aboutsummaryrefslogtreecommitdiffstats
path: root/include/zot.php
blob: 0fbeed519f51d99a0b318d0e20dc463080fc15db (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
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
<?php /** @file */

require_once('include/crypto.php');
require_once('include/items.php');

/**
 * Red implementation of zot protocol. 
 *
 * https://github.com/friendica/red/wiki/zot
 * https://github.com/friendica/red/wiki/Zot---A-High-Level-Overview
 *
 */


/**
 *
 * @function zot_new_uid($channel_nick)
 *
 *    Generates a unique string for use as a zot guid using our DNS-based url, the channel nickname and some entropy.
 *    The entropy ensures uniqueness against re-installs where the same URL and nickname are chosen.
 *    NOTE: zot doesn't require this to be unique. Internally we use a whirlpool hash of this guid and the signature
 *    of this guid signed with the channel private key. This can be verified and should make the probability of 
 *    collision of the verified result negligible within the constraints of our immediate universe.  
 *
 * @param string channel_nickname = unique nickname of controlling entity
 *
 * @returns string
 *
 */

function zot_new_uid($channel_nick) {
	$rawstr = z_root() . '/' . $channel_nick . '.' . mt_rand();
	return(base64url_encode(hash('whirlpool',$rawstr,true),true));
}


/**
 *
 * function make_xchan_hash($guid,$guid_sig)
 *
 * Generates a portable hash identifier for the channel identified by $guid and signed with $guid_sig
 * This ID is portable across the network but MUST be calculated locally by verifying the signature
 * and can not be trusted as an identity.
 *
 */

function make_xchan_hash($guid,$guid_sig) {
	return base64url_encode(hash('whirlpool',$guid . $guid_sig, true));
}

/**
 * @function zot_get_hublocs($hash)
 *     Given a zot hash, return all distinct hubs. 
 *     This function is used in building the zot discovery packet
 *     and therefore should only be used by channels which are defined
 *     on this hub
 * @param string $hash - xchan_hash
 * @retuns array of hubloc (hub location structures)
 *    hubloc_id          int
 *    hubloc_guid        char(255)
 *	  hubloc_guid_sig    text
 *    hubloc_hash        char(255)
 *    hubloc_addr        char(255)
 *    hubloc_flags       int
 *    hubloc_status      int
 *    hubloc_url         char(255)
 *    hubloc_url_sig     text
 *	  hubloc_host        char(255)
 *    hubloc_callback    char(255)
 *    hubloc_connect     char(255)
 *    hubloc_sitekey     text
 *    hubloc_updated     datetime
 *    hubloc_connected   datetime 	
 *
 */

function zot_get_hublocs($hash) {

	/** Only search for active hublocs - e.g. those that haven't been marked deleted */

	$ret = q("select * from hubloc where hubloc_hash = '%s' and not ( hubloc_flags & %d ) group by hubloc_url ",
		dbesc($hash),
		intval(HUBLOC_FLAGS_DELETED)
	);
	return $ret;
}
	 
/**
 *
 * @function zot_build_packet($channel,$type = 'notify',$recipients = null, $remote_key = null, $secret = null)
 *    builds a zot notification packet that you can either
 *    store in the queue with a message array or call zot_zot to immediately 
 *    zot it to the other side
 *
 * @param array $channel     => sender channel structure
 * @param string $type       => packet type: one of 'ping', 'pickup', 'purge', 'refresh', 'force_refresh', 'notify', 'auth_check'
 * @param array $recipients  => envelope information, array ( 'guid' => string, 'guid_sig' => string ); empty for public posts
 * @param string $remote_key => optional public site key of target hub used to encrypt entire packet
 *    NOTE: remote_key and encrypted packets are required for 'auth_check' packets, optional for all others 
 * @param string $secret     => random string, required for packets which require verification/callback
 *    e.g. 'pickup', 'purge', 'notify', 'auth_check'. Packet types 'ping', 'force_refresh', and 'refresh' do not require verification 
 *
 * @returns string json encoded zot packet
 */

function zot_build_packet($channel,$type = 'notify',$recipients = null, $remote_key = null, $secret = null) {

	$data = array(
		'type' => $type,
		'sender' => array(
			'guid' => $channel['channel_guid'],
			'guid_sig' => base64url_encode(rsa_sign($channel['channel_guid'],$channel['channel_prvkey'])),
			'url' => z_root(),
			'url_sig' => base64url_encode(rsa_sign(z_root(),$channel['channel_prvkey']))
		), 
		'callback' => '/post',
		'version' => ZOT_REVISION
	);

	if($recipients)
		$data['recipients'] = $recipients;

	if($secret) {
		$data['secret'] = $secret; 
		$data['secret_sig'] = base64url_encode(rsa_sign($secret,$channel['channel_prvkey']));
	}

	logger('zot_build_packet: ' . print_r($data,true), LOGGER_DATA);

	// Hush-hush ultra top-secret mode

	if($remote_key) {
		$data = crypto_encapsulate(json_encode($data),$remote_key);
	}

	return json_encode($data);
}


/**
 * @function: zot_zot
 * @param: string $url
 * @param: array $data
 *
 * @returns: array => see z_post_url for returned data format
 */
 


function zot_zot($url,$data) {
	return z_post_url($url,array('data' => $data));
}

/**
 * @function: zot_finger
 *
 * Look up information about channel
 * @param: string $webbie
 *   does not have to be host qualified e.g. 'foo' is treated as 'foo@thishub'
 * @param: array $channel
 *   (optional), if supplied permissions will be enumerated specifically for $channel
 * @param: boolean $autofallback
 *   fallback/failover to http if https connection cannot be established. Default is true.
 *
 * @returns: array => see z_post_url and mod/zfinger.php
 */


function zot_finger($webbie,$channel,$autofallback = true) {


	if(strpos($webbie,'@') === false) {
		$address = $webbie;
		$host = get_app()->get_hostname();
	}
	else {
		$address = substr($webbie,0,strpos($webbie,'@'));
		$host = substr($webbie,strpos($webbie,'@')+1);
	}

	$xchan_addr = $address . '@' . $host;

	if((! $address) || (! $xchan_addr)) {
		logger('zot_finger: no address :' . $webbie);
		return array('success' => false);
	}		

	// potential issue here; the xchan_addr points to the primary hub.
	// The webbie we were called with may not, so it might not be found
	// unless we query for hubloc_addr instead of xchan_addr

	$r = q("select xchan.*, hubloc.* from xchan 
			left join hubloc on xchan_hash = hubloc_hash
			where xchan_addr = '%s' and (hubloc_flags & %d) limit 1",
		dbesc($xchan_addr),
		intval(HUBLOC_FLAGS_PRIMARY)
	);

	if($r) {
		$url = $r[0]['hubloc_url'];
	}
	else {
		$url = 'https://' . $host;
	}
	
	$rhs = '/.well-known/zot-info';
	$https = ((strpos($url,'https://') === 0) ? true : false);

	logger('zot_finger: ' . $address . ' at ' . $url, LOGGER_DEBUG);

	if($channel) {
		$postvars = array(
			'address'    => $address,
			'target'     => $channel['channel_guid'],
			'target_sig' => $channel['channel_guid_sig'],
			'key'        => $channel['channel_pubkey']
		);

		$result = z_post_url($url . $rhs,$postvars);


		if((! $result['success']) && ($autofallback)) {
			if($https) {
				logger('zot_finger: https failed. falling back to http');
				$result = z_post_url('http://' . $host . $rhs,$postvars);
			}
		}
	}		
	else {
		$rhs .= '?f=&address=' . urlencode($address);

		$result =  z_fetch_url($url . $rhs);
		if((! $result['success']) && ($autofallback)) {
			if($https) {
				logger('zot_finger: https failed. falling back to http');
				$result = z_fetch_url('http://' . $host . $rhs);
			}
		}
	}
	
	if(! $result['success'])
		logger('zot_finger: no results');

	return $result;	 

}

/**
 * @function: zot_refresh($them, $channel = null, $force = false)
 *
 *   zot_refresh is typically invoked when somebody has changed permissions of a channel and they are notified
 *   to fetch new permissions via a finger/discovery operation. This may result in a new connection 
 *   (abook entry) being added to a local channel and it may result in auto-permissions being granted. 
 * 
 *   Friending in zot is accomplished by sending a refresh packet to a specific channel which indicates a
 *   permission change has been made by the sender which affects the target channel. The hub controlling
 *   the target channel does targetted discovery (a zot-finger request requesting permissions for the local
 *   channel). These are decoded here, and if necessary and abook structure (addressbook) is created to store
 *   the permissions assigned to this channel. 
 *   
 *   Initially these abook structures are created with a 'pending' flag, so that no reverse permissions are 
 *   implied until this is approved by the owner channel. A channel can also auto-populate permissions in 
 *   return and send back a refresh packet of its own. This is used by forum and group communication channels
 *   so that friending and membership in the channel's "club" is automatic. 
 * 
 * @param array $them => xchan structure of sender
 * @param array $channel => local channel structure of target recipient, required for "friending" operations
 *
 * @returns boolean true if successful, else false 
 */

function zot_refresh($them,$channel = null, $force = false) {

	logger('zot_refresh: them: ' . print_r($them,true), LOGGER_DATA);
	if($channel)
		logger('zot_refresh: channel: ' . print_r($channel,true), LOGGER_DATA);

	if($them['hubloc_url'])
		$url = $them['hubloc_url'];
	else {
		$r = q("select hubloc_url from hubloc where hubloc_hash = '%s' and ( hubloc_flags & %d ) limit 1",
			dbesc($them['xchan_hash']),
			intval(HUBLOC_FLAGS_PRIMARY)
		);
		if($r)
			$url = $r[0]['hubloc_url'];
	}
	if(! $url) {
		logger('zot_refresh: no url');
		return false;
	}

	$postvars = array();

	if($channel) {
		$postvars['target']     = $channel['channel_guid'];
		$postvars['target_sig'] = $channel['channel_guid_sig'];
		$postvars['key']        = $channel['channel_pubkey'];
	}

	if(array_key_exists('xchan_addr',$them) && $them['xchan_addr'])
		$postvars['address'] = $them['xchan_addr'];
	if(array_key_exists('xchan_hash',$them) && $them['xchan_hash'])
		$postvars['guid_hash'] = $them['xchan_hash'];
	if(array_key_exists('xchan_guid',$them) && $them['xchan_guid'] 
		&& array_key_exists('xchan_guid_sig',$them) && $them['xchan_guid_sig']) {
		$postvars['guid'] = $them['xchan_guid'];
		$postvars['guid_sig'] = $them['xchan_guid_sig'];
	}

	$rhs = '/.well-known/zot-info';

	$result = z_post_url($url . $rhs,$postvars);
	
	logger('zot_refresh: zot-info: ' . print_r($result,true), LOGGER_DATA);

	if($result['success']) {

		$j = json_decode($result['body'],true);

		if(! (($j) && ($j['success']))) {
			logger('zot_refresh: result not decodable');
			return false;
		}

		$x = import_xchan($j,(($force) ? UPDATE_FLAGS_FORCED : UPDATE_FLAGS_UPDATED));

		if(! $x['success'])
			return false;

		$their_perms = 0;

		if($channel) {
			$global_perms = get_perms();
			if($j['permissions']['data']) {
				$permissions = crypto_unencapsulate(array(
					'data' => $j['permissions']['data'],
					'key'  => $j['permissions']['key'],
					'iv'   => $j['permissions']['iv']),
					$channel['channel_prvkey']);
				if($permissions)
					$permissions = json_decode($permissions,true);
				logger('decrypted permissions: ' . print_r($permissions,true), LOGGER_DATA);
			}
			else
				$permissions = $j['permissions'];

			$connected_set = false;

			if($permissions && is_array($permissions)) {
				foreach($permissions as $k => $v) {
					// The connected permission means you are in their address book
					if($k === 'connected') {
						$connected_set = intval($v);
						continue;
					}	
					if(($v) && (array_key_exists($k,$global_perms))) {
						$their_perms = $their_perms | intval($global_perms[$k][1]);
					}
				}
			}

			$r = q("select * from abook where abook_xchan = '%s' and abook_channel = %d and not (abook_flags & %d) limit 1",
				dbesc($x['hash']),
				intval($channel['channel_id']),
				intval(ABOOK_FLAG_SELF)
			);

			if(array_key_exists('profile',$j) && array_key_exists('next_birthday',$j['profile'])) {	
				$next_birthday = datetime_convert('UTC','UTC',$j['profile']['next_birthday']);
			}
			else {
				$next_birthday = '0000-00-00 00:00:00';
			}

			if($r) {

				// if the dob is the same as what we have stored (disregarding the year), keep the one 
				// we have as we may have updated the year after sending a notification; and resetting
				// to the one we just received would cause us to create duplicated events. 

				if(substr($r[0]['abook_dob'],5) == substr($next_birthday,5))
					$next_birthday = $r[0]['abook_dob'];

				$current_abook_connected = (($r[0]['abook_flags'] & ABOOK_FLAG_UNCONNECTED) ? 0 : 1);
		
				$y = q("update abook set abook_their_perms = %d, abook_dob = '%s'
					where abook_xchan = '%s' and abook_channel = %d 
					and not (abook_flags & %d) limit 1",
					intval($their_perms),
					dbesc($next_birthday),
					dbesc($x['hash']),
					intval($channel['channel_id']),
					intval(ABOOK_FLAG_SELF)
				);

//				if(($connected_set === 0 || $connected_set === 1) && ($connected_set !== $current_abook_unconnected)) {

					// if they are in your address book but you aren't in theirs, and/or this does not
					// match your current connected state setting, toggle it. 

//					$y1 = q("update abook set abook_flags = (abook_flags ^ %d)
//						where abook_xchan = '%s' and abook_channel = %d 
//						and not (abook_flags & %d) limit 1",
//						intval(ABOOK_FLAG_UNCONNECTED),
//						dbesc($x['hash']),
//						intval($channel['channel_id']),
//						intval(ABOOK_FLAG_SELF)
//					);
//				}

				if(! $y)
					logger('abook update failed');
				else {
					// if we were just granted read stream permission and didn't have it before, try to pull in some posts
					if((! ($r[0]['abook_their_perms'] & PERMS_R_STREAM)) && ($their_perms & PERMS_R_STREAM))
						proc_run('php','include/onepoll.php',$r[0]['abook_id']); 
				}
			}
			else {
				$default_perms = 0;
				// look for default permissions to apply in return - e.g. auto-friend
				$z = q("select * from abook where abook_channel = %d and (abook_flags & %d) limit 1",
					intval($channel['channel_id']),
					intval(ABOOK_FLAG_SELF)
				);

				if($z)
					$default_perms = intval($z[0]['abook_my_perms']);		

				// Keep original perms to check if we need to notify them
				$previous_perms = get_all_perms($channel['channel_id'],$x['hash']);

				$y = q("insert into abook ( abook_account, abook_channel, abook_xchan, abook_their_perms, abook_my_perms, abook_created, abook_updated, abook_dob, abook_flags ) values ( %d, %d, '%s', %d, %d, '%s', '%s', '%s', %d )",
					intval($channel['channel_account_id']),
					intval($channel['channel_id']),
					dbesc($x['hash']),
					intval($their_perms),
					intval($default_perms),
					dbesc(datetime_convert()),
					dbesc(datetime_convert()),
					dbesc($next_birthday),
					intval(($default_perms) ? 0 : ABOOK_FLAG_PENDING)
				);

				if($y) {
					logger("New introduction received for {$channel['channel_name']}");
					$new_perms = get_all_perms($channel['channel_id'],$x['hash']);
					if($new_perms != $previous_perms) {
						// Send back a permissions update if permissions have changed
						$z = q("select * from abook where abook_xchan = '%s' and abook_channel = %d and not (abook_flags & %d) limit 1",
							dbesc($x['hash']),
							intval($channel['channel_id']),
							intval(ABOOK_FLAG_SELF)
						);
						if($z)
							proc_run('php','include/notifier.php','permission_update',$z[0]['abook_id']);
					}
					$new_connection = q("select abook_id, abook_flags from abook where abook_channel = %d and abook_xchan = '%s' order by abook_created desc limit 1",
						intval($channel['channel_id']),
						dbesc($x['hash'])
					);
					if($new_connection) {
						require_once('include/enotify.php');
						notification(array(
							'type'         => NOTIFY_INTRO,
							'from_xchan'   => $x['hash'],
							'to_xchan'     => $channel['channel_hash'],
							'link'		   => z_root() . '/connedit/' . $new_connection[0]['abook_id'],
						));
					}

					if($new_connection && ($their_perms & PERMS_R_STREAM)) {
						if(($channel['channel_w_stream'] & PERMS_PENDING)
							|| (! ($new_connection[0]['abook_flags'] & ABOOK_FLAG_PENDING)) )
							proc_run('php','include/onepoll.php',$new_connection[0]['abook_id']); 
					}

				}
			}
		}
		return true;
	}
	return false;
}

/**
 * @function: zot_gethub
 *
 * A guid and a url, both signed by the sender, distinguish a known sender at a known location
 * This function looks these up to see if the channel is known and therefore previously verified. 
 * If not, we will need to verify it.
 *
 * @param array $arr
 *    $arr must contain: 
 *       string $arr['guid'] => guid of conversant
 *       string $arr['guid_sig'] => guid signed with conversant's private key
 *       string $arr['url'] => URL of the origination hub of this communication
 *       string $arr['url_sig'] => URL signed with conversant's private key
 *  
 *
 * @returns: array => hubloc record
 */


		
function zot_gethub($arr) {

	if($arr['guid'] && $arr['guid_sig'] && $arr['url'] && $arr['url_sig']) {
		$r = q("select * from hubloc 
				where hubloc_guid = '%s' and hubloc_guid_sig = '%s' 
				and hubloc_url = '%s' and hubloc_url_sig = '%s'
				limit 1",
			dbesc($arr['guid']),
			dbesc($arr['guid_sig']),
			dbesc($arr['url']),
			dbesc($arr['url_sig'])
		);
		if($r && count($r)) {
			logger('zot_gethub: found', LOGGER_DEBUG);
			return $r[0];
		}
	}
	logger('zot_gethub: not found: ' . print_r($arr,true), LOGGER_DEBUG);
	return null;
}

/**
 * @function zot_register_hub($arr)
 *
 *   A communication has been received which has an unknown (to us) sender. 
 *   Perform discovery based on our calculated hash of the sender at the origination address.
 *   This will fetch the discovery packet of the sender, which contains the public key we 
 *   need to verify our guid and url signatures.
 *
 * @param array $arr
 *    $arr must contain: 
 *       string $arr['guid'] => guid of conversant
 *       string $arr['guid_sig'] => guid signed with conversant's private key
 *       string $arr['url'] => URL of the origination hub of this communication
 *       string $arr['url_sig'] => URL signed with conversant's private key
 *  
 *
 * @returns array => 'success' (boolean true or false)
 *                   'message' (optional error string only if success is false)
 */


function zot_register_hub($arr) {

	$result = array('success' => false);

	if($arr['url'] && $arr['url_sig'] && $arr['guid'] && $arr['guid_sig']) {

		$guid_hash = make_xchan_hash($arr['guid'],$arr['guid_sig']);

		$url = $arr['url'] . '/.well-known/zot-info/?f=&guid_hash=' . $guid_hash;

		logger('zot_register_hub: ' . $url, LOGGER_DEBUG);

		$x = z_fetch_url($url);

		logger('zot_register_hub: ' . print_r($x,true), LOGGER_DATA);

		if($x['success']) {
			$record = json_decode($x['body'],true);

			/* 
			 * We now have a key - only continue registration if our signatures are valid 
			 * AND the guid and guid sig in the returned packet match those provided in
			 * our current communication.
			 */

			if((rsa_verify($arr['guid'],base64url_decode($arr['guid_sig']),$record['key']))
				&& (rsa_verify($arr['url'],base64url_decode($arr['url_sig']),$record['key']))
				&& ($arr['guid'] === $record['guid'])
				&& ($arr['guid_sig'] === $record['guid_sig'])) {

				$c = import_xchan($record);
				if($c['success'])
					$result['success'] = true;
			}
			else {
				logger('zot_register_hub: failure to verify returned packet.');
			}			
		}
	}
	return $result;
}


/**
 * @function import_xchan($arr,$ud_flags = UPDATE_FLAGS_UPDATED)
 *   Takes an associative array of a fetched discovery packet and updates
 *   all internal data structures which need to be updated as a result.
 * 
 * @param array $arr => json_decoded discovery packet
 * @param int $ud_flags
 *    Determines whether to create a directory update record if any changes occur, default is UPDATE_FLAGS_UPDATED
 *    $ud_flags = UPDATE_FLAGS_FORCED indicates a forced refresh where we unconditionally create a directory update record
 *      this typically occurs once a month for each channel as part of a scheduled ping to notify the directory
 *      that the channel still exists
 * @param array $ud_arr
 *    If set [typically by update_directory_entry()] indicates a specific update table row and more particularly 
 *    contains a particular address (ud_addr) which needs to be updated in that table.
 *
 * @returns array =>  'success' (boolean true or false)
 *                    'message' (optional error string only if success is false)
 */

function import_xchan($arr,$ud_flags = UPDATE_FLAGS_UPDATED, $ud_arr = null) {


	call_hooks('import_xchan', $arr);

	$ret = array('success' => false);
	$dirmode = intval(get_config('system','directory_mode')); 

	$changed = false;
	$what = '';

	if(! (is_array($arr) && array_key_exists('success',$arr) && $arr['success'])) {
		logger('import_xchan: invalid data packet: ' . print_r($arr,true));
		$ret['message'] = t('Invalid data packet');
		return $ret;
	}


	$xchan_hash = make_xchan_hash($arr['guid'],$arr['guid_sig']);
	$import_photos = false;

	if(! rsa_verify($arr['guid'],base64url_decode($arr['guid_sig']),$arr['key'])) {
		logger('import_xchan: Unable to verify channel signature for ' . $arr['address']);
		$ret['message'] = t('Unable to verify channel signature');
		return $ret;
	}

	logger('import_xchan: ' . $xchan_hash, LOGGER_DEBUG);

	$r = q("select * from xchan where xchan_hash = '%s' limit 1",
		dbesc($xchan_hash)
	);	

	if(! array_key_exists('connect_url', $arr))
		$arr['connect_url'] = '';		
			
	if(strpos($arr['address'],'/') !== false)
		$arr['address'] = substr($arr['address'],0,strpos($arr['address'],'/'));

	if($r) {
		if($r[0]['xchan_photo_date'] != $arr['photo_updated'])
			$import_photos = true;

		// if we import an entry from a site that's not ours and either or both of us is off the grid - hide the entry.
		// TODO: check if we're the same directory realm, which would mean we are allowed to see it

		$dirmode = get_config('system','directory_mode'); 

		if((($arr['site']['directory_mode'] === 'standalone') || ($dirmode & DIRECTORY_MODE_STANDALONE))
&& ($arr['site']['url'] != z_root()))
			$arr['searchable'] = false;

		$hidden = (1 - intval($arr['searchable']));

		// Be careful - XCHAN_FLAGS_HIDDEN should evaluate to 1
		if(($r[0]['xchan_flags'] & XCHAN_FLAGS_HIDDEN) != $hidden)
			$new_flags = $r[0]['xchan_flags'] ^ XCHAN_FLAGS_HIDDEN;
		else
			$new_flags = $r[0]['xchan_flags'];

		$adult = (($r[0]['xchan_flags'] & XCHAN_FLAGS_SELFCENSORED) ? true : false);
		$adult_changed =  ((intval($adult) != intval($arr['adult_content'])) ? true : false);
		if($adult_changed)
			$new_flags = $new_flags ^ XCHAN_FLAGS_SELFCENSORED;

		$deleted = (($r[0]['xchan_flags'] & XCHAN_FLAGS_DELETED) ? true : false);
		$deleted_changed =  ((intval($deleted) != intval($arr['deleted'])) ? true : false);
		if($deleted_changed)
			$new_flags = $new_flags ^ XCHAN_FLAGS_DELETED;

		if(($r[0]['xchan_name_date'] != $arr['name_updated']) 
			|| ($r[0]['xchan_connurl'] != $arr['connections_url']) 
			|| ($r[0]['xchan_flags'] != $new_flags)
			|| ($r[0]['xchan_addr'] != $arr['address'])
			|| ($r[0]['xchan_follow'] != $arr['follow_url'])
			|| ($r[0]['xchan_connpage'] != $arr['connect_url']) 
			|| ($r[0]['xchan_url'] != $arr['url'])) {
			$r = q("update xchan set xchan_name = '%s', xchan_name_date = '%s', xchan_connurl = '%s', xchan_follow = '%s', 
				xchan_connpage = '%s', xchan_flags = %d,
				xchan_addr = '%s', xchan_url = '%s' where xchan_hash = '%s' limit 1",
				dbesc($arr['name']),
				dbesc($arr['name_updated']),
				dbesc($arr['connections_url']),
				dbesc($arr['follow_url']),
				dbesc($arr['connect_url']),
				intval($new_flags),
				dbesc($arr['address']),
				dbesc($arr['url']),
				dbesc($xchan_hash)
			);

			logger('import_xchan: existing: ' . print_r($r[0],true), LOGGER_DATA);
			logger('import_xchan: new: ' . print_r($arr,true), LOGGER_DATA);
			$what .= 'xchan ';
			$changed = true;
		}
	}
	else {
		$import_photos = true;


		if((($arr['site']['directory_mode'] === 'standalone') || ($dirmode & DIRECTORY_MODE_STANDALONE))
&& ($arr['site']['url'] != z_root()))
			$arr['searchable'] = false;

		$hidden = (1 - intval($arr['searchable']));

		if($hidden)
			$new_flags = XCHAN_FLAGS_HIDDEN;
		else
			$new_flags = 0;
		if($arr['adult_content'])
			$new_flags |= XCHAN_FLAGS_SELFCENSORED;
		if(array_key_exists('deleted',$arr) && $arr['deleted'])
			$new_flags |= XCHAN_FLAGS_DELETED;
		
		$x = q("insert into xchan ( xchan_hash, xchan_guid, xchan_guid_sig, xchan_pubkey, xchan_photo_mimetype,
				xchan_photo_l, xchan_addr, xchan_url, xchan_connurl, xchan_follow, xchan_connpage, xchan_name, xchan_network, xchan_photo_date, xchan_name_date, xchan_flags)
				values ( '%s', '%s', '%s', '%s' , '%s', '%s', '%s', '%s', '%s', '%s', '%s', '%s', '%s', '%s', '%s', %d) ",
			dbesc($xchan_hash),
			dbesc($arr['guid']),
			dbesc($arr['guid_sig']),
			dbesc($arr['key']),
			dbesc($arr['photo_mimetype']),
			dbesc($arr['photo']),
			dbesc($arr['address']),
			dbesc($arr['url']),
			dbesc($arr['connections_url']),
			dbesc($arr['follow_url']),
			dbesc($arr['connect_url']),
			dbesc($arr['name']),
			dbesc('zot'),
			dbesc($arr['photo_updated']),
			dbesc($arr['name_updated']),
			intval($new_flags)
		);

		$what .= 'new_xchan';
		$changed = true;

	}				


	if($import_photos) {

		require_once('include/photo/photo_driver.php');

		// see if this is a channel clone that's hosted locally - which we treat different from other xchans/connections

		$local = q("select channel_account_id, channel_id from channel where channel_hash = '%s' limit 1",
			dbesc($xchan_hash)
		);
		if($local) {
			$ph = z_fetch_url($arr['photo'],true);
			if($ph['success']) {
				import_channel_photo($ph['body'], $arr['photo_mimetype'], $local[0]['channel_account_id'],$local[0]['channel_id']);
				// reset the names in case they got messed up when we had a bug in this function
				$photos = array(
					z_root() . '/photo/profile/l/' . $local[0]['channel_id'],
					z_root() . '/photo/profile/m/' . $local[0]['channel_id'],
					z_root() . '/photo/profile/s/' . $local[0]['channel_id'],
					$arr['photo_mimetype'],
					false
				);
			}
		}
		else {
			$photos = import_profile_photo($arr['photo'],$xchan_hash);
		}
		if($photos) {
			if($photos[4]) {
				// importing the photo failed somehow. Leave the photo_date alone so we can try again at a later date.
				// This often happens when somebody joins the matrix with a bad cert. 
				$r = q("update xchan set xchan_photo_l = '%s', xchan_photo_m = '%s', xchan_photo_s = '%s', xchan_photo_mimetype = '%s'
					where xchan_hash = '%s' limit 1",
					dbesc($photos[0]),
					dbesc($photos[1]),
					dbesc($photos[2]),
					dbesc($photos[3]),
					dbesc($xchan_hash)
				);
			}
			else {
				$r = q("update xchan set xchan_photo_date = '%s', xchan_photo_l = '%s', xchan_photo_m = '%s', xchan_photo_s = '%s', xchan_photo_mimetype = '%s'
					where xchan_hash = '%s' limit 1",
					dbesc(datetime_convert('UTC','UTC',$arr['photo_updated'])),
					dbesc($photos[0]),
					dbesc($photos[1]),
					dbesc($photos[2]),
					dbesc($photos[3]),
					dbesc($xchan_hash)
				);
			}
			$what .= 'photo ';
			$changed = true;
		}
	}

	// what we are missing for true hub independence is for any changes in the primary hub to 
	// get reflected not only in the hublocs, but also to update the URLs and addr in the appropriate xchan

	if($arr['locations']) {

		$xisting = q("select hubloc_id, hubloc_url, hubloc_sitekey from hubloc where hubloc_hash = '%s'",
			dbesc($xchan_hash)
		);

		// See if a primary is specified

		$has_primary = false;
		foreach($arr['locations'] as $location) {
			if($location['primary']) {
				$has_primary = true;
				break;
			}
		}

		foreach($arr['locations'] as $location) {
			if(! rsa_verify($location['url'],base64url_decode($location['url_sig']),$arr['key'])) {
				logger('import_xchan: Unable to verify site signature for ' . $location['url']);
				$ret['message'] .= sprintf( t('Unable to verify site signature for %s'), $location['url']) . EOL;
				continue;
			}

			// Ensure that they have one primary hub

			if(! $has_primary)
				$location['primary'] = true;


			for($x = 0; $x < count($xisting); $x ++) {
				if(($xisting[$x]['hubloc_url'] === $location['url']) && ($xisting[$x]['hubloc_sitekey'] === $location['sitekey'])) {
					$xisting[$x]['updated'] = true;
				}
			}

			if(! $location['sitekey']) {
				logger('import_xchan: empty hubloc sitekey. ' . print_r($location,true));
				continue;
			}

			// Catch some malformed entries from the past which still exist

			if(strpos($location['address'],'/') !== false)
				$location['address'] = substr($location['address'],0,strpos($location['address'],'/'));

			// match as many fields as possible in case anything at all changed. 

			$r = q("select * from hubloc where hubloc_hash = '%s' and hubloc_guid = '%s' and hubloc_guid_sig = '%s' and hubloc_url = '%s' and hubloc_url_sig = '%s' and hubloc_host = '%s' and hubloc_addr = '%s' and hubloc_callback = '%s' and hubloc_sitekey = '%s' ",
				dbesc($xchan_hash),
				dbesc($arr['guid']),
				dbesc($arr['guid_sig']),
				dbesc($location['url']),
				dbesc($location['url_sig']),
				dbesc($location['host']),
				dbesc($location['address']),
				dbesc($location['callback']),
				dbesc($location['sitekey'])
			);
			if($r) {
				logger('import_xchan: hub exists: ' . $location['url']);
				// update connection timestamp if this is the site we're talking to
				if($location['url'] == $arr['site']['url']) {
					q("update hubloc set hubloc_connected = '%s', hubloc_updated = '%s' where hubloc_id = %d limit 1",
						dbesc(datetime_convert()),
						dbesc(datetime_convert()),
						intval($r[0]['hubloc_id'])
					);
				}
				if($r[0]['hubloc_status'] & HUBLOC_OFFLINE) {
					q("update hubloc set hubloc_status = (hubloc_status ^ %d) where hubloc_id = %d limit 1",
						intval(HUBLOC_OFFLINE),
						intval($r[0]['hubloc_id'])
					);
					if($r[0]['hubloc_flags'] & HUBLOC_FLAGS_ORPHANCHECK) {
						q("update hubloc set hubloc_flags = (hubloc_flags ^ %d) where hubloc_id = %d limit 1",
							intval(HUBLOC_FLAGS_ORPHANCHECK),
							intval($r[0]['hubloc_id'])
						);
					}
					q("update xchan set xchan_flags = (xchan_flags ^ %d) where (xchan_flags & %d) and xchan_hash = '%s' limit 1",
						intval(XCHAN_FLAGS_ORPHAN),
						intval(XCHAN_FLAGS_ORPHAN),
						dbesc($xchan_hash)
					);

				} 

				// Remove pure duplicates
				if(count($r) > 1) {
					for($h = 1; $h < count($r); $h ++) {
						q("delete from hubloc where hubloc_id = %d limit 1",
							intval($r[$h]['hubloc_id'])
						);
					}
				}

				if((($r[0]['hubloc_flags'] & HUBLOC_FLAGS_PRIMARY) && (! $location['primary']))
					|| ((! ($r[0]['hubloc_flags'] & HUBLOC_FLAGS_PRIMARY)) && ($location['primary']))) {
					$r = q("update hubloc set hubloc_flags = (hubloc_flags ^ %d), hubloc_updated = '%s' where hubloc_id = %d limit 1",
						intval(HUBLOC_FLAGS_PRIMARY),
						dbesc(datetime_convert()),
						intval($r[0]['hubloc_id'])
					);
					$what = 'primary_hub ';
					$changed = true;
				}
				if((($r[0]['hubloc_flags'] & HUBLOC_FLAGS_DELETED) && (! $location['deleted']))
					|| ((! ($r[0]['hubloc_flags'] & HUBLOC_FLAGS_DELETED)) && ($location['deleted']))) {
					$r = q("update hubloc set hubloc_flags = (hubloc_flags ^ %d), hubloc_updated = '%s' where hubloc_id = %d limit 1",
						intval(HUBLOC_FLAGS_DELETED),
						dbesc(datetime_convert()),
						intval($r[0]['hubloc_id'])
					);
					$what = 'delete_hub ';
					$changed = true;
				}
				continue;
			}

			// new hub claiming to be primary. Make it so.

			if(intval($location['primary'])) {
				$r = q("update hubloc set hubloc_flags = (hubloc_flags ^ %d), hubloc_updated = '%s' where hubloc_hash = '%s' and (hubloc_flags & %d )",
					intval(HUBLOC_FLAGS_PRIMARY),
					dbesc(datetime_convert()),
					dbesc($xchan_hash),
					intval(HUBLOC_FLAGS_PRIMARY)
				);
			}
			logger('import_xchan: new hub: ' . $location['url']);
			$r = q("insert into hubloc ( hubloc_guid, hubloc_guid_sig, hubloc_hash, hubloc_addr, hubloc_flags, hubloc_url, hubloc_url_sig, hubloc_host, hubloc_callback, hubloc_sitekey, hubloc_updated, hubloc_connected)
					values ( '%s','%s','%s','%s', %d ,'%s','%s','%s','%s','%s','%s','%s')",
				dbesc($arr['guid']),
				dbesc($arr['guid_sig']),
				dbesc($xchan_hash),
				dbesc($location['address']),
				intval((intval($location['primary'])) ? HUBLOC_FLAGS_PRIMARY : 0),
				dbesc($location['url']),
				dbesc($location['url_sig']),
				dbesc($location['host']),
				dbesc($location['callback']),
				dbesc($location['sitekey']),
				dbesc(datetime_convert()),
				dbesc(datetime_convert())
			);
			$what .= 'newhub ';
			$changed = true;

		}

		// get rid of any hubs we have for this channel which weren't reported.
		// This was needed at one time to resolve complicated cross-site inconsistencies, but can cause sync conflict.
		// currently disabled.

//		if($xisting) {
//			foreach($xisting as $x) {
//				if(! array_key_exists('updated',$x)) {
//					logger('import_xchan: removing unreferenced hub location ' . $x['hubloc_url']);
//					$r = q("delete from hubloc where hubloc_id = %d limit 1",
//						intval($x['hubloc_id'])
//					);
//					$what .= 'removed_hub';
//					$changed = true;
//				}
//			}
//		}

	}

	// Which entries in the update table are we interested in updating?

	$address = (($ud_arr && $ud_arr['ud_addr']) ? $ud_arr['ud_addr'] : $arr['address']);


	// Are we a directory server of some kind?

	if($dirmode != DIRECTORY_MODE_NORMAL) {
		if(array_key_exists('profile',$arr) && is_array($arr['profile'])) {
			$profile_changed = import_directory_profile($xchan_hash,$arr['profile'],$address,$ud_flags, 1);
			if($profile_changed) {
				$what .= 'profile ';
				$changed = true;
			}
		}
		else {
			logger('import_xchan: profile not available - hiding');
			// they may have made it private
			$r = q("delete from xprof where xprof_hash = '%s' limit 1",
				dbesc($xchan_hash)
			);
			$r = q("delete from xtag where xtag_hash = '%s' limit 1",
				dbesc($xchan_hash)
			);
		}
	}

	if(array_key_exists('site',$arr) && is_array($arr['site'])) {
		$profile_changed = import_site($arr['site'],$arr['key']);
		if($profile_changed) {
			$what .= 'site ';
			$changed = true;
		}
	}
	

	if(($changed) || ($ud_flags == UPDATE_FLAGS_FORCED)) {
		$guid = random_string() . '@' . get_app()->get_hostname();		
		update_modtime($xchan_hash,$guid,$address,$ud_flags);
		logger('import_xchan: changed: ' . $what,LOGGER_DEBUG);
	}
	elseif(! $ud_flags) {
		// nothing changed but we still need to update the updates record
		q("update updates set ud_flags = ( ud_flags | %d ) where ud_addr = '%s' and not (ud_flags & %d) ",
			intval(UPDATE_FLAGS_UPDATED),
			dbesc($address),
			intval(UPDATE_FLAGS_UPDATED)
		);
	}

	if(! x($ret,'message')) {
		$ret['success'] = true;
		$ret['hash'] = $xchan_hash;
	}



	logger('import_xchan: result: ' . print_r($ret,true), LOGGER_DATA);
	return $ret;
}

/**
 * @function zot_process_response($hub,$arr,$outq) {
 *    Called immediately after sending a zot message which is using queue processing
 *    Updates the queue item according to the response result and logs any information
 *    returned to aid communications troubleshooting.
 *
 * @param string $hub - url of site we just contacted
 * @param array $arr - output of z_post_url()
 * @param array $outq - The queue structure attached to this request
 *
 * @returns nothing
 */


function zot_process_response($hub,$arr,$outq) {

	if(! $arr['success']) {
		logger('zot_process_response: failed: ' . $hub);
		return;
	}

	$x = json_decode($arr['body'],true);

	if(! $x) {
		logger('zot_process_response: No json from ' . $hub);
		logger('zot_process_response: headers: ' . print_r($arr['header'],true), LOGGER_DATA);
	}

	// synchronous message types are handled immediately
	// async messages remain in the queue until processed.

	if(intval($outq['outq_async'])) {
		$r = q("update outq set outq_delivered = 1, outq_updated = '%s' where outq_hash = '%s' and outq_channel = %d limit 1",
			dbesc(datetime_convert()),
			dbesc($outq['outq_hash']),
			intval($outq['outq_channel'])
		);
	}
	else {
		$r = q("delete from outq where outq_hash = '%s' and outq_channel = %d limit 1",
			dbesc($outq['outq_hash']),
			intval($outq['outq_channel'])
		);
	}

	logger('zot_process_response: ' . print_r($x,true), LOGGER_DATA);
}

/**
 * @function zot_fetch($arr)
 *
 *     We received a notification packet (in mod/post.php) that a message is waiting for us, and we've verified the sender.
 *     Now send back a pickup message, using our message tracking ID ($arr['secret']), which we will sign with our site private key.
 *     The entire pickup message is encrypted with the remote site's public key. 
 *     If everything checks out on the remote end, we will receive back a packet containing one or more messages,
 *     which will be processed and delivered before this function ultimately returns.
 *   
 * @param array $arr
 *     decrypted and json decoded notify packet from remote site
 */
 

function zot_fetch($arr) {

	logger('zot_fetch: ' . print_r($arr,true), LOGGER_DATA);

	$url = $arr['sender']['url'] . $arr['callback'];

	$ret_hub = zot_gethub($arr['sender']);
	if(! $ret_hub) {
		logger('zot_fetch: no hub: ' . print_r($arr['sender'],true));
		return;
	}

	$data = array(
		'type'    => 'pickup',
		'url'     => z_root(),
		'callback_sig' => base64url_encode(rsa_sign(z_root() . '/post',get_config('system','prvkey'))),
		'callback' => z_root() . '/post',
		'secret' => $arr['secret'],
		'secret_sig' => base64url_encode(rsa_sign($arr['secret'],get_config('system','prvkey')))
	);

	$datatosend = json_encode(crypto_encapsulate(json_encode($data),$ret_hub['hubloc_sitekey']));
	
	$fetch = zot_zot($url,$datatosend);
	$result = zot_import($fetch, $arr['sender']['url']);
	return $result;
}

/**
 * @function zot_import
 * 
 * Process an incoming array of messages which were obtained via pickup, and 
 * import, update, delete as directed.
 * 
 * @param array $arr => 'pickup' structure returned from remote site
 * @param string $sender_url => the url specified by the sender in the initial communication
 *       we will verify the sender and url in each returned message structure and also verify
 *       that all the messages returned match the site url that we are currently processing.
 * 
 * The message types handled here are 'activity' (e.g. posts), 'mail' , 'profile', and 'channel_sync'
 * 
 * @returns array => array ( [0] => string $channel_hash, [1] => string $delivery_status, [2] => string $address )
 *    suitable for logging remotely, enumerating the processing results of each message/recipient combination.
 * 
 */

function zot_import($arr, $sender_url) {

	$data = json_decode($arr['body'],true);

	if(! $data) {
		logger('zot_import: empty body');
		return array();
	}

	if(array_key_exists('iv',$data)) {
		$data = json_decode(crypto_unencapsulate($data,get_config('system','prvkey')),true);
	}

	$incoming = $data['pickup'];

	$return = array();

	if(is_array($incoming)) {
		foreach($incoming as $i) {
			$result = null;

			if(array_key_exists('iv',$i['notify'])) {
				$i['notify'] = json_decode(crypto_unencapsulate($i['notify'],get_config('system','prvkey')),true);
	  		}

			logger('zot_import: notify: ' . print_r($i['notify'],true), LOGGER_DATA);

			$hub = zot_gethub($i['notify']['sender']);			
			if((! $hub) || ($hub['hubloc_url'] != $sender_url)) {
				logger('zot_import: potential forgery: wrong site for sender: ' . $sender_url . ' != ' . print_r($i['notify'],true));
				continue;
			}


			$i['notify']['sender']['hash'] = make_xchan_hash($i['notify']['sender']['guid'],$i['notify']['sender']['guid_sig']);
			$deliveries = null;

			if(array_key_exists('recipients',$i['notify']) && count($i['notify']['recipients'])) {
				logger('specific recipients');
				$recip_arr = array();
				foreach($i['notify']['recipients'] as $recip) {
					$recip_arr[] =  make_xchan_hash($recip['guid'],$recip['guid_sig']);
				}
				stringify_array_elms($recip_arr);
				$recips = implode(',',$recip_arr);
				$r = q("select channel_hash as hash from channel where channel_hash in ( " . $recips . " ) and not ( channel_pageflags & %d ) ",
					intval(PAGE_REMOVED)
				);
				if(! $r) {
					logger('recips: no recipients on this site');
					continue;
				}

				$deliveries = $r;

				// We found somebody on this site that's in the recipient list. 

			}
			else {
				if(($i['message']) && (array_key_exists('flags',$i['message'])) && (in_array('private',$i['message']['flags']))) {
					// This should not happen but until we can stop it...
					logger('private message was delivered with no recipients.');
					continue;
				}

				logger('public post');

				// Public post. look for any site members who are or may be accepting posts from this sender
				// and who are allowed to see them based on the sender's permissions

				$deliveries = allowed_public_recips($i);

			}

			// Go through the hash array and remove duplicates. array_unique() won't do this because the array is more than one level.

			$no_dups = array();
			if($deliveries) {
				foreach($deliveries as $d) {
					if(! in_array($d['hash'],$no_dups))
						$no_dups[] = $d['hash'];
				}

				if($no_dups) {
					$deliveries = array();
					foreach($no_dups as $n) {
						$deliveries[] = array('hash' => $n);
					}
				}
			}

			if(! $deliveries) {
				logger('zot_import: no deliveries on this site');
				continue;
			}
							
			if($i['message']) { 
				if($i['message']['type'] === 'activity') {
					$arr = get_item_elements($i['message']);

					if(! array_key_exists('created',$arr)) {
						logger('Activity rejected: probable failure to lookup author/owner. ' . print_r($i['message'],true));
						continue;
					}

					logger('Activity received: ' . print_r($arr,true), LOGGER_DATA);
					logger('Activity recipients: ' . print_r($deliveries,true), LOGGER_DATA);

					$relay = ((array_key_exists('flags',$i['message']) && in_array('relay',$i['message']['flags'])) ? true : false);
					$result = process_delivery($i['notify']['sender'],$arr,$deliveries,$relay);

				}
				elseif($i['message']['type'] === 'mail') {
					$arr = get_mail_elements($i['message']);

					logger('Mail received: ' . print_r($arr,true), LOGGER_DATA);
					logger('Mail recipients: ' . print_r($deliveries,true), LOGGER_DATA);


					$result = process_mail_delivery($i['notify']['sender'],$arr,$deliveries);

				}
				elseif($i['message']['type'] === 'profile') {
					$arr = get_profile_elements($i['message']);

					logger('Profile received: ' . print_r($arr,true), LOGGER_DATA);
					logger('Profile recipients: ' . print_r($deliveries,true), LOGGER_DATA);

					$result = process_profile_delivery($i['notify']['sender'],$arr,$deliveries);

				}
				elseif($i['message']['type'] === 'channel_sync') {
//					$arr = get_channelsync_elements($i['message']);

					$arr = $i['message'];

					logger('Channel sync received: ' . print_r($arr,true), LOGGER_DATA);
					logger('Channel sync recipients: ' . print_r($deliveries,true), LOGGER_DATA);
					
					$result = process_channel_sync_delivery($i['notify']['sender'],$arr,$deliveries);
				}
			}
			if($result){
				$return = array_merge($return,$result);
			}
		}
	}

	return $return;

}


// A public message with no listed recipients can be delivered to anybody who
// has PERMS_NETWORK for that type of post, or PERMS_SITE and is one the same
// site, or PERMS_SPECIFIC and the sender is a contact who is granted 
// permissions via their connection permissions in the address book.
// Here we take a given message and construct a list of hashes of everybody
// on the site that we should deliver to.  


function public_recips($msg) {

	$check_mentions = false;
	if($msg['message']['type'] === 'activity') {
		$col = 'channel_w_stream';
		$field = PERMS_W_STREAM;
		if(array_key_exists('flags',$msg['message']) && in_array('thread_parent', $msg['message']['flags'])) {
			// check mention recipient permissions on top level posts only
			$check_mentions = true;
		}
		else {
			// if this is a comment and it wasn't sent by the post owner, check to see who is allowing them to comment.
			// We should have one specific recipient and this step shouldn't be needed unless somebody stuffed up their software.
			// We may need this step to protect us from bad guys intentionally stuffing up their software.  
			// If it is sent by the post owner, we don't need to do this. We only need to see who is receiving the 
			// owner's stream (which was already set above) - as they control the comment permissions
			if($msg['notify']['sender']['guid_sig'] != $msg['message']['owner']['guid_sig']) {
				$col = 'channel_w_comment';
				$field = PERMS_W_COMMENT;
			}
		}
	}
	elseif($msg['message']['type'] === 'mail') {
		$col = 'channel_w_mail';
		$field = PERMS_W_MAIL;
	}

	if(! $col)
		return NULL;

	
	if($msg['notify']['sender']['url'] === z_root())
		$sql = " where (( " . $col . " & " . PERMS_NETWORK . " )  or ( " . $col . " & " . PERMS_SITE . " ) or ( " . $col . " & " . PERMS_PUBLIC . ")) ";				
	else
		$sql = " where (( " . $col . " & " . PERMS_NETWORK . " )  or ( "  . $col . " & " . PERMS_PUBLIC . ")) ";


	$r = q("select channel_hash as hash from channel $sql or channel_hash = '%s' ",
		dbesc($msg['notify']['sender']['hash'])
	);

	if(! $r)
		$r = array();

	$x = q("select channel_hash as hash from channel left join abook on abook_channel = channel_id where abook_xchan = '%s' and not ( channel_pageflags & " . PAGE_REMOVED . " ) and (( " . $col . " & " . PERMS_SPECIFIC . " )  and ( abook_my_perms & " . $field . " )) OR ( " . $col . " & " . PERMS_PENDING . " ) OR (( " . $col . " & " . PERMS_CONTACTS . " ) and not ( abook_flags & " . ABOOK_FLAG_PENDING . " )) ",
		dbesc($msg['notify']['sender']['hash'])
	); 

	if(! $x)
		$x = array();

	$r = array_merge($r,$x);

	// look for any public mentions on this site
	// They will get filtered by tgroup_check() so we don't need to check permissions now

	if($check_mentions && $msg['message']['tags']) {
		if(is_array($msg['message']['tags']) && $msg['message']['tags']) {
			foreach($msg['message']['tags'] as $tag) {
				if(($tag['type'] === 'mention') && (strpos($tag['url'],z_root()) !== false)) {
					$address = basename($tag['url']);
					if($address) {
						$z = q("select channel_hash as hash from channel where channel_address = '%s' limit 1",
							dbesc($address)
						);
						if($z)
							$r = array_merge($r,$z);
					}
				}
			}
		}
	}

	logger('public_recips: ' . print_r($r,true), LOGGER_DATA);
	return $r;
}

// This is the second part of the above function. We'll find all the channels willing to accept public posts from us,
// then match them against the sender privacy scope and see who in that list that the sender is allowing.

function allowed_public_recips($msg) {


	logger('allowed_public_recips: ' . print_r($msg,true));

	$recips = public_recips($msg);

	if(! $recips)
		return $recips;

	if($msg['message']['type'] === 'mail')
		return $recips;

	if(array_key_exists('public_scope',$msg['message']))
		$scope = $msg['message']['public_scope'];

	$hash = make_xchan_hash($msg['notify']['sender']['guid'],$msg['notify']['sender']['guid_sig']);

	if($scope === 'public' || $scope === 'network: red')
		return $recips;

	if(strpos($scope,'site:') === 0) {
		if(($scope === 'site: ' . get_app()->get_hostname()) && ($msg['notify']['sender']['url'] === z_root()))
			return $recips;
		else
			return array();
	}

	if($scope === 'self') {
		foreach($recips as $r)
			if($r['hash'] === $hash)
				return array('hash' => $hash);
	}

	if($scope === 'contacts') {
		$condensed_recips = array();
		foreach($recips as $rr)
			$condensed_recips[] = $rr['hash'];

		$results = array();
		$r = q("select channel_hash as hash from channel left join abook on abook_channel = channel_id where abook_xchan = '%s' and not ( channel_pageflags & %d ) ",
			dbesc($hash),
			intval(PAGE_REMOVED)
		);
		if($r) {
			foreach($r as $rr)
				if(in_array($rr['hash'],$condensed_recips))
					$results[] = array('hash' => $rr['hash']);
		}
		return $results;
	}

	return array();
}


function process_delivery($sender,$arr,$deliveries,$relay,$public = false) {

	$result = array();


	// We've validated the sender. Now make sure that the sender is the owner or author

	if(! $public) {
		if($sender['hash'] != $arr['owner_xchan'] && $sender['hash'] != $arr['author_xchan']) {
			logger("process_delivery: sender {$sender['hash']} is not owner {$arr['owner_xchan']} or author {$arr['author_xchan']} - mid {$arr['mid']}");
			return;
		}
	}
	
	foreach($deliveries as $d) {
		$r = q("select * from channel where channel_hash = '%s' limit 1",
			dbesc($d['hash'])
		);

		if(! $r) {
			$result[] = array($d['hash'],'recipients not found');
			continue;
		}

		$channel = $r[0];

		$tag_delivery = tgroup_check($channel['channel_id'],$arr);

		$perm = (($arr['mid'] == $arr['parent_mid']) ? 'send_stream' : 'post_comments');

		// This is our own post, possibly coming from a channel clone

		if($arr['owner_xchan'] == $d['hash']) {
			$arr['item_flags'] = $arr['item_flags'] | ITEM_WALL;
		}
		else {
			// clear the wall flag if it is set
			if($arr['item_flags'] & ITEM_WALL) {
				$arr['item_flags'] = ($arr['item_flags'] ^ ITEM_WALL);
			}
		}

		if((! perm_is_allowed($channel['channel_id'],$sender['hash'],$perm)) && (! $tag_delivery) && (! $public)) {
			logger("permission denied for delivery to channel {$channel['channel_id']} {$channel['channel_address']}");
			$result[] = array($d['hash'],'permission denied',$channel['channel_name'] . ' <' . $channel['channel_address'] . '@' . get_app()->get_hostname() . '>',$arr['mid']);
			continue;
		}
	
		if($arr['item_restrict'] & ITEM_DELETED) {

			// remove_community_tag is a no-op if this isn't a community tag activity
			remove_community_tag($sender,$arr,$channel['channel_id']);

			$item_id = delete_imported_item($sender,$arr,$channel['channel_id']);
			$result[] = array($d['hash'],(($item_id) ? 'deleted' : 'delete_failed'),$channel['channel_name'] . ' <' . $channel['channel_address'] . '@' . get_app()->get_hostname() . '>',$arr['mid']);

			if($relay && $item_id) {
				logger('process_delivery: invoking relay');
				proc_run('php','include/notifier.php','relay',intval($item_id));
				$result[] = array($d['hash'],'relayed',$channel['channel_name'] . ' <' . $channel['channel_address'] . '@' . get_app()->get_hostname() . '>',$arr['mid']);
			}

			continue;
		}

		$r = q("select id, edited from item where mid = '%s' and uid = %d limit 1",
			dbesc($arr['mid']),
			intval($channel['channel_id'])
		);
		if($r) {
			if($arr['edited'] > $r[0]['edited']) {
				$arr['id'] = $r[0]['id'];
				$arr['uid'] = $channel['channel_id'];
				update_imported_item($sender,$arr,$channel['channel_id']);
			}	
			$result[] = array($d['hash'],'updated',$channel['channel_name'] . ' <' . $channel['channel_address'] . '@' . get_app()->get_hostname() . '>',$arr['mid']);
			$item_id = $r[0]['id'];
		}
		else {
			$arr['aid'] = $channel['channel_account_id'];
			$arr['uid'] = $channel['channel_id'];
			$item_result = item_store($arr);
			$item_id = $item_result['item_id'];
			$parr = array('item_id' => $item_id,'item' => $arr,'sender' => $sender,'channel' => $channel);
			call_hooks('activity_received',$parr);

			add_source_route($item_id,$sender['hash']);

			$result[] = array($d['hash'],(($item_id) ? 'posted' : 'storage failed:' . $item_result['message']),$channel['channel_name'] . ' <' . $channel['channel_address'] . '@' . get_app()->get_hostname() . '>',$arr['mid']);
		}

		if($relay && $item_id) {
			logger('process_delivery: invoking relay');
			proc_run('php','include/notifier.php','relay',intval($item_id));
			$result[] = array($d['hash'],'relayed',$channel['channel_name'] . ' <' . $channel['channel_address'] . '@' . get_app()->get_hostname() . '>',$arr['mid']);
		}
	}

	if(! $deliveries)
		$result[] = array('','no recipients','',$arr['mid']);

	logger('process_delivery: local results: ' . print_r($result,true), LOGGER_DEBUG);

	return $result;
}


function remove_community_tag($sender,$arr,$uid) {

	if(! (activity_match($arr['verb'],ACTIVITY_TAG) && ($arr['obj_type'] == ACTIVITY_OBJ_TAGTERM)))
		return;

	logger('remove_community_tag: invoked');
 

	if(! get_pconfig($uid,'system','blocktags')) {
		logger('remove_community tag: permission denied.');
		return;
	}

	$r = q("select * from item where mid = '%s' and uid = %d limit 1",
		dbesc($arr['mid']),
		intval($uid)
	);
	if(! $r) {
		logger('remove_community_tag: no item');
		return;
	}

	if(($sender['hash'] != $r[0]['owner_xchan']) && ($sender['hash'] != $r[0]['author_xchan'])) {
		logger('remove_community_tag: sender not authorised.');
		return;
	}

	$i = $r[0];

	if($i['target'])
		$i['target'] = json_decode_plus($i['target']);
	if($i['object'])
		$i['object'] = json_decode_plus($i['object']);

	if(! ($i['target'] && $i['object'])) {
		logger('remove_community_tag: no target/object');
		return;
	}

	$message_id = $i['target']['id'];

	$r = q("select id from item where mid = '%s' and uid = %d limit 1",
		dbesc($message_id),
		intval($uid)
	);
	if(! $r) {
		logger('remove_community_tag: no parent message');
		return;
	}
	
	$x = q("delete from term where uid = %d and oid = %d and otype = %d and type = %d and term = '%s' and url = '%s' limit 1",
		intval($uid),
		intval($r[0]['id']),
		intval(TERM_OBJ_POST),
		intval(TERM_HASHTAG),
		dbesc($i['object']['title']),
		dbesc(get_rel_link($i['object']['link'],'alternate'))
	);

	return;
}

function update_imported_item($sender,$item,$uid) {

	$x = item_store_update($item);
	if(! $x['item_id'])
		logger('update_imported_item: failed: ' . $x['message']);
	else
		logger('update_imported_item');

}

function delete_imported_item($sender,$item,$uid) {

	logger('delete_imported_item invoked',LOGGER_DEBUG);

	$r = q("select id, item_restrict from item where ( author_xchan = '%s' or owner_xchan = '%s' or source_xchan = '%s' )
		and mid = '%s' and uid = %d limit 1",
		dbesc($sender['hash']),
		dbesc($sender['hash']),
		dbesc($sender['hash']),
		dbesc($item['mid']),
		intval($uid)
	);

	if(! $r) {
		logger('delete_imported_item: failed: ownership issue');
		return false;
	}

	if($r[0]['item_restrict'] & ITEM_DELETED) {
		logger('delete_imported_item: item was already deleted');
		return false;
	} 
		
	require_once('include/items.php');

	// FIXME issue #230 is related
	// Chicken/egg problem because we have to drop_item, but this removes information that tag_deliver may need to do its stuff.
	// We can't reverse the order because drop_item refuses to run if the item already has the deleted flag set and we need to
	// set that flag prior to calling tag_deliver.

	// Use phased deletion to set the deleted flag, call both tag_deliver and the notifier to notify downstream channels
	// and then clean up after ourselves with a cron job after several days to do the delete_item_lowlevel() (DROPITEM_PHASE2).

	drop_item($r[0]['id'],false, DROPITEM_PHASE1);

	tag_deliver($uid,$r[0]['id']);

	return $r[0]['id'];
}

function process_mail_delivery($sender,$arr,$deliveries) {


	$result = array();


	if($sender['hash'] != $arr['from_xchan']) {
		logger('process_mail_delivery: sender is not mail author');
		return;
	}


	
	foreach($deliveries as $d) {
		$r = q("select * from channel where channel_hash = '%s' limit 1",
			dbesc($d['hash'])
		);

		if(! $r) {
			$result[] = array($d['hash'],'not found');
			continue;
		}

		$channel = $r[0];

		if(! perm_is_allowed($channel['channel_id'],$sender['hash'],'post_mail')) {
			logger("permission denied for mail delivery {$channel['channel_id']}");
			$result[] = array($d['hash'],'permission denied',$channel['channel_name'],$arr['mid']);
			continue;
		}
	
		$r = q("select id from mail where mid = '%s' and channel_id = %d limit 1",
			dbesc($arr['mid']),
			intval($channel['channel_id'])
		);
		if($r) {
			if($arr['mail_flags'] & MAIL_RECALLED) {
				$x = q("delete from mail where id = %d and channel_id = %d limit 1",
					intval($r[0]['id']),
					intval($channel['channel_id'])
				);
				$result[] = array($d['hash'],'mail recalled',$channel['channel_name'],$arr['mid']);
				logger('mail_recalled');
			}
			else {				
				$result[] = array($d['hash'],'duplicate mail received',$channel['channel_name'],$arr['mid']);
				logger('duplicate mail received');
			}
			continue;
		}
		else {
			$arr['account_id'] = $channel['channel_account_id'];
			$arr['channel_id'] = $channel['channel_id'];
			$item_id = mail_store($arr);
			$result[] = array($d['hash'],'mail delivered',$channel['channel_name'],$arr['mid']);

		}
	}
	return $result;
}

function process_profile_delivery($sender,$arr,$deliveries) {

	// deliveries is irrelevant, what to do about birthday notification....?

	logger('process_profile_delivery', LOGGER_DEBUG);

	$r = q("select xchan_addr from xchan where xchan_hash = '%s' limit 1",
			dbesc($sender['hash'])
	);
	if($r)
		import_directory_profile($sender['hash'],$arr,$r[0]['xchan_addr'], UPDATE_FLAGS_UPDATED, 0);
}


/*
 * @function import_directory_profile
 * 
 * @returns boolean $updated if something changed
 *
 */

function import_directory_profile($hash,$profile,$addr,$ud_flags = UPDATE_FLAGS_UPDATED, $suppress_update = 0) {

	logger('import_directory_profile', LOGGER_DEBUG);
	if(! $hash)
		return false;

	$arr = array();

	$arr['xprof_hash']         = $hash;
	$arr['xprof_dob']          = datetime_convert('','',$profile['birthday'],'Y-m-d'); // !!!! check this for 0000 year
	$arr['xprof_age']          = (($profile['age'])         ? intval($profile['age']) : 0);
	$arr['xprof_desc']         = (($profile['description']) ? htmlspecialchars($profile['description'], ENT_COMPAT,'UTF-8',false) : '');
	$arr['xprof_gender']       = (($profile['gender'])      ? htmlspecialchars($profile['gender'],      ENT_COMPAT,'UTF-8',false) : '');
	$arr['xprof_marital']      = (($profile['marital'])     ? htmlspecialchars($profile['marital'],     ENT_COMPAT,'UTF-8',false) : '');
	$arr['xprof_sexual']       = (($profile['sexual'])      ? htmlspecialchars($profile['sexual'],      ENT_COMPAT,'UTF-8',false) : '');
	$arr['xprof_locale']       = (($profile['locale'])      ? htmlspecialchars($profile['locale'],      ENT_COMPAT,'UTF-8',false) : '');
	$arr['xprof_region']       = (($profile['region'])      ? htmlspecialchars($profile['region'],      ENT_COMPAT,'UTF-8',false) : '');
	$arr['xprof_postcode']     = (($profile['postcode'])    ? htmlspecialchars($profile['postcode'],    ENT_COMPAT,'UTF-8',false) : '');
	$arr['xprof_country']      = (($profile['country'])     ? htmlspecialchars($profile['country'],     ENT_COMPAT,'UTF-8',false) : '');
	$arr['xprof_about']        = (($profile['about'])       ? htmlspecialchars($profile['about'],       ENT_COMPAT,'UTF-8',false) : '');
	$arr['xprof_homepage']     = (($profile['homepage'])    ? htmlspecialchars($profile['homepage'],    ENT_COMPAT,'UTF-8',false) : '');
	$arr['xprof_hometown']     = (($profile['hometown'])    ? htmlspecialchars($profile['hometown'],    ENT_COMPAT,'UTF-8',false) : '');

	$clean = array();
	if(array_key_exists('keywords',$profile) and is_array($profile['keywords'])) {
		import_directory_keywords($hash,$profile['keywords']);
		foreach($profile['keywords'] as $kw) {
			$kw = trim(htmlspecialchars($kw,ENT_COMPAT,'UTF-8',false));
			$kw = trim($kw,',');
			$clean[] = $kw;
		}
	}

	$arr['xprof_keywords'] = implode(' ',$clean);

	// Self censored, make it so
	// These are not translated, so the German "erwachsenen" keyword will not censor the directory profile. Only the English form - "adult".   


	if(in_arrayi('nsfw',$clean) || in_arrayi('adult',$clean)) {
		q("update xchan set xchan_flags = (xchan_flags | %d) where xchan_hash = '%s' limit 1",
			intval(XCHAN_FLAGS_SELFCENSORED),
			dbesc($hash)
		);
	}


	$r = q("select * from xprof where xprof_hash = '%s' limit 1",
		dbesc($hash)
	);
	if($r) {
		$update = false;
		foreach($r[0] as $k => $v) {
			if((array_key_exists($k,$arr)) && ($arr[$k] != $v)) {
				logger('import_directory_profile: update' . $k . ' => ' . $arr[$k]);
				$update = true;
				break;
			}
		}
		if($update) {
			$x = q("update xprof set 
				xprof_desc = '%s', 
				xprof_dob = '%s', 
				xprof_age = %d,
				xprof_gender = '%s', 
				xprof_marital = '%s', 
				xprof_sexual = '%s', 
				xprof_locale = '%s', 
				xprof_region = '%s', 
				xprof_postcode = '%s', 
				xprof_country = '%s',
				xprof_about = '%s',
				xprof_homepage = '%s',
				xprof_hometown = '%s',
				xprof_keywords = '%s'
				where xprof_hash = '%s' limit 1",
				dbesc($arr['xprof_desc']),
				dbesc($arr['xprof_dob']),
				intval($arr['xprof_age']),
				dbesc($arr['xprof_gender']),
				dbesc($arr['xprof_marital']),
				dbesc($arr['xprof_sexual']),
				dbesc($arr['xprof_locale']),
				dbesc($arr['xprof_region']),
				dbesc($arr['xprof_postcode']),
				dbesc($arr['xprof_country']),
				dbesc($arr['xprof_about']),
				dbesc($arr['xprof_homepage']),
				dbesc($arr['xprof_hometown']),
				dbesc($arr['xprof_keywords']),
				dbesc($arr['xprof_hash'])
			);
		}
	}
	else {
		$update = true;
		logger('import_directory_profile: new profile');
		$x = q("insert into xprof (xprof_hash, xprof_desc, xprof_dob, xprof_age, xprof_gender, xprof_marital, xprof_sexual, xprof_locale, xprof_region, xprof_postcode, xprof_country, xprof_about, xprof_homepage, xprof_hometown, xprof_keywords) values ('%s', '%s', '%s', %d, '%s', '%s', '%s', '%s', '%s', '%s', '%s', '%s', '%s', '%s', '%s') ",
			dbesc($arr['xprof_hash']),
			dbesc($arr['xprof_desc']),
			dbesc($arr['xprof_dob']),
			intval($arr['xprof_age']),
			dbesc($arr['xprof_gender']),
			dbesc($arr['xprof_marital']),
			dbesc($arr['xprof_sexual']),
			dbesc($arr['xprof_locale']),
			dbesc($arr['xprof_region']),
			dbesc($arr['xprof_postcode']),
			dbesc($arr['xprof_country']),
			dbesc($arr['xprof_about']),
			dbesc($arr['xprof_homepage']),
			dbesc($arr['xprof_hometown']),
			dbesc($arr['xprof_keywords'])
		);
	}

	$d = array('xprof' => $arr, 'profile' => $profile, 'update' => $update);
	call_hooks('import_directory_profile', $d);

	if(($d['update']) && (! $suppress_update))
		update_modtime($arr['xprof_hash'],random_string() . '@' . get_app()->get_hostname(), $addr, $ud_flags);
	return $d['update'];
}

function import_directory_keywords($hash,$keywords) {

	$existing = array();
	$r = q("select * from xtag where xtag_hash = '%s'",
		dbesc($hash)
	);

	if($r) {
		foreach($r as $rr)
			$existing[] = $rr['xtag_term'];
	}

	$clean = array();
	foreach($keywords as $kw) {
		$kw = trim(htmlspecialchars($kw,ENT_COMPAT,'UTF-8',false));
		$kw = trim($kw,',');
		$clean[] = $kw;
	}

	foreach($existing as $x) {
		if(! in_array($x,$clean))
			$r = q("delete from xtag where xtag_hash = '%s' and xtag_term = '%s' limit 1",
				dbesc($hash),
				dbesc($x)
			);
	}
	foreach($clean as $x) {
		if(! in_array($x,$existing))
			$r = q("insert into xtag ( xtag_hash, xtag_term) values ( '%s' ,'%s' )",
				dbesc($hash),
				dbesc($x)
			);
	}
}


function update_modtime($hash,$guid,$addr,$flags = 0) {

	$dirmode = intval(get_config('system','directory_mode'));

	if($dirmode == DIRECTORY_MODE_NORMAL)
		return;

	if($flags) {
		q("insert into updates (ud_hash, ud_guid, ud_date, ud_flags, ud_addr ) values ( '%s', '%s', '%s', %d, '%s' )",
			dbesc($hash),
			dbesc($guid),
			dbesc(datetime_convert()),
			intval($flags),
			dbesc($addr)
		);
	}
	else {
		q("update updates set ud_flags = ( ud_flags | %d ) where ud_addr = '%s' and not (ud_flags & %d) ",
			intval(UPDATE_FLAGS_UPDATED),
			dbesc($addr),
			intval(UPDATE_FLAGS_UPDATED)
		);
	}
}


function import_site($arr,$pubkey) {
	if( (! is_array($arr)) || (! $arr['url']) || (! $arr['url_sig']))
		return false;

	if(! rsa_verify($arr['url'],base64url_decode($arr['url_sig']),$pubkey)) {
		logger('import_site: bad url_sig');
		return false;
	}

	$update = false;
	$exists = false;

	$r = q("select * from site where site_url = '%s' limit 1",
		dbesc($arr['url'])
	);
	if($r) {
		$exists = true;
		$siterecord = $r[0];
	}

	$site_directory = 0;
	if($arr['directory_mode'] == 'normal')
		$site_directory = DIRECTORY_MODE_NORMAL;

	if($arr['directory_mode'] == 'primary')
		$site_directory = DIRECTORY_MODE_PRIMARY;
	if($arr['directory_mode'] == 'secondary')
		$site_directory = DIRECTORY_MODE_SECONDARY;
	if($arr['directory_mode'] == 'standalone')
		$site_directory = DIRECTORY_MODE_STANDALONE;

	$register_policy = 0;
	if($arr['register_policy'] == 'closed')
		$register_policy = REGISTER_CLOSED;
	if($arr['register_policy'] == 'open')
		$register_policy = REGISTER_OPEN;
	if($arr['register_policy'] == 'approve')
		$register_policy = REGISTER_APPROVE;

	$access_policy = 0;
	if(array_key_exists('access_policy',$arr)) {
		if($arr['access_policy'] === 'private')
			$access_policy = ACCESS_PRIVATE;
		if($arr['access_policy'] === 'paid')
			$access_policy = ACCESS_PAID;
		if($arr['access_policy'] === 'free')
			$access_policy = ACCESS_FREE;
		if($arr['access_policy'] === 'tiered')
			$access_policy = ACCESS_TIERED;
	}

	// don't let insecure sites register as public hubs

	if(strpos($arr['url'],'https://') === false)
		$access_policy = ACCESS_PRIVATE;

	if($access_policy != ACCESS_PRIVATE) {
		$x = z_fetch_url($arr['url'] . '/siteinfo/json');
		if(! $x['success'])
			$access_policy = ACCESS_PRIVATE;
	}
	
	$directory_url = htmlspecialchars($arr['directory_url'],ENT_COMPAT,'UTF-8',false);
	$url = htmlspecialchars($arr['url'],ENT_COMPAT,'UTF-8',false);
	$sellpage = htmlspecialchars($arr['sellpage'],ENT_COMPAT,'UTF-8',false);
	$site_location = htmlspecialchars($arr['location'],ENT_COMPAT,'UTF-8',false);

	if($exists) {
		if(($siterecord['site_flags'] != $site_directory)
			|| ($siterecord['site_access'] != $access_policy)
			|| ($siterecord['site_directory'] != $directory_url)
			|| ($siterecord['site_sellpage'] != $sellpage)
			|| ($siterecord['site_location'] != $site_location)
			|| ($siterecord['site_register'] != $register_policy)) {
			$update = true;

//			logger('import_site: input: ' . print_r($arr,true));
//			logger('import_site: stored: ' . print_r($siterecord,true));

			$r = q("update site set site_location = '%s', site_flags = %d, site_access = %d, site_directory = '%s', site_register = %d, site_update = '%s', site_sellpage = '%s'
				where site_url = '%s' limit 1",
				dbesc($site_location),
				intval($site_directory),
				intval($access_policy),
				dbesc($directory_url),
				intval($register_policy),
				dbesc(datetime_convert()),
				dbesc($sellpage),
				dbesc($url)
			);
			if(! $r) {
				logger('import_site: update failed. ' . print_r($arr,true));
			}
		}
	}
	else {
		$update = true;
		$r = q("insert into site ( site_location, site_url, site_access, site_flags, site_update, site_directory, site_register, site_sellpage )
			values ( '%s', '%s', %d, %d, '%s', '%s', %d, '%s' )",
			dbesc($site_location),
			dbesc($url),
			intval($access_policy),
			intval($site_directory),
			dbesc(datetime_convert()),
			dbesc($directory_url),
			intval($register_policy),
			dbesc($sellpage)
		);
		if(! $r) {
			logger('import_site: record create failed. ' . print_r($arr,true));
		}
	}

	return $update;

}



/**
 * Send a zot packet to all hubs where this channel is duplicated, refreshing
 * such things as personal settings, channel permissions, address book updates, etc.
 */

function build_sync_packet($uid = 0, $packet = null, $groups_changed = false) {

	$a = get_app();

	logger('build_sync_packet');

	if(! $uid)
		$uid = local_user();

	if(! $uid)
		return;

	$r = q("select * from channel where channel_id = %d limit 1",
		intval($uid)
	);
	if(! $r)
		return;

	$channel = $r[0];

	$h = q("select * from hubloc where hubloc_hash = '%s'",
		dbesc($channel['channel_hash'])
	);

	if(! $h)
		return;

	$synchubs = array();

	foreach($h as $x) {
		if($x['hubloc_host'] == $a->get_hostname())
			continue;
		$synchubs[] = $x;
	}

	if(! $synchubs)
		return;

	$r = q("select xchan_guid, xchan_guid_sig from xchan where xchan_hash  = '%s' limit 1",
		dbesc($channel['channel_hash'])
	);
	if(! $r)
		return;

	$env_recips = array();
	$env_recips[] = array('guid' => $r[0]['xchan_guid'],'guid_sig' => $r[0]['xchan_guid_sig']);

	$info = (($packet) ? $packet : array());
	$info['type'] = 'channel_sync';

	if(array_key_exists($uid,$a->config) && array_key_exists('transient',$a->config[$uid])) {
		$settings = $a->config[$uid]['transient'];
		if($settings) {
			$info['config'] = $settings;
		}
	}
	
	if($channel) {
		$info['channel'] = array();
		foreach($channel as $k => $v) {

			// filter out any joined tables like xchan

			if(strpos($k,'channel_') !== 0)
				continue;

			// don't pass these elements, they should not be synchronised

			$disallowed = array('channel_id','channel_account_id','channel_primary','channel_prvkey','channel_address');

			if(in_array($k,$disallowed))
				continue;

			$info['channel'][$k] = $v;
		}
	}

	if($groups_changed) {
		$r = q("select hash as collection, visible, deleted, name from groups where uid = %d",
			intval($uid)
		);
		if($r)
			$info['collections'] = $r;
		$r = q("select groups.hash as collection, group_member.xchan as member from groups left join group_member on groups.id = group_member.gid where group_member.uid = %d",
			intval($uid)
		);
		if($r)
			$info['collection_members'] = $r;
			
	}

	$interval = ((get_config('system','delivery_interval') !== false) 
			? intval(get_config('system','delivery_interval')) : 2 );


	logger('build_sync_packet: packet: ' . print_r($info,true), LOGGER_DATA);

	foreach($synchubs as $hub) {
		$hash = random_string();
		$n = zot_build_packet($channel,'notify',$env_recips,$hub['hubloc_sitekey'],$hash);
		q("insert into outq ( outq_hash, outq_account, outq_channel, outq_driver, outq_posturl, outq_async, outq_created, outq_updated, outq_notify, outq_msg ) values ( '%s', %d, %d, '%s', '%s', %d, '%s', '%s', '%s', '%s' )",
			dbesc($hash),
			intval($channel['channel_account']),
			intval($channel['channel_id']),
			dbesc('zot'),
			dbesc($hub['hubloc_callback']),
			intval(1),
			dbesc(datetime_convert()),
			dbesc(datetime_convert()),
			dbesc($n),
			dbesc(json_encode($info))
		);

		proc_run('php','include/deliver.php',$hash);
		if($interval)
			@time_sleep_until(microtime(true) + (float) $interval);
	}


}

function process_channel_sync_delivery($sender,$arr,$deliveries) {

// FIXME - this will sync red structures (channel, pconfig and abook). Eventually we need to make this application agnostic.
// TODO: missing group membership changes

	$result = array();
	
	foreach($deliveries as $d) {
		$r = q("select * from channel where channel_hash = '%s' limit 1",
			dbesc($d['hash'])
		);

		if(! $r) {
			$result[] = array($d['hash'],'not found');
			continue;
		}

		$channel = $r[0];

		if($channel['channel_hash'] != $sender['hash']) {
			logger('process_channel_sync_delivery: possible forgery. Sender ' . $sender['hash'] . ' is not ' . $channel['channel_hash']);
			$result[] = array($d['hash'],'channel mismatch',$channel['channel_name'],'');
			continue;
		}

		if(array_key_exists('config',$arr) && is_array($arr['config']) && count($arr['config'])) {
			foreach($arr['config'] as $cat => $k) {
				foreach($arr['config'][$cat] as $k => $v)
					set_pconfig($channel['channel_id'],$cat,$k,$v);
			}
		}

		if(array_key_exists('channel',$arr) && is_array($arr['channel']) && count($arr['channel'])) {
			$disallowed = array('channel_id','channel_account_id','channel_primary','channel_prvkey', 'channel_address', 'channel_notifyflags');

			$clean = array();
			foreach($arr['channel'] as $k => $v) {
				if(in_array($k,$disallowed))
					continue;
				$clean[$k] = $v;
			}
			if(count($clean)) {
				foreach($clean as $k => $v) {
					$r = dbq("UPDATE channel set " . dbesc($k) . " = '" . dbesc($v) 
						. "' where channel_id = " . intval($channel['channel_id']) . " limit 1");
				}
			}
		}



		if(array_key_exists('abook',$arr) && is_array($arr['abook']) && count($arr['abook'])) {

			$disallowed = array('abook_id','abook_account','abook_channel');

			$clean = array();
			foreach($arr['abook'] as $abook) {

				// Perform discovery if the referenced xchan hasn't ever been seen on this hub.
				// This relies on the undocumented behaviour that red sites send xchan info with the abook

				if($abook['abook_xchan'] && $abook['xchan_address']) {
					$h = zot_get_hublocs($abook['abook_xchan']);
					if(! $h) {
						$f = zot_finger($abook['xchan_address'],$channel);
						if(! $f['success']) {
							logger('process_channel_sync_delivery: abook not probe-able' . $abook['xchan_address']);
							continue;
						}
						$j = json_decode($f['body'],true);
				        if(! ($j['success'] && $j['guid'])) {
							logger('process_channel_sync_delivery: probe failed.');
							continue;
						}

						$x = import_xchan($j);

						if(! $x['success']) {
							logger('process_channel_sync_delivery: import failed.');
							continue;
						}
					}
				}

				foreach($abook as $k => $v) {
					if(in_array($k,$disallowed) || (strpos($k,'abook') !== 0))
						continue;
					$clean[$k] = $v;
				}

				if(! array_key_exists('abook_xchan',$clean))
					continue;

				$r = q("select * from abook where abook_xchan = '%s' and abook_channel = %d limit 1",
					dbesc($clean['abook_xchan']),
					intval($channel['channel_id'])
				);

				// make sure we have an abook entry for this xchan on this system

				if(! $r) {
					q("insert into abook ( abook_xchan, abook_channel ) values ('%s', %d ) ",
						dbesc($clean['abook_xchan']),
						intval($channel['channel_id'])
					);
				} 

				if(count($clean)) {
					foreach($clean as $k => $v) {
						$r = dbq("UPDATE abook set " . dbesc($k) . " = '" . dbesc($v) 
						. "' where abook_xchan = '" . dbesc($clean['abook_xchan']) . "' and abook_channel = " . intval($channel['channel_id']) 
						. " limit 1");
					}
				}
			}
		}

		// sync collections (privacy groups) oh joy...

		if(array_key_exists('collections',$arr) && is_array($arr['collections']) && count($arr['collections'])) {
			$x = q("select * from groups where uid = %d",
				intval($channel['channel_id'])
			);
			foreach($arr['collections'] as $cl) {
				$found = false;
				if($x) {
					foreach($x as $y) {
						if($cl['collection'] == $y['hash']) {
							$found = true;
							break;
						}
					}
					if($found) {
						if(($y['name'] != $cl['name']) 
							|| ($y['visible'] != $cl['visible']) 
							|| ($y['deleted'] != $cl['deleted'])) {
							q("update groups set name = '%s', visible = %d, deleted = %d where hash = '%s' and uid = %d limit 1",
								dbesc($cl['name']),
								intval($cl['visible']),
								intval($cl['deleted']),
								dbesc($cl['hash']),
								intval($channel['channel_id'])
							);
						}
						if(intval($cl['deleted']) && (! intval($y['deleted']))) {
							q("delete from group_member where gid = %d",
								intval($y['id'])
							);  
						}
					}
				}
				if(! $found) {
					$r = q("INSERT INTO `groups` ( hash, uid, visible, deleted, name )
						VALUES( '%s', %d, %d, %d, '%s' ) ",
						dbesc($cl['collection']),
						intval($channel['channel_id']),
						intval($cl['visible']),
						intval($cl['deleted']),
           				dbesc($cl['name'])
       				);
				}

				// now look for any collections locally which weren't in the list we just received.
				// They need to be removed by marking deleted and removing the members.
				// This shouldn't happen except for clones created before this function was written.

				if($x) {
					$found_local = false;
					foreach($x as $y) {
						foreach($arr['collections'] as $cl) {
							if($cl['collection'] == $y['hash']) {
								$found_local = true;
								break;
							}
						}
						if(! $found_local) {			
							q("delete from group_member where gid = %d",
								intval($y['id'])
							);  
							q("update groups set deleted = 1 where id = %d and uid = %d limit 1",
								intval($y['id']),
								intval($channel['channel_id'])
							);
						}
					}
				}
			}

			// reload the group list with any updates
			$x = q("select * from groups where uid = %d",
				intval($channel['channel_id'])
			);

			// now sync the members

			if(array_key_exists('collection_members',$arr) && 
				is_array($arr['collection_members']) && count($arr['collection_members'])) {

				// first sort into groups keyed by the group hash
				$members = array();
				foreach($arr['collection_members'] as $cm) {
					if(! array_key_exists($cm['collection'],$members))
						$members[$cm['collection']] = array();
					$members[$cm['collection']][] = $cm['member'];	
				}

				// our group list is already synchronised
				if($x) {
					foreach($x as $y) {

						// for each group, loop on members list we just received
						foreach($members[$y['hash']] as $member) {
							$found = false;
							$z = q("select xchan from group_member where gid = %d and uid = %d and xchan = '%s' limit 1",
								intval($y['id']),
								intval($channel['channel_id']),
								dbesc($member)
							);
							if($z)
								$found = true;

							// if somebody is in the group that wasn't before - add them

							if(! $found) {
								q("INSERT INTO `group_member` (`uid`, `gid`, `xchan`)
									VALUES( %d, %d, '%s' ) ",
									intval($channel['channel_id']),
									intval($y['id']),
									dbesc($member)
								);
							}
						}

						// now retrieve a list of members we have on this site
						$m = q("select xchan from group_member where gid = %d and uid = %d",
							intval($y['id']),
							intval($channel['channel_id'])
						);
						if($m) {
							foreach($m as $mm) {
								// if the local existing member isn't in the list we just received - remove them
								if(! in_array($mm['xchan'],$members[$y['hash']])) {
									q("delete from group_member where xchan = '%s' and gid = %d and uid = %d limit 1",
										dbesc($mm['xchan']),
										intval($y['id']),
										intval($channel['channel_id'])
									);
								}
							}
						}
					}
				}
			}
		}

		if(array_key_exists('profile',$arr) && is_array($arr['profile']) && count($arr['profile'])) {

			$disallowed = array('id','aid','uid');

			foreach($arr['profile'] as $profile) {
				$x = q("select * from profile where profile_guid = '%s' and uid = %d limit 1",
					dbesc($profile['profile_guid']),
					intval($channel['channel_id'])
				);
				if(! $x) {
					q("insert into profile ( profile_guid, aid, uid ) values ('%s', %d, %d)",
						dbesc($profile['profile_guid']),
						intval($channel['channel_account_id']),		
						intval($channel['channel_id'])
					);
					$x = q("select * from profile where profile_guid = '%s' and uid = %d limit 1",
						dbesc($profile['profile_guid']),
						intval($channel['channel_id'])
					);
					if(! $x)
						continue;
				}
				$clean = array();
				foreach($profile as $k => $v) {
					if(in_array($k,$disallowed))
						continue;
					$clean[$k] = $v;
					// TODO - check if these are allowed, otherwise we'll error
					// We also need to import local photos if a custom photo is selected
				}
				if(count($clean)) {
					foreach($clean as $k => $v) {
						$r = dbq("UPDATE profile set " . dbesc($k) . " = '" . dbesc($v) 
						. "' where profile_guid = '" . dbesc($profile['profile_guid']) . "' and uid = " . intval($channel['channel_id']) 
						. " limit 1");
					}
				}
			}
		}
		
		$result[] = array($d['hash'],'channel sync updated',$channel['channel_name'],'');


	}
	return $result;
}

// We probably should make rpost discoverable.
 
function get_rpost_path($observer) {
	if(! $observer)
		return '';
	$parsed = parse_url($observer['xchan_url']);
	return $parsed['scheme'] . '://' . $parsed['host'] . (($parsed['port']) ? ':' . $parsed['port'] : '') . '/rpost?f=';

}

function import_author_zot($x) {
	$hash = make_xchan_hash($x['guid'],$x['guid_sig']);
	$r = q("select hubloc_url from hubloc where hubloc_guid = '%s' and hubloc_guid_sig = '%s' and (hubloc_flags & %d) limit 1",
		dbesc($x['guid']),
		dbesc($x['guid_sig']),
		intval(HUBLOC_FLAGS_PRIMARY)
	);

	if($r) {
		logger('import_author_zot: in cache', LOGGER_DEBUG);
		return $hash;
	}

	logger('import_author_zot: entry not in cache - probing: ' . print_r($x,true), LOGGER_DEBUG);
	
	$them = array('hubloc_url' => $x['url'],'xchan_guid' => $x['guid'], 'xchan_guid_sig' => $x['guid_sig']);
	if(zot_refresh($them))
		return $hash;
	return false;
}