summaryrefslogtreecommitdiff
path: root/includes/Title.php
blob: 74d78ba5919e5f6da870d8a0e3897c78b3a1136c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
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
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944
2945
2946
2947
2948
2949
2950
2951
2952
2953
2954
2955
2956
2957
2958
2959
2960
2961
2962
2963
2964
2965
2966
2967
2968
2969
2970
2971
2972
2973
2974
2975
2976
2977
2978
2979
2980
2981
2982
2983
2984
2985
2986
2987
2988
2989
2990
2991
2992
2993
2994
2995
2996
2997
2998
2999
3000
3001
3002
3003
3004
3005
3006
3007
3008
3009
3010
3011
3012
3013
3014
3015
3016
3017
3018
3019
3020
3021
3022
3023
3024
3025
3026
3027
3028
3029
3030
3031
3032
3033
3034
3035
3036
3037
3038
3039
3040
3041
3042
3043
3044
3045
3046
3047
3048
3049
3050
3051
3052
3053
3054
3055
3056
3057
3058
3059
3060
3061
3062
3063
3064
3065
3066
3067
3068
3069
3070
3071
3072
3073
3074
3075
3076
3077
3078
3079
3080
3081
3082
3083
3084
3085
3086
3087
3088
3089
3090
3091
3092
3093
3094
3095
3096
3097
3098
3099
3100
3101
3102
3103
3104
3105
3106
3107
3108
3109
3110
3111
3112
3113
3114
3115
3116
3117
3118
3119
3120
3121
3122
3123
3124
3125
3126
3127
3128
3129
3130
3131
3132
3133
3134
3135
3136
3137
3138
3139
3140
3141
3142
3143
3144
3145
3146
3147
3148
3149
3150
3151
3152
3153
3154
3155
3156
3157
3158
3159
3160
3161
3162
3163
3164
3165
3166
3167
3168
3169
3170
3171
3172
3173
3174
3175
3176
3177
3178
3179
3180
3181
3182
3183
3184
3185
3186
3187
3188
3189
3190
3191
3192
3193
3194
3195
3196
3197
3198
3199
3200
3201
3202
3203
3204
3205
3206
3207
3208
3209
3210
3211
3212
3213
3214
3215
3216
3217
3218
3219
3220
3221
3222
3223
3224
3225
3226
3227
3228
3229
3230
3231
3232
3233
3234
3235
3236
3237
3238
3239
3240
3241
3242
3243
3244
3245
3246
3247
3248
3249
3250
3251
3252
3253
3254
3255
3256
3257
3258
3259
3260
3261
3262
3263
3264
3265
3266
3267
3268
3269
3270
3271
3272
3273
3274
3275
3276
3277
3278
3279
3280
3281
3282
3283
3284
3285
3286
3287
3288
3289
3290
3291
3292
3293
3294
3295
3296
3297
3298
3299
3300
3301
3302
3303
3304
3305
3306
3307
3308
3309
3310
3311
3312
3313
3314
3315
3316
3317
3318
3319
3320
3321
3322
3323
3324
3325
3326
3327
3328
3329
3330
3331
3332
3333
3334
3335
3336
3337
3338
3339
3340
3341
3342
3343
3344
3345
3346
3347
3348
3349
3350
3351
3352
3353
3354
3355
3356
3357
3358
3359
3360
3361
3362
3363
3364
3365
3366
3367
3368
3369
3370
3371
3372
3373
3374
3375
3376
3377
3378
3379
3380
3381
3382
3383
3384
3385
3386
3387
3388
3389
3390
3391
3392
3393
3394
3395
3396
3397
3398
3399
3400
3401
3402
3403
3404
3405
3406
3407
3408
3409
3410
3411
3412
3413
3414
3415
3416
3417
3418
3419
3420
3421
3422
3423
3424
3425
3426
3427
3428
3429
3430
3431
3432
3433
3434
3435
3436
3437
3438
3439
3440
3441
3442
3443
3444
3445
3446
3447
3448
3449
3450
3451
3452
3453
3454
3455
3456
3457
3458
3459
3460
3461
3462
3463
3464
3465
3466
3467
3468
3469
3470
3471
3472
3473
3474
3475
3476
3477
3478
3479
3480
3481
3482
3483
3484
3485
3486
3487
3488
3489
3490
3491
3492
3493
3494
3495
3496
3497
3498
3499
3500
3501
3502
3503
3504
3505
3506
3507
3508
3509
3510
3511
3512
3513
3514
3515
3516
3517
3518
3519
3520
3521
3522
3523
3524
3525
3526
3527
3528
3529
3530
3531
3532
3533
3534
3535
3536
3537
3538
3539
3540
3541
3542
3543
3544
3545
3546
3547
3548
3549
3550
3551
3552
3553
3554
3555
3556
3557
3558
3559
3560
3561
3562
3563
3564
3565
3566
3567
3568
3569
3570
3571
3572
3573
3574
3575
3576
3577
3578
3579
3580
3581
3582
3583
3584
3585
3586
3587
3588
3589
3590
3591
3592
3593
3594
3595
3596
3597
3598
3599
3600
3601
3602
3603
3604
3605
3606
3607
3608
3609
3610
3611
3612
3613
3614
3615
3616
3617
3618
3619
3620
3621
3622
3623
3624
3625
3626
3627
3628
3629
3630
3631
3632
3633
3634
3635
3636
3637
3638
3639
3640
3641
3642
3643
3644
3645
3646
3647
3648
3649
3650
3651
3652
3653
3654
3655
3656
3657
3658
3659
3660
3661
3662
3663
3664
3665
3666
3667
3668
3669
3670
3671
3672
3673
3674
3675
3676
3677
3678
3679
3680
3681
3682
3683
3684
3685
3686
3687
3688
3689
3690
3691
3692
3693
3694
3695
3696
3697
3698
3699
3700
3701
3702
3703
3704
3705
3706
3707
3708
3709
3710
3711
3712
3713
3714
3715
3716
3717
3718
3719
3720
3721
3722
3723
3724
3725
3726
3727
3728
3729
3730
3731
3732
3733
3734
3735
3736
3737
3738
3739
3740
3741
3742
3743
3744
3745
3746
3747
3748
3749
3750
3751
3752
3753
3754
3755
3756
3757
3758
3759
3760
3761
3762
3763
3764
3765
3766
3767
3768
3769
3770
3771
3772
3773
3774
3775
3776
3777
3778
3779
3780
3781
3782
3783
3784
3785
3786
3787
3788
3789
3790
3791
3792
3793
3794
3795
3796
3797
3798
3799
3800
3801
3802
3803
3804
3805
3806
3807
3808
3809
3810
3811
3812
3813
3814
3815
3816
3817
3818
3819
3820
3821
3822
3823
3824
3825
3826
3827
3828
3829
3830
3831
3832
3833
3834
3835
3836
3837
3838
3839
3840
3841
3842
3843
3844
3845
3846
3847
3848
3849
3850
3851
3852
3853
3854
3855
3856
3857
3858
3859
3860
3861
3862
3863
3864
3865
3866
3867
3868
3869
3870
3871
3872
3873
3874
3875
3876
3877
3878
3879
3880
3881
3882
3883
3884
3885
3886
3887
3888
3889
3890
3891
3892
3893
3894
3895
3896
3897
3898
3899
3900
3901
3902
3903
3904
3905
3906
3907
3908
3909
3910
3911
3912
3913
3914
3915
3916
3917
3918
3919
3920
3921
3922
3923
3924
3925
3926
3927
3928
3929
3930
3931
3932
3933
3934
3935
3936
3937
3938
3939
3940
3941
3942
3943
3944
3945
3946
3947
3948
3949
3950
3951
3952
3953
3954
3955
3956
3957
3958
3959
3960
3961
3962
3963
3964
3965
3966
3967
3968
3969
3970
3971
3972
3973
3974
3975
3976
3977
3978
3979
3980
3981
3982
3983
3984
3985
3986
3987
3988
3989
3990
3991
3992
3993
3994
3995
3996
3997
3998
3999
4000
4001
4002
4003
4004
4005
4006
4007
4008
4009
4010
4011
4012
4013
4014
4015
4016
4017
4018
4019
4020
4021
4022
4023
4024
4025
4026
4027
4028
4029
4030
4031
4032
4033
4034
4035
4036
4037
4038
4039
4040
4041
4042
4043
4044
4045
4046
4047
4048
4049
4050
4051
4052
4053
4054
4055
4056
4057
4058
4059
4060
4061
4062
4063
4064
4065
4066
4067
4068
4069
4070
4071
4072
4073
4074
4075
4076
4077
4078
4079
4080
4081
4082
4083
4084
4085
4086
4087
4088
4089
4090
4091
4092
4093
4094
4095
4096
4097
4098
4099
4100
4101
4102
4103
4104
4105
4106
4107
4108
4109
4110
4111
4112
4113
4114
4115
4116
4117
4118
4119
4120
4121
4122
4123
4124
4125
4126
4127
4128
4129
4130
4131
4132
4133
4134
4135
4136
4137
4138
4139
4140
4141
4142
4143
4144
4145
4146
4147
4148
4149
4150
4151
4152
4153
4154
4155
4156
4157
4158
4159
4160
4161
4162
4163
4164
4165
4166
4167
4168
4169
4170
4171
4172
4173
4174
4175
4176
4177
4178
4179
4180
4181
4182
4183
4184
4185
4186
4187
4188
4189
4190
4191
4192
4193
4194
4195
4196
4197
4198
4199
4200
4201
4202
4203
4204
4205
4206
4207
4208
4209
4210
4211
4212
4213
4214
4215
4216
4217
4218
4219
4220
4221
4222
4223
4224
4225
4226
4227
4228
4229
4230
4231
4232
4233
4234
4235
4236
4237
4238
4239
4240
4241
4242
4243
4244
4245
4246
4247
4248
4249
4250
4251
4252
4253
4254
4255
4256
4257
4258
4259
4260
4261
4262
4263
4264
4265
4266
4267
4268
4269
4270
4271
4272
4273
4274
4275
4276
4277
4278
4279
4280
4281
4282
4283
4284
4285
4286
4287
4288
4289
4290
4291
4292
4293
4294
4295
4296
4297
4298
4299
4300
4301
4302
4303
4304
4305
4306
4307
4308
4309
4310
4311
4312
4313
4314
4315
4316
4317
4318
4319
4320
4321
4322
4323
4324
4325
4326
4327
4328
4329
4330
4331
4332
4333
4334
4335
4336
4337
4338
4339
4340
4341
4342
4343
4344
4345
4346
4347
4348
4349
4350
4351
4352
4353
4354
4355
4356
4357
4358
4359
4360
4361
4362
4363
4364
4365
4366
4367
4368
4369
4370
4371
4372
4373
4374
4375
4376
4377
4378
4379
4380
4381
4382
4383
4384
4385
4386
4387
4388
4389
4390
4391
4392
4393
4394
4395
4396
4397
4398
4399
4400
4401
4402
4403
4404
4405
4406
4407
4408
4409
4410
4411
4412
4413
4414
4415
4416
4417
4418
4419
4420
4421
4422
4423
4424
4425
4426
4427
4428
4429
4430
4431
4432
4433
4434
4435
4436
4437
4438
4439
4440
4441
4442
4443
4444
4445
4446
4447
4448
4449
4450
4451
4452
4453
4454
4455
4456
4457
4458
4459
4460
4461
4462
4463
4464
4465
4466
4467
4468
4469
4470
4471
4472
4473
4474
4475
4476
4477
4478
4479
4480
4481
4482
4483
4484
4485
4486
4487
4488
4489
4490
4491
4492
4493
4494
4495
4496
4497
4498
4499
4500
4501
4502
4503
4504
4505
4506
4507
4508
4509
4510
4511
4512
4513
4514
4515
4516
4517
4518
4519
4520
4521
4522
4523
4524
4525
4526
4527
4528
4529
4530
4531
4532
4533
4534
4535
4536
4537
4538
4539
4540
4541
4542
4543
4544
4545
4546
4547
4548
4549
4550
4551
4552
4553
4554
4555
4556
4557
4558
4559
4560
4561
4562
4563
4564
4565
4566
4567
4568
4569
4570
4571
4572
4573
4574
4575
4576
4577
4578
4579
4580
4581
4582
4583
4584
4585
4586
4587
4588
4589
4590
4591
4592
4593
4594
4595
4596
4597
4598
4599
4600
4601
4602
4603
4604
4605
4606
4607
4608
4609
4610
4611
4612
4613
4614
4615
4616
4617
4618
4619
4620
4621
4622
4623
4624
4625
4626
4627
4628
4629
4630
4631
4632
4633
4634
4635
4636
4637
4638
4639
4640
4641
4642
4643
4644
4645
4646
4647
4648
4649
4650
4651
4652
4653
4654
4655
4656
4657
4658
4659
4660
4661
4662
4663
4664
4665
4666
4667
4668
4669
4670
4671
4672
4673
4674
4675
4676
4677
4678
4679
4680
4681
4682
4683
4684
4685
4686
4687
4688
4689
4690
4691
4692
4693
4694
4695
4696
4697
4698
4699
4700
4701
4702
4703
4704
4705
4706
4707
4708
4709
4710
4711
4712
4713
4714
4715
4716
4717
4718
4719
4720
4721
4722
4723
4724
4725
4726
4727
4728
4729
4730
4731
4732
4733
4734
4735
4736
4737
4738
4739
4740
4741
4742
4743
4744
4745
4746
4747
4748
4749
4750
4751
4752
4753
4754
4755
4756
4757
4758
4759
4760
4761
4762
4763
4764
4765
4766
4767
4768
4769
4770
4771
4772
4773
4774
4775
4776
4777
4778
4779
4780
4781
4782
4783
4784
4785
4786
4787
4788
4789
4790
4791
4792
4793
4794
4795
4796
4797
4798
4799
4800
4801
4802
4803
4804
4805
4806
4807
4808
4809
4810
4811
4812
4813
4814
4815
4816
4817
<?php
/**
 * Representation of a title within %MediaWiki.
 *
 * See title.txt
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 * http://www.gnu.org/copyleft/gpl.html
 *
 * @file
 */

/**
 * Represents a title within MediaWiki.
 * Optionally may contain an interwiki designation or namespace.
 * @note This class can fetch various kinds of data from the database;
 *       however, it does so inefficiently.
 * @note Consider using a TitleValue object instead. TitleValue is more lightweight
 *       and does not rely on global state or the database.
 *
 * @internal documentation reviewed 15 Mar 2010
 */
class Title {
	/** @var MapCacheLRU */
	static private $titleCache = null;

	/**
	 * Title::newFromText maintains a cache to avoid expensive re-normalization of
	 * commonly used titles. On a batch operation this can become a memory leak
	 * if not bounded. After hitting this many titles reset the cache.
	 */
	const CACHE_MAX = 1000;

	/**
	 * Used to be GAID_FOR_UPDATE define. Used with getArticleID() and friends
	 * to use the master DB
	 */
	const GAID_FOR_UPDATE = 1;

	/**
	 * @name Private member variables
	 * Please use the accessor functions instead.
	 * @private
	 */
	// @{

	/** @var string Text form (spaces not underscores) of the main part */
	public $mTextform = '';

	/** @var string URL-encoded form of the main part */
	public $mUrlform = '';

	/** @var string Main part with underscores */
	public $mDbkeyform = '';

	/** @var string Database key with the initial letter in the case specified by the user */
	protected $mUserCaseDBKey;

	/** @var int Namespace index, i.e. one of the NS_xxxx constants */
	public $mNamespace = NS_MAIN;

	/** @var string Interwiki prefix */
	public $mInterwiki = '';

	/** @var bool Was this Title created from a string with a local interwiki prefix? */
	private $mLocalInterwiki = false;

	/** @var string Title fragment (i.e. the bit after the #) */
	public $mFragment = '';

	/** @var int Article ID, fetched from the link cache on demand */
	public $mArticleID = -1;

	/** @var bool|int ID of most recent revision */
	protected $mLatestID = false;

	/**
	 * @var bool|string ID of the page's content model, i.e. one of the
	 *   CONTENT_MODEL_XXX constants
	 */
	public $mContentModel = false;

	/** @var int Estimated number of revisions; null of not loaded */
	private $mEstimateRevisions;

	/** @var array Array of groups allowed to edit this article */
	public $mRestrictions = array();

	/** @var bool */
	protected $mOldRestrictions = false;

	/** @var bool Cascade restrictions on this page to included templates and images? */
	public $mCascadeRestriction;

	/** Caching the results of getCascadeProtectionSources */
	public $mCascadingRestrictions;

	/** @var array When do the restrictions on this page expire? */
	protected $mRestrictionsExpiry = array();

	/** @var bool Are cascading restrictions in effect on this page? */
	protected $mHasCascadingRestrictions;

	/** @var array Where are the cascading restrictions coming from on this page? */
	public $mCascadeSources;

	/** @var bool Boolean for initialisation on demand */
	public $mRestrictionsLoaded = false;

	/** @var string Text form including namespace/interwiki, initialised on demand */
	protected $mPrefixedText = null;

	/** @var mixed Cached value for getTitleProtection (create protection) */
	public $mTitleProtection;

	/**
	 * @var int Namespace index when there is no namespace. Don't change the
	 *   following default, NS_MAIN is hardcoded in several places. See bug 696.
	 *   Zero except in {{transclusion}} tags.
	 */
	public $mDefaultNamespace = NS_MAIN;

	/**
	 * @var bool Is $wgUser watching this page? null if unfilled, accessed
	 * through userIsWatching()
	 */
	protected $mWatched = null;

	/** @var int The page length, 0 for special pages */
	protected $mLength = -1;

	/** @var null Is the article at this title a redirect? */
	public $mRedirect = null;

	/** @var array Associative array of user ID -> timestamp/false */
	private $mNotificationTimestamp = array();

	/** @var bool Whether a page has any subpages */
	private $mHasSubpages;

	/** @var bool The (string) language code of the page's language and content code. */
	private $mPageLanguage = false;

	/** @var string The page language code from the database */
	private $mDbPageLanguage = null;

	/** @var TitleValue A corresponding TitleValue object */
	private $mTitleValue = null;

	/** @var bool Would deleting this page be a big deletion? */
	private $mIsBigDeletion = null;
	// @}

	/**
	 * B/C kludge: provide a TitleParser for use by Title.
	 * Ideally, Title would have no methods that need this.
	 * Avoid usage of this singleton by using TitleValue
	 * and the associated services when possible.
	 *
	 * @return TitleParser
	 */
	private static function getTitleParser() {
		global $wgContLang, $wgLocalInterwikis;

		static $titleCodec = null;
		static $titleCodecFingerprint = null;

		// $wgContLang and $wgLocalInterwikis may change (especially while testing),
		// make sure we are using the right one. To detect changes over the course
		// of a request, we remember a fingerprint of the config used to create the
		// codec singleton, and re-create it if the fingerprint doesn't match.
		$fingerprint = spl_object_hash( $wgContLang ) . '|' . join( '+', $wgLocalInterwikis );

		if ( $fingerprint !== $titleCodecFingerprint ) {
			$titleCodec = null;
		}

		if ( !$titleCodec ) {
			$titleCodec = new MediaWikiTitleCodec(
				$wgContLang,
				GenderCache::singleton(),
				$wgLocalInterwikis
			);
			$titleCodecFingerprint = $fingerprint;
		}

		return $titleCodec;
	}

	/**
	 * B/C kludge: provide a TitleParser for use by Title.
	 * Ideally, Title would have no methods that need this.
	 * Avoid usage of this singleton by using TitleValue
	 * and the associated services when possible.
	 *
	 * @return TitleFormatter
	 */
	private static function getTitleFormatter() {
		//NOTE: we know that getTitleParser() returns a MediaWikiTitleCodec,
		//      which implements TitleFormatter.
		return self::getTitleParser();
	}

	function __construct() {
	}

	/**
	 * Create a new Title from a prefixed DB key
	 *
	 * @param string $key The database key, which has underscores
	 *	instead of spaces, possibly including namespace and
	 *	interwiki prefixes
	 * @return Title|null Title, or null on an error
	 */
	public static function newFromDBkey( $key ) {
		$t = new Title();
		$t->mDbkeyform = $key;
		if ( $t->secureAndSplit() ) {
			return $t;
		} else {
			return null;
		}
	}

	/**
	 * Create a new Title from a TitleValue
	 *
	 * @param TitleValue $titleValue Assumed to be safe.
	 *
	 * @return Title
	 */
	public static function newFromTitleValue( TitleValue $titleValue ) {
		return self::makeTitle(
			$titleValue->getNamespace(),
			$titleValue->getText(),
			$titleValue->getFragment() );
	}

	/**
	 * Create a new Title from text, such as what one would find in a link. De-
	 * codes any HTML entities in the text.
	 *
	 * @param string $text The link text; spaces, prefixes, and an
	 *   initial ':' indicating the main namespace are accepted.
	 * @param int $defaultNamespace The namespace to use if none is specified
	 *   by a prefix.  If you want to force a specific namespace even if
	 *   $text might begin with a namespace prefix, use makeTitle() or
	 *   makeTitleSafe().
	 * @throws MWException
	 * @return Title|null Title or null on an error.
	 */
	public static function newFromText( $text, $defaultNamespace = NS_MAIN ) {
		if ( is_object( $text ) ) {
			throw new MWException( 'Title::newFromText given an object' );
		}

		$cache = self::getTitleCache();

		/**
		 * Wiki pages often contain multiple links to the same page.
		 * Title normalization and parsing can become expensive on
		 * pages with many links, so we can save a little time by
		 * caching them.
		 *
		 * In theory these are value objects and won't get changed...
		 */
		if ( $defaultNamespace == NS_MAIN && $cache->has( $text ) ) {
			return $cache->get( $text );
		}

		# Convert things like &eacute; &#257; or &#x3017; into normalized (bug 14952) text
		$filteredText = Sanitizer::decodeCharReferencesAndNormalize( $text );

		$t = new Title();
		$t->mDbkeyform = str_replace( ' ', '_', $filteredText );
		$t->mDefaultNamespace = intval( $defaultNamespace );

		if ( $t->secureAndSplit() ) {
			if ( $defaultNamespace == NS_MAIN ) {
				$cache->set( $text, $t );
			}
			return $t;
		} else {
			return null;
		}
	}

	/**
	 * THIS IS NOT THE FUNCTION YOU WANT. Use Title::newFromText().
	 *
	 * Example of wrong and broken code:
	 * $title = Title::newFromURL( $wgRequest->getVal( 'title' ) );
	 *
	 * Example of right code:
	 * $title = Title::newFromText( $wgRequest->getVal( 'title' ) );
	 *
	 * Create a new Title from URL-encoded text. Ensures that
	 * the given title's length does not exceed the maximum.
	 *
	 * @param string $url The title, as might be taken from a URL
	 * @return Title|null The new object, or null on an error
	 */
	public static function newFromURL( $url ) {
		$t = new Title();

		# For compatibility with old buggy URLs. "+" is usually not valid in titles,
		# but some URLs used it as a space replacement and they still come
		# from some external search tools.
		if ( strpos( self::legalChars(), '+' ) === false ) {
			$url = str_replace( '+', ' ', $url );
		}

		$t->mDbkeyform = str_replace( ' ', '_', $url );
		if ( $t->secureAndSplit() ) {
			return $t;
		} else {
			return null;
		}
	}

	/**
	 * @return MapCacheLRU
	 */
	private static function getTitleCache() {
		if ( self::$titleCache == null ) {
			self::$titleCache = new MapCacheLRU( self::CACHE_MAX );
		}
		return self::$titleCache;
	}

	/**
	 * Returns a list of fields that are to be selected for initializing Title
	 * objects or LinkCache entries. Uses $wgContentHandlerUseDB to determine
	 * whether to include page_content_model.
	 *
	 * @return array
	 */
	protected static function getSelectFields() {
		global $wgContentHandlerUseDB;

		$fields = array(
			'page_namespace', 'page_title', 'page_id',
			'page_len', 'page_is_redirect', 'page_latest',
		);

		if ( $wgContentHandlerUseDB ) {
			$fields[] = 'page_content_model';
		}

		return $fields;
	}

	/**
	 * Create a new Title from an article ID
	 *
	 * @param int $id The page_id corresponding to the Title to create
	 * @param int $flags Use Title::GAID_FOR_UPDATE to use master
	 * @return Title|null The new object, or null on an error
	 */
	public static function newFromID( $id, $flags = 0 ) {
		$db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
		$row = $db->selectRow(
			'page',
			self::getSelectFields(),
			array( 'page_id' => $id ),
			__METHOD__
		);
		if ( $row !== false ) {
			$title = Title::newFromRow( $row );
		} else {
			$title = null;
		}
		return $title;
	}

	/**
	 * Make an array of titles from an array of IDs
	 *
	 * @param int[] $ids Array of IDs
	 * @return Title[] Array of Titles
	 */
	public static function newFromIDs( $ids ) {
		if ( !count( $ids ) ) {
			return array();
		}
		$dbr = wfGetDB( DB_SLAVE );

		$res = $dbr->select(
			'page',
			self::getSelectFields(),
			array( 'page_id' => $ids ),
			__METHOD__
		);

		$titles = array();
		foreach ( $res as $row ) {
			$titles[] = Title::newFromRow( $row );
		}
		return $titles;
	}

	/**
	 * Make a Title object from a DB row
	 *
	 * @param stdClass $row Object database row (needs at least page_title,page_namespace)
	 * @return Title Corresponding Title
	 */
	public static function newFromRow( $row ) {
		$t = self::makeTitle( $row->page_namespace, $row->page_title );
		$t->loadFromRow( $row );
		return $t;
	}

	/**
	 * Load Title object fields from a DB row.
	 * If false is given, the title will be treated as non-existing.
	 *
	 * @param stdClass|bool $row Database row
	 */
	public function loadFromRow( $row ) {
		if ( $row ) { // page found
			if ( isset( $row->page_id ) ) {
				$this->mArticleID = (int)$row->page_id;
			}
			if ( isset( $row->page_len ) ) {
				$this->mLength = (int)$row->page_len;
			}
			if ( isset( $row->page_is_redirect ) ) {
				$this->mRedirect = (bool)$row->page_is_redirect;
			}
			if ( isset( $row->page_latest ) ) {
				$this->mLatestID = (int)$row->page_latest;
			}
			if ( isset( $row->page_content_model ) ) {
				$this->mContentModel = strval( $row->page_content_model );
			} else {
				$this->mContentModel = false; # initialized lazily in getContentModel()
			}
			if ( isset( $row->page_lang ) ) {
				$this->mDbPageLanguage = (string)$row->page_lang;
			}
		} else { // page not found
			$this->mArticleID = 0;
			$this->mLength = 0;
			$this->mRedirect = false;
			$this->mLatestID = 0;
			$this->mContentModel = false; # initialized lazily in getContentModel()
		}
	}

	/**
	 * Create a new Title from a namespace index and a DB key.
	 * It's assumed that $ns and $title are *valid*, for instance when
	 * they came directly from the database or a special page name.
	 * For convenience, spaces are converted to underscores so that
	 * eg user_text fields can be used directly.
	 *
	 * @param int $ns The namespace of the article
	 * @param string $title The unprefixed database key form
	 * @param string $fragment The link fragment (after the "#")
	 * @param string $interwiki The interwiki prefix
	 * @return Title The new object
	 */
	public static function &makeTitle( $ns, $title, $fragment = '', $interwiki = '' ) {
		$t = new Title();
		$t->mInterwiki = $interwiki;
		$t->mFragment = $fragment;
		$t->mNamespace = $ns = intval( $ns );
		$t->mDbkeyform = str_replace( ' ', '_', $title );
		$t->mArticleID = ( $ns >= 0 ) ? -1 : 0;
		$t->mUrlform = wfUrlencode( $t->mDbkeyform );
		$t->mTextform = str_replace( '_', ' ', $title );
		$t->mContentModel = false; # initialized lazily in getContentModel()
		return $t;
	}

	/**
	 * Create a new Title from a namespace index and a DB key.
	 * The parameters will be checked for validity, which is a bit slower
	 * than makeTitle() but safer for user-provided data.
	 *
	 * @param int $ns The namespace of the article
	 * @param string $title Database key form
	 * @param string $fragment The link fragment (after the "#")
	 * @param string $interwiki Interwiki prefix
	 * @return Title The new object, or null on an error
	 */
	public static function makeTitleSafe( $ns, $title, $fragment = '', $interwiki = '' ) {
		if ( !MWNamespace::exists( $ns ) ) {
			return null;
		}

		$t = new Title();
		$t->mDbkeyform = Title::makeName( $ns, $title, $fragment, $interwiki );
		if ( $t->secureAndSplit() ) {
			return $t;
		} else {
			return null;
		}
	}

	/**
	 * Create a new Title for the Main Page
	 *
	 * @return Title The new object
	 */
	public static function newMainPage() {
		$title = Title::newFromText( wfMessage( 'mainpage' )->inContentLanguage()->text() );
		// Don't give fatal errors if the message is broken
		if ( !$title ) {
			$title = Title::newFromText( 'Main Page' );
		}
		return $title;
	}

	/**
	 * Extract a redirect destination from a string and return the
	 * Title, or null if the text doesn't contain a valid redirect
	 * This will only return the very next target, useful for
	 * the redirect table and other checks that don't need full recursion
	 *
	 * @param string $text Text with possible redirect
	 * @return Title The corresponding Title
	 * @deprecated since 1.21, use Content::getRedirectTarget instead.
	 */
	public static function newFromRedirect( $text ) {
		ContentHandler::deprecated( __METHOD__, '1.21' );

		$content = ContentHandler::makeContent( $text, null, CONTENT_MODEL_WIKITEXT );
		return $content->getRedirectTarget();
	}

	/**
	 * Extract a redirect destination from a string and return the
	 * Title, or null if the text doesn't contain a valid redirect
	 * This will recurse down $wgMaxRedirects times or until a non-redirect target is hit
	 * in order to provide (hopefully) the Title of the final destination instead of another redirect
	 *
	 * @param string $text Text with possible redirect
	 * @return Title
	 * @deprecated since 1.21, use Content::getUltimateRedirectTarget instead.
	 */
	public static function newFromRedirectRecurse( $text ) {
		ContentHandler::deprecated( __METHOD__, '1.21' );

		$content = ContentHandler::makeContent( $text, null, CONTENT_MODEL_WIKITEXT );
		return $content->getUltimateRedirectTarget();
	}

	/**
	 * Extract a redirect destination from a string and return an
	 * array of Titles, or null if the text doesn't contain a valid redirect
	 * The last element in the array is the final destination after all redirects
	 * have been resolved (up to $wgMaxRedirects times)
	 *
	 * @param string $text Text with possible redirect
	 * @return Title[] Array of Titles, with the destination last
	 * @deprecated since 1.21, use Content::getRedirectChain instead.
	 */
	public static function newFromRedirectArray( $text ) {
		ContentHandler::deprecated( __METHOD__, '1.21' );

		$content = ContentHandler::makeContent( $text, null, CONTENT_MODEL_WIKITEXT );
		return $content->getRedirectChain();
	}

	/**
	 * Get the prefixed DB key associated with an ID
	 *
	 * @param int $id The page_id of the article
	 * @return Title|null An object representing the article, or null if no such article was found
	 */
	public static function nameOf( $id ) {
		$dbr = wfGetDB( DB_SLAVE );

		$s = $dbr->selectRow(
			'page',
			array( 'page_namespace', 'page_title' ),
			array( 'page_id' => $id ),
			__METHOD__
		);
		if ( $s === false ) {
			return null;
		}

		$n = self::makeName( $s->page_namespace, $s->page_title );
		return $n;
	}

	/**
	 * Get a regex character class describing the legal characters in a link
	 *
	 * @return string The list of characters, not delimited
	 */
	public static function legalChars() {
		global $wgLegalTitleChars;
		return $wgLegalTitleChars;
	}

	/**
	 * Returns a simple regex that will match on characters and sequences invalid in titles.
	 * Note that this doesn't pick up many things that could be wrong with titles, but that
	 * replacing this regex with something valid will make many titles valid.
	 *
	 * @todo move this into MediaWikiTitleCodec
	 *
	 * @return string Regex string
	 */
	static function getTitleInvalidRegex() {
		static $rxTc = false;
		if ( !$rxTc ) {
			# Matching titles will be held as illegal.
			$rxTc = '/' .
				# Any character not allowed is forbidden...
				'[^' . self::legalChars() . ']' .
				# URL percent encoding sequences interfere with the ability
				# to round-trip titles -- you can't link to them consistently.
				'|%[0-9A-Fa-f]{2}' .
				# XML/HTML character references produce similar issues.
				'|&[A-Za-z0-9\x80-\xff]+;' .
				'|&#[0-9]+;' .
				'|&#x[0-9A-Fa-f]+;' .
				'/S';
		}

		return $rxTc;
	}

	/**
	 * Utility method for converting a character sequence from bytes to Unicode.
	 *
	 * Primary usecase being converting $wgLegalTitleChars to a sequence usable in
	 * javascript, as PHP uses UTF-8 bytes where javascript uses Unicode code units.
	 *
	 * @param string $byteClass
	 * @return string
	 */
	public static function convertByteClassToUnicodeClass( $byteClass ) {
		$length = strlen( $byteClass );
		// Input token queue
		$x0 = $x1 = $x2 = '';
		// Decoded queue
		$d0 = $d1 = $d2 = '';
		// Decoded integer codepoints
		$ord0 = $ord1 = $ord2 = 0;
		// Re-encoded queue
		$r0 = $r1 = $r2 = '';
		// Output
		$out = '';
		// Flags
		$allowUnicode = false;
		for ( $pos = 0; $pos < $length; $pos++ ) {
			// Shift the queues down
			$x2 = $x1;
			$x1 = $x0;
			$d2 = $d1;
			$d1 = $d0;
			$ord2 = $ord1;
			$ord1 = $ord0;
			$r2 = $r1;
			$r1 = $r0;
			// Load the current input token and decoded values
			$inChar = $byteClass[$pos];
			if ( $inChar == '\\' ) {
				if ( preg_match( '/x([0-9a-fA-F]{2})/A', $byteClass, $m, 0, $pos + 1 ) ) {
					$x0 = $inChar . $m[0];
					$d0 = chr( hexdec( $m[1] ) );
					$pos += strlen( $m[0] );
				} elseif ( preg_match( '/[0-7]{3}/A', $byteClass, $m, 0, $pos + 1 ) ) {
					$x0 = $inChar . $m[0];
					$d0 = chr( octdec( $m[0] ) );
					$pos += strlen( $m[0] );
				} elseif ( $pos + 1 >= $length ) {
					$x0 = $d0 = '\\';
				} else {
					$d0 = $byteClass[$pos + 1];
					$x0 = $inChar . $d0;
					$pos += 1;
				}
			} else {
				$x0 = $d0 = $inChar;
			}
			$ord0 = ord( $d0 );
			// Load the current re-encoded value
			if ( $ord0 < 32 || $ord0 == 0x7f ) {
				$r0 = sprintf( '\x%02x', $ord0 );
			} elseif ( $ord0 >= 0x80 ) {
				// Allow unicode if a single high-bit character appears
				$r0 = sprintf( '\x%02x', $ord0 );
				$allowUnicode = true;
			} elseif ( strpos( '-\\[]^', $d0 ) !== false ) {
				$r0 = '\\' . $d0;
			} else {
				$r0 = $d0;
			}
			// Do the output
			if ( $x0 !== '' && $x1 === '-' && $x2 !== '' ) {
				// Range
				if ( $ord2 > $ord0 ) {
					// Empty range
				} elseif ( $ord0 >= 0x80 ) {
					// Unicode range
					$allowUnicode = true;
					if ( $ord2 < 0x80 ) {
						// Keep the non-unicode section of the range
						$out .= "$r2-\\x7F";
					}
				} else {
					// Normal range
					$out .= "$r2-$r0";
				}
				// Reset state to the initial value
				$x0 = $x1 = $d0 = $d1 = $r0 = $r1 = '';
			} elseif ( $ord2 < 0x80 ) {
				// ASCII character
				$out .= $r2;
			}
		}
		if ( $ord1 < 0x80 ) {
			$out .= $r1;
		}
		if ( $ord0 < 0x80 ) {
			$out .= $r0;
		}
		if ( $allowUnicode ) {
			$out .= '\u0080-\uFFFF';
		}
		return $out;
	}

	/**
	 * Make a prefixed DB key from a DB key and a namespace index
	 *
	 * @param int $ns Numerical representation of the namespace
	 * @param string $title The DB key form the title
	 * @param string $fragment The link fragment (after the "#")
	 * @param string $interwiki The interwiki prefix
	 * @return string The prefixed form of the title
	 */
	public static function makeName( $ns, $title, $fragment = '', $interwiki = '' ) {
		global $wgContLang;

		$namespace = $wgContLang->getNsText( $ns );
		$name = $namespace == '' ? $title : "$namespace:$title";
		if ( strval( $interwiki ) != '' ) {
			$name = "$interwiki:$name";
		}
		if ( strval( $fragment ) != '' ) {
			$name .= '#' . $fragment;
		}
		return $name;
	}

	/**
	 * Escape a text fragment, say from a link, for a URL
	 *
	 * @param string $fragment Containing a URL or link fragment (after the "#")
	 * @return string Escaped string
	 */
	static function escapeFragmentForURL( $fragment ) {
		# Note that we don't urlencode the fragment.  urlencoded Unicode
		# fragments appear not to work in IE (at least up to 7) or in at least
		# one version of Opera 9.x.  The W3C validator, for one, doesn't seem
		# to care if they aren't encoded.
		return Sanitizer::escapeId( $fragment, 'noninitial' );
	}

	/**
	 * Callback for usort() to do title sorts by (namespace, title)
	 *
	 * @param Title $a
	 * @param Title $b
	 *
	 * @return int Result of string comparison, or namespace comparison
	 */
	public static function compare( $a, $b ) {
		if ( $a->getNamespace() == $b->getNamespace() ) {
			return strcmp( $a->getText(), $b->getText() );
		} else {
			return $a->getNamespace() - $b->getNamespace();
		}
	}

	/**
	 * Determine whether the object refers to a page within
	 * this project.
	 *
	 * @return bool True if this is an in-project interwiki link or a wikilink, false otherwise
	 */
	public function isLocal() {
		if ( $this->isExternal() ) {
			$iw = Interwiki::fetch( $this->mInterwiki );
			if ( $iw ) {
				return $iw->isLocal();
			}
		}
		return true;
	}

	/**
	 * Is this Title interwiki?
	 *
	 * @return bool
	 */
	public function isExternal() {
		return $this->mInterwiki !== '';
	}

	/**
	 * Get the interwiki prefix
	 *
	 * Use Title::isExternal to check if a interwiki is set
	 *
	 * @return string Interwiki prefix
	 */
	public function getInterwiki() {
		return $this->mInterwiki;
	}

	/**
	 * Was this a local interwiki link?
	 *
	 * @return bool
	 */
	public function wasLocalInterwiki() {
		return $this->mLocalInterwiki;
	}

	/**
	 * Determine whether the object refers to a page within
	 * this project and is transcludable.
	 *
	 * @return bool True if this is transcludable
	 */
	public function isTrans() {
		if ( !$this->isExternal() ) {
			return false;
		}

		return Interwiki::fetch( $this->mInterwiki )->isTranscludable();
	}

	/**
	 * Returns the DB name of the distant wiki which owns the object.
	 *
	 * @return string The DB name
	 */
	public function getTransWikiID() {
		if ( !$this->isExternal() ) {
			return false;
		}

		return Interwiki::fetch( $this->mInterwiki )->getWikiID();
	}

	/**
	 * Get a TitleValue object representing this Title.
	 *
	 * @note Not all valid Titles have a corresponding valid TitleValue
	 * (e.g. TitleValues cannot represent page-local links that have a
	 * fragment but no title text).
	 *
	 * @return TitleValue|null
	 */
	public function getTitleValue() {
		if ( $this->mTitleValue === null ) {
			try {
				$this->mTitleValue = new TitleValue(
					$this->getNamespace(),
					$this->getDBkey(),
					$this->getFragment() );
			} catch ( InvalidArgumentException $ex ) {
				wfDebug( __METHOD__ . ': Can\'t create a TitleValue for [[' .
					$this->getPrefixedText() . ']]: ' . $ex->getMessage() . "\n" );
			}
		}

		return $this->mTitleValue;
	}

	/**
	 * Get the text form (spaces not underscores) of the main part
	 *
	 * @return string Main part of the title
	 */
	public function getText() {
		return $this->mTextform;
	}

	/**
	 * Get the URL-encoded form of the main part
	 *
	 * @return string Main part of the title, URL-encoded
	 */
	public function getPartialURL() {
		return $this->mUrlform;
	}

	/**
	 * Get the main part with underscores
	 *
	 * @return string Main part of the title, with underscores
	 */
	public function getDBkey() {
		return $this->mDbkeyform;
	}

	/**
	 * Get the DB key with the initial letter case as specified by the user
	 *
	 * @return string DB key
	 */
	function getUserCaseDBKey() {
		if ( !is_null( $this->mUserCaseDBKey ) ) {
			return $this->mUserCaseDBKey;
		} else {
			// If created via makeTitle(), $this->mUserCaseDBKey is not set.
			return $this->mDbkeyform;
		}
	}

	/**
	 * Get the namespace index, i.e. one of the NS_xxxx constants.
	 *
	 * @return int Namespace index
	 */
	public function getNamespace() {
		return $this->mNamespace;
	}

	/**
	 * Get the page's content model id, see the CONTENT_MODEL_XXX constants.
	 *
	 * @throws MWException
	 * @param int $flags A bit field; may be Title::GAID_FOR_UPDATE to select for update
	 * @return string Content model id
	 */
	public function getContentModel( $flags = 0 ) {
		# Calling getArticleID() loads the field from cache as needed
		if ( !$this->mContentModel && $this->getArticleID( $flags ) ) {
			$linkCache = LinkCache::singleton();
			$this->mContentModel = $linkCache->getGoodLinkFieldObj( $this, 'model' );
		}

		if ( !$this->mContentModel ) {
			$this->mContentModel = ContentHandler::getDefaultModelFor( $this );
		}

		if ( !$this->mContentModel ) {
			throw new MWException( 'Failed to determine content model!' );
		}

		return $this->mContentModel;
	}

	/**
	 * Convenience method for checking a title's content model name
	 *
	 * @param string $id The content model ID (use the CONTENT_MODEL_XXX constants).
	 * @return bool True if $this->getContentModel() == $id
	 */
	public function hasContentModel( $id ) {
		return $this->getContentModel() == $id;
	}

	/**
	 * Get the namespace text
	 *
	 * @return string Namespace text
	 */
	public function getNsText() {
		if ( $this->isExternal() ) {
			// This probably shouldn't even happen. ohh man, oh yuck.
			// But for interwiki transclusion it sometimes does.
			// Shit. Shit shit shit.
			//
			// Use the canonical namespaces if possible to try to
			// resolve a foreign namespace.
			if ( MWNamespace::exists( $this->mNamespace ) ) {
				return MWNamespace::getCanonicalName( $this->mNamespace );
			}
		}

		try {
			$formatter = self::getTitleFormatter();
			return $formatter->getNamespaceName( $this->mNamespace, $this->mDbkeyform );
		} catch ( InvalidArgumentException $ex ) {
			wfDebug( __METHOD__ . ': ' . $ex->getMessage() . "\n" );
			return false;
		}
	}

	/**
	 * Get the namespace text of the subject (rather than talk) page
	 *
	 * @return string Namespace text
	 */
	public function getSubjectNsText() {
		global $wgContLang;
		return $wgContLang->getNsText( MWNamespace::getSubject( $this->mNamespace ) );
	}

	/**
	 * Get the namespace text of the talk page
	 *
	 * @return string Namespace text
	 */
	public function getTalkNsText() {
		global $wgContLang;
		return $wgContLang->getNsText( MWNamespace::getTalk( $this->mNamespace ) );
	}

	/**
	 * Could this title have a corresponding talk page?
	 *
	 * @return bool
	 */
	public function canTalk() {
		return MWNamespace::canTalk( $this->mNamespace );
	}

	/**
	 * Is this in a namespace that allows actual pages?
	 *
	 * @return bool
	 * @internal note -- uses hardcoded namespace index instead of constants
	 */
	public function canExist() {
		return $this->mNamespace >= NS_MAIN;
	}

	/**
	 * Can this title be added to a user's watchlist?
	 *
	 * @return bool
	 */
	public function isWatchable() {
		return !$this->isExternal() && MWNamespace::isWatchable( $this->getNamespace() );
	}

	/**
	 * Returns true if this is a special page.
	 *
	 * @return bool
	 */
	public function isSpecialPage() {
		return $this->getNamespace() == NS_SPECIAL;
	}

	/**
	 * Returns true if this title resolves to the named special page
	 *
	 * @param string $name The special page name
	 * @return bool
	 */
	public function isSpecial( $name ) {
		if ( $this->isSpecialPage() ) {
			list( $thisName, /* $subpage */ ) = SpecialPageFactory::resolveAlias( $this->getDBkey() );
			if ( $name == $thisName ) {
				return true;
			}
		}
		return false;
	}

	/**
	 * If the Title refers to a special page alias which is not the local default, resolve
	 * the alias, and localise the name as necessary.  Otherwise, return $this
	 *
	 * @return Title
	 */
	public function fixSpecialName() {
		if ( $this->isSpecialPage() ) {
			list( $canonicalName, $par ) = SpecialPageFactory::resolveAlias( $this->mDbkeyform );
			if ( $canonicalName ) {
				$localName = SpecialPageFactory::getLocalNameFor( $canonicalName, $par );
				if ( $localName != $this->mDbkeyform ) {
					return Title::makeTitle( NS_SPECIAL, $localName );
				}
			}
		}
		return $this;
	}

	/**
	 * Returns true if the title is inside the specified namespace.
	 *
	 * Please make use of this instead of comparing to getNamespace()
	 * This function is much more resistant to changes we may make
	 * to namespaces than code that makes direct comparisons.
	 * @param int $ns The namespace
	 * @return bool
	 * @since 1.19
	 */
	public function inNamespace( $ns ) {
		return MWNamespace::equals( $this->getNamespace(), $ns );
	}

	/**
	 * Returns true if the title is inside one of the specified namespaces.
	 *
	 * @param int $namespaces,... The namespaces to check for
	 * @return bool
	 * @since 1.19
	 */
	public function inNamespaces( /* ... */ ) {
		$namespaces = func_get_args();
		if ( count( $namespaces ) > 0 && is_array( $namespaces[0] ) ) {
			$namespaces = $namespaces[0];
		}

		foreach ( $namespaces as $ns ) {
			if ( $this->inNamespace( $ns ) ) {
				return true;
			}
		}

		return false;
	}

	/**
	 * Returns true if the title has the same subject namespace as the
	 * namespace specified.
	 * For example this method will take NS_USER and return true if namespace
	 * is either NS_USER or NS_USER_TALK since both of them have NS_USER
	 * as their subject namespace.
	 *
	 * This is MUCH simpler than individually testing for equivalence
	 * against both NS_USER and NS_USER_TALK, and is also forward compatible.
	 * @since 1.19
	 * @param int $ns
	 * @return bool
	 */
	public function hasSubjectNamespace( $ns ) {
		return MWNamespace::subjectEquals( $this->getNamespace(), $ns );
	}

	/**
	 * Is this Title in a namespace which contains content?
	 * In other words, is this a content page, for the purposes of calculating
	 * statistics, etc?
	 *
	 * @return bool
	 */
	public function isContentPage() {
		return MWNamespace::isContent( $this->getNamespace() );
	}

	/**
	 * Would anybody with sufficient privileges be able to move this page?
	 * Some pages just aren't movable.
	 *
	 * @return bool
	 */
	public function isMovable() {
		if ( !MWNamespace::isMovable( $this->getNamespace() ) || $this->isExternal() ) {
			// Interwiki title or immovable namespace. Hooks don't get to override here
			return false;
		}

		$result = true;
		wfRunHooks( 'TitleIsMovable', array( $this, &$result ) );
		return $result;
	}

	/**
	 * Is this the mainpage?
	 * @note Title::newFromText seems to be sufficiently optimized by the title
	 * cache that we don't need to over-optimize by doing direct comparisons and
	 * accidentally creating new bugs where $title->equals( Title::newFromText() )
	 * ends up reporting something differently than $title->isMainPage();
	 *
	 * @since 1.18
	 * @return bool
	 */
	public function isMainPage() {
		return $this->equals( Title::newMainPage() );
	}

	/**
	 * Is this a subpage?
	 *
	 * @return bool
	 */
	public function isSubpage() {
		return MWNamespace::hasSubpages( $this->mNamespace )
			? strpos( $this->getText(), '/' ) !== false
			: false;
	}

	/**
	 * Is this a conversion table for the LanguageConverter?
	 *
	 * @return bool
	 */
	public function isConversionTable() {
		// @todo ConversionTable should become a separate content model.

		return $this->getNamespace() == NS_MEDIAWIKI &&
			strpos( $this->getText(), 'Conversiontable/' ) === 0;
	}

	/**
	 * Does that page contain wikitext, or it is JS, CSS or whatever?
	 *
	 * @return bool
	 */
	public function isWikitextPage() {
		return $this->hasContentModel( CONTENT_MODEL_WIKITEXT );
	}

	/**
	 * Could this page contain custom CSS or JavaScript for the global UI.
	 * This is generally true for pages in the MediaWiki namespace having CONTENT_MODEL_CSS
	 * or CONTENT_MODEL_JAVASCRIPT.
	 *
	 * This method does *not* return true for per-user JS/CSS. Use isCssJsSubpage()
	 * for that!
	 *
	 * Note that this method should not return true for pages that contain and
	 * show "inactive" CSS or JS.
	 *
	 * @return bool
	 */
	public function isCssOrJsPage() {
		$isCssOrJsPage = NS_MEDIAWIKI == $this->mNamespace
			&& ( $this->hasContentModel( CONTENT_MODEL_CSS )
				|| $this->hasContentModel( CONTENT_MODEL_JAVASCRIPT ) );

		# @note This hook is also called in ContentHandler::getDefaultModel.
		#   It's called here again to make sure hook functions can force this
		#   method to return true even outside the mediawiki namespace.

		wfRunHooks( 'TitleIsCssOrJsPage', array( $this, &$isCssOrJsPage ) );

		return $isCssOrJsPage;
	}

	/**
	 * Is this a .css or .js subpage of a user page?
	 * @return bool
	 */
	public function isCssJsSubpage() {
		return ( NS_USER == $this->mNamespace && $this->isSubpage()
				&& ( $this->hasContentModel( CONTENT_MODEL_CSS )
					|| $this->hasContentModel( CONTENT_MODEL_JAVASCRIPT ) ) );
	}

	/**
	 * Trim down a .css or .js subpage title to get the corresponding skin name
	 *
	 * @return string Containing skin name from .css or .js subpage title
	 */
	public function getSkinFromCssJsSubpage() {
		$subpage = explode( '/', $this->mTextform );
		$subpage = $subpage[count( $subpage ) - 1];
		$lastdot = strrpos( $subpage, '.' );
		if ( $lastdot === false ) {
			return $subpage; # Never happens: only called for names ending in '.css' or '.js'
		}
		return substr( $subpage, 0, $lastdot );
	}

	/**
	 * Is this a .css subpage of a user page?
	 *
	 * @return bool
	 */
	public function isCssSubpage() {
		return ( NS_USER == $this->mNamespace && $this->isSubpage()
			&& $this->hasContentModel( CONTENT_MODEL_CSS ) );
	}

	/**
	 * Is this a .js subpage of a user page?
	 *
	 * @return bool
	 */
	public function isJsSubpage() {
		return ( NS_USER == $this->mNamespace && $this->isSubpage()
			&& $this->hasContentModel( CONTENT_MODEL_JAVASCRIPT ) );
	}

	/**
	 * Is this a talk page of some sort?
	 *
	 * @return bool
	 */
	public function isTalkPage() {
		return MWNamespace::isTalk( $this->getNamespace() );
	}

	/**
	 * Get a Title object associated with the talk page of this article
	 *
	 * @return Title The object for the talk page
	 */
	public function getTalkPage() {
		return Title::makeTitle( MWNamespace::getTalk( $this->getNamespace() ), $this->getDBkey() );
	}

	/**
	 * Get a title object associated with the subject page of this
	 * talk page
	 *
	 * @return Title The object for the subject page
	 */
	public function getSubjectPage() {
		// Is this the same title?
		$subjectNS = MWNamespace::getSubject( $this->getNamespace() );
		if ( $this->getNamespace() == $subjectNS ) {
			return $this;
		}
		return Title::makeTitle( $subjectNS, $this->getDBkey() );
	}

	/**
	 * Get the default namespace index, for when there is no namespace
	 *
	 * @return int Default namespace index
	 */
	public function getDefaultNamespace() {
		return $this->mDefaultNamespace;
	}

	/**
	 * Get the Title fragment (i.e.\ the bit after the #) in text form
	 *
	 * Use Title::hasFragment to check for a fragment
	 *
	 * @return string Title fragment
	 */
	public function getFragment() {
		return $this->mFragment;
	}

	/**
	 * Check if a Title fragment is set
	 *
	 * @return bool
	 * @since 1.23
	 */
	public function hasFragment() {
		return $this->mFragment !== '';
	}

	/**
	 * Get the fragment in URL form, including the "#" character if there is one
	 * @return string Fragment in URL form
	 */
	public function getFragmentForURL() {
		if ( !$this->hasFragment() ) {
			return '';
		} else {
			return '#' . Title::escapeFragmentForURL( $this->getFragment() );
		}
	}

	/**
	 * Set the fragment for this title. Removes the first character from the
	 * specified fragment before setting, so it assumes you're passing it with
	 * an initial "#".
	 *
	 * Deprecated for public use, use Title::makeTitle() with fragment parameter.
	 * Still in active use privately.
	 *
	 * @param string $fragment Text
	 */
	public function setFragment( $fragment ) {
		$this->mFragment = str_replace( '_', ' ', substr( $fragment, 1 ) );
	}

	/**
	 * Prefix some arbitrary text with the namespace or interwiki prefix
	 * of this object
	 *
	 * @param string $name The text
	 * @return string The prefixed text
	 */
	private function prefix( $name ) {
		$p = '';
		if ( $this->isExternal() ) {
			$p = $this->mInterwiki . ':';
		}

		if ( 0 != $this->mNamespace ) {
			$p .= $this->getNsText() . ':';
		}
		return $p . $name;
	}

	/**
	 * Get the prefixed database key form
	 *
	 * @return string The prefixed title, with underscores and
	 *  any interwiki and namespace prefixes
	 */
	public function getPrefixedDBkey() {
		$s = $this->prefix( $this->mDbkeyform );
		$s = str_replace( ' ', '_', $s );
		return $s;
	}

	/**
	 * Get the prefixed title with spaces.
	 * This is the form usually used for display
	 *
	 * @return string The prefixed title, with spaces
	 */
	public function getPrefixedText() {
		if ( $this->mPrefixedText === null ) {
			$s = $this->prefix( $this->mTextform );
			$s = str_replace( '_', ' ', $s );
			$this->mPrefixedText = $s;
		}
		return $this->mPrefixedText;
	}

	/**
	 * Return a string representation of this title
	 *
	 * @return string Representation of this title
	 */
	public function __toString() {
		return $this->getPrefixedText();
	}

	/**
	 * Get the prefixed title with spaces, plus any fragment
	 * (part beginning with '#')
	 *
	 * @return string The prefixed title, with spaces and the fragment, including '#'
	 */
	public function getFullText() {
		$text = $this->getPrefixedText();
		if ( $this->hasFragment() ) {
			$text .= '#' . $this->getFragment();
		}
		return $text;
	}

	/**
	 * Get the root page name text without a namespace, i.e. the leftmost part before any slashes
	 *
	 * @par Example:
	 * @code
	 * Title::newFromText('User:Foo/Bar/Baz')->getRootText();
	 * # returns: 'Foo'
	 * @endcode
	 *
	 * @return string Root name
	 * @since 1.20
	 */
	public function getRootText() {
		if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
			return $this->getText();
		}

		return strtok( $this->getText(), '/' );
	}

	/**
	 * Get the root page name title, i.e. the leftmost part before any slashes
	 *
	 * @par Example:
	 * @code
	 * Title::newFromText('User:Foo/Bar/Baz')->getRootTitle();
	 * # returns: Title{User:Foo}
	 * @endcode
	 *
	 * @return Title Root title
	 * @since 1.20
	 */
	public function getRootTitle() {
		return Title::makeTitle( $this->getNamespace(), $this->getRootText() );
	}

	/**
	 * Get the base page name without a namespace, i.e. the part before the subpage name
	 *
	 * @par Example:
	 * @code
	 * Title::newFromText('User:Foo/Bar/Baz')->getBaseText();
	 * # returns: 'Foo/Bar'
	 * @endcode
	 *
	 * @return string Base name
	 */
	public function getBaseText() {
		if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
			return $this->getText();
		}

		$parts = explode( '/', $this->getText() );
		# Don't discard the real title if there's no subpage involved
		if ( count( $parts ) > 1 ) {
			unset( $parts[count( $parts ) - 1] );
		}
		return implode( '/', $parts );
	}

	/**
	 * Get the base page name title, i.e. the part before the subpage name
	 *
	 * @par Example:
	 * @code
	 * Title::newFromText('User:Foo/Bar/Baz')->getBaseTitle();
	 * # returns: Title{User:Foo/Bar}
	 * @endcode
	 *
	 * @return Title Base title
	 * @since 1.20
	 */
	public function getBaseTitle() {
		return Title::makeTitle( $this->getNamespace(), $this->getBaseText() );
	}

	/**
	 * Get the lowest-level subpage name, i.e. the rightmost part after any slashes
	 *
	 * @par Example:
	 * @code
	 * Title::newFromText('User:Foo/Bar/Baz')->getSubpageText();
	 * # returns: "Baz"
	 * @endcode
	 *
	 * @return string Subpage name
	 */
	public function getSubpageText() {
		if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
			return $this->mTextform;
		}
		$parts = explode( '/', $this->mTextform );
		return $parts[count( $parts ) - 1];
	}

	/**
	 * Get the title for a subpage of the current page
	 *
	 * @par Example:
	 * @code
	 * Title::newFromText('User:Foo/Bar/Baz')->getSubpage("Asdf");
	 * # returns: Title{User:Foo/Bar/Baz/Asdf}
	 * @endcode
	 *
	 * @param string $text The subpage name to add to the title
	 * @return Title Subpage title
	 * @since 1.20
	 */
	public function getSubpage( $text ) {
		return Title::makeTitleSafe( $this->getNamespace(), $this->getText() . '/' . $text );
	}

	/**
	 * Get a URL-encoded form of the subpage text
	 *
	 * @return string URL-encoded subpage name
	 */
	public function getSubpageUrlForm() {
		$text = $this->getSubpageText();
		$text = wfUrlencode( str_replace( ' ', '_', $text ) );
		return $text;
	}

	/**
	 * Get a URL-encoded title (not an actual URL) including interwiki
	 *
	 * @return string The URL-encoded form
	 */
	public function getPrefixedURL() {
		$s = $this->prefix( $this->mDbkeyform );
		$s = wfUrlencode( str_replace( ' ', '_', $s ) );
		return $s;
	}

	/**
	 * Helper to fix up the get{Canonical,Full,Link,Local,Internal}URL args
	 * get{Canonical,Full,Link,Local,Internal}URL methods accepted an optional
	 * second argument named variant. This was deprecated in favor
	 * of passing an array of option with a "variant" key
	 * Once $query2 is removed for good, this helper can be dropped
	 * and the wfArrayToCgi moved to getLocalURL();
	 *
	 * @since 1.19 (r105919)
	 * @param array|string $query
	 * @param bool $query2
	 * @return string
	 */
	private static function fixUrlQueryArgs( $query, $query2 = false ) {
		if ( $query2 !== false ) {
			wfDeprecated( "Title::get{Canonical,Full,Link,Local,Internal}URL " .
				"method called with a second parameter is deprecated. Add your " .
				"parameter to an array passed as the first parameter.", "1.19" );
		}
		if ( is_array( $query ) ) {
			$query = wfArrayToCgi( $query );
		}
		if ( $query2 ) {
			if ( is_string( $query2 ) ) {
				// $query2 is a string, we will consider this to be
				// a deprecated $variant argument and add it to the query
				$query2 = wfArrayToCgi( array( 'variant' => $query2 ) );
			} else {
				$query2 = wfArrayToCgi( $query2 );
			}
			// If we have $query content add a & to it first
			if ( $query ) {
				$query .= '&';
			}
			// Now append the queries together
			$query .= $query2;
		}
		return $query;
	}

	/**
	 * Get a real URL referring to this title, with interwiki link and
	 * fragment
	 *
	 * @see self::getLocalURL for the arguments.
	 * @see wfExpandUrl
	 * @param array|string $query
	 * @param bool $query2
	 * @param string $proto Protocol type to use in URL
	 * @return string The URL
	 */
	public function getFullURL( $query = '', $query2 = false, $proto = PROTO_RELATIVE ) {
		$query = self::fixUrlQueryArgs( $query, $query2 );

		# Hand off all the decisions on urls to getLocalURL
		$url = $this->getLocalURL( $query );

		# Expand the url to make it a full url. Note that getLocalURL has the
		# potential to output full urls for a variety of reasons, so we use
		# wfExpandUrl instead of simply prepending $wgServer
		$url = wfExpandUrl( $url, $proto );

		# Finally, add the fragment.
		$url .= $this->getFragmentForURL();

		wfRunHooks( 'GetFullURL', array( &$this, &$url, $query ) );
		return $url;
	}

	/**
	 * Get a URL with no fragment or server name (relative URL) from a Title object.
	 * If this page is generated with action=render, however,
	 * $wgServer is prepended to make an absolute URL.
	 *
	 * @see self::getFullURL to always get an absolute URL.
	 * @see self::getLinkURL to always get a URL that's the simplest URL that will be
	 *  valid to link, locally, to the current Title.
	 * @see self::newFromText to produce a Title object.
	 *
	 * @param string|array $query An optional query string,
	 *   not used for interwiki links. Can be specified as an associative array as well,
	 *   e.g., array( 'action' => 'edit' ) (keys and values will be URL-escaped).
	 *   Some query patterns will trigger various shorturl path replacements.
	 * @param array $query2 An optional secondary query array. This one MUST
	 *   be an array. If a string is passed it will be interpreted as a deprecated
	 *   variant argument and urlencoded into a variant= argument.
	 *   This second query argument will be added to the $query
	 *   The second parameter is deprecated since 1.19. Pass it as a key,value
	 *   pair in the first parameter array instead.
	 *
	 * @return string String of the URL.
	 */
	public function getLocalURL( $query = '', $query2 = false ) {
		global $wgArticlePath, $wgScript, $wgServer, $wgRequest;

		$query = self::fixUrlQueryArgs( $query, $query2 );

		$interwiki = Interwiki::fetch( $this->mInterwiki );
		if ( $interwiki ) {
			$namespace = $this->getNsText();
			if ( $namespace != '' ) {
				# Can this actually happen? Interwikis shouldn't be parsed.
				# Yes! It can in interwiki transclusion. But... it probably shouldn't.
				$namespace .= ':';
			}
			$url = $interwiki->getURL( $namespace . $this->getDBkey() );
			$url = wfAppendQuery( $url, $query );
		} else {
			$dbkey = wfUrlencode( $this->getPrefixedDBkey() );
			if ( $query == '' ) {
				$url = str_replace( '$1', $dbkey, $wgArticlePath );
				wfRunHooks( 'GetLocalURL::Article', array( &$this, &$url ) );
			} else {
				global $wgVariantArticlePath, $wgActionPaths, $wgContLang;
				$url = false;
				$matches = array();

				if ( !empty( $wgActionPaths )
					&& preg_match( '/^(.*&|)action=([^&]*)(&(.*)|)$/', $query, $matches )
				) {
					$action = urldecode( $matches[2] );
					if ( isset( $wgActionPaths[$action] ) ) {
						$query = $matches[1];
						if ( isset( $matches[4] ) ) {
							$query .= $matches[4];
						}
						$url = str_replace( '$1', $dbkey, $wgActionPaths[$action] );
						if ( $query != '' ) {
							$url = wfAppendQuery( $url, $query );
						}
					}
				}

				if ( $url === false
					&& $wgVariantArticlePath
					&& $wgContLang->getCode() === $this->getPageLanguage()->getCode()
					&& $this->getPageLanguage()->hasVariants()
					&& preg_match( '/^variant=([^&]*)$/', $query, $matches )
				) {
					$variant = urldecode( $matches[1] );
					if ( $this->getPageLanguage()->hasVariant( $variant ) ) {
						// Only do the variant replacement if the given variant is a valid
						// variant for the page's language.
						$url = str_replace( '$2', urlencode( $variant ), $wgVariantArticlePath );
						$url = str_replace( '$1', $dbkey, $url );
					}
				}

				if ( $url === false ) {
					if ( $query == '-' ) {
						$query = '';
					}
					$url = "{$wgScript}?title={$dbkey}&{$query}";
				}
			}

			wfRunHooks( 'GetLocalURL::Internal', array( &$this, &$url, $query ) );

			// @todo FIXME: This causes breakage in various places when we
			// actually expected a local URL and end up with dupe prefixes.
			if ( $wgRequest->getVal( 'action' ) == 'render' ) {
				$url = $wgServer . $url;
			}
		}
		wfRunHooks( 'GetLocalURL', array( &$this, &$url, $query ) );
		return $url;
	}

	/**
	 * Get a URL that's the simplest URL that will be valid to link, locally,
	 * to the current Title.  It includes the fragment, but does not include
	 * the server unless action=render is used (or the link is external).  If
	 * there's a fragment but the prefixed text is empty, we just return a link
	 * to the fragment.
	 *
	 * The result obviously should not be URL-escaped, but does need to be
	 * HTML-escaped if it's being output in HTML.
	 *
	 * @param array $query
	 * @param bool $query2
	 * @param string $proto Protocol to use; setting this will cause a full URL to be used
	 * @see self::getLocalURL for the arguments.
	 * @return string The URL
	 */
	public function getLinkURL( $query = '', $query2 = false, $proto = PROTO_RELATIVE ) {
		wfProfileIn( __METHOD__ );
		if ( $this->isExternal() || $proto !== PROTO_RELATIVE ) {
			$ret = $this->getFullURL( $query, $query2, $proto );
		} elseif ( $this->getPrefixedText() === '' && $this->hasFragment() ) {
			$ret = $this->getFragmentForURL();
		} else {
			$ret = $this->getLocalURL( $query, $query2 ) . $this->getFragmentForURL();
		}
		wfProfileOut( __METHOD__ );
		return $ret;
	}

	/**
	 * Get the URL form for an internal link.
	 * - Used in various Squid-related code, in case we have a different
	 * internal hostname for the server from the exposed one.
	 *
	 * This uses $wgInternalServer to qualify the path, or $wgServer
	 * if $wgInternalServer is not set. If the server variable used is
	 * protocol-relative, the URL will be expanded to http://
	 *
	 * @see self::getLocalURL for the arguments.
	 * @return string The URL
	 */
	public function getInternalURL( $query = '', $query2 = false ) {
		global $wgInternalServer, $wgServer;
		$query = self::fixUrlQueryArgs( $query, $query2 );
		$server = $wgInternalServer !== false ? $wgInternalServer : $wgServer;
		$url = wfExpandUrl( $server . $this->getLocalURL( $query ), PROTO_HTTP );
		wfRunHooks( 'GetInternalURL', array( &$this, &$url, $query ) );
		return $url;
	}

	/**
	 * Get the URL for a canonical link, for use in things like IRC and
	 * e-mail notifications. Uses $wgCanonicalServer and the
	 * GetCanonicalURL hook.
	 *
	 * NOTE: Unlike getInternalURL(), the canonical URL includes the fragment
	 *
	 * @see self::getLocalURL for the arguments.
	 * @return string The URL
	 * @since 1.18
	 */
	public function getCanonicalURL( $query = '', $query2 = false ) {
		$query = self::fixUrlQueryArgs( $query, $query2 );
		$url = wfExpandUrl( $this->getLocalURL( $query ) . $this->getFragmentForURL(), PROTO_CANONICAL );
		wfRunHooks( 'GetCanonicalURL', array( &$this, &$url, $query ) );
		return $url;
	}

	/**
	 * Get the edit URL for this Title
	 *
	 * @return string The URL, or a null string if this is an interwiki link
	 */
	public function getEditURL() {
		if ( $this->isExternal() ) {
			return '';
		}
		$s = $this->getLocalURL( 'action=edit' );

		return $s;
	}

	/**
	 * Is $wgUser watching this page?
	 *
	 * @deprecated since 1.20; use User::isWatched() instead.
	 * @return bool
	 */
	public function userIsWatching() {
		global $wgUser;

		if ( is_null( $this->mWatched ) ) {
			if ( NS_SPECIAL == $this->mNamespace || !$wgUser->isLoggedIn() ) {
				$this->mWatched = false;
			} else {
				$this->mWatched = $wgUser->isWatched( $this );
			}
		}
		return $this->mWatched;
	}

	/**
	 * Can $user perform $action on this page?
	 * This skips potentially expensive cascading permission checks
	 * as well as avoids expensive error formatting
	 *
	 * Suitable for use for nonessential UI controls in common cases, but
	 * _not_ for functional access control.
	 *
	 * May provide false positives, but should never provide a false negative.
	 *
	 * @param string $action Action that permission needs to be checked for
	 * @param User $user User to check (since 1.19); $wgUser will be used if not provided.
	 * @return bool
	 */
	public function quickUserCan( $action, $user = null ) {
		return $this->userCan( $action, $user, false );
	}

	/**
	 * Can $user perform $action on this page?
	 *
	 * @param string $action Action that permission needs to be checked for
	 * @param User $user User to check (since 1.19); $wgUser will be used if not
	 *   provided.
	 * @param bool $doExpensiveQueries Set this to false to avoid doing
	 *   unnecessary queries.
	 * @return bool
	 */
	public function userCan( $action, $user = null, $doExpensiveQueries = true ) {
		if ( !$user instanceof User ) {
			global $wgUser;
			$user = $wgUser;
		}

		return !count( $this->getUserPermissionsErrorsInternal(
			$action, $user, $doExpensiveQueries, true ) );
	}

	/**
	 * Can $user perform $action on this page?
	 *
	 * @todo FIXME: This *does not* check throttles (User::pingLimiter()).
	 *
	 * @param string $action Action that permission needs to be checked for
	 * @param User $user User to check
	 * @param bool $doExpensiveQueries Set this to false to avoid doing unnecessary
	 *   queries by skipping checks for cascading protections and user blocks.
	 * @param array $ignoreErrors Array of Strings Set this to a list of message keys
	 *   whose corresponding errors may be ignored.
	 * @return array Array of arguments to wfMessage to explain permissions problems.
	 */
	public function getUserPermissionsErrors( $action, $user, $doExpensiveQueries = true,
		$ignoreErrors = array()
	) {
		$errors = $this->getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries );

		// Remove the errors being ignored.
		foreach ( $errors as $index => $error ) {
			$error_key = is_array( $error ) ? $error[0] : $error;

			if ( in_array( $error_key, $ignoreErrors ) ) {
				unset( $errors[$index] );
			}
		}

		return $errors;
	}

	/**
	 * Permissions checks that fail most often, and which are easiest to test.
	 *
	 * @param string $action The action to check
	 * @param User $user User to check
	 * @param array $errors List of current errors
	 * @param bool $doExpensiveQueries Whether or not to perform expensive queries
	 * @param bool $short Short circuit on first error
	 *
	 * @return array List of errors
	 */
	private function checkQuickPermissions( $action, $user, $errors,
		$doExpensiveQueries, $short
	) {
		if ( !wfRunHooks( 'TitleQuickPermissions',
			array( $this, $user, $action, &$errors, $doExpensiveQueries, $short ) )
		) {
			return $errors;
		}

		if ( $action == 'create' ) {
			if (
				( $this->isTalkPage() && !$user->isAllowed( 'createtalk' ) ) ||
				( !$this->isTalkPage() && !$user->isAllowed( 'createpage' ) )
			) {
				$errors[] = $user->isAnon() ? array( 'nocreatetext' ) : array( 'nocreate-loggedin' );
			}
		} elseif ( $action == 'move' ) {
			if ( !$user->isAllowed( 'move-rootuserpages' )
					&& $this->mNamespace == NS_USER && !$this->isSubpage() ) {
				// Show user page-specific message only if the user can move other pages
				$errors[] = array( 'cant-move-user-page' );
			}

			// Check if user is allowed to move files if it's a file
			if ( $this->mNamespace == NS_FILE && !$user->isAllowed( 'movefile' ) ) {
				$errors[] = array( 'movenotallowedfile' );
			}

			// Check if user is allowed to move category pages if it's a category page
			if ( $this->mNamespace == NS_CATEGORY && !$user->isAllowed( 'move-categorypages' ) ) {
				$errors[] = array( 'cant-move-category-page' );
			}

			if ( !$user->isAllowed( 'move' ) ) {
				// User can't move anything
				$userCanMove = User::groupHasPermission( 'user', 'move' );
				$autoconfirmedCanMove = User::groupHasPermission( 'autoconfirmed', 'move' );
				if ( $user->isAnon() && ( $userCanMove || $autoconfirmedCanMove ) ) {
					// custom message if logged-in users without any special rights can move
					$errors[] = array( 'movenologintext' );
				} else {
					$errors[] = array( 'movenotallowed' );
				}
			}
		} elseif ( $action == 'move-target' ) {
			if ( !$user->isAllowed( 'move' ) ) {
				// User can't move anything
				$errors[] = array( 'movenotallowed' );
			} elseif ( !$user->isAllowed( 'move-rootuserpages' )
					&& $this->mNamespace == NS_USER && !$this->isSubpage() ) {
				// Show user page-specific message only if the user can move other pages
				$errors[] = array( 'cant-move-to-user-page' );
			} elseif ( !$user->isAllowed( 'move-categorypages' )
					&& $this->mNamespace == NS_CATEGORY ) {
				// Show category page-specific message only if the user can move other pages
				$errors[] = array( 'cant-move-to-category-page' );
			}
		} elseif ( !$user->isAllowed( $action ) ) {
			$errors[] = $this->missingPermissionError( $action, $short );
		}

		return $errors;
	}

	/**
	 * Add the resulting error code to the errors array
	 *
	 * @param array $errors List of current errors
	 * @param array $result Result of errors
	 *
	 * @return array List of errors
	 */
	private function resultToError( $errors, $result ) {
		if ( is_array( $result ) && count( $result ) && !is_array( $result[0] ) ) {
			// A single array representing an error
			$errors[] = $result;
		} elseif ( is_array( $result ) && is_array( $result[0] ) ) {
			// A nested array representing multiple errors
			$errors = array_merge( $errors, $result );
		} elseif ( $result !== '' && is_string( $result ) ) {
			// A string representing a message-id
			$errors[] = array( $result );
		} elseif ( $result === false ) {
			// a generic "We don't want them to do that"
			$errors[] = array( 'badaccess-group0' );
		}
		return $errors;
	}

	/**
	 * Check various permission hooks
	 *
	 * @param string $action The action to check
	 * @param User $user User to check
	 * @param array $errors List of current errors
	 * @param bool $doExpensiveQueries Whether or not to perform expensive queries
	 * @param bool $short Short circuit on first error
	 *
	 * @return array List of errors
	 */
	private function checkPermissionHooks( $action, $user, $errors, $doExpensiveQueries, $short ) {
		// Use getUserPermissionsErrors instead
		$result = '';
		if ( !wfRunHooks( 'userCan', array( &$this, &$user, $action, &$result ) ) ) {
			return $result ? array() : array( array( 'badaccess-group0' ) );
		}
		// Check getUserPermissionsErrors hook
		if ( !wfRunHooks( 'getUserPermissionsErrors', array( &$this, &$user, $action, &$result ) ) ) {
			$errors = $this->resultToError( $errors, $result );
		}
		// Check getUserPermissionsErrorsExpensive hook
		if (
			$doExpensiveQueries
			&& !( $short && count( $errors ) > 0 )
			&& !wfRunHooks( 'getUserPermissionsErrorsExpensive', array( &$this, &$user, $action, &$result ) )
		) {
			$errors = $this->resultToError( $errors, $result );
		}

		return $errors;
	}

	/**
	 * Check permissions on special pages & namespaces
	 *
	 * @param string $action The action to check
	 * @param User $user User to check
	 * @param array $errors List of current errors
	 * @param bool $doExpensiveQueries Whether or not to perform expensive queries
	 * @param bool $short Short circuit on first error
	 *
	 * @return array List of errors
	 */
	private function checkSpecialsAndNSPermissions( $action, $user, $errors,
		$doExpensiveQueries, $short
	) {
		# Only 'createaccount' can be performed on special pages,
		# which don't actually exist in the DB.
		if ( NS_SPECIAL == $this->mNamespace && $action !== 'createaccount' ) {
			$errors[] = array( 'ns-specialprotected' );
		}

		# Check $wgNamespaceProtection for restricted namespaces
		if ( $this->isNamespaceProtected( $user ) ) {
			$ns = $this->mNamespace == NS_MAIN ?
				wfMessage( 'nstab-main' )->text() : $this->getNsText();
			$errors[] = $this->mNamespace == NS_MEDIAWIKI ?
				array( 'protectedinterface', $action ) : array( 'namespaceprotected', $ns, $action );
		}

		return $errors;
	}

	/**
	 * Check CSS/JS sub-page permissions
	 *
	 * @param string $action The action to check
	 * @param User $user User to check
	 * @param array $errors List of current errors
	 * @param bool $doExpensiveQueries Whether or not to perform expensive queries
	 * @param bool $short Short circuit on first error
	 *
	 * @return array List of errors
	 */
	private function checkCSSandJSPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
		# Protect css/js subpages of user pages
		# XXX: this might be better using restrictions
		# XXX: right 'editusercssjs' is deprecated, for backward compatibility only
		if ( $action != 'patrol' && !$user->isAllowed( 'editusercssjs' ) ) {
			if ( preg_match( '/^' . preg_quote( $user->getName(), '/' ) . '\//', $this->mTextform ) ) {
				if ( $this->isCssSubpage() && !$user->isAllowedAny( 'editmyusercss', 'editusercss' ) ) {
					$errors[] = array( 'mycustomcssprotected', $action );
				} elseif ( $this->isJsSubpage() && !$user->isAllowedAny( 'editmyuserjs', 'edituserjs' ) ) {
					$errors[] = array( 'mycustomjsprotected', $action );
				}
			} else {
				if ( $this->isCssSubpage() && !$user->isAllowed( 'editusercss' ) ) {
					$errors[] = array( 'customcssprotected', $action );
				} elseif ( $this->isJsSubpage() && !$user->isAllowed( 'edituserjs' ) ) {
					$errors[] = array( 'customjsprotected', $action );
				}
			}
		}

		return $errors;
	}

	/**
	 * Check against page_restrictions table requirements on this
	 * page. The user must possess all required rights for this
	 * action.
	 *
	 * @param string $action The action to check
	 * @param User $user User to check
	 * @param array $errors List of current errors
	 * @param bool $doExpensiveQueries Whether or not to perform expensive queries
	 * @param bool $short Short circuit on first error
	 *
	 * @return array List of errors
	 */
	private function checkPageRestrictions( $action, $user, $errors, $doExpensiveQueries, $short ) {
		foreach ( $this->getRestrictions( $action ) as $right ) {
			// Backwards compatibility, rewrite sysop -> editprotected
			if ( $right == 'sysop' ) {
				$right = 'editprotected';
			}
			// Backwards compatibility, rewrite autoconfirmed -> editsemiprotected
			if ( $right == 'autoconfirmed' ) {
				$right = 'editsemiprotected';
			}
			if ( $right == '' ) {
				continue;
			}
			if ( !$user->isAllowed( $right ) ) {
				$errors[] = array( 'protectedpagetext', $right, $action );
			} elseif ( $this->mCascadeRestriction && !$user->isAllowed( 'protect' ) ) {
				$errors[] = array( 'protectedpagetext', 'protect', $action );
			}
		}

		return $errors;
	}

	/**
	 * Check restrictions on cascading pages.
	 *
	 * @param string $action The action to check
	 * @param User $user User to check
	 * @param array $errors List of current errors
	 * @param bool $doExpensiveQueries Whether or not to perform expensive queries
	 * @param bool $short Short circuit on first error
	 *
	 * @return array List of errors
	 */
	private function checkCascadingSourcesRestrictions( $action, $user, $errors,
		$doExpensiveQueries, $short
	) {
		if ( $doExpensiveQueries && !$this->isCssJsSubpage() ) {
			# We /could/ use the protection level on the source page, but it's
			# fairly ugly as we have to establish a precedence hierarchy for pages
			# included by multiple cascade-protected pages. So just restrict
			# it to people with 'protect' permission, as they could remove the
			# protection anyway.
			list( $cascadingSources, $restrictions ) = $this->getCascadeProtectionSources();
			# Cascading protection depends on more than this page...
			# Several cascading protected pages may include this page...
			# Check each cascading level
			# This is only for protection restrictions, not for all actions
			if ( isset( $restrictions[$action] ) ) {
				foreach ( $restrictions[$action] as $right ) {
					// Backwards compatibility, rewrite sysop -> editprotected
					if ( $right == 'sysop' ) {
						$right = 'editprotected';
					}
					// Backwards compatibility, rewrite autoconfirmed -> editsemiprotected
					if ( $right == 'autoconfirmed' ) {
						$right = 'editsemiprotected';
					}
					if ( $right != '' && !$user->isAllowedAll( 'protect', $right ) ) {
						$pages = '';
						foreach ( $cascadingSources as $page ) {
							$pages .= '* [[:' . $page->getPrefixedText() . "]]\n";
						}
						$errors[] = array( 'cascadeprotected', count( $cascadingSources ), $pages, $action );
					}
				}
			}
		}

		return $errors;
	}

	/**
	 * Check action permissions not already checked in checkQuickPermissions
	 *
	 * @param string $action The action to check
	 * @param User $user User to check
	 * @param array $errors List of current errors
	 * @param bool $doExpensiveQueries Whether or not to perform expensive queries
	 * @param bool $short Short circuit on first error
	 *
	 * @return array List of errors
	 */
	private function checkActionPermissions( $action, $user, $errors,
		$doExpensiveQueries, $short
	) {
		global $wgDeleteRevisionsLimit, $wgLang;

		if ( $action == 'protect' ) {
			if ( count( $this->getUserPermissionsErrorsInternal( 'edit',
				$user, $doExpensiveQueries, true ) )
			) {
				// If they can't edit, they shouldn't protect.
				$errors[] = array( 'protect-cantedit' );
			}
		} elseif ( $action == 'create' ) {
			$title_protection = $this->getTitleProtection();
			if ( $title_protection ) {
				if ( $title_protection['pt_create_perm'] == 'sysop' ) {
					$title_protection['pt_create_perm'] = 'editprotected'; // B/C
				}
				if ( $title_protection['pt_create_perm'] == 'autoconfirmed' ) {
					$title_protection['pt_create_perm'] = 'editsemiprotected'; // B/C
				}
				if ( $title_protection['pt_create_perm'] == ''
					|| !$user->isAllowed( $title_protection['pt_create_perm'] )
				) {
					$errors[] = array(
						'titleprotected',
						User::whoIs( $title_protection['pt_user'] ),
						$title_protection['pt_reason']
					);
				}
			}
		} elseif ( $action == 'move' ) {
			// Check for immobile pages
			if ( !MWNamespace::isMovable( $this->mNamespace ) ) {
				// Specific message for this case
				$errors[] = array( 'immobile-source-namespace', $this->getNsText() );
			} elseif ( !$this->isMovable() ) {
				// Less specific message for rarer cases
				$errors[] = array( 'immobile-source-page' );
			}
		} elseif ( $action == 'move-target' ) {
			if ( !MWNamespace::isMovable( $this->mNamespace ) ) {
				$errors[] = array( 'immobile-target-namespace', $this->getNsText() );
			} elseif ( !$this->isMovable() ) {
				$errors[] = array( 'immobile-target-page' );
			}
		} elseif ( $action == 'delete' ) {
			$tempErrors = $this->checkPageRestrictions( 'edit',
				$user, array(), $doExpensiveQueries, true );
			if ( !$tempErrors ) {
				$tempErrors = $this->checkCascadingSourcesRestrictions( 'edit',
					$user, $tempErrors, $doExpensiveQueries, true );
			}
			if ( $tempErrors ) {
				// If protection keeps them from editing, they shouldn't be able to delete.
				$errors[] = array( 'deleteprotected' );
			}
			if ( $doExpensiveQueries && $wgDeleteRevisionsLimit
				&& !$this->userCan( 'bigdelete', $user ) && $this->isBigDeletion()
			) {
				$errors[] = array( 'delete-toobig', $wgLang->formatNum( $wgDeleteRevisionsLimit ) );
			}
		}
		return $errors;
	}

	/**
	 * Check that the user isn't blocked from editing.
	 *
	 * @param string $action The action to check
	 * @param User $user User to check
	 * @param array $errors List of current errors
	 * @param bool $doExpensiveQueries Whether or not to perform expensive queries
	 * @param bool $short Short circuit on first error
	 *
	 * @return array List of errors
	 */
	private function checkUserBlock( $action, $user, $errors, $doExpensiveQueries, $short ) {
		// Account creation blocks handled at userlogin.
		// Unblocking handled in SpecialUnblock
		if ( !$doExpensiveQueries || in_array( $action, array( 'createaccount', 'unblock' ) ) ) {
			return $errors;
		}

		global $wgEmailConfirmToEdit;

		if ( $wgEmailConfirmToEdit && !$user->isEmailConfirmed() ) {
			$errors[] = array( 'confirmedittext' );
		}

		if ( ( $action == 'edit' || $action == 'create' ) && !$user->isBlockedFrom( $this ) ) {
			// Don't block the user from editing their own talk page unless they've been
			// explicitly blocked from that too.
		} elseif ( $user->isBlocked() && $user->mBlock->prevents( $action ) !== false ) {
			// @todo FIXME: Pass the relevant context into this function.
			$errors[] = $user->getBlock()->getPermissionsError( RequestContext::getMain() );
		}

		return $errors;
	}

	/**
	 * Check that the user is allowed to read this page.
	 *
	 * @param string $action The action to check
	 * @param User $user User to check
	 * @param array $errors List of current errors
	 * @param bool $doExpensiveQueries Whether or not to perform expensive queries
	 * @param bool $short Short circuit on first error
	 *
	 * @return array List of errors
	 */
	private function checkReadPermissions( $action, $user, $errors, $doExpensiveQueries, $short ) {
		global $wgWhitelistRead, $wgWhitelistReadRegexp;

		$whitelisted = false;
		if ( User::isEveryoneAllowed( 'read' ) ) {
			# Shortcut for public wikis, allows skipping quite a bit of code
			$whitelisted = true;
		} elseif ( $user->isAllowed( 'read' ) ) {
			# If the user is allowed to read pages, he is allowed to read all pages
			$whitelisted = true;
		} elseif ( $this->isSpecial( 'Userlogin' )
			|| $this->isSpecial( 'ChangePassword' )
			|| $this->isSpecial( 'PasswordReset' )
		) {
			# Always grant access to the login page.
			# Even anons need to be able to log in.
			$whitelisted = true;
		} elseif ( is_array( $wgWhitelistRead ) && count( $wgWhitelistRead ) ) {
			# Time to check the whitelist
			# Only do these checks is there's something to check against
			$name = $this->getPrefixedText();
			$dbName = $this->getPrefixedDBkey();

			// Check for explicit whitelisting with and without underscores
			if ( in_array( $name, $wgWhitelistRead, true ) || in_array( $dbName, $wgWhitelistRead, true ) ) {
				$whitelisted = true;
			} elseif ( $this->getNamespace() == NS_MAIN ) {
				# Old settings might have the title prefixed with
				# a colon for main-namespace pages
				if ( in_array( ':' . $name, $wgWhitelistRead ) ) {
					$whitelisted = true;
				}
			} elseif ( $this->isSpecialPage() ) {
				# If it's a special page, ditch the subpage bit and check again
				$name = $this->getDBkey();
				list( $name, /* $subpage */ ) = SpecialPageFactory::resolveAlias( $name );
				if ( $name ) {
					$pure = SpecialPage::getTitleFor( $name )->getPrefixedText();
					if ( in_array( $pure, $wgWhitelistRead, true ) ) {
						$whitelisted = true;
					}
				}
			}
		}

		if ( !$whitelisted && is_array( $wgWhitelistReadRegexp ) && !empty( $wgWhitelistReadRegexp ) ) {
			$name = $this->getPrefixedText();
			// Check for regex whitelisting
			foreach ( $wgWhitelistReadRegexp as $listItem ) {
				if ( preg_match( $listItem, $name ) ) {
					$whitelisted = true;
					break;
				}
			}
		}

		if ( !$whitelisted ) {
			# If the title is not whitelisted, give extensions a chance to do so...
			wfRunHooks( 'TitleReadWhitelist', array( $this, $user, &$whitelisted ) );
			if ( !$whitelisted ) {
				$errors[] = $this->missingPermissionError( $action, $short );
			}
		}

		return $errors;
	}

	/**
	 * Get a description array when the user doesn't have the right to perform
	 * $action (i.e. when User::isAllowed() returns false)
	 *
	 * @param string $action The action to check
	 * @param bool $short Short circuit on first error
	 * @return array List of errors
	 */
	private function missingPermissionError( $action, $short ) {
		// We avoid expensive display logic for quickUserCan's and such
		if ( $short ) {
			return array( 'badaccess-group0' );
		}

		$groups = array_map( array( 'User', 'makeGroupLinkWiki' ),
			User::getGroupsWithPermission( $action ) );

		if ( count( $groups ) ) {
			global $wgLang;
			return array(
				'badaccess-groups',
				$wgLang->commaList( $groups ),
				count( $groups )
			);
		} else {
			return array( 'badaccess-group0' );
		}
	}

	/**
	 * Can $user perform $action on this page? This is an internal function,
	 * which checks ONLY that previously checked by userCan (i.e. it leaves out
	 * checks on wfReadOnly() and blocks)
	 *
	 * @param string $action Action that permission needs to be checked for
	 * @param User $user User to check
	 * @param bool $doExpensiveQueries Set this to false to avoid doing unnecessary queries.
	 * @param bool $short Set this to true to stop after the first permission error.
	 * @return array Array of arrays of the arguments to wfMessage to explain permissions problems.
	 */
	protected function getUserPermissionsErrorsInternal( $action, $user,
		$doExpensiveQueries = true, $short = false
	) {
		wfProfileIn( __METHOD__ );

		# Read has special handling
		if ( $action == 'read' ) {
			$checks = array(
				'checkPermissionHooks',
				'checkReadPermissions',
			);
		# Don't call checkSpecialsAndNSPermissions or checkCSSandJSPermissions
		# here as it will lead to duplicate error messages. This is okay to do
		# since anywhere that checks for create will also check for edit, and
		# those checks are called for edit.
		} elseif ( $action == 'create' ) {
			$checks = array(
				'checkQuickPermissions',
				'checkPermissionHooks',
				'checkPageRestrictions',
				'checkCascadingSourcesRestrictions',
				'checkActionPermissions',
				'checkUserBlock'
			);
		} else {
			$checks = array(
				'checkQuickPermissions',
				'checkPermissionHooks',
				'checkSpecialsAndNSPermissions',
				'checkCSSandJSPermissions',
				'checkPageRestrictions',
				'checkCascadingSourcesRestrictions',
				'checkActionPermissions',
				'checkUserBlock'
			);
		}

		$errors = array();
		while ( count( $checks ) > 0 &&
				!( $short && count( $errors ) > 0 ) ) {
			$method = array_shift( $checks );
			$errors = $this->$method( $action, $user, $errors, $doExpensiveQueries, $short );
		}

		wfProfileOut( __METHOD__ );
		return $errors;
	}

	/**
	 * Get a filtered list of all restriction types supported by this wiki.
	 * @param bool $exists True to get all restriction types that apply to
	 * titles that do exist, False for all restriction types that apply to
	 * titles that do not exist
	 * @return array
	 */
	public static function getFilteredRestrictionTypes( $exists = true ) {
		global $wgRestrictionTypes;
		$types = $wgRestrictionTypes;
		if ( $exists ) {
			# Remove the create restriction for existing titles
			$types = array_diff( $types, array( 'create' ) );
		} else {
			# Only the create and upload restrictions apply to non-existing titles
			$types = array_intersect( $types, array( 'create', 'upload' ) );
		}
		return $types;
	}

	/**
	 * Returns restriction types for the current Title
	 *
	 * @return array Applicable restriction types
	 */
	public function getRestrictionTypes() {
		if ( $this->isSpecialPage() ) {
			return array();
		}

		$types = self::getFilteredRestrictionTypes( $this->exists() );

		if ( $this->getNamespace() != NS_FILE ) {
			# Remove the upload restriction for non-file titles
			$types = array_diff( $types, array( 'upload' ) );
		}

		wfRunHooks( 'TitleGetRestrictionTypes', array( $this, &$types ) );

		wfDebug( __METHOD__ . ': applicable restrictions to [[' .
			$this->getPrefixedText() . ']] are {' . implode( ',', $types ) . "}\n" );

		return $types;
	}

	/**
	 * Is this title subject to title protection?
	 * Title protection is the one applied against creation of such title.
	 *
	 * @return array|bool An associative array representing any existent title
	 *   protection, or false if there's none.
	 */
	private function getTitleProtection() {
		// Can't protect pages in special namespaces
		if ( $this->getNamespace() < 0 ) {
			return false;
		}

		// Can't protect pages that exist.
		if ( $this->exists() ) {
			return false;
		}

		if ( $this->mTitleProtection === null ) {
			$dbr = wfGetDB( DB_SLAVE );
			$res = $dbr->select(
				'protected_titles',
				array( 'pt_user', 'pt_reason', 'pt_expiry', 'pt_create_perm' ),
				array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
				__METHOD__
			);

			// fetchRow returns false if there are no rows.
			$this->mTitleProtection = $dbr->fetchRow( $res );
		}
		return $this->mTitleProtection;
	}

	/**
	 * Remove any title protection due to page existing
	 */
	public function deleteTitleProtection() {
		$dbw = wfGetDB( DB_MASTER );

		$dbw->delete(
			'protected_titles',
			array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
			__METHOD__
		);
		$this->mTitleProtection = false;
	}

	/**
	 * Is this page "semi-protected" - the *only* protection levels are listed
	 * in $wgSemiprotectedRestrictionLevels?
	 *
	 * @param string $action Action to check (default: edit)
	 * @return bool
	 */
	public function isSemiProtected( $action = 'edit' ) {
		global $wgSemiprotectedRestrictionLevels;

		$restrictions = $this->getRestrictions( $action );
		$semi = $wgSemiprotectedRestrictionLevels;
		if ( !$restrictions || !$semi ) {
			// Not protected, or all protection is full protection
			return false;
		}

		// Remap autoconfirmed to editsemiprotected for BC
		foreach ( array_keys( $semi, 'autoconfirmed' ) as $key ) {
			$semi[$key] = 'editsemiprotected';
		}
		foreach ( array_keys( $restrictions, 'autoconfirmed' ) as $key ) {
			$restrictions[$key] = 'editsemiprotected';
		}

		return !array_diff( $restrictions, $semi );
	}

	/**
	 * Does the title correspond to a protected article?
	 *
	 * @param string $action The action the page is protected from,
	 * by default checks all actions.
	 * @return bool
	 */
	public function isProtected( $action = '' ) {
		global $wgRestrictionLevels;

		$restrictionTypes = $this->getRestrictionTypes();

		# Special pages have inherent protection
		if ( $this->isSpecialPage() ) {
			return true;
		}

		# Check regular protection levels
		foreach ( $restrictionTypes as $type ) {
			if ( $action == $type || $action == '' ) {
				$r = $this->getRestrictions( $type );
				foreach ( $wgRestrictionLevels as $level ) {
					if ( in_array( $level, $r ) && $level != '' ) {
						return true;
					}
				}
			}
		}

		return false;
	}

	/**
	 * Determines if $user is unable to edit this page because it has been protected
	 * by $wgNamespaceProtection.
	 *
	 * @param User $user User object to check permissions
	 * @return bool
	 */
	public function isNamespaceProtected( User $user ) {
		global $wgNamespaceProtection;

		if ( isset( $wgNamespaceProtection[$this->mNamespace] ) ) {
			foreach ( (array)$wgNamespaceProtection[$this->mNamespace] as $right ) {
				if ( $right != '' && !$user->isAllowed( $right ) ) {
					return true;
				}
			}
		}
		return false;
	}

	/**
	 * Cascading protection: Return true if cascading restrictions apply to this page, false if not.
	 *
	 * @return bool If the page is subject to cascading restrictions.
	 */
	public function isCascadeProtected() {
		list( $sources, /* $restrictions */ ) = $this->getCascadeProtectionSources( false );
		return ( $sources > 0 );
	}

	/**
	 * Determines whether cascading protection sources have already been loaded from
	 * the database.
	 *
	 * @param bool $getPages True to check if the pages are loaded, or false to check
	 * if the status is loaded.
	 * @return bool Whether or not the specified information has been loaded
	 * @since 1.23
	 */
	public function areCascadeProtectionSourcesLoaded( $getPages = true ) {
		return $getPages ? $this->mCascadeSources !== null : $this->mHasCascadingRestrictions !== null;
	}

	/**
	 * Cascading protection: Get the source of any cascading restrictions on this page.
	 *
	 * @param bool $getPages Whether or not to retrieve the actual pages
	 *        that the restrictions have come from and the actual restrictions
	 *        themselves.
	 * @return array Two elements: First is an array of Title objects of the
	 *        pages from which cascading restrictions have come, false for
	 *        none, or true if such restrictions exist but $getPages was not
	 *        set. Second is an array like that returned by
	 *        Title::getAllRestrictions(), or an empty array if $getPages is
	 *        false.
	 */
	public function getCascadeProtectionSources( $getPages = true ) {
		global $wgContLang;
		$pagerestrictions = array();

		if ( $this->mCascadeSources !== null && $getPages ) {
			return array( $this->mCascadeSources, $this->mCascadingRestrictions );
		} elseif ( $this->mHasCascadingRestrictions !== null && !$getPages ) {
			return array( $this->mHasCascadingRestrictions, $pagerestrictions );
		}

		wfProfileIn( __METHOD__ );

		$dbr = wfGetDB( DB_SLAVE );

		if ( $this->getNamespace() == NS_FILE ) {
			$tables = array( 'imagelinks', 'page_restrictions' );
			$where_clauses = array(
				'il_to' => $this->getDBkey(),
				'il_from=pr_page',
				'pr_cascade' => 1
			);
		} else {
			$tables = array( 'templatelinks', 'page_restrictions' );
			$where_clauses = array(
				'tl_namespace' => $this->getNamespace(),
				'tl_title' => $this->getDBkey(),
				'tl_from=pr_page',
				'pr_cascade' => 1
			);
		}

		if ( $getPages ) {
			$cols = array( 'pr_page', 'page_namespace', 'page_title',
				'pr_expiry', 'pr_type', 'pr_level' );
			$where_clauses[] = 'page_id=pr_page';
			$tables[] = 'page';
		} else {
			$cols = array( 'pr_expiry' );
		}

		$res = $dbr->select( $tables, $cols, $where_clauses, __METHOD__ );

		$sources = $getPages ? array() : false;
		$now = wfTimestampNow();
		$purgeExpired = false;

		foreach ( $res as $row ) {
			$expiry = $wgContLang->formatExpiry( $row->pr_expiry, TS_MW );
			if ( $expiry > $now ) {
				if ( $getPages ) {
					$page_id = $row->pr_page;
					$page_ns = $row->page_namespace;
					$page_title = $row->page_title;
					$sources[$page_id] = Title::makeTitle( $page_ns, $page_title );
					# Add groups needed for each restriction type if its not already there
					# Make sure this restriction type still exists

					if ( !isset( $pagerestrictions[$row->pr_type] ) ) {
						$pagerestrictions[$row->pr_type] = array();
					}

					if (
						isset( $pagerestrictions[$row->pr_type] )
						&& !in_array( $row->pr_level, $pagerestrictions[$row->pr_type] )
					) {
						$pagerestrictions[$row->pr_type][] = $row->pr_level;
					}
				} else {
					$sources = true;
				}
			} else {
				// Trigger lazy purge of expired restrictions from the db
				$purgeExpired = true;
			}
		}
		if ( $purgeExpired ) {
			Title::purgeExpiredRestrictions();
		}

		if ( $getPages ) {
			$this->mCascadeSources = $sources;
			$this->mCascadingRestrictions = $pagerestrictions;
		} else {
			$this->mHasCascadingRestrictions = $sources;
		}

		wfProfileOut( __METHOD__ );
		return array( $sources, $pagerestrictions );
	}

	/**
	 * Accessor for mRestrictionsLoaded
	 *
	 * @return bool Whether or not the page's restrictions have already been
	 * loaded from the database
	 * @since 1.23
	 */
	public function areRestrictionsLoaded() {
		return $this->mRestrictionsLoaded;
	}

	/**
	 * Accessor/initialisation for mRestrictions
	 *
	 * @param string $action Action that permission needs to be checked for
	 * @return array Restriction levels needed to take the action. All levels
	 *     are required.
	 */
	public function getRestrictions( $action ) {
		if ( !$this->mRestrictionsLoaded ) {
			$this->loadRestrictions();
		}
		return isset( $this->mRestrictions[$action] )
				? $this->mRestrictions[$action]
				: array();
	}

	/**
	 * Accessor/initialisation for mRestrictions
	 *
	 * @return array Keys are actions, values are arrays as returned by
	 *     Title::getRestrictions()
	 * @since 1.23
	 */
	public function getAllRestrictions() {
		if ( !$this->mRestrictionsLoaded ) {
			$this->loadRestrictions();
		}
		return $this->mRestrictions;
	}

	/**
	 * Get the expiry time for the restriction against a given action
	 *
	 * @param string $action
	 * @return string|bool 14-char timestamp, or 'infinity' if the page is protected forever
	 *     or not protected at all, or false if the action is not recognised.
	 */
	public function getRestrictionExpiry( $action ) {
		if ( !$this->mRestrictionsLoaded ) {
			$this->loadRestrictions();
		}
		return isset( $this->mRestrictionsExpiry[$action] ) ? $this->mRestrictionsExpiry[$action] : false;
	}

	/**
	 * Returns cascading restrictions for the current article
	 *
	 * @return bool
	 */
	function areRestrictionsCascading() {
		if ( !$this->mRestrictionsLoaded ) {
			$this->loadRestrictions();
		}

		return $this->mCascadeRestriction;
	}

	/**
	 * Loads a string into mRestrictions array
	 *
	 * @param ResultWrapper $res Resource restrictions as an SQL result.
	 * @param string $oldFashionedRestrictions Comma-separated list of page
	 *        restrictions from page table (pre 1.10)
	 */
	private function loadRestrictionsFromResultWrapper( $res, $oldFashionedRestrictions = null ) {
		$rows = array();

		foreach ( $res as $row ) {
			$rows[] = $row;
		}

		$this->loadRestrictionsFromRows( $rows, $oldFashionedRestrictions );
	}

	/**
	 * Compiles list of active page restrictions from both page table (pre 1.10)
	 * and page_restrictions table for this existing page.
	 * Public for usage by LiquidThreads.
	 *
	 * @param array $rows Array of db result objects
	 * @param string $oldFashionedRestrictions Comma-separated list of page
	 *   restrictions from page table (pre 1.10)
	 */
	public function loadRestrictionsFromRows( $rows, $oldFashionedRestrictions = null ) {
		global $wgContLang;
		$dbr = wfGetDB( DB_SLAVE );

		$restrictionTypes = $this->getRestrictionTypes();

		foreach ( $restrictionTypes as $type ) {
			$this->mRestrictions[$type] = array();
			$this->mRestrictionsExpiry[$type] = $wgContLang->formatExpiry( '', TS_MW );
		}

		$this->mCascadeRestriction = false;

		# Backwards-compatibility: also load the restrictions from the page record (old format).

		if ( $oldFashionedRestrictions === null ) {
			$oldFashionedRestrictions = $dbr->selectField( 'page', 'page_restrictions',
				array( 'page_id' => $this->getArticleID() ), __METHOD__ );
		}

		if ( $oldFashionedRestrictions != '' ) {

			foreach ( explode( ':', trim( $oldFashionedRestrictions ) ) as $restrict ) {
				$temp = explode( '=', trim( $restrict ) );
				if ( count( $temp ) == 1 ) {
					// old old format should be treated as edit/move restriction
					$this->mRestrictions['edit'] = explode( ',', trim( $temp[0] ) );
					$this->mRestrictions['move'] = explode( ',', trim( $temp[0] ) );
				} else {
					$restriction = trim( $temp[1] );
					if ( $restriction != '' ) { //some old entries are empty
						$this->mRestrictions[$temp[0]] = explode( ',', $restriction );
					}
				}
			}

			$this->mOldRestrictions = true;

		}

		if ( count( $rows ) ) {
			# Current system - load second to make them override.
			$now = wfTimestampNow();
			$purgeExpired = false;

			# Cycle through all the restrictions.
			foreach ( $rows as $row ) {

				// Don't take care of restrictions types that aren't allowed
				if ( !in_array( $row->pr_type, $restrictionTypes ) ) {
					continue;
				}

				// This code should be refactored, now that it's being used more generally,
				// But I don't really see any harm in leaving it in Block for now -werdna
				$expiry = $wgContLang->formatExpiry( $row->pr_expiry, TS_MW );

				// Only apply the restrictions if they haven't expired!
				if ( !$expiry || $expiry > $now ) {
					$this->mRestrictionsExpiry[$row->pr_type] = $expiry;
					$this->mRestrictions[$row->pr_type] = explode( ',', trim( $row->pr_level ) );

					$this->mCascadeRestriction |= $row->pr_cascade;
				} else {
					// Trigger a lazy purge of expired restrictions
					$purgeExpired = true;
				}
			}

			if ( $purgeExpired ) {
				Title::purgeExpiredRestrictions();
			}
		}

		$this->mRestrictionsLoaded = true;
	}

	/**
	 * Load restrictions from the page_restrictions table
	 *
	 * @param string $oldFashionedRestrictions Comma-separated list of page
	 *   restrictions from page table (pre 1.10)
	 */
	public function loadRestrictions( $oldFashionedRestrictions = null ) {
		global $wgContLang;
		if ( !$this->mRestrictionsLoaded ) {
			if ( $this->exists() ) {
				$dbr = wfGetDB( DB_SLAVE );

				$res = $dbr->select(
					'page_restrictions',
					array( 'pr_type', 'pr_expiry', 'pr_level', 'pr_cascade' ),
					array( 'pr_page' => $this->getArticleID() ),
					__METHOD__
				);

				$this->loadRestrictionsFromResultWrapper( $res, $oldFashionedRestrictions );
			} else {
				$title_protection = $this->getTitleProtection();

				if ( $title_protection ) {
					$now = wfTimestampNow();
					$expiry = $wgContLang->formatExpiry( $title_protection['pt_expiry'], TS_MW );

					if ( !$expiry || $expiry > $now ) {
						// Apply the restrictions
						$this->mRestrictionsExpiry['create'] = $expiry;
						$this->mRestrictions['create'] = explode( ',', trim( $title_protection['pt_create_perm'] ) );
					} else { // Get rid of the old restrictions
						Title::purgeExpiredRestrictions();
						$this->mTitleProtection = false;
					}
				} else {
					$this->mRestrictionsExpiry['create'] = $wgContLang->formatExpiry( '', TS_MW );
				}
				$this->mRestrictionsLoaded = true;
			}
		}
	}

	/**
	 * Flush the protection cache in this object and force reload from the database.
	 * This is used when updating protection from WikiPage::doUpdateRestrictions().
	 */
	public function flushRestrictions() {
		$this->mRestrictionsLoaded = false;
		$this->mTitleProtection = null;
	}

	/**
	 * Purge expired restrictions from the page_restrictions table
	 */
	static function purgeExpiredRestrictions() {
		if ( wfReadOnly() ) {
			return;
		}

		$method = __METHOD__;
		$dbw = wfGetDB( DB_MASTER );
		$dbw->onTransactionIdle( function () use ( $dbw, $method ) {
			$dbw->delete(
				'page_restrictions',
				array( 'pr_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
				$method
			);
			$dbw->delete(
				'protected_titles',
				array( 'pt_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
				$method
			);
		} );
	}

	/**
	 * Does this have subpages?  (Warning, usually requires an extra DB query.)
	 *
	 * @return bool
	 */
	public function hasSubpages() {
		if ( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
			# Duh
			return false;
		}

		# We dynamically add a member variable for the purpose of this method
		# alone to cache the result.  There's no point in having it hanging
		# around uninitialized in every Title object; therefore we only add it
		# if needed and don't declare it statically.
		if ( $this->mHasSubpages === null ) {
			$this->mHasSubpages = false;
			$subpages = $this->getSubpages( 1 );
			if ( $subpages instanceof TitleArray ) {
				$this->mHasSubpages = (bool)$subpages->count();
			}
		}

		return $this->mHasSubpages;
	}

	/**
	 * Get all subpages of this page.
	 *
	 * @param int $limit Maximum number of subpages to fetch; -1 for no limit
	 * @return TitleArray|array TitleArray, or empty array if this page's namespace
	 *  doesn't allow subpages
	 */
	public function getSubpages( $limit = -1 ) {
		if ( !MWNamespace::hasSubpages( $this->getNamespace() ) ) {
			return array();
		}

		$dbr = wfGetDB( DB_SLAVE );
		$conds['page_namespace'] = $this->getNamespace();
		$conds[] = 'page_title ' . $dbr->buildLike( $this->getDBkey() . '/', $dbr->anyString() );
		$options = array();
		if ( $limit > -1 ) {
			$options['LIMIT'] = $limit;
		}
		$this->mSubpages = TitleArray::newFromResult(
			$dbr->select( 'page',
				array( 'page_id', 'page_namespace', 'page_title', 'page_is_redirect' ),
				$conds,
				__METHOD__,
				$options
			)
		);
		return $this->mSubpages;
	}

	/**
	 * Is there a version of this page in the deletion archive?
	 *
	 * @return int The number of archived revisions
	 */
	public function isDeleted() {
		if ( $this->getNamespace() < 0 ) {
			$n = 0;
		} else {
			$dbr = wfGetDB( DB_SLAVE );

			$n = $dbr->selectField( 'archive', 'COUNT(*)',
				array( 'ar_namespace' => $this->getNamespace(), 'ar_title' => $this->getDBkey() ),
				__METHOD__
			);
			if ( $this->getNamespace() == NS_FILE ) {
				$n += $dbr->selectField( 'filearchive', 'COUNT(*)',
					array( 'fa_name' => $this->getDBkey() ),
					__METHOD__
				);
			}
		}
		return (int)$n;
	}

	/**
	 * Is there a version of this page in the deletion archive?
	 *
	 * @return bool
	 */
	public function isDeletedQuick() {
		if ( $this->getNamespace() < 0 ) {
			return false;
		}
		$dbr = wfGetDB( DB_SLAVE );
		$deleted = (bool)$dbr->selectField( 'archive', '1',
			array( 'ar_namespace' => $this->getNamespace(), 'ar_title' => $this->getDBkey() ),
			__METHOD__
		);
		if ( !$deleted && $this->getNamespace() == NS_FILE ) {
			$deleted = (bool)$dbr->selectField( 'filearchive', '1',
				array( 'fa_name' => $this->getDBkey() ),
				__METHOD__
			);
		}
		return $deleted;
	}

	/**
	 * Get the article ID for this Title from the link cache,
	 * adding it if necessary
	 *
	 * @param int $flags A bit field; may be Title::GAID_FOR_UPDATE to select
	 *  for update
	 * @return int The ID
	 */
	public function getArticleID( $flags = 0 ) {
		if ( $this->getNamespace() < 0 ) {
			$this->mArticleID = 0;
			return $this->mArticleID;
		}
		$linkCache = LinkCache::singleton();
		if ( $flags & self::GAID_FOR_UPDATE ) {
			$oldUpdate = $linkCache->forUpdate( true );
			$linkCache->clearLink( $this );
			$this->mArticleID = $linkCache->addLinkObj( $this );
			$linkCache->forUpdate( $oldUpdate );
		} else {
			if ( -1 == $this->mArticleID ) {
				$this->mArticleID = $linkCache->addLinkObj( $this );
			}
		}
		return $this->mArticleID;
	}

	/**
	 * Is this an article that is a redirect page?
	 * Uses link cache, adding it if necessary
	 *
	 * @param int $flags A bit field; may be Title::GAID_FOR_UPDATE to select for update
	 * @return bool
	 */
	public function isRedirect( $flags = 0 ) {
		if ( !is_null( $this->mRedirect ) ) {
			return $this->mRedirect;
		}
		# Calling getArticleID() loads the field from cache as needed
		if ( !$this->getArticleID( $flags ) ) {
			$this->mRedirect = false;
			return $this->mRedirect;
		}

		$linkCache = LinkCache::singleton();
		$cached = $linkCache->getGoodLinkFieldObj( $this, 'redirect' );
		if ( $cached === null ) {
			# Trust LinkCache's state over our own
			# LinkCache is telling us that the page doesn't exist, despite there being cached
			# data relating to an existing page in $this->mArticleID. Updaters should clear
			# LinkCache as appropriate, or use $flags = Title::GAID_FOR_UPDATE. If that flag is
			# set, then LinkCache will definitely be up to date here, since getArticleID() forces
			# LinkCache to refresh its data from the master.
			$this->mRedirect = false;
			return $this->mRedirect;
		}

		$this->mRedirect = (bool)$cached;

		return $this->mRedirect;
	}

	/**
	 * What is the length of this page?
	 * Uses link cache, adding it if necessary
	 *
	 * @param int $flags A bit field; may be Title::GAID_FOR_UPDATE to select for update
	 * @return int
	 */
	public function getLength( $flags = 0 ) {
		if ( $this->mLength != -1 ) {
			return $this->mLength;
		}
		# Calling getArticleID() loads the field from cache as needed
		if ( !$this->getArticleID( $flags ) ) {
			$this->mLength = 0;
			return $this->mLength;
		}
		$linkCache = LinkCache::singleton();
		$cached = $linkCache->getGoodLinkFieldObj( $this, 'length' );
		if ( $cached === null ) {
			# Trust LinkCache's state over our own, as for isRedirect()
			$this->mLength = 0;
			return $this->mLength;
		}

		$this->mLength = intval( $cached );

		return $this->mLength;
	}

	/**
	 * What is the page_latest field for this page?
	 *
	 * @param int $flags A bit field; may be Title::GAID_FOR_UPDATE to select for update
	 * @return int Int or 0 if the page doesn't exist
	 */
	public function getLatestRevID( $flags = 0 ) {
		if ( !( $flags & Title::GAID_FOR_UPDATE ) && $this->mLatestID !== false ) {
			return intval( $this->mLatestID );
		}
		# Calling getArticleID() loads the field from cache as needed
		if ( !$this->getArticleID( $flags ) ) {
			$this->mLatestID = 0;
			return $this->mLatestID;
		}
		$linkCache = LinkCache::singleton();
		$linkCache->addLinkObj( $this );
		$cached = $linkCache->getGoodLinkFieldObj( $this, 'revision' );
		if ( $cached === null ) {
			# Trust LinkCache's state over our own, as for isRedirect()
			$this->mLatestID = 0;
			return $this->mLatestID;
		}

		$this->mLatestID = intval( $cached );

		return $this->mLatestID;
	}

	/**
	 * This clears some fields in this object, and clears any associated
	 * keys in the "bad links" section of the link cache.
	 *
	 * - This is called from WikiPage::doEdit() and WikiPage::insertOn() to allow
	 * loading of the new page_id. It's also called from
	 * WikiPage::doDeleteArticleReal()
	 *
	 * @param int $newid The new Article ID
	 */
	public function resetArticleID( $newid ) {
		$linkCache = LinkCache::singleton();
		$linkCache->clearLink( $this );

		if ( $newid === false ) {
			$this->mArticleID = -1;
		} else {
			$this->mArticleID = intval( $newid );
		}
		$this->mRestrictionsLoaded = false;
		$this->mRestrictions = array();
		$this->mRedirect = null;
		$this->mLength = -1;
		$this->mLatestID = false;
		$this->mContentModel = false;
		$this->mEstimateRevisions = null;
		$this->mPageLanguage = false;
		$this->mDbPageLanguage = null;
		$this->mIsBigDeletion = null;
	}

	/**
	 * Capitalize a text string for a title if it belongs to a namespace that capitalizes
	 *
	 * @param string $text Containing title to capitalize
	 * @param int $ns Namespace index, defaults to NS_MAIN
	 * @return string Containing capitalized title
	 */
	public static function capitalize( $text, $ns = NS_MAIN ) {
		global $wgContLang;

		if ( MWNamespace::isCapitalized( $ns ) ) {
			return $wgContLang->ucfirst( $text );
		} else {
			return $text;
		}
	}

	/**
	 * Secure and split - main initialisation function for this object
	 *
	 * Assumes that mDbkeyform has been set, and is urldecoded
	 * and uses underscores, but not otherwise munged.  This function
	 * removes illegal characters, splits off the interwiki and
	 * namespace prefixes, sets the other forms, and canonicalizes
	 * everything.
	 *
	 * @return bool True on success
	 */
	private function secureAndSplit() {
		# Initialisation
		$this->mInterwiki = '';
		$this->mFragment = '';
		$this->mNamespace = $this->mDefaultNamespace; # Usually NS_MAIN

		$dbkey = $this->mDbkeyform;

		try {
			// @note: splitTitleString() is a temporary hack to allow MediaWikiTitleCodec to share
			//        the parsing code with Title, while avoiding massive refactoring.
			// @todo: get rid of secureAndSplit, refactor parsing code.
			$titleParser = self::getTitleParser();
			$parts = $titleParser->splitTitleString( $dbkey, $this->getDefaultNamespace() );
		} catch ( MalformedTitleException $ex ) {
			return false;
		}

		# Fill fields
		$this->setFragment( '#' . $parts['fragment'] );
		$this->mInterwiki = $parts['interwiki'];
		$this->mLocalInterwiki = $parts['local_interwiki'];
		$this->mNamespace = $parts['namespace'];
		$this->mUserCaseDBKey = $parts['user_case_dbkey'];

		$this->mDbkeyform = $parts['dbkey'];
		$this->mUrlform = wfUrlencode( $this->mDbkeyform );
		$this->mTextform = str_replace( '_', ' ', $this->mDbkeyform );

		# We already know that some pages won't be in the database!
		if ( $this->isExternal() || $this->mNamespace == NS_SPECIAL ) {
			$this->mArticleID = 0;
		}

		return true;
	}

	/**
	 * Get an array of Title objects linking to this Title
	 * Also stores the IDs in the link cache.
	 *
	 * WARNING: do not use this function on arbitrary user-supplied titles!
	 * On heavily-used templates it will max out the memory.
	 *
	 * @param array $options May be FOR UPDATE
	 * @param string $table Table name
	 * @param string $prefix Fields prefix
	 * @return Title[] Array of Title objects linking here
	 */
	public function getLinksTo( $options = array(), $table = 'pagelinks', $prefix = 'pl' ) {
		if ( count( $options ) > 0 ) {
			$db = wfGetDB( DB_MASTER );
		} else {
			$db = wfGetDB( DB_SLAVE );
		}

		$res = $db->select(
			array( 'page', $table ),
			self::getSelectFields(),
			array(
				"{$prefix}_from=page_id",
				"{$prefix}_namespace" => $this->getNamespace(),
				"{$prefix}_title" => $this->getDBkey() ),
			__METHOD__,
			$options
		);

		$retVal = array();
		if ( $res->numRows() ) {
			$linkCache = LinkCache::singleton();
			foreach ( $res as $row ) {
				$titleObj = Title::makeTitle( $row->page_namespace, $row->page_title );
				if ( $titleObj ) {
					$linkCache->addGoodLinkObjFromRow( $titleObj, $row );
					$retVal[] = $titleObj;
				}
			}
		}
		return $retVal;
	}

	/**
	 * Get an array of Title objects using this Title as a template
	 * Also stores the IDs in the link cache.
	 *
	 * WARNING: do not use this function on arbitrary user-supplied titles!
	 * On heavily-used templates it will max out the memory.
	 *
	 * @param array $options May be FOR UPDATE
	 * @return Title[] Array of Title the Title objects linking here
	 */
	public function getTemplateLinksTo( $options = array() ) {
		return $this->getLinksTo( $options, 'templatelinks', 'tl' );
	}

	/**
	 * Get an array of Title objects linked from this Title
	 * Also stores the IDs in the link cache.
	 *
	 * WARNING: do not use this function on arbitrary user-supplied titles!
	 * On heavily-used templates it will max out the memory.
	 *
	 * @param array $options May be FOR UPDATE
	 * @param string $table Table name
	 * @param string $prefix Fields prefix
	 * @return array Array of Title objects linking here
	 */
	public function getLinksFrom( $options = array(), $table = 'pagelinks', $prefix = 'pl' ) {
		global $wgContentHandlerUseDB;

		$id = $this->getArticleID();

		# If the page doesn't exist; there can't be any link from this page
		if ( !$id ) {
			return array();
		}

		if ( count( $options ) > 0 ) {
			$db = wfGetDB( DB_MASTER );
		} else {
			$db = wfGetDB( DB_SLAVE );
		}

		$namespaceFiled = "{$prefix}_namespace";
		$titleField = "{$prefix}_title";

		$fields = array(
			$namespaceFiled,
			$titleField,
			'page_id',
			'page_len',
			'page_is_redirect',
			'page_latest'
		);

		if ( $wgContentHandlerUseDB ) {
			$fields[] = 'page_content_model';
		}

		$res = $db->select(
			array( $table, 'page' ),
			$fields,
			array( "{$prefix}_from" => $id ),
			__METHOD__,
			$options,
			array( 'page' => array(
				'LEFT JOIN',
				array( "page_namespace=$namespaceFiled", "page_title=$titleField" )
			) )
		);

		$retVal = array();
		if ( $res->numRows() ) {
			$linkCache = LinkCache::singleton();
			foreach ( $res as $row ) {
				$titleObj = Title::makeTitle( $row->$namespaceFiled, $row->$titleField );
				if ( $titleObj ) {
					if ( $row->page_id ) {
						$linkCache->addGoodLinkObjFromRow( $titleObj, $row );
					} else {
						$linkCache->addBadLinkObj( $titleObj );
					}
					$retVal[] = $titleObj;
				}
			}
		}
		return $retVal;
	}

	/**
	 * Get an array of Title objects used on this Title as a template
	 * Also stores the IDs in the link cache.
	 *
	 * WARNING: do not use this function on arbitrary user-supplied titles!
	 * On heavily-used templates it will max out the memory.
	 *
	 * @param array $options May be FOR UPDATE
	 * @return Title[] Array of Title the Title objects used here
	 */
	public function getTemplateLinksFrom( $options = array() ) {
		return $this->getLinksFrom( $options, 'templatelinks', 'tl' );
	}

	/**
	 * Get an array of Title objects referring to non-existent articles linked
	 * from this page.
	 *
	 * @todo check if needed (used only in SpecialBrokenRedirects.php, and
	 *   should use redirect table in this case).
	 * @return Title[] Array of Title the Title objects
	 */
	public function getBrokenLinksFrom() {
		if ( $this->getArticleID() == 0 ) {
			# All links from article ID 0 are false positives
			return array();
		}

		$dbr = wfGetDB( DB_SLAVE );
		$res = $dbr->select(
			array( 'page', 'pagelinks' ),
			array( 'pl_namespace', 'pl_title' ),
			array(
				'pl_from' => $this->getArticleID(),
				'page_namespace IS NULL'
			),
			__METHOD__, array(),
			array(
				'page' => array(
					'LEFT JOIN',
					array( 'pl_namespace=page_namespace', 'pl_title=page_title' )
				)
			)
		);

		$retVal = array();
		foreach ( $res as $row ) {
			$retVal[] = Title::makeTitle( $row->pl_namespace, $row->pl_title );
		}
		return $retVal;
	}

	/**
	 * Get a list of URLs to purge from the Squid cache when this
	 * page changes
	 *
	 * @return string[] Array of String the URLs
	 */
	public function getSquidURLs() {
		$urls = array(
			$this->getInternalURL(),
			$this->getInternalURL( 'action=history' )
		);

		$pageLang = $this->getPageLanguage();
		if ( $pageLang->hasVariants() ) {
			$variants = $pageLang->getVariants();
			foreach ( $variants as $vCode ) {
				$urls[] = $this->getInternalURL( '', $vCode );
			}
		}

		// If we are looking at a css/js user subpage, purge the action=raw.
		if ( $this->isJsSubpage() ) {
			$urls[] = $this->getInternalUrl( 'action=raw&ctype=text/javascript' );
		} elseif ( $this->isCssSubpage() ) {
			$urls[] = $this->getInternalUrl( 'action=raw&ctype=text/css' );
		}

		wfRunHooks( 'TitleSquidURLs', array( $this, &$urls ) );
		return $urls;
	}

	/**
	 * Purge all applicable Squid URLs
	 */
	public function purgeSquid() {
		global $wgUseSquid;
		if ( $wgUseSquid ) {
			$urls = $this->getSquidURLs();
			$u = new SquidUpdate( $urls );
			$u->doUpdate();
		}
	}

	/**
	 * Move this page without authentication
	 *
	 * @param Title $nt The new page Title
	 * @return array|bool True on success, getUserPermissionsErrors()-like array on failure
	 */
	public function moveNoAuth( &$nt ) {
		return $this->moveTo( $nt, false );
	}

	/**
	 * Check whether a given move operation would be valid.
	 * Returns true if ok, or a getUserPermissionsErrors()-like array otherwise
	 *
	 * @todo move this into MovePage
	 * @param Title $nt The new title
	 * @param bool $auth Indicates whether $wgUser's permissions
	 *  should be checked
	 * @param string $reason Is the log summary of the move, used for spam checking
	 * @return array|bool True on success, getUserPermissionsErrors()-like array on failure
	 */
	public function isValidMoveOperation( &$nt, $auth = true, $reason = '' ) {
		global $wgUser, $wgContentHandlerUseDB;

		$errors = array();
		if ( !$nt ) {
			// Normally we'd add this to $errors, but we'll get
			// lots of syntax errors if $nt is not an object
			return array( array( 'badtitletext' ) );
		}
		if ( $this->equals( $nt ) ) {
			$errors[] = array( 'selfmove' );
		}
		if ( !$this->isMovable() ) {
			$errors[] = array( 'immobile-source-namespace', $this->getNsText() );
		}
		if ( $nt->isExternal() ) {
			$errors[] = array( 'immobile-target-namespace-iw' );
		}
		if ( !$nt->isMovable() ) {
			$errors[] = array( 'immobile-target-namespace', $nt->getNsText() );
		}

		$oldid = $this->getArticleID();
		$newid = $nt->getArticleID();

		if ( strlen( $nt->getDBkey() ) < 1 ) {
			$errors[] = array( 'articleexists' );
		}
		if (
			( $this->getDBkey() == '' ) ||
			( !$oldid ) ||
			( $nt->getDBkey() == '' )
		) {
			$errors[] = array( 'badarticleerror' );
		}

		// Content model checks
		if ( !$wgContentHandlerUseDB &&
				$this->getContentModel() !== $nt->getContentModel() ) {
			// can't move a page if that would change the page's content model
			$errors[] = array(
				'bad-target-model',
				ContentHandler::getLocalizedName( $this->getContentModel() ),
				ContentHandler::getLocalizedName( $nt->getContentModel() )
			);
		}

		// Image-specific checks
		if ( $this->getNamespace() == NS_FILE ) {
			$errors = array_merge( $errors, $this->validateFileMoveOperation( $nt ) );
		}

		if ( $nt->getNamespace() == NS_FILE && $this->getNamespace() != NS_FILE ) {
			$errors[] = array( 'nonfile-cannot-move-to-file' );
		}

		if ( $auth ) {
			$errors = wfMergeErrorArrays( $errors,
				$this->getUserPermissionsErrors( 'move', $wgUser ),
				$this->getUserPermissionsErrors( 'edit', $wgUser ),
				$nt->getUserPermissionsErrors( 'move-target', $wgUser ),
				$nt->getUserPermissionsErrors( 'edit', $wgUser ) );
		}

		$match = EditPage::matchSummarySpamRegex( $reason );
		if ( $match !== false ) {
			// This is kind of lame, won't display nice
			$errors[] = array( 'spamprotectiontext' );
		}

		$err = null;
		if ( !wfRunHooks( 'AbortMove', array( $this, $nt, $wgUser, &$err, $reason ) ) ) {
			$errors[] = array( 'hookaborted', $err );
		}

		# The move is allowed only if (1) the target doesn't exist, or
		# (2) the target is a redirect to the source, and has no history
		# (so we can undo bad moves right after they're done).

		if ( 0 != $newid ) { # Target exists; check for validity
			if ( !$this->isValidMoveTarget( $nt ) ) {
				$errors[] = array( 'articleexists' );
			}
		} else {
			$tp = $nt->getTitleProtection();
			$right = $tp['pt_create_perm'];
			if ( $right == 'sysop' ) {
				$right = 'editprotected'; // B/C
			}
			if ( $right == 'autoconfirmed' ) {
				$right = 'editsemiprotected'; // B/C
			}
			if ( $tp and !$wgUser->isAllowed( $right ) ) {
				$errors[] = array( 'cantmove-titleprotected' );
			}
		}
		if ( empty( $errors ) ) {
			return true;
		}
		return $errors;
	}

	/**
	 * Check if the requested move target is a valid file move target
	 * @param Title $nt Target title
	 * @return array List of errors
	 */
	protected function validateFileMoveOperation( $nt ) {
		global $wgUser;

		$errors = array();

		// wfFindFile( $nt ) / wfLocalFile( $nt ) is not allowed until below

		$file = wfLocalFile( $this );
		if ( $file->exists() ) {
			if ( $nt->getText() != wfStripIllegalFilenameChars( $nt->getText() ) ) {
				$errors[] = array( 'imageinvalidfilename' );
			}
			if ( !File::checkExtensionCompatibility( $file, $nt->getDBkey() ) ) {
				$errors[] = array( 'imagetypemismatch' );
			}
		}

		if ( $nt->getNamespace() != NS_FILE ) {
			$errors[] = array( 'imagenocrossnamespace' );
			// From here we want to do checks on a file object, so if we can't
			// create one, we must return.
			return $errors;
		}

		// wfFindFile( $nt ) / wfLocalFile( $nt ) is allowed below here

		$destFile = wfLocalFile( $nt );
		if ( !$wgUser->isAllowed( 'reupload-shared' ) && !$destFile->exists() && wfFindFile( $nt ) ) {
			$errors[] = array( 'file-exists-sharedrepo' );
		}

		return $errors;
	}

	/**
	 * Move a title to a new location
	 *
	 * @todo Deprecate this in favor of MovePage
	 * @param Title $nt The new title
	 * @param bool $auth Indicates whether $wgUser's permissions
	 *  should be checked
	 * @param string $reason The reason for the move
	 * @param bool $createRedirect Whether to create a redirect from the old title to the new title.
	 *  Ignored if the user doesn't have the suppressredirect right.
	 * @return array|bool True on success, getUserPermissionsErrors()-like array on failure
	 */
	public function moveTo( &$nt, $auth = true, $reason = '', $createRedirect = true ) {
		global $wgUser;
		$err = $this->isValidMoveOperation( $nt, $auth, $reason );
		if ( is_array( $err ) ) {
			// Auto-block user's IP if the account was "hard" blocked
			$wgUser->spreadAnyEditBlock();
			return $err;
		}
		// Check suppressredirect permission
		if ( $auth && !$wgUser->isAllowed( 'suppressredirect' ) ) {
			$createRedirect = true;
		}

		wfRunHooks( 'TitleMove', array( $this, $nt, $wgUser ) );

		$mp = new MovePage( $this, $nt );
		$status = $mp->move( $wgUser, $reason, $createRedirect );
		if ( $status->isOK() ) {
			return true;
		} else {
			return $status->getErrorsArray();
		}
	}

	/**
	 * Move this page's subpages to be subpages of $nt
	 *
	 * @param Title $nt Move target
	 * @param bool $auth Whether $wgUser's permissions should be checked
	 * @param string $reason The reason for the move
	 * @param bool $createRedirect Whether to create redirects from the old subpages to
	 *     the new ones Ignored if the user doesn't have the 'suppressredirect' right
	 * @return array Array with old page titles as keys, and strings (new page titles) or
	 *     arrays (errors) as values, or an error array with numeric indices if no pages
	 *     were moved
	 */
	public function moveSubpages( $nt, $auth = true, $reason = '', $createRedirect = true ) {
		global $wgMaximumMovedPages;
		// Check permissions
		if ( !$this->userCan( 'move-subpages' ) ) {
			return array( 'cant-move-subpages' );
		}
		// Do the source and target namespaces support subpages?
		if ( !MWNamespace::hasSubpages( $this->getNamespace() ) ) {
			return array( 'namespace-nosubpages',
				MWNamespace::getCanonicalName( $this->getNamespace() ) );
		}
		if ( !MWNamespace::hasSubpages( $nt->getNamespace() ) ) {
			return array( 'namespace-nosubpages',
				MWNamespace::getCanonicalName( $nt->getNamespace() ) );
		}

		$subpages = $this->getSubpages( $wgMaximumMovedPages + 1 );
		$retval = array();
		$count = 0;
		foreach ( $subpages as $oldSubpage ) {
			$count++;
			if ( $count > $wgMaximumMovedPages ) {
				$retval[$oldSubpage->getPrefixedText()] =
						array( 'movepage-max-pages',
							$wgMaximumMovedPages );
				break;
			}

			// We don't know whether this function was called before
			// or after moving the root page, so check both
			// $this and $nt
			if ( $oldSubpage->getArticleID() == $this->getArticleID()
				|| $oldSubpage->getArticleID() == $nt->getArticleID()
			) {
				// When moving a page to a subpage of itself,
				// don't move it twice
				continue;
			}
			$newPageName = preg_replace(
					'#^' . preg_quote( $this->getDBkey(), '#' ) . '#',
					StringUtils::escapeRegexReplacement( $nt->getDBkey() ), # bug 21234
					$oldSubpage->getDBkey() );
			if ( $oldSubpage->isTalkPage() ) {
				$newNs = $nt->getTalkPage()->getNamespace();
			} else {
				$newNs = $nt->getSubjectPage()->getNamespace();
			}
			# Bug 14385: we need makeTitleSafe because the new page names may
			# be longer than 255 characters.
			$newSubpage = Title::makeTitleSafe( $newNs, $newPageName );

			$success = $oldSubpage->moveTo( $newSubpage, $auth, $reason, $createRedirect );
			if ( $success === true ) {
				$retval[$oldSubpage->getPrefixedText()] = $newSubpage->getPrefixedText();
			} else {
				$retval[$oldSubpage->getPrefixedText()] = $success;
			}
		}
		return $retval;
	}

	/**
	 * Checks if this page is just a one-rev redirect.
	 * Adds lock, so don't use just for light purposes.
	 *
	 * @return bool
	 */
	public function isSingleRevRedirect() {
		global $wgContentHandlerUseDB;

		$dbw = wfGetDB( DB_MASTER );

		# Is it a redirect?
		$fields = array( 'page_is_redirect', 'page_latest', 'page_id' );
		if ( $wgContentHandlerUseDB ) {
			$fields[] = 'page_content_model';
		}

		$row = $dbw->selectRow( 'page',
			$fields,
			$this->pageCond(),
			__METHOD__,
			array( 'FOR UPDATE' )
		);
		# Cache some fields we may want
		$this->mArticleID = $row ? intval( $row->page_id ) : 0;
		$this->mRedirect = $row ? (bool)$row->page_is_redirect : false;
		$this->mLatestID = $row ? intval( $row->page_latest ) : false;
		$this->mContentModel = $row && isset( $row->page_content_model )
			? strval( $row->page_content_model )
			: false;

		if ( !$this->mRedirect ) {
			return false;
		}
		# Does the article have a history?
		$row = $dbw->selectField( array( 'page', 'revision' ),
			'rev_id',
			array( 'page_namespace' => $this->getNamespace(),
				'page_title' => $this->getDBkey(),
				'page_id=rev_page',
				'page_latest != rev_id'
			),
			__METHOD__,
			array( 'FOR UPDATE' )
		);
		# Return true if there was no history
		return ( $row === false );
	}

	/**
	 * Checks if $this can be moved to a given Title
	 * - Selects for update, so don't call it unless you mean business
	 *
	 * @param Title $nt The new title to check
	 * @return bool
	 */
	public function isValidMoveTarget( $nt ) {
		# Is it an existing file?
		if ( $nt->getNamespace() == NS_FILE ) {
			$file = wfLocalFile( $nt );
			if ( $file->exists() ) {
				wfDebug( __METHOD__ . ": file exists\n" );
				return false;
			}
		}
		# Is it a redirect with no history?
		if ( !$nt->isSingleRevRedirect() ) {
			wfDebug( __METHOD__ . ": not a one-rev redirect\n" );
			return false;
		}
		# Get the article text
		$rev = Revision::newFromTitle( $nt, false, Revision::READ_LATEST );
		if ( !is_object( $rev ) ) {
			return false;
		}
		$content = $rev->getContent();
		# Does the redirect point to the source?
		# Or is it a broken self-redirect, usually caused by namespace collisions?
		$redirTitle = $content ? $content->getRedirectTarget() : null;

		if ( $redirTitle ) {
			if ( $redirTitle->getPrefixedDBkey() != $this->getPrefixedDBkey() &&
				$redirTitle->getPrefixedDBkey() != $nt->getPrefixedDBkey() ) {
				wfDebug( __METHOD__ . ": redirect points to other page\n" );
				return false;
			} else {
				return true;
			}
		} else {
			# Fail safe (not a redirect after all. strange.)
			wfDebug( __METHOD__ . ": failsafe: database sais " . $nt->getPrefixedDBkey() .
						" is a redirect, but it doesn't contain a valid redirect.\n" );
			return false;
		}
	}

	/**
	 * Get categories to which this Title belongs and return an array of
	 * categories' names.
	 *
	 * @return array Array of parents in the form:
	 *	  $parent => $currentarticle
	 */
	public function getParentCategories() {
		global $wgContLang;

		$data = array();

		$titleKey = $this->getArticleID();

		if ( $titleKey === 0 ) {
			return $data;
		}

		$dbr = wfGetDB( DB_SLAVE );

		$res = $dbr->select(
			'categorylinks',
			'cl_to',
			array( 'cl_from' => $titleKey ),
			__METHOD__
		);

		if ( $res->numRows() > 0 ) {
			foreach ( $res as $row ) {
				// $data[] = Title::newFromText($wgContLang->getNsText ( NS_CATEGORY ).':'.$row->cl_to);
				$data[$wgContLang->getNsText( NS_CATEGORY ) . ':' . $row->cl_to] = $this->getFullText();
			}
		}
		return $data;
	}

	/**
	 * Get a tree of parent categories
	 *
	 * @param array $children Array with the children in the keys, to check for circular refs
	 * @return array Tree of parent categories
	 */
	public function getParentCategoryTree( $children = array() ) {
		$stack = array();
		$parents = $this->getParentCategories();

		if ( $parents ) {
			foreach ( $parents as $parent => $current ) {
				if ( array_key_exists( $parent, $children ) ) {
					# Circular reference
					$stack[$parent] = array();
				} else {
					$nt = Title::newFromText( $parent );
					if ( $nt ) {
						$stack[$parent] = $nt->getParentCategoryTree( $children + array( $parent => 1 ) );
					}
				}
			}
		}

		return $stack;
	}

	/**
	 * Get an associative array for selecting this title from
	 * the "page" table
	 *
	 * @return array Array suitable for the $where parameter of DB::select()
	 */
	public function pageCond() {
		if ( $this->mArticleID > 0 ) {
			// PK avoids secondary lookups in InnoDB, shouldn't hurt other DBs
			return array( 'page_id' => $this->mArticleID );
		} else {
			return array( 'page_namespace' => $this->mNamespace, 'page_title' => $this->mDbkeyform );
		}
	}

	/**
	 * Get the revision ID of the previous revision
	 *
	 * @param int $revId Revision ID. Get the revision that was before this one.
	 * @param int $flags Title::GAID_FOR_UPDATE
	 * @return int|bool Old revision ID, or false if none exists
	 */
	public function getPreviousRevisionID( $revId, $flags = 0 ) {
		$db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
		$revId = $db->selectField( 'revision', 'rev_id',
			array(
				'rev_page' => $this->getArticleID( $flags ),
				'rev_id < ' . intval( $revId )
			),
			__METHOD__,
			array( 'ORDER BY' => 'rev_id DESC' )
		);

		if ( $revId === false ) {
			return false;
		} else {
			return intval( $revId );
		}
	}

	/**
	 * Get the revision ID of the next revision
	 *
	 * @param int $revId Revision ID. Get the revision that was after this one.
	 * @param int $flags Title::GAID_FOR_UPDATE
	 * @return int|bool Next revision ID, or false if none exists
	 */
	public function getNextRevisionID( $revId, $flags = 0 ) {
		$db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
		$revId = $db->selectField( 'revision', 'rev_id',
			array(
				'rev_page' => $this->getArticleID( $flags ),
				'rev_id > ' . intval( $revId )
			),
			__METHOD__,
			array( 'ORDER BY' => 'rev_id' )
		);

		if ( $revId === false ) {
			return false;
		} else {
			return intval( $revId );
		}
	}

	/**
	 * Get the first revision of the page
	 *
	 * @param int $flags Title::GAID_FOR_UPDATE
	 * @return Revision|null If page doesn't exist
	 */
	public function getFirstRevision( $flags = 0 ) {
		$pageId = $this->getArticleID( $flags );
		if ( $pageId ) {
			$db = ( $flags & self::GAID_FOR_UPDATE ) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
			$row = $db->selectRow( 'revision', Revision::selectFields(),
				array( 'rev_page' => $pageId ),
				__METHOD__,
				array( 'ORDER BY' => 'rev_timestamp ASC', 'LIMIT' => 1 )
			);
			if ( $row ) {
				return new Revision( $row );
			}
		}
		return null;
	}

	/**
	 * Get the oldest revision timestamp of this page
	 *
	 * @param int $flags Title::GAID_FOR_UPDATE
	 * @return string MW timestamp
	 */
	public function getEarliestRevTime( $flags = 0 ) {
		$rev = $this->getFirstRevision( $flags );
		return $rev ? $rev->getTimestamp() : null;
	}

	/**
	 * Check if this is a new page
	 *
	 * @return bool
	 */
	public function isNewPage() {
		$dbr = wfGetDB( DB_SLAVE );
		return (bool)$dbr->selectField( 'page', 'page_is_new', $this->pageCond(), __METHOD__ );
	}

	/**
	 * Check whether the number of revisions of this page surpasses $wgDeleteRevisionsLimit
	 *
	 * @return bool
	 */
	public function isBigDeletion() {
		global $wgDeleteRevisionsLimit;

		if ( !$wgDeleteRevisionsLimit ) {
			return false;
		}

		if ( $this->mIsBigDeletion === null ) {
			$dbr = wfGetDB( DB_SLAVE );

			$innerQuery = $dbr->selectSQLText(
				'revision',
				'1',
				array( 'rev_page' => $this->getArticleID() ),
				__METHOD__,
				array( 'LIMIT' => $wgDeleteRevisionsLimit + 1 )
			);

			$revCount = $dbr->query(
				'SELECT COUNT(*) FROM (' . $innerQuery . ') AS innerQuery',
				__METHOD__
			);
			$revCount = $revCount->fetchRow();
			$revCount = $revCount['COUNT(*)'];

			$this->mIsBigDeletion = $revCount > $wgDeleteRevisionsLimit;
		}

		return $this->mIsBigDeletion;
	}

	/**
	 * Get the approximate revision count of this page.
	 *
	 * @return int
	 */
	public function estimateRevisionCount() {
		if ( !$this->exists() ) {
			return 0;
		}

		if ( $this->mEstimateRevisions === null ) {
			$dbr = wfGetDB( DB_SLAVE );
			$this->mEstimateRevisions = $dbr->estimateRowCount( 'revision', '*',
				array( 'rev_page' => $this->getArticleID() ), __METHOD__ );
		}

		return $this->mEstimateRevisions;
	}

	/**
	 * Get the number of revisions between the given revision.
	 * Used for diffs and other things that really need it.
	 *
	 * @param int|Revision $old Old revision or rev ID (first before range)
	 * @param int|Revision $new New revision or rev ID (first after range)
	 * @param int|null $max Limit of Revisions to count, will be incremented to detect truncations
	 * @return int Number of revisions between these revisions.
	 */
	public function countRevisionsBetween( $old, $new, $max = null ) {
		if ( !( $old instanceof Revision ) ) {
			$old = Revision::newFromTitle( $this, (int)$old );
		}
		if ( !( $new instanceof Revision ) ) {
			$new = Revision::newFromTitle( $this, (int)$new );
		}
		if ( !$old || !$new ) {
			return 0; // nothing to compare
		}
		$dbr = wfGetDB( DB_SLAVE );
		$conds = array(
			'rev_page' => $this->getArticleID(),
			'rev_timestamp > ' . $dbr->addQuotes( $dbr->timestamp( $old->getTimestamp() ) ),
			'rev_timestamp < ' . $dbr->addQuotes( $dbr->timestamp( $new->getTimestamp() ) )
		);
		if ( $max !== null ) {
			$res = $dbr->select( 'revision', '1',
				$conds,
				__METHOD__,
				array( 'LIMIT' => $max + 1 ) // extra to detect truncation
			);
			return $res->numRows();
		} else {
			return (int)$dbr->selectField( 'revision', 'count(*)', $conds, __METHOD__ );
		}
	}

	/**
	 * Get the authors between the given revisions or revision IDs.
	 * Used for diffs and other things that really need it.
	 *
	 * @since 1.23
	 *
	 * @param int|Revision $old Old revision or rev ID (first before range by default)
	 * @param int|Revision $new New revision or rev ID (first after range by default)
	 * @param int $limit Maximum number of authors
	 * @param string|array $options (Optional): Single option, or an array of options:
	 *     'include_old' Include $old in the range; $new is excluded.
	 *     'include_new' Include $new in the range; $old is excluded.
	 *     'include_both' Include both $old and $new in the range.
	 *     Unknown option values are ignored.
	 * @return array|null Names of revision authors in the range; null if not both revisions exist
	 */
	public function getAuthorsBetween( $old, $new, $limit, $options = array() ) {
		if ( !( $old instanceof Revision ) ) {
			$old = Revision::newFromTitle( $this, (int)$old );
		}
		if ( !( $new instanceof Revision ) ) {
			$new = Revision::newFromTitle( $this, (int)$new );
		}
		// XXX: what if Revision objects are passed in, but they don't refer to this title?
		// Add $old->getPage() != $new->getPage() || $old->getPage() != $this->getArticleID()
		// in the sanity check below?
		if ( !$old || !$new ) {
			return null; // nothing to compare
		}
		$authors = array();
		$old_cmp = '>';
		$new_cmp = '<';
		$options = (array)$options;
		if ( in_array( 'include_old', $options ) ) {
			$old_cmp = '>=';
		}
		if ( in_array( 'include_new', $options ) ) {
			$new_cmp = '<=';
		}
		if ( in_array( 'include_both', $options ) ) {
			$old_cmp = '>=';
			$new_cmp = '<=';
		}
		// No DB query needed if $old and $new are the same or successive revisions:
		if ( $old->getId() === $new->getId() ) {
			return ( $old_cmp === '>' && $new_cmp === '<' ) ? array() : array( $old->getRawUserText() );
		} elseif ( $old->getId() === $new->getParentId() ) {
			if ( $old_cmp === '>=' && $new_cmp === '<=' ) {
				$authors[] = $old->getRawUserText();
				if ( $old->getRawUserText() != $new->getRawUserText() ) {
					$authors[] = $new->getRawUserText();
				}
			} elseif ( $old_cmp === '>=' ) {
				$authors[] = $old->getRawUserText();
			} elseif ( $new_cmp === '<=' ) {
				$authors[] = $new->getRawUserText();
			}
			return $authors;
		}
		$dbr = wfGetDB( DB_SLAVE );
		$res = $dbr->select( 'revision', 'DISTINCT rev_user_text',
			array(
				'rev_page' => $this->getArticleID(),
				"rev_timestamp $old_cmp " . $dbr->addQuotes( $dbr->timestamp( $old->getTimestamp() ) ),
				"rev_timestamp $new_cmp " . $dbr->addQuotes( $dbr->timestamp( $new->getTimestamp() ) )
			), __METHOD__,
			array( 'LIMIT' => $limit + 1 ) // add one so caller knows it was truncated
		);
		foreach ( $res as $row ) {
			$authors[] = $row->rev_user_text;
		}
		return $authors;
	}

	/**
	 * Get the number of authors between the given revisions or revision IDs.
	 * Used for diffs and other things that really need it.
	 *
	 * @param int|Revision $old Old revision or rev ID (first before range by default)
	 * @param int|Revision $new New revision or rev ID (first after range by default)
	 * @param int $limit Maximum number of authors
	 * @param string|array $options (Optional): Single option, or an array of options:
	 *     'include_old' Include $old in the range; $new is excluded.
	 *     'include_new' Include $new in the range; $old is excluded.
	 *     'include_both' Include both $old and $new in the range.
	 *     Unknown option values are ignored.
	 * @return int Number of revision authors in the range; zero if not both revisions exist
	 */
	public function countAuthorsBetween( $old, $new, $limit, $options = array() ) {
		$authors = $this->getAuthorsBetween( $old, $new, $limit, $options );
		return $authors ? count( $authors ) : 0;
	}

	/**
	 * Compare with another title.
	 *
	 * @param Title $title
	 * @return bool
	 */
	public function equals( Title $title ) {
		// Note: === is necessary for proper matching of number-like titles.
		return $this->getInterwiki() === $title->getInterwiki()
			&& $this->getNamespace() == $title->getNamespace()
			&& $this->getDBkey() === $title->getDBkey();
	}

	/**
	 * Check if this title is a subpage of another title
	 *
	 * @param Title $title
	 * @return bool
	 */
	public function isSubpageOf( Title $title ) {
		return $this->getInterwiki() === $title->getInterwiki()
			&& $this->getNamespace() == $title->getNamespace()
			&& strpos( $this->getDBkey(), $title->getDBkey() . '/' ) === 0;
	}

	/**
	 * Check if page exists.  For historical reasons, this function simply
	 * checks for the existence of the title in the page table, and will
	 * thus return false for interwiki links, special pages and the like.
	 * If you want to know if a title can be meaningfully viewed, you should
	 * probably call the isKnown() method instead.
	 *
	 * @return bool
	 */
	public function exists() {
		$exists = $this->getArticleID() != 0;
		wfRunHooks( 'TitleExists', array( $this, &$exists ) );
		return $exists;
	}

	/**
	 * Should links to this title be shown as potentially viewable (i.e. as
	 * "bluelinks"), even if there's no record by this title in the page
	 * table?
	 *
	 * This function is semi-deprecated for public use, as well as somewhat
	 * misleadingly named.  You probably just want to call isKnown(), which
	 * calls this function internally.
	 *
	 * (ISSUE: Most of these checks are cheap, but the file existence check
	 * can potentially be quite expensive.  Including it here fixes a lot of
	 * existing code, but we might want to add an optional parameter to skip
	 * it and any other expensive checks.)
	 *
	 * @return bool
	 */
	public function isAlwaysKnown() {
		$isKnown = null;

		/**
		 * Allows overriding default behavior for determining if a page exists.
		 * If $isKnown is kept as null, regular checks happen. If it's
		 * a boolean, this value is returned by the isKnown method.
		 *
		 * @since 1.20
		 *
		 * @param Title $title
		 * @param bool|null $isKnown
		 */
		wfRunHooks( 'TitleIsAlwaysKnown', array( $this, &$isKnown ) );

		if ( !is_null( $isKnown ) ) {
			return $isKnown;
		}

		if ( $this->isExternal() ) {
			return true;  // any interwiki link might be viewable, for all we know
		}

		switch ( $this->mNamespace ) {
			case NS_MEDIA:
			case NS_FILE:
				// file exists, possibly in a foreign repo
				return (bool)wfFindFile( $this );
			case NS_SPECIAL:
				// valid special page
				return SpecialPageFactory::exists( $this->getDBkey() );
			case NS_MAIN:
				// selflink, possibly with fragment
				return $this->mDbkeyform == '';
			case NS_MEDIAWIKI:
				// known system message
				return $this->hasSourceText() !== false;
			default:
				return false;
		}
	}

	/**
	 * Does this title refer to a page that can (or might) be meaningfully
	 * viewed?  In particular, this function may be used to determine if
	 * links to the title should be rendered as "bluelinks" (as opposed to
	 * "redlinks" to non-existent pages).
	 * Adding something else to this function will cause inconsistency
	 * since LinkHolderArray calls isAlwaysKnown() and does its own
	 * page existence check.
	 *
	 * @return bool
	 */
	public function isKnown() {
		return $this->isAlwaysKnown() || $this->exists();
	}

	/**
	 * Does this page have source text?
	 *
	 * @return bool
	 */
	public function hasSourceText() {
		if ( $this->exists() ) {
			return true;
		}

		if ( $this->mNamespace == NS_MEDIAWIKI ) {
			// If the page doesn't exist but is a known system message, default
			// message content will be displayed, same for language subpages-
			// Use always content language to avoid loading hundreds of languages
			// to get the link color.
			global $wgContLang;
			list( $name, ) = MessageCache::singleton()->figureMessage(
				$wgContLang->lcfirst( $this->getText() )
			);
			$message = wfMessage( $name )->inLanguage( $wgContLang )->useDatabase( false );
			return $message->exists();
		}

		return false;
	}

	/**
	 * Get the default message text or false if the message doesn't exist
	 *
	 * @return string|bool
	 */
	public function getDefaultMessageText() {
		global $wgContLang;

		if ( $this->getNamespace() != NS_MEDIAWIKI ) { // Just in case
			return false;
		}

		list( $name, $lang ) = MessageCache::singleton()->figureMessage(
			$wgContLang->lcfirst( $this->getText() )
		);
		$message = wfMessage( $name )->inLanguage( $lang )->useDatabase( false );

		if ( $message->exists() ) {
			return $message->plain();
		} else {
			return false;
		}
	}

	/**
	 * Updates page_touched for this page; called from LinksUpdate.php
	 *
	 * @return bool True if the update succeeded
	 */
	public function invalidateCache() {
		if ( wfReadOnly() ) {
			return false;
		}

		if ( $this->mArticleID === 0 ) {
			return true; // avoid gap locking if we know it's not there
		}

		$method = __METHOD__;
		$dbw = wfGetDB( DB_MASTER );
		$conds = $this->pageCond();
		$dbw->onTransactionIdle( function () use ( $dbw, $conds, $method ) {
			$dbw->update(
				'page',
				array( 'page_touched' => $dbw->timestamp() ),
				$conds,
				$method
			);
		} );

		return true;
	}

	/**
	 * Update page_touched timestamps and send squid purge messages for
	 * pages linking to this title. May be sent to the job queue depending
	 * on the number of links. Typically called on create and delete.
	 */
	public function touchLinks() {
		$u = new HTMLCacheUpdate( $this, 'pagelinks' );
		$u->doUpdate();

		if ( $this->getNamespace() == NS_CATEGORY ) {
			$u = new HTMLCacheUpdate( $this, 'categorylinks' );
			$u->doUpdate();
		}
	}

	/**
	 * Get the last touched timestamp
	 *
	 * @param DatabaseBase $db Optional db
	 * @return string Last-touched timestamp
	 */
	public function getTouched( $db = null ) {
		if ( $db === null ) {
			$db = wfGetDB( DB_SLAVE );
		}
		$touched = $db->selectField( 'page', 'page_touched', $this->pageCond(), __METHOD__ );
		return $touched;
	}

	/**
	 * Get the timestamp when this page was updated since the user last saw it.
	 *
	 * @param User $user
	 * @return string|null
	 */
	public function getNotificationTimestamp( $user = null ) {
		global $wgUser, $wgShowUpdatedMarker;
		// Assume current user if none given
		if ( !$user ) {
			$user = $wgUser;
		}
		// Check cache first
		$uid = $user->getId();
		// avoid isset here, as it'll return false for null entries
		if ( array_key_exists( $uid, $this->mNotificationTimestamp ) ) {
			return $this->mNotificationTimestamp[$uid];
		}
		if ( !$uid || !$wgShowUpdatedMarker || !$user->isAllowed( 'viewmywatchlist' ) ) {
			$this->mNotificationTimestamp[$uid] = false;
			return $this->mNotificationTimestamp[$uid];
		}
		// Don't cache too much!
		if ( count( $this->mNotificationTimestamp ) >= self::CACHE_MAX ) {
			$this->mNotificationTimestamp = array();
		}
		$dbr = wfGetDB( DB_SLAVE );
		$this->mNotificationTimestamp[$uid] = $dbr->selectField( 'watchlist',
			'wl_notificationtimestamp',
			array(
				'wl_user' => $user->getId(),
				'wl_namespace' => $this->getNamespace(),
				'wl_title' => $this->getDBkey(),
			),
			__METHOD__
		);
		return $this->mNotificationTimestamp[$uid];
	}

	/**
	 * Generate strings used for xml 'id' names in monobook tabs
	 *
	 * @param string $prepend Defaults to 'nstab-'
	 * @return string XML 'id' name
	 */
	public function getNamespaceKey( $prepend = 'nstab-' ) {
		global $wgContLang;
		// Gets the subject namespace if this title
		$namespace = MWNamespace::getSubject( $this->getNamespace() );
		// Checks if canonical namespace name exists for namespace
		if ( MWNamespace::exists( $this->getNamespace() ) ) {
			// Uses canonical namespace name
			$namespaceKey = MWNamespace::getCanonicalName( $namespace );
		} else {
			// Uses text of namespace
			$namespaceKey = $this->getSubjectNsText();
		}
		// Makes namespace key lowercase
		$namespaceKey = $wgContLang->lc( $namespaceKey );
		// Uses main
		if ( $namespaceKey == '' ) {
			$namespaceKey = 'main';
		}
		// Changes file to image for backwards compatibility
		if ( $namespaceKey == 'file' ) {
			$namespaceKey = 'image';
		}
		return $prepend . $namespaceKey;
	}

	/**
	 * Get all extant redirects to this Title
	 *
	 * @param int|null $ns Single namespace to consider; null to consider all namespaces
	 * @return Title[] Array of Title redirects to this title
	 */
	public function getRedirectsHere( $ns = null ) {
		$redirs = array();

		$dbr = wfGetDB( DB_SLAVE );
		$where = array(
			'rd_namespace' => $this->getNamespace(),
			'rd_title' => $this->getDBkey(),
			'rd_from = page_id'
		);
		if ( $this->isExternal() ) {
			$where['rd_interwiki'] = $this->getInterwiki();
		} else {
			$where[] = 'rd_interwiki = ' . $dbr->addQuotes( '' ) . ' OR rd_interwiki IS NULL';
		}
		if ( !is_null( $ns ) ) {
			$where['page_namespace'] = $ns;
		}

		$res = $dbr->select(
			array( 'redirect', 'page' ),
			array( 'page_namespace', 'page_title' ),
			$where,
			__METHOD__
		);

		foreach ( $res as $row ) {
			$redirs[] = self::newFromRow( $row );
		}
		return $redirs;
	}

	/**
	 * Check if this Title is a valid redirect target
	 *
	 * @return bool
	 */
	public function isValidRedirectTarget() {
		global $wgInvalidRedirectTargets;

		// invalid redirect targets are stored in a global array, but explicitly disallow Userlogout here
		if ( $this->isSpecial( 'Userlogout' ) ) {
			return false;
		}

		foreach ( $wgInvalidRedirectTargets as $target ) {
			if ( $this->isSpecial( $target ) ) {
				return false;
			}
		}

		return true;
	}

	/**
	 * Get a backlink cache object
	 *
	 * @return BacklinkCache
	 */
	public function getBacklinkCache() {
		return BacklinkCache::get( $this );
	}

	/**
	 * Whether the magic words __INDEX__ and __NOINDEX__ function for  this page.
	 *
	 * @return bool
	 */
	public function canUseNoindex() {
		global $wgContentNamespaces, $wgExemptFromUserRobotsControl;

		$bannedNamespaces = is_null( $wgExemptFromUserRobotsControl )
			? $wgContentNamespaces
			: $wgExemptFromUserRobotsControl;

		return !in_array( $this->mNamespace, $bannedNamespaces );

	}

	/**
	 * Returns the raw sort key to be used for categories, with the specified
	 * prefix.  This will be fed to Collation::getSortKey() to get a
	 * binary sortkey that can be used for actual sorting.
	 *
	 * @param string $prefix The prefix to be used, specified using
	 *   {{defaultsort:}} or like [[Category:Foo|prefix]].  Empty for no
	 *   prefix.
	 * @return string
	 */
	public function getCategorySortkey( $prefix = '' ) {
		$unprefixed = $this->getText();

		// Anything that uses this hook should only depend
		// on the Title object passed in, and should probably
		// tell the users to run updateCollations.php --force
		// in order to re-sort existing category relations.
		wfRunHooks( 'GetDefaultSortkey', array( $this, &$unprefixed ) );
		if ( $prefix !== '' ) {
			# Separate with a line feed, so the unprefixed part is only used as
			# a tiebreaker when two pages have the exact same prefix.
			# In UCA, tab is the only character that can sort above LF
			# so we strip both of them from the original prefix.
			$prefix = strtr( $prefix, "\n\t", '  ' );
			return "$prefix\n$unprefixed";
		}
		return $unprefixed;
	}

	/**
	 * Get the language in which the content of this page is written in
	 * wikitext. Defaults to $wgContLang, but in certain cases it can be
	 * e.g. $wgLang (such as special pages, which are in the user language).
	 *
	 * @since 1.18
	 * @return Language
	 */
	public function getPageLanguage() {
		global $wgLang, $wgLanguageCode;
		wfProfileIn( __METHOD__ );
		if ( $this->isSpecialPage() ) {
			// special pages are in the user language
			wfProfileOut( __METHOD__ );
			return $wgLang;
		}

		// Checking if DB language is set
		if ( $this->mDbPageLanguage ) {
			wfProfileOut( __METHOD__ );
			return wfGetLangObj( $this->mDbPageLanguage );
		}

		if ( !$this->mPageLanguage || $this->mPageLanguage[1] !== $wgLanguageCode ) {
			// Note that this may depend on user settings, so the cache should
			// be only per-request.
			// NOTE: ContentHandler::getPageLanguage() may need to load the
			// content to determine the page language!
			// Checking $wgLanguageCode hasn't changed for the benefit of unit
			// tests.
			$contentHandler = ContentHandler::getForTitle( $this );
			$langObj = wfGetLangObj( $contentHandler->getPageLanguage( $this ) );
			$this->mPageLanguage = array( $langObj->getCode(), $wgLanguageCode );
		} else {
			$langObj = wfGetLangObj( $this->mPageLanguage[0] );
		}

		wfProfileOut( __METHOD__ );
		return $langObj;
	}

	/**
	 * Get the language in which the content of this page is written when
	 * viewed by user. Defaults to $wgContLang, but in certain cases it can be
	 * e.g. $wgLang (such as special pages, which are in the user language).
	 *
	 * @since 1.20
	 * @return Language
	 */
	public function getPageViewLanguage() {
		global $wgLang;

		if ( $this->isSpecialPage() ) {
			// If the user chooses a variant, the content is actually
			// in a language whose code is the variant code.
			$variant = $wgLang->getPreferredVariant();
			if ( $wgLang->getCode() !== $variant ) {
				return Language::factory( $variant );
			}

			return $wgLang;
		}

		// @note Can't be cached persistently, depends on user settings.
		// @note ContentHandler::getPageViewLanguage() may need to load the
		//   content to determine the page language!
		$contentHandler = ContentHandler::getForTitle( $this );
		$pageLang = $contentHandler->getPageViewLanguage( $this );
		return $pageLang;
	}

	/**
	 * Get a list of rendered edit notices for this page.
	 *
	 * Array is keyed by the original message key, and values are rendered using parseAsBlock, so
	 * they will already be wrapped in paragraphs.
	 *
	 * @since 1.21
	 * @param int $oldid Revision ID that's being edited
	 * @return array
	 */
	public function getEditNotices( $oldid = 0 ) {
		$notices = array();

		# Optional notices on a per-namespace and per-page basis
		$editnotice_ns = 'editnotice-' . $this->getNamespace();
		$editnotice_ns_message = wfMessage( $editnotice_ns );
		if ( $editnotice_ns_message->exists() ) {
			$notices[$editnotice_ns] = $editnotice_ns_message->parseAsBlock();
		}
		if ( MWNamespace::hasSubpages( $this->getNamespace() ) ) {
			$parts = explode( '/', $this->getDBkey() );
			$editnotice_base = $editnotice_ns;
			while ( count( $parts ) > 0 ) {
				$editnotice_base .= '-' . array_shift( $parts );
				$editnotice_base_msg = wfMessage( $editnotice_base );
				if ( $editnotice_base_msg->exists() ) {
					$notices[$editnotice_base] = $editnotice_base_msg->parseAsBlock();
				}
			}
		} else {
			# Even if there are no subpages in namespace, we still don't want / in MW ns.
			$editnoticeText = $editnotice_ns . '-' . str_replace( '/', '-', $this->getDBkey() );
			$editnoticeMsg = wfMessage( $editnoticeText );
			if ( $editnoticeMsg->exists() ) {
				$notices[$editnoticeText] = $editnoticeMsg->parseAsBlock();
			}
		}

		wfRunHooks( 'TitleGetEditNotices', array( $this, $oldid, &$notices ) );
		return $notices;
	}
}