($conf, $link['url'],$permalink);
            if ($thumb!='') // Only output links which have a thumbnail.
            {
                $link['thumbnail']=$thumb; // Thumbnail HTML code.
                $linksToDisplay[]=$link; // Add to array.
            }
        }

        $data = array(
            'linksToDisplay' => $linksToDisplay,
        );
        $pluginManager->executeHooks('render_picwall', $data, array('loggedin' => isLoggedIn()));

        foreach ($data as $key => $value) {
            $PAGE->assign($key, $value);
        }

        $PAGE->renderPage('picwall');
        exit;
    }

    // -------- Tag cloud
    if ($targetPage == Router::$PAGE_TAGCLOUD)
    {
        $tags= $LINKSDB->allTags();

        // We sort tags alphabetically, then choose a font size according to count.
        // First, find max value.
        $maxcount = 0;
        foreach ($tags as $value) {
            $maxcount = max($maxcount, $value);
        }

        // Sort tags alphabetically: case insensitive, support locale if avalaible.
        uksort($tags, function($a, $b) {
            // Collator is part of PHP intl.
            if (class_exists('Collator')) {
                $c = new Collator(setlocale(LC_COLLATE, 0));
                if (!intl_is_failure(intl_get_error_code())) {
                    return $c->compare($a, $b);
                }
            }
            return strcasecmp($a, $b);
        });

        $tagList = array();
        foreach($tags as $key => $value) {
            // Tag font size scaling:
            //   default 15 and 30 logarithm bases affect scaling,
            //   22 and 6 are arbitrary font sizes for max and min sizes.
            $size = log($value, 15) / log($maxcount, 30) * 2.2 + 0.8;
            $tagList[$key] = array(
                'count' => $value,
                'size' => number_format($size, 2, '.', ''),
            );
        }

        $data = array(
            'tags' => $tagList,
        );
        $pluginManager->executeHooks('render_tagcloud', $data, array('loggedin' => isLoggedIn()));

        foreach ($data as $key => $value) {
            $PAGE->assign($key, $value);
        }

        $PAGE->renderPage('tagcloud');
        exit;
    }

    // Daily page.
    if ($targetPage == Router::$PAGE_DAILY) {
        showDaily($PAGE, $LINKSDB, $conf, $pluginManager);
    }

    // ATOM and RSS feed.
    if ($targetPage == Router::$PAGE_FEED_ATOM || $targetPage == Router::$PAGE_FEED_RSS) {
        $feedType = $targetPage == Router::$PAGE_FEED_RSS ? FeedBuilder::$FEED_RSS : FeedBuilder::$FEED_ATOM;
        header('Content-Type: application/'. $feedType .'+xml; charset=utf-8');

        // Cache system
        $query = $_SERVER['QUERY_STRING'];
        $cache = new CachedPage(
            $conf->get('resource.page_cache'),
            page_url($_SERVER),
            startsWith($query,'do='. $targetPage) && !isLoggedIn()
        );
        $cached = $cache->cachedVersion();
        if (!empty($cached)) {
            echo $cached;
            exit;
        }

        // Generate data.
        $feedGenerator = new FeedBuilder($LINKSDB, $feedType, $_SERVER, $_GET, isLoggedIn());
        $feedGenerator->setLocale(strtolower(setlocale(LC_COLLATE, 0)));
        $feedGenerator->setHideDates($conf->get('privacy.hide_timestamps') && !isLoggedIn());
        $feedGenerator->setUsePermalinks(isset($_GET['permalinks']) || !$conf->get('feed.rss_permalinks'));
        $pshUrl = $conf->get('config.PUBSUBHUB_URL');
        if (!empty($pshUrl)) {
            $feedGenerator->setPubsubhubUrl($pshUrl);
        }
        $data = $feedGenerator->buildData();

        // Process plugin hook.
        $pluginManager->executeHooks('render_feed', $data, array(
            'loggedin' => isLoggedIn(),
            'target' => $targetPage,
        ));

        // Render the template.
        $PAGE->assignAll($data);
        $PAGE->renderPage('feed.'. $feedType);
        $cache->cache(ob_get_contents());
        ob_end_flush();
        exit;
    }

    // Display openseach plugin (XML)
    if ($targetPage == Router::$PAGE_OPENSEARCH) {
        header('Content-Type: application/xml; charset=utf-8');
        $PAGE->assign('serverurl', index_url($_SERVER));
        $PAGE->renderPage('opensearch');
        exit;
    }

    // -------- User clicks on a tag in a link: The tag is added to the list of searched tags (searchtags=...)
    if (isset($_GET['addtag']))
    {
        // Get previous URL (http_referer) and add the tag to the searchtags parameters in query.
        if (empty($_SERVER['HTTP_REFERER'])) { header('Location: ?searchtags='.urlencode($_GET['addtag'])); exit; } // In case browser does not send HTTP_REFERER
        parse_str(parse_url($_SERVER['HTTP_REFERER'],PHP_URL_QUERY), $params);

        // Prevent redirection loop
        if (isset($params['addtag'])) {
            unset($params['addtag']);
        }

        // Check if this tag is already in the search query and ignore it if it is.
        // Each tag is always separated by a space
        if (isset($params['searchtags'])) {
            $current_tags = explode(' ', $params['searchtags']);
        } else {
            $current_tags = array();
        }
        $addtag = true;
        foreach ($current_tags as $value) {
            if ($value === $_GET['addtag']) {
                $addtag = false;
                break;
            }
        }
        // Append the tag if necessary
        if (empty($params['searchtags'])) {
            $params['searchtags'] = trim($_GET['addtag']);
        }
        else if ($addtag) {
            $params['searchtags'] = trim($params['searchtags']).' '.trim($_GET['addtag']);
        }

        unset($params['page']); // We also remove page (keeping the same page has no sense, since the results are different)
        header('Location: ?'.http_build_query($params));
        exit;
    }

    // -------- User clicks on a tag in result count: Remove the tag from the list of searched tags (searchtags=...)
    if (isset($_GET['removetag'])) {
        // Get previous URL (http_referer) and remove the tag from the searchtags parameters in query.
        if (empty($_SERVER['HTTP_REFERER'])) {
            header('Location: ?');
            exit;
        }

        // In case browser does not send HTTP_REFERER
        parse_str(parse_url($_SERVER['HTTP_REFERER'], PHP_URL_QUERY), $params);

        // Prevent redirection loop
        if (isset($params['removetag'])) {
            unset($params['removetag']);
        }

        if (isset($params['searchtags'])) {
            $tags = explode(' ', $params['searchtags']);
            // Remove value from array $tags.
            $tags = array_diff($tags, array($_GET['removetag']));
            $params['searchtags'] = implode(' ',$tags);

            if (empty($params['searchtags'])) {
                unset($params['searchtags']);
            }

            unset($params['page']); // We also remove page (keeping the same page has no sense, since the results are different)
        }
        header('Location: ?'.http_build_query($params));
        exit;
    }

    // -------- User wants to change the number of links per page (linksperpage=...)
    if (isset($_GET['linksperpage'])) {
        if (is_numeric($_GET['linksperpage'])) {
            $_SESSION['LINKS_PER_PAGE']=abs(intval($_GET['linksperpage']));
        }

        header('Location: '. generateLocation($_SERVER['HTTP_REFERER'], $_SERVER['HTTP_HOST'], array('linksperpage')));
        exit;
    }

    // -------- User wants to see only private links (toggle)
    if (isset($_GET['privateonly'])) {
        if (empty($_SESSION['privateonly'])) {
            $_SESSION['privateonly'] = 1; // See only private links
        } else {
            unset($_SESSION['privateonly']); // See all links
        }

        header('Location: '. generateLocation($_SERVER['HTTP_REFERER'], $_SERVER['HTTP_HOST'], array('privateonly')));
        exit;
    }

    // -------- Handle other actions allowed for non-logged in users:
    if (!isLoggedIn())
    {
        // User tries to post new link but is not logged in:
        // Show login screen, then redirect to ?post=...
        if (isset($_GET['post']))
        {
            header('Location: ?do=login&post='.urlencode($_GET['post']).(!empty($_GET['title'])?'&title='.urlencode($_GET['title']):'').(!empty($_GET['description'])?'&description='.urlencode($_GET['description']):'').(!empty($_GET['source'])?'&source='.urlencode($_GET['source']):'')); // Redirect to login page, then back to post link.
            exit;
        }

        showLinkList($PAGE, $LINKSDB, $conf, $pluginManager);
        if (isset($_GET['edit_link'])) {
            header('Location: ?do=login&edit_link='. escape($_GET['edit_link']));
            exit;
        }

        exit; // Never remove this one! All operations below are reserved for logged in user.
    }

    // -------- All other functions are reserved for the registered user:

    // -------- Display the Tools menu if requested (import/export/bookmarklet...)
    if ($targetPage == Router::$PAGE_TOOLS)
    {
        $data = array(
            'pageabsaddr' => index_url($_SERVER),
        );
        $pluginManager->executeHooks('render_tools', $data);

        foreach ($data as $key => $value) {
            $PAGE->assign($key, $value);
        }

        $PAGE->renderPage('tools');
        exit;
    }

    // -------- User wants to change his/her password.
    if ($targetPage == Router::$PAGE_CHANGEPASSWORD)
    {
        if ($conf->get('security.open_shaarli')) {
            die('You are not supposed to change a password on an Open Shaarli.');
        }

        if (!empty($_POST['setpassword']) && !empty($_POST['oldpassword']))
        {
            if (!tokenOk($_POST['token'])) die('Wrong token.'); // Go away!

            // Make sure old password is correct.
            $oldhash = sha1($_POST['oldpassword'].$conf->get('credentials.login').$conf->get('credentials.salt'));
            if ($oldhash!= $conf->get('credentials.hash')) { echo '<script>alert("The old password is not correct.");document.location=\'?do=changepasswd\';</script>'; exit; }
            // Save new password
            // Salt renders rainbow-tables attacks useless.
            $conf->set('credentials.salt', sha1(uniqid('', true) .'_'. mt_rand()));
            $conf->set('credentials.hash', sha1($_POST['setpassword'] . $conf->get('credentials.login') . $conf->get('credentials.salt')));
            try {
                $conf->write(isLoggedIn());
            }
            catch(Exception $e) {
                error_log(
                    'ERROR while writing config file after changing password.' . PHP_EOL .
                    $e->getMessage()
                );

                // TODO: do not handle exceptions/errors in JS.
                echo '<script>alert("'. $e->getMessage() .'");document.location=\'?do=tools\';</script>';
                exit;
            }
            echo '<script>alert("Your password has been changed.");document.location=\'?do=tools\';</script>';
            exit;
        }
        else // show the change password form.
        {
            $PAGE->assign('token',getToken($conf));
            $PAGE->renderPage('changepassword');
            exit;
        }
    }

    // -------- User wants to change configuration
    if ($targetPage == Router::$PAGE_CONFIGURE)
    {
        if (!empty($_POST['title']) )
        {
            if (!tokenOk($_POST['token'])) {
                die('Wrong token.'); // Go away!
            }
            $tz = 'UTC';
            if (!empty($_POST['continent']) && !empty($_POST['city'])
                && isTimeZoneValid($_POST['continent'], $_POST['city'])
            ) {
                $tz = $_POST['continent'] . '/' . $_POST['city'];
            }
            $conf->set('general.timezone', $tz);
            $conf->set('general.title', escape($_POST['title']));
            $conf->set('general.header_link', escape($_POST['titleLink']));
            $conf->set('redirector.url', escape($_POST['redirector']));
            $conf->set('security.session_protection_disabled', !empty($_POST['disablesessionprotection']));
            $conf->set('privacy.default_private_links', !empty($_POST['privateLinkByDefault']));
            $conf->set('feed.rss_permalinks', !empty($_POST['enableRssPermalinks']));
            $conf->set('updates.check_updates', !empty($_POST['updateCheck']));
            $conf->set('privacy.hide_public_links', !empty($_POST['hidePublicLinks']));
            try {
                $conf->write(isLoggedIn());
            }
            catch(Exception $e) {
                error_log(
                    'ERROR while writing config file after configuration update.' . PHP_EOL .
                    $e->getMessage()
                );

                // TODO: do not handle exceptions/errors in JS.
                echo '<script>alert("'. $e->getMessage() .'");document.location=\'?do=configure\';</script>';
                exit;
            }
            echo '<script>alert("Configuration was saved.");document.location=\'?do=configure\';</script>';
            exit;
        }
        else // Show the configuration form.
        {
            $PAGE->assign('token',getToken($conf));
            $PAGE->assign('title', $conf->get('general.title'));
            $PAGE->assign('redirector', $conf->get('redirector.url'));
            list($timezone_form, $timezone_js) = generateTimeZoneForm($conf->get('general.timezone'));
            $PAGE->assign('timezone_form', $timezone_form);
            $PAGE->assign('timezone_js',$timezone_js);
            $PAGE->assign('private_links_default', $conf->get('privacy.default_private_links', false));
            $PAGE->assign('session_protection_disabled', $conf->get('security.session_protection_disabled', false));
            $PAGE->assign('enable_rss_permalinks', $conf->get('feed.rss_permalinks', false));
            $PAGE->assign('enable_update_check', $conf->get('updates.check_updates', true));
            $PAGE->assign('hide_public_links', $conf->get('privacy.hide_public_links', false));
            $PAGE->renderPage('configure');
            exit;
        }
    }

    // -------- User wants to rename a tag or delete it
    if ($targetPage == Router::$PAGE_CHANGETAG)
    {
        if (empty($_POST['fromtag']) || (empty($_POST['totag']) && isset($_POST['renametag']))) {
            $PAGE->assign('token', getToken($conf));
            $PAGE->assign('tags', $LINKSDB->allTags());
            $PAGE->renderPage('changetag');
            exit;
        }

        if (!tokenOk($_POST['token'])) {
            die('Wrong token.');
        }

        // Delete a tag:
        if (isset($_POST['deletetag']) && !empty($_POST['fromtag'])) {
            $needle = trim($_POST['fromtag']);
            // True for case-sensitive tag search.
            $linksToAlter = $LINKSDB->filterSearch(array('searchtags' => $needle), true);
            foreach($linksToAlter as $key=>$value)
            {
                $tags = explode(' ',trim($value['tags']));
                unset($tags[array_search($needle,$tags)]); // Remove tag.
                $value['tags']=trim(implode(' ',$tags));
                $LINKSDB[$key]=$value;
            }
            $LINKSDB->savedb($conf->get('resource.page_cache'));
            echo '<script>alert("Tag was removed from '.count($linksToAlter).' links.");document.location=\'?\';</script>';
            exit;
        }

        // Rename a tag:
        if (isset($_POST['renametag']) && !empty($_POST['fromtag']) && !empty($_POST['totag'])) {
            $needle = trim($_POST['fromtag']);
            // True for case-sensitive tag search.
            $linksToAlter = $LINKSDB->filterSearch(array('searchtags' => $needle), true);
            foreach($linksToAlter as $key=>$value)
            {
                $tags = explode(' ',trim($value['tags']));
                $tags[array_search($needle,$tags)] = trim($_POST['totag']); // Replace tags value.
                $value['tags']=trim(implode(' ',$tags));
                $LINKSDB[$key]=$value;
            }
            $LINKSDB->savedb($conf->get('resource.page_cache')); // Save to disk.
            echo '<script>alert("Tag was renamed in '.count($linksToAlter).' links.");document.location=\'?searchtags='.urlencode($_POST['totag']).'\';</script>';
            exit;
        }
    }

    // -------- User wants to add a link without using the bookmarklet: Show form.
    if ($targetPage == Router::$PAGE_ADDLINK)
    {
        $PAGE->renderPage('addlink');
        exit;
    }

    // -------- User clicked the "Save" button when editing a link: Save link to database.
    if (isset($_POST['save_edit']))
    {
        // Go away!
        if (! tokenOk($_POST['token'])) {
            die('Wrong token.');
        }
        // Remove multiple spaces.
        $tags = trim(preg_replace('/\s\s+/', ' ', $_POST['lf_tags']));
        // Remove first '-' char in tags.
        $tags = preg_replace('/(^| )\-/', '$1', $tags);
        // Remove duplicates.
        $tags = implode(' ', array_unique(explode(' ', $tags)));
        $linkdate = $_POST['lf_linkdate'];
        $url = trim($_POST['lf_url']);
        if (! startsWith($url, 'http:') && ! startsWith($url, 'https:')
            && ! startsWith($url, 'ftp:') && ! startsWith($url, 'magnet:')
            && ! startsWith($url, '?') && ! startsWith($url, 'javascript:')
        ) {
            $url = 'http://' . $url;
        }

        $link = array(
            'title' => trim($_POST['lf_title']),
            'url' => $url,
            'description' => $_POST['lf_description'],
            'private' => (isset($_POST['lf_private']) ? 1 : 0),
            'linkdate' => $linkdate,
            'tags' => str_replace(',', ' ', $tags)
        );
        // If title is empty, use the URL as title.
        if ($link['title'] == '') {
            $link['title'] = $link['url'];
        }

        $pluginManager->executeHooks('save_link', $link);

        $LINKSDB[$linkdate] = $link;
        $LINKSDB->savedb($conf->get('resource.page_cache'));
        pubsubhub($conf);

        // If we are called from the bookmarklet, we must close the popup:
        if (isset($_GET['source']) && ($_GET['source']=='bookmarklet' || $_GET['source']=='firefoxsocialapi')) {
            echo '<script>self.close();</script>';
            exit;
        }

        $returnurl = !empty($_POST['returnurl']) ? $_POST['returnurl'] : '?';
        $location = generateLocation($returnurl, $_SERVER['HTTP_HOST'], array('addlink', 'post', 'edit_link'));
        // Scroll to the link which has been edited.
        $location .= '#' . smallHash($_POST['lf_linkdate']);
        // After saving the link, redirect to the page the user was on.
        header('Location: '. $location);
        exit;
    }

    // -------- User clicked the "Cancel" button when editing a link.
    if (isset($_POST['cancel_edit']))
    {
        // If we are called from the bookmarklet, we must close the popup:
        if (isset($_GET['source']) && ($_GET['source']=='bookmarklet' || $_GET['source']=='firefoxsocialapi')) { echo '<script>self.close();</script>'; exit; }
        $returnurl = ( isset($_POST['returnurl']) ? $_POST['returnurl'] : '?' );
        $returnurl .= '#'.smallHash($_POST['lf_linkdate']);  // Scroll to the link which has been edited.
        $returnurl = generateLocation($returnurl, $_SERVER['HTTP_HOST'], array('addlink', 'post', 'edit_link'));
        header('Location: '.$returnurl); // After canceling, redirect to the page the user was on.
        exit;
    }

    // -------- User clicked the "Delete" button when editing a link: Delete link from database.
    if (isset($_POST['delete_link']))
    {
        if (!tokenOk($_POST['token'])) die('Wrong token.');
        // We do not need to ask for confirmation:
        // - confirmation is handled by JavaScript
        // - we are protected from XSRF by the token.
        $linkdate=$_POST['lf_linkdate'];

        $pluginManager->executeHooks('delete_link', $LINKSDB[$linkdate]);

        unset($LINKSDB[$linkdate]);
        $LINKSDB->savedb('resource.page_cache'); // save to disk

        // If we are called from the bookmarklet, we must close the popup:
        if (isset($_GET['source']) && ($_GET['source']=='bookmarklet' || $_GET['source']=='firefoxsocialapi')) { echo '<script>self.close();</script>'; exit; }
        // Pick where we're going to redirect
        // =============================================================
        // Basically, we can't redirect to where we were previously if it was a permalink
        // or an edit_link, because it would 404.
        // Cases:
        //    - /             : nothing in $_GET, redirect to self
        //    - /?page        : redirect to self
        //    - /?searchterm  : redirect to self (there might be other links)
        //    - /?searchtags  : redirect to self
        //    - /permalink    : redirect to / (the link does not exist anymore)
        //    - /?edit_link   : redirect to / (the link does not exist anymore)
        // PHP treats the permalink as a $_GET variable, so we need to check if every condition for self
        // redirect is not satisfied, and only then redirect to /
        $location = "?";
        // Self redirection
        if (count($_GET) == 0
            || isset($_GET['page'])
            || isset($_GET['searchterm'])
            || isset($_GET['searchtags'])
        ) {
            if (isset($_POST['returnurl'])) {
                $location = $_POST['returnurl']; // Handle redirects given by the form
            } else {
                $location = generateLocation($_SERVER['HTTP_REFERER'], $_SERVER['HTTP_HOST'], array('delete_link'));
            }
        }

        header('Location: ' . $location); // After deleting the link, redirect to appropriate location
        exit;
    }

    // -------- User clicked the "EDIT" button on a link: Display link edit form.
    if (isset($_GET['edit_link']))
    {
        $link = $LINKSDB[$_GET['edit_link']];  // Read database
        if (!$link) { header('Location: ?'); exit; } // Link not found in database.
        $data = array(
            'link' => $link,
            'link_is_new' => false,
            'token' => getToken($conf),
            'http_referer' => (isset($_SERVER['HTTP_REFERER']) ? escape($_SERVER['HTTP_REFERER']) : ''),
            'tags' => $LINKSDB->allTags(),
        );
        $pluginManager->executeHooks('render_editlink', $data);

        foreach ($data as $key => $value) {
            $PAGE->assign($key, $value);
        }

        $PAGE->renderPage('editlink');
        exit;
    }

    // -------- User want to post a new link: Display link edit form.
    if (isset($_GET['post'])) {
        $url = cleanup_url($_GET['post']);

        $link_is_new = false;
        // Check if URL is not already in database (in this case, we will edit the existing link)
        $link = $LINKSDB->getLinkFromUrl($url);
        if (!$link)
        {
            $link_is_new = true;
            $linkdate = strval(date('Ymd_His'));
            // Get title if it was provided in URL (by the bookmarklet).
            $title = empty($_GET['title']) ? '' : escape($_GET['title']);
            // Get description if it was provided in URL (by the bookmarklet). [Bronco added that]
            $description = empty($_GET['description']) ? '' : escape($_GET['description']);
            $tags = empty($_GET['tags']) ? '' : escape($_GET['tags']);
            $private = !empty($_GET['private']) && $_GET['private'] === "1" ? 1 : 0;
            // If this is an HTTP(S) link, we try go get the page to extract the title (otherwise we will to straight to the edit form.)
            if (empty($title) && strpos(get_url_scheme($url), 'http') !== false) {
                // Short timeout to keep the application responsive
                list($headers, $content) = get_http_response($url, 4);
                if (strpos($headers[0], '200 OK') !== false) {
                    // Retrieve charset.
                    $charset = get_charset($headers, $content);
                    // Extract title.
                    $title = html_extract_title($content);
                    // Re-encode title in utf-8 if necessary.
                    if (! empty($title) && strtolower($charset) != 'utf-8') {
                        $title = mb_convert_encoding($title, 'utf-8', $charset);
                    }
                }
            }

            if ($url == '') {
                $url = '?' . smallHash($linkdate);
                $title = 'Note: ';
            }
            $url = escape($url);
            $title = escape($title);

            $link = array(
                'linkdate' => $linkdate,
                'title' => $title,
                'url' => $url,
                'description' => $description,
                'tags' => $tags,
                'private' => $private
            );
        }

        $data = array(
            'link' => $link,
            'link_is_new' => $link_is_new,
            'token' => getToken($conf), // XSRF protection.
            'http_referer' => (isset($_SERVER['HTTP_REFERER']) ? escape($_SERVER['HTTP_REFERER']) : ''),
            'source' => (isset($_GET['source']) ? $_GET['source'] : ''),
            'tags' => $LINKSDB->allTags(),
            'default_private_links' => $conf->get('default_private_links', false),
        );
        $pluginManager->executeHooks('render_editlink', $data);

        foreach ($data as $key => $value) {
            $PAGE->assign($key, $value);
        }

        $PAGE->renderPage('editlink');
        exit;
    }

    if ($targetPage == Router::$PAGE_EXPORT) {
        // Export links as a Netscape Bookmarks file

        if (empty($_GET['selection'])) {
            $PAGE->renderPage('export');
            exit;
        }

        // export as bookmarks_(all|private|public)_YYYYmmdd_HHMMSS.html
        $selection = $_GET['selection'];
        if (isset($_GET['prepend_note_url'])) {
            $prependNoteUrl = $_GET['prepend_note_url'];
        } else {
            $prependNoteUrl = false;
        }

        try {
            $PAGE->assign(
                'links',
                NetscapeBookmarkUtils::filterAndFormat(
                    $LINKSDB,
                    $selection,
                    $prependNoteUrl,
                    index_url($_SERVER)
                )
            );
        } catch (Exception $exc) {
            header('Content-Type: text/plain; charset=utf-8');
            echo $exc->getMessage();
            exit;
        }
        $now = new DateTime();
        header('Content-Type: text/html; charset=utf-8');
        header(
            'Content-disposition: attachment; filename=bookmarks_'
           .$selection.'_'.$now->format(LinkDB::LINK_DATE_FORMAT).'.html'
        );
        $PAGE->assign('date', $now->format(DateTime::RFC822));
        $PAGE->assign('eol', PHP_EOL);
        $PAGE->assign('selection', $selection);
        $PAGE->renderPage('export.bookmarks');
        exit;
    }

    // -------- User is uploading a file for import
    if (isset($_SERVER['QUERY_STRING']) && startsWith($_SERVER['QUERY_STRING'], 'do=upload'))
    {
        // If file is too big, some form field may be missing.
        if (!isset($_POST['token']) || (!isset($_FILES)) || (isset($_FILES['filetoupload']['size']) && $_FILES['filetoupload']['size']==0))
        {
            $returnurl = ( empty($_SERVER['HTTP_REFERER']) ? '?' : $_SERVER['HTTP_REFERER'] );
            echo '<script>alert("The file you are trying to upload is probably bigger than what this webserver can accept ('.getMaxFileSize().' bytes). Please upload in smaller chunks.");document.location=\''.escape($returnurl).'\';</script>';
            exit;
        }
        if (!tokenOk($_POST['token'])) die('Wrong token.');
        importFile($LINKSDB);
        exit;
    }

    // -------- Show upload/import dialog:
    if ($targetPage == Router::$PAGE_IMPORT)
    {
        $PAGE->assign('token',getToken($conf));
        $PAGE->assign('maxfilesize',getMaxFileSize());
        $PAGE->renderPage('import');
        exit;
    }

    // Plugin administration page
    if ($targetPage == Router::$PAGE_PLUGINSADMIN) {
        $pluginMeta = $pluginManager->getPluginsMeta();

        // Split plugins into 2 arrays: ordered enabled plugins and disabled.
        $enabledPlugins = array_filter($pluginMeta, function($v) { return $v['order'] !== false; });
        // Load parameters.
        $enabledPlugins = load_plugin_parameter_values($enabledPlugins, $conf->get('plugins', array()));
        uasort(
            $enabledPlugins,
            function($a, $b) { return $a['order'] - $b['order']; }
        );
        $disabledPlugins = array_filter($pluginMeta, function($v) { return $v['order'] === false; });

        $PAGE->assign('enabledPlugins', $enabledPlugins);
        $PAGE->assign('disabledPlugins', $disabledPlugins);
        $PAGE->renderPage('pluginsadmin');
        exit;
    }

    // Plugin administration form action
    if ($targetPage == Router::$PAGE_SAVE_PLUGINSADMIN) {
        try {
            if (isset($_POST['parameters_form'])) {
                unset($_POST['parameters_form']);
                foreach ($_POST as $param => $value) {
                    $conf->set('plugins.'. $param, escape($value));
                }
            }
            else {
                $conf->set('general.enabled_plugins', save_plugin_config($_POST));
            }
            $conf->write(isLoggedIn());
        }
        catch (Exception $e) {
            error_log(
                'ERROR while saving plugin configuration:.' . PHP_EOL .
                $e->getMessage()
            );

            // TODO: do not handle exceptions/errors in JS.
            echo '<script>alert("'. $e->getMessage() .'");document.location=\'?do='. Router::$PAGE_PLUGINSADMIN .'\';</script>';
            exit;
        }
        header('Location: ?do='. Router::$PAGE_PLUGINSADMIN);
        exit;
    }

    // -------- Otherwise, simply display search form and links:
    showLinkList($PAGE, $LINKSDB, $conf, $pluginManager);
    exit;
}

/**
 * Process the import file form.
 *
 * @param LinkDB        $LINKSDB Loaded LinkDB instance.
 * @param ConfigManager $conf    Configuration Manager instance.
 */
function importFile($LINKSDB, $conf)
{
    if (!isLoggedIn()) { die('Not allowed.'); }

    $filename=$_FILES['filetoupload']['name'];
    $filesize=$_FILES['filetoupload']['size'];
    $data=file_get_contents($_FILES['filetoupload']['tmp_name']);
    $private = (empty($_POST['private']) ? 0 : 1); // Should the links be imported as private?
    $overwrite = !empty($_POST['overwrite']) ; // Should the imported links overwrite existing ones?
    $import_count=0;

    // Sniff file type:
    $type='unknown';
    if (startsWith($data,'<!DOCTYPE NETSCAPE-Bookmark-file-1>')) $type='netscape'; // Netscape bookmark file (aka Firefox).

    // Then import the bookmarks.
    if ($type=='netscape')
    {
        // This is a standard Netscape-style bookmark file.
        // This format is supported by all browsers (except IE, of course), also Delicious, Diigo and others.
        foreach(explode('<DT>',$data) as $html) // explode is very fast
        {
            $link = array('linkdate'=>'','title'=>'','url'=>'','description'=>'','tags'=>'','private'=>0);
            $d = explode('<DD>',$html);
            if (startsWith($d[0], '<A '))
            {
                $link['description'] = (isset($d[1]) ? html_entity_decode(trim($d[1]),ENT_QUOTES,'UTF-8') : '');  // Get description (optional)
                preg_match('!<A .*?>(.*?)</A>!i',$d[0],$matches); $link['title'] = (isset($matches[1]) ? trim($matches[1]) : '');  // Get title
                $link['title'] = html_entity_decode($link['title'],ENT_QUOTES,'UTF-8');
                preg_match_all('! ([A-Z_]+)=\"(.*?)"!i',$html,$matches,PREG_SET_ORDER);  // Get all other attributes
                $raw_add_date=0;
                foreach($matches as $m)
                {
                    $attr=$m[1]; $value=$m[2];
                    if ($attr=='HREF') $link['url']=html_entity_decode($value,ENT_QUOTES,'UTF-8');
                    elseif ($attr=='ADD_DATE')
                    {
                        $raw_add_date=intval($value);
                        if ($raw_add_date>30000000000) $raw_add_date/=1000;	//If larger than year 2920, then was likely stored in milliseconds instead of seconds
                    }
                    elseif ($attr=='PRIVATE') $link['private']=($value=='0'?0:1);
                    elseif ($attr=='TAGS') $link['tags']=html_entity_decode(str_replace(',',' ',$value),ENT_QUOTES,'UTF-8');
                }
                if ($link['url']!='')
                {
                    if ($private==1) $link['private']=1;
                    $dblink = $LINKSDB->getLinkFromUrl($link['url']); // See if the link is already in database.
                    if ($dblink==false)
                    {  // Link not in database, let's import it...
                       if (empty($raw_add_date)) $raw_add_date=time(); // In case of shitty bookmark file with no ADD_DATE

                       // Make sure date/time is not already used by another link.
                       // (Some bookmark files have several different links with the same ADD_DATE)
                       // We increment date by 1 second until we find a date which is not used in DB.
                       // (so that links that have the same date/time are more or less kept grouped by date, but do not conflict.)
                       while (!empty($LINKSDB[date('Ymd_His',$raw_add_date)])) { $raw_add_date++; }// Yes, I know it's ugly.
                       $link['linkdate']=date('Ymd_His',$raw_add_date);
                       $LINKSDB[$link['linkdate']] = $link;
                       $import_count++;
                    }
                    else // Link already present in database.
                    {
                        if ($overwrite)
                        {   // If overwrite is required, we import link data, except date/time.
                            $link['linkdate']=$dblink['linkdate'];
                            $LINKSDB[$link['linkdate']] = $link;
                            $import_count++;
                        }
                    }

                }
            }
        }
        $LINKSDB->savedb($conf->get('resource.page_cache'));

        echo '<script>alert("File '.json_encode($filename).' ('.$filesize.' bytes) was successfully processed: '.$import_count.' links imported.");document.location=\'?\';</script>';
    }
    else
    {
        echo '<script>alert("File '.json_encode($filename).' ('.$filesize.' bytes) has an unknown file format. Nothing was imported.");document.location=\'?\';</script>';
    }
}

/**
 * Template for the list of links (<div id="linklist">)
 * This function fills all the necessary fields in the $PAGE for the template 'linklist.html'
 *
 * @param pageBuilder   $PAGE          pageBuilder instance.
 * @param LinkDB        $LINKSDB       LinkDB instance.
 * @param ConfigManager $conf          Configuration Manager instance.
 * @param PluginManager $pluginManager Plugin Manager instance.
 */
function buildLinkList($PAGE,$LINKSDB, $conf, $pluginManager)
{
    // Used in templates
    $searchtags = !empty($_GET['searchtags']) ? escape($_GET['searchtags']) : '';
    $searchterm = !empty($_GET['searchterm']) ? escape($_GET['searchterm']) : '';

    // Smallhash filter
    if (! empty($_SERVER['QUERY_STRING'])
        && preg_match('/^[a-zA-Z0-9-_@]{6}($|&|#)/', $_SERVER['QUERY_STRING'])) {
        try {
            $linksToDisplay = $LINKSDB->filterHash($_SERVER['QUERY_STRING']);
        } catch (LinkNotFoundException $e) {
            $PAGE->render404($e->getMessage());
            exit;
        }
    } else {
        // Filter links according search parameters.
        $privateonly = !empty($_SESSION['privateonly']);
        $linksToDisplay = $LINKSDB->filterSearch($_GET, false, $privateonly);
    }

    // ---- Handle paging.
    $keys = array();
    foreach ($linksToDisplay as $key => $value) {
        $keys[] = $key;
    }



    // Select articles according to paging.
    $pagecount = ceil(count($keys) / $_SESSION['LINKS_PER_PAGE']);
    $pagecount = $pagecount == 0 ? 1 : $pagecount;
    $page= empty($_GET['page']) ? 1 : intval($_GET['page']);
    $page = $page < 1 ? 1 : $page;
    $page = $page > $pagecount ? $pagecount : $page;
    // Start index.
    $i = ($page-1) * $_SESSION['LINKS_PER_PAGE'];
    $end = $i + $_SESSION['LINKS_PER_PAGE'];
    $linkDisp = array();
    while ($i<$end && $i<count($keys))
    {
        $link = $linksToDisplay[$keys[$i]];
        $link['description'] = format_description($link['description'], $conf->get('redirector.url'));
        $classLi =  ($i % 2) != 0 ? '' : 'publicLinkHightLight';
        $link['class'] = $link['private'] == 0 ? $classLi : 'private';
        $date = DateTime::createFromFormat(LinkDB::LINK_DATE_FORMAT, $link['linkdate']);
        $link['timestamp'] = $date->getTimestamp();
        $taglist = explode(' ', $link['tags']);
        uasort($taglist, 'strcasecmp');
        $link['taglist'] = $taglist;
        $link['shorturl'] = smallHash($link['linkdate']);
        // Check for both signs of a note: starting with ? and 7 chars long.
        if ($link['url'][0] === '?' &&
            strlen($link['url']) === 7) {
            $link['url'] = index_url($_SERVER) . $link['url'];
        }

        $linkDisp[$keys[$i]] = $link;
        $i++;
    }

    // Compute paging navigation
    $searchtagsUrl = empty($searchtags) ? '' : '&searchtags=' . urlencode($searchtags);
    $searchtermUrl = empty($searchterm) ? '' : '&searchterm=' . urlencode($searchterm);
    $previous_page_url = '';
    if ($i != count($keys)) {
        $previous_page_url = '?page=' . ($page+1) . $searchtermUrl . $searchtagsUrl;
    }
    $next_page_url='';
    if ($page>1) {
        $next_page_url = '?page=' . ($page-1) . $searchtermUrl . $searchtagsUrl;
    }

    $token = isLoggedIn() ? getToken($conf) : '';

    // Fill all template fields.
    $data = array(
        'previous_page_url' => $previous_page_url,
        'next_page_url' => $next_page_url,
        'page_current' => $page,
        'page_max' => $pagecount,
        'result_count' => count($linksToDisplay),
        'search_term' => $searchterm,
        'search_tags' => $searchtags,
        'redirector' => $conf->get('redirector.url'),  // Optional redirector URL.
        'token' => $token,
        'links' => $linkDisp,
        'tags' => $LINKSDB->allTags(),
    );

    // If there is only a single link, we change on-the-fly the title of the page.
    if (count($linksToDisplay) == 1) {
        $data['pagetitle'] = $linksToDisplay[$keys[0]]['title'] .' - '. $conf->get('general.title');
    }

    $pluginManager->executeHooks('render_linklist', $data, array('loggedin' => isLoggedIn()));

    foreach ($data as $key => $value) {
        $PAGE->assign($key, $value);
    }

    return;
}

/**
 * Compute the thumbnail for a link.
 *
 * With a link to the original URL.
 * Understands various services (youtube.com...)
 * Input: $url = URL for which the thumbnail must be found.
 *        $href = if provided, this URL will be followed instead of $url
 * Returns an associative array with thumbnail attributes (src,href,width,height,style,alt)
 * Some of them may be missing.
 * Return an empty array if no thumbnail available.
 *
 * @param ConfigManager $conf Configuration Manager instance.
 * @param string        $url
 * @param string|bool   $href
 *
 * @return array
 */
function computeThumbnail($conf, $url, $href = false)
{
    if (!$conf->get('thumbnail.enable_thumbnails')) return array();
    if ($href==false) $href=$url;

    // For most hosts, the URL of the thumbnail can be easily deduced from the URL of the link.
    // (e.g. http://www.youtube.com/watch?v=spVypYk4kto --->  http://img.youtube.com/vi/spVypYk4kto/default.jpg )
    //                                     ^^^^^^^^^^^                                 ^^^^^^^^^^^
    $domain = parse_url($url,PHP_URL_HOST);
    if ($domain=='youtube.com' || $domain=='www.youtube.com')
    {
        parse_str(parse_url($url,PHP_URL_QUERY), $params); // Extract video ID and get thumbnail
        if (!empty($params['v'])) return array('src'=>'https://img.youtube.com/vi/'.$params['v'].'/default.jpg',
                                               'href'=>$href,'width'=>'120','height'=>'90','alt'=>'YouTube thumbnail');
    }
    if ($domain=='youtu.be') // Youtube short links
    {
        $path = parse_url($url,PHP_URL_PATH);
        return array('src'=>'https://img.youtube.com/vi'.$path.'/default.jpg',
                     'href'=>$href,'width'=>'120','height'=>'90','alt'=>'YouTube thumbnail');
    }
    if ($domain=='pix.toile-libre.org') // pix.toile-libre.org image hosting
    {
        parse_str(parse_url($url,PHP_URL_QUERY), $params); // Extract image filename.
        if (!empty($params) && !empty($params['img'])) return array('src'=>'http://pix.toile-libre.org/upload/thumb/'.urlencode($params['img']),
                                                                    'href'=>$href,'style'=>'max-width:120px; max-height:150px','alt'=>'pix.toile-libre.org thumbnail');
    }

    if ($domain=='imgur.com')
    {
        $path = parse_url($url,PHP_URL_PATH);
        if (startsWith($path,'/a/')) return array(); // Thumbnails for albums are not available.
        if (startsWith($path,'/r/')) return array('src'=>'https://i.imgur.com/'.basename($path).'s.jpg',
                                                  'href'=>$href,'width'=>'90','height'=>'90','alt'=>'imgur.com thumbnail');
        if (startsWith($path,'/gallery/')) return array('src'=>'https://i.imgur.com'.substr($path,8).'s.jpg',
                                                        'href'=>$href,'width'=>'90','height'=>'90','alt'=>'imgur.com thumbnail');

        if (substr_count($path,'/')==1) return array('src'=>'https://i.imgur.com/'.substr($path,1).'s.jpg',
                                                     'href'=>$href,'width'=>'90','height'=>'90','alt'=>'imgur.com thumbnail');
    }
    if ($domain=='i.imgur.com')
    {
        $pi = pathinfo(parse_url($url,PHP_URL_PATH));
        if (!empty($pi['filename'])) return array('src'=>'https://i.imgur.com/'.$pi['filename'].'s.jpg',
                                                  'href'=>$href,'width'=>'90','height'=>'90','alt'=>'imgur.com thumbnail');
    }
    if ($domain=='dailymotion.com' || $domain=='www.dailymotion.com')
    {
        if (strpos($url,'dailymotion.com/video/')!==false)
        {
            $thumburl=str_replace('dailymotion.com/video/','dailymotion.com/thumbnail/video/',$url);
            return array('src'=>$thumburl,
                         'href'=>$href,'width'=>'120','style'=>'height:auto;','alt'=>'DailyMotion thumbnail');
        }
    }
    if (endsWith($domain,'.imageshack.us'))
    {
        $ext=strtolower(pathinfo($url,PATHINFO_EXTENSION));
        if ($ext=='jpg' || $ext=='jpeg' || $ext=='png' || $ext=='gif')
        {
            $thumburl = substr($url,0,strlen($url)-strlen($ext)).'th.'.$ext;
            return array('src'=>$thumburl,
                         'href'=>$href,'width'=>'120','style'=>'height:auto;','alt'=>'imageshack.us thumbnail');
        }
    }

    // Some other hosts are SLOW AS HELL and usually require an extra HTTP request to get the thumbnail URL.
    // So we deport the thumbnail generation in order not to slow down page generation
    // (and we also cache the thumbnail)

    if (! $conf->get('thumbnail.enable_localcache')) return array(); // If local cache is disabled, no thumbnails for services which require the use a local cache.

    if ($domain=='flickr.com' || endsWith($domain,'.flickr.com')
        || $domain=='vimeo.com'
        || $domain=='ted.com' || endsWith($domain,'.ted.com')
        || $domain=='xkcd.com' || endsWith($domain,'.xkcd.com')
    )
    {
        if ($domain=='vimeo.com')
        {   // Make sure this vimeo URL points to a video (/xxx... where xxx is numeric)
            $path = parse_url($url,PHP_URL_PATH);
            if (!preg_match('!/\d+.+?!',$path)) return array(); // This is not a single video URL.
        }
        if ($domain=='xkcd.com' || endsWith($domain,'.xkcd.com'))
        {   // Make sure this URL points to a single comic (/xxx... where xxx is numeric)
            $path = parse_url($url,PHP_URL_PATH);
            if (!preg_match('!/\d+.+?!',$path)) return array();
        }
        if ($domain=='ted.com' || endsWith($domain,'.ted.com'))
        {   // Make sure this TED URL points to a video (/talks/...)
            $path = parse_url($url,PHP_URL_PATH);
            if ("/talks/" !== substr($path,0,7)) return array(); // This is not a single video URL.
        }
        $sign = hash_hmac('sha256', $url, $conf->get('credentials.salt')); // We use the salt to sign data (it's random, secret, and specific to each installation)
        return array('src'=>index_url($_SERVER).'?do=genthumbnail&hmac='.$sign.'&url='.urlencode($url),
                     'href'=>$href,'width'=>'120','style'=>'height:auto;','alt'=>'thumbnail');
    }

    // For all other, we try to make a thumbnail of links ending with .jpg/jpeg/png/gif
    // Technically speaking, we should download ALL links and check their Content-Type to see if they are images.
    // But using the extension will do.
    $ext=strtolower(pathinfo($url,PATHINFO_EXTENSION));
    if ($ext=='jpg' || $ext=='jpeg' || $ext=='png' || $ext=='gif')
    {
        $sign = hash_hmac('sha256', $url, $conf->get('credentials.salt')); // We use the salt to sign data (it's random, secret, and specific to each installation)
        return array('src'=>index_url($_SERVER).'?do=genthumbnail&hmac='.$sign.'&url='.urlencode($url),
                     'href'=>$href,'width'=>'120','style'=>'height:auto;','alt'=>'thumbnail');
    }
    return array(); // No thumbnail.

}


// Returns the HTML code to display a thumbnail for a link
// with a link to the original URL.
// Understands various services (youtube.com...)
// Input: $url = URL for which the thumbnail must be found.
//        $href = if provided, this URL will be followed instead of $url
// Returns '' if no thumbnail available.
function thumbnail($url,$href=false)
{
    // FIXME!
    global $conf;
    $t = computeThumbnail($conf, $url,$href);
    if (count($t)==0) return ''; // Empty array = no thumbnail for this URL.

    $html='<a href="'.escape($t['href']).'"><img src="'.escape($t['src']).'"';
    if (!empty($t['width']))  $html.=' width="'.escape($t['width']).'"';
    if (!empty($t['height'])) $html.=' height="'.escape($t['height']).'"';
    if (!empty($t['style']))  $html.=' style="'.escape($t['style']).'"';
    if (!empty($t['alt']))    $html.=' alt="'.escape($t['alt']).'"';
    $html.='></a>';
    return $html;
}

// Returns the HTML code to display a thumbnail for a link
// for the picture wall (using lazy image loading)
// Understands various services (youtube.com...)
// Input: $url = URL for which the thumbnail must be found.
//        $href = if provided, this URL will be followed instead of $url
// Returns '' if no thumbnail available.
function lazyThumbnail($conf, $url,$href=false)
{
    // FIXME!
    global $conf;
    $t = computeThumbnail($conf, $url,$href);
    if (count($t)==0) return ''; // Empty array = no thumbnail for this URL.

    $html='<a href="'.escape($t['href']).'">';

    // Lazy image
    $html.='<img class="b-lazy" src="#" data-src="'.escape($t['src']).'"';

    if (!empty($t['width']))  $html.=' width="'.escape($t['width']).'"';
    if (!empty($t['height'])) $html.=' height="'.escape($t['height']).'"';
    if (!empty($t['style']))  $html.=' style="'.escape($t['style']).'"';
    if (!empty($t['alt']))    $html.=' alt="'.escape($t['alt']).'"';
    $html.='>';

    // No-JavaScript fallback.
    $html.='<noscript><img src="'.escape($t['src']).'"';
    if (!empty($t['width']))  $html.=' width="'.escape($t['width']).'"';
    if (!empty($t['height'])) $html.=' height="'.escape($t['height']).'"';
    if (!empty($t['style']))  $html.=' style="'.escape($t['style']).'"';
    if (!empty($t['alt']))    $html.=' alt="'.escape($t['alt']).'"';
    $html.='></noscript></a>';

    return $html;
}


/**
 * Installation
 * This function should NEVER be called if the file data/config.php exists.
 *
 * @param ConfigManager $conf Configuration Manager instance.
 */
function install($conf)
{
    // On free.fr host, make sure the /sessions directory exists, otherwise login will not work.
    if (endsWith($_SERVER['HTTP_HOST'],'.free.fr') && !is_dir($_SERVER['DOCUMENT_ROOT'].'/sessions')) mkdir($_SERVER['DOCUMENT_ROOT'].'/sessions',0705);


    // This part makes sure sessions works correctly.
    // (Because on some hosts, session.save_path may not be set correctly,
    // or we may not have write access to it.)
    if (isset($_GET['test_session']) && ( !isset($_SESSION) || !isset($_SESSION['session_tested']) || $_SESSION['session_tested']!='Working'))
    {   // Step 2: Check if data in session is correct.
        echo '<pre>Sessions do not seem to work correctly on your server.<br>';
        echo 'Make sure the variable session.save_path is set correctly in your php config, and that you have write access to it.<br>';
        echo 'It currently points to '.session_save_path().'<br>';
        echo 'Check that the hostname used to access Shaarli contains a dot. On some browsers, accessing your server via a hostname like \'localhost\' or any custom hostname without a dot causes cookie storage to fail. We recommend accessing your server via it\'s IP address or Fully Qualified Domain Name.<br>';
        echo '<br><a href="?">Click to try again.</a></pre>';
        die;
    }
    if (!isset($_SESSION['session_tested']))
    {   // Step 1 : Try to store data in session and reload page.
        $_SESSION['session_tested'] = 'Working';  // Try to set a variable in session.
        header('Location: '.index_url($_SERVER).'?test_session');  // Redirect to check stored data.
    }
    if (isset($_GET['test_session']))
    {   // Step 3: Sessions are OK. Remove test parameter from URL.
        header('Location: '.index_url($_SERVER));
    }


    if (!empty($_POST['setlogin']) && !empty($_POST['setpassword']))
    {
        $tz = 'UTC';
        if (!empty($_POST['continent']) && !empty($_POST['city'])
            && isTimeZoneValid($_POST['continent'], $_POST['city'])
        ) {
            $tz = $_POST['continent'].'/'.$_POST['city'];
        }
        $conf->set('general.timezone', $tz);
        $login = $_POST['setlogin'];
        $conf->set('credentials.login', $login);
        $salt = sha1(uniqid('', true) .'_'. mt_rand());
        $conf->set('credentials.salt', $salt);
        $conf->set('credentials.hash', sha1($_POST['setpassword'] . $login . $salt));
        if (!empty($_POST['title'])) {
            $conf->set('general.title', escape($_POST['title']));
        } else {
            $conf->set('general.title', 'Shared links on '.escape(index_url($_SERVER)));
        }
        $conf->set('updates.check_updates', !empty($_POST['updateCheck']));
        try {
            // Everything is ok, let's create config file.
            $conf->write(isLoggedIn());
        }
        catch(Exception $e) {
            error_log(
                    'ERROR while writing config file after installation.' . PHP_EOL .
                    $e->getMessage()
                );

            // TODO: do not handle exceptions/errors in JS.
            echo '<script>alert("'. $e->getMessage() .'");document.location=\'?\';</script>';
            exit;
        }
        echo '<script>alert("Shaarli is now configured. Please enter your login/password and start shaaring your links!");document.location=\'?do=login\';</script>';
        exit;
    }

    // Display config form:
    list($timezone_form, $timezone_js) = generateTimeZoneForm();
    $timezone_html = '';
    if ($timezone_form != '') {
        $timezone_html = '<tr><td><b>Timezone:</b></td><td>'.$timezone_form.'</td></tr>';
    }

    $PAGE = new PageBuilder($conf);
    $PAGE->assign('timezone_html',$timezone_html);
    $PAGE->assign('timezone_js',$timezone_js);
    $PAGE->renderPage('install');
    exit;
}

/**
 * Because some f*cking services like flickr require an extra HTTP request to get the thumbnail URL,
 * I have deported the thumbnail URL code generation here, otherwise this would slow down page generation.
 * The following function takes the URL a link (e.g. a flickr page) and return the proper thumbnail.
 * This function is called by passing the URL:
 * http://mywebsite.com/shaarli/?do=genthumbnail&hmac=[HMAC]&url=[URL]
 * [URL] is the URL of the link (e.g. a flickr page)
 * [HMAC] is the signature for the [URL] (so that these URL cannot be forged).
 * The function below will fetch the image from the webservice and store it in the cache.
 *
 * @param ConfigManager $conf Configuration Manager instance,
 */
function genThumbnail($conf)
{
    // Make sure the parameters in the URL were generated by us.
    $sign = hash_hmac('sha256', $_GET['url'], $conf->get('credentials.salt'));
    if ($sign!=$_GET['hmac']) die('Naughty boy!');

    $cacheDir = $conf->get('resource.thumbnails_cache', 'cache');
    // Let's see if we don't already have the image for this URL in the cache.
    $thumbname=hash('sha1',$_GET['url']).'.jpg';
    if (is_file($cacheDir .'/'. $thumbname))
    {   // We have the thumbnail, just serve it:
        header('Content-Type: image/jpeg');
        echo file_get_contents($cacheDir .'/'. $thumbname);
        return;
    }
    // We may also serve a blank image (if service did not respond)
    $blankname=hash('sha1',$_GET['url']).'.gif';
    if (is_file($cacheDir .'/'. $blankname))
    {
        header('Content-Type: image/gif');
        echo file_get_contents($cacheDir .'/'. $blankname);
        return;
    }

    // Otherwise, generate the thumbnail.
    $url = $_GET['url'];
    $domain = parse_url($url,PHP_URL_HOST);

    if ($domain=='flickr.com' || endsWith($domain,'.flickr.com'))
    {
        // Crude replacement to handle new flickr domain policy (They prefer www. now)
        $url = str_replace('http://flickr.com/','http://www.flickr.com/',$url);

        // Is this a link to an image, or to a flickr page ?
        $imageurl='';
        if (endsWith(parse_url($url, PHP_URL_PATH), '.jpg'))
        {  // This is a direct link to an image. e.g. http://farm1.staticflickr.com/5/5921913_ac83ed27bd_o.jpg
            preg_match('!(http://farm\d+\.staticflickr\.com/\d+/\d+_\w+_)\w.jpg!',$url,$matches);
            if (!empty($matches[1])) $imageurl=$matches[1].'m.jpg';
        }
        else // This is a flickr page (html)
        {
            // Get the flickr html page.
            list($headers, $content) = get_http_response($url, 20);
            if (strpos($headers[0], '200 OK') !== false)
            {
                // flickr now nicely provides the URL of the thumbnail in each flickr page.
                preg_match('!<link rel=\"image_src\" href=\"(.+?)\"!', $content, $matches);
                if (!empty($matches[1])) $imageurl=$matches[1];

                // In albums (and some other pages), the link rel="image_src" is not provided,
                // but flickr provides:
                // <meta property="og:image" content="http://farm4.staticflickr.com/3398/3239339068_25d13535ff_z.jpg" />
                if ($imageurl=='')
                {
                    preg_match('!<meta property=\"og:image\" content=\"(.+?)\"!', $content, $matches);
                    if (!empty($matches[1])) $imageurl=$matches[1];
                }
            }
        }

        if ($imageurl!='')
        {   // Let's download the image.
            // Image is 240x120, so 10 seconds to download should be enough.
            list($headers, $content) = get_http_response($imageurl, 10);
            if (strpos($headers[0], '200 OK') !== false) {
                // Save image to cache.
                file_put_contents($cacheDir .'/'. $thumbname, $content);
                header('Content-Type: image/jpeg');
                echo $content;
                return;
            }
        }
    }

    elseif ($domain=='vimeo.com' )
    {
        // This is more complex: we have to perform a HTTP request, then parse the result.
        // Maybe we should deport this to JavaScript ? Example: http://stackoverflow.com/questions/1361149/get-img-thumbnails-from-vimeo/4285098#4285098
        $vid = substr(parse_url($url,PHP_URL_PATH),1);
        list($headers, $content) = get_http_response('https://vimeo.com/api/v2/video/'.escape($vid).'.php', 5);
        if (strpos($headers[0], '200 OK') !== false) {
            $t = unserialize($content);
            $imageurl = $t[0]['thumbnail_medium'];
            // Then we download the image and serve it to our client.
            list($headers, $content) = get_http_response($imageurl, 10);
            if (strpos($headers[0], '200 OK') !== false) {
                // Save image to cache.
                file_put_contents($cacheDir .'/'. $thumbname, $content);
                header('Content-Type: image/jpeg');
                echo $content;
                return;
            }
        }
    }

    elseif ($domain=='ted.com' || endsWith($domain,'.ted.com'))
    {
        // The thumbnail for TED talks is located in the <link rel="image_src" [...]> tag on that page
        // http://www.ted.com/talks/mikko_hypponen_fighting_viruses_defending_the_net.html
        // <link rel="image_src" href="http://images.ted.com/images/ted/28bced335898ba54d4441809c5b1112ffaf36781_389x292.jpg" />
        list($headers, $content) = get_http_response($url, 5);
        if (strpos($headers[0], '200 OK') !== false) {
            // Extract the link to the thumbnail
            preg_match('!link rel="image_src" href="(http://images.ted.com/images/ted/.+_\d+x\d+\.jpg)"!', $content, $matches);
            if (!empty($matches[1]))
            {   // Let's download the image.
                $imageurl=$matches[1];
                // No control on image size, so wait long enough
                list($headers, $content) = get_http_response($imageurl, 20);
                if (strpos($headers[0], '200 OK') !== false) {
                    $filepath = $cacheDir .'/'. $thumbname;
                    file_put_contents($filepath, $content); // Save image to cache.
                    if (resizeImage($filepath))
                    {
                        header('Content-Type: image/jpeg');
                        echo file_get_contents($filepath);
                        return;
                    }
                }
            }
        }
    }

    elseif ($domain=='xkcd.com' || endsWith($domain,'.xkcd.com'))
    {
        // There is no thumbnail available for xkcd comics, so download the whole image and resize it.
        // http://xkcd.com/327/
        // <img src="http://imgs.xkcd.com/comics/exploits_of_a_mom.png" title="<BLABLA>" alt="<BLABLA>" />
        list($headers, $content) = get_http_response($url, 5);
        if (strpos($headers[0], '200 OK') !== false) {
            // Extract the link to the thumbnail
            preg_match('!<img src="(http://imgs.xkcd.com/comics/.*)" title="[^s]!', $content, $matches);
            if (!empty($matches[1]))
            {   // Let's download the image.
                $imageurl=$matches[1];
                // No control on image size, so wait long enough
                list($headers, $content) = get_http_response($imageurl, 20);
                if (strpos($headers[0], '200 OK') !== false) {
                    $filepath = $cacheDir.'/'.$thumbname;
                    // Save image to cache.
                    file_put_contents($filepath, $content);
                    if (resizeImage($filepath))
                    {
                        header('Content-Type: image/jpeg');
                        echo file_get_contents($filepath);
                        return;
                    }
                }
            }
        }
    }

    else
    {
        // For all other domains, we try to download the image and make a thumbnail.
        // We allow 30 seconds max to download (and downloads are limited to 4 Mb)
        list($headers, $content) = get_http_response($url, 30);
        if (strpos($headers[0], '200 OK') !== false) {
            $filepath = $cacheDir .'/'.$thumbname;
            // Save image to cache.
            file_put_contents($filepath, $content);
            if (resizeImage($filepath))
            {
                header('Content-Type: image/jpeg');
                echo file_get_contents($filepath);
                return;
            }
        }
    }


    // Otherwise, return an empty image (8x8 transparent gif)
    $blankgif = base64_decode('R0lGODlhCAAIAIAAAP///////yH5BAEKAAEALAAAAAAIAAgAAAIHjI+py+1dAAA7');
    // Also put something in cache so that this URL is not requested twice.
    file_put_contents($cacheDir .'/'. $blankname, $blankgif);
    header('Content-Type: image/gif');
    echo $blankgif;
}

// Make a thumbnail of the image (to width: 120 pixels)
// Returns true if success, false otherwise.
function resizeImage($filepath)
{
    if (!function_exists('imagecreatefromjpeg')) return false; // GD not present: no thumbnail possible.

    // Trick: some stupid people rename GIF as JPEG... or else.
    // So we really try to open each image type whatever the extension is.
    $header=file_get_contents($filepath,false,NULL,0,256); // Read first 256 bytes and try to sniff file type.
    $im=false;
    $i=strpos($header,'GIF8'); if (($i!==false) && ($i==0)) $im = imagecreatefromgif($filepath); // Well this is crude, but it should be enough.
    $i=strpos($header,'PNG'); if (($i!==false) && ($i==1)) $im = imagecreatefrompng($filepath);
    $i=strpos($header,'JFIF'); if ($i!==false) $im = imagecreatefromjpeg($filepath);
    if (!$im) return false;  // Unable to open image (corrupted or not an image)
    $w = imagesx($im);
    $h = imagesy($im);
    $ystart = 0; $yheight=$h;
    if ($h>$w) { $ystart= ($h/2)-($w/2); $yheight=$w/2; }
    $nw = 120;   // Desired width
    $nh = min(floor(($h*$nw)/$w),120); // Compute new width/height, but maximum 120 pixels height.
    // Resize image:
    $im2 = imagecreatetruecolor($nw,$nh);
    imagecopyresampled($im2, $im, 0, 0, 0, $ystart, $nw, $nh, $w, $yheight);
    imageinterlace($im2,true); // For progressive JPEG.
    $tempname=$filepath.'_TEMP.jpg';
    imagejpeg($im2, $tempname, 90);
    imagedestroy($im);
    imagedestroy($im2);
    unlink($filepath);
    rename($tempname,$filepath);  // Overwrite original picture with thumbnail.
    return true;
}

if (isset($_SERVER['QUERY_STRING']) && startsWith($_SERVER['QUERY_STRING'], 'do=genthumbnail')) { genThumbnail($conf); exit; }  // Thumbnail generation/cache does not need the link database.
if (isset($_SERVER['QUERY_STRING']) && startsWith($_SERVER['QUERY_STRING'], 'do=dailyrss')) { showDailyRSS($conf); exit; }
if (!isset($_SESSION['LINKS_PER_PAGE'])) {
    $_SESSION['LINKS_PER_PAGE'] = $conf->get('general.links_per_page', 20);
}
renderPage($conf, $pluginManager);