summaryrefslogtreecommitdiffstats
path: root/Bugzilla/Search.pm
blob: 656d163ea82b4aa101fcec8389e291169b5dd80b (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
# -*- Mode: perl; indent-tabs-mode: nil -*-
#
# The contents of this file are subject to the Mozilla Public
# License Version 1.1 (the "License"); you may not use this file
# except in compliance with the License. You may obtain a copy of
# the License at http://www.mozilla.org/MPL/
#
# Software distributed under the License is distributed on an "AS
# IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
# implied. See the License for the specific language governing
# rights and limitations under the License.
#
# The Original Code is the Bugzilla Bug Tracking System.
#
# The Initial Developer of the Original Code is Netscape Communications
# Corporation. Portions created by Netscape are
# Copyright (C) 1998 Netscape Communications Corporation. All
# Rights Reserved.
#
# Contributor(s): Gervase Markham <gerv@gerv.net>
#                 Terry Weissman <terry@mozilla.org>
#                 Dan Mosedale <dmose@mozilla.org>
#                 Stephan Niemz <st.n@gmx.net>
#                 Andreas Franke <afranke@mathweb.org>
#                 Myk Melez <myk@mozilla.org>
#                 Michael Schindler <michael@compressconsult.com>
#                 Max Kanat-Alexander <mkanat@bugzilla.org>
#                 Joel Peshkin <bugreport@peshkin.net>
#                 Lance Larsh <lance.larsh@oracle.com>
#                 Jesse Clark <jjclark1982@gmail.com>
#                 Rémi Zara <remi_zara@mac.com>
#                 Reed Loden <reed@reedloden.com>

use strict;

package Bugzilla::Search;
use base qw(Exporter);
@Bugzilla::Search::EXPORT = qw(
    IsValidQueryType
    split_order_term
    translate_old_column
);

use Bugzilla::Error;
use Bugzilla::Util;
use Bugzilla::Constants;
use Bugzilla::Group;
use Bugzilla::User;
use Bugzilla::Field;
use Bugzilla::Search::Clause;
use Bugzilla::Search::Condition qw(condition);
use Bugzilla::Status;
use Bugzilla::Keyword;

use Data::Dumper;
use Date::Format;
use Date::Parse;
use Scalar::Util qw(blessed);
use List::MoreUtils qw(all part uniq);
use POSIX qw(INT_MAX);
use Storable qw(dclone);

# Description Of Boolean Charts
# -----------------------------
#
# A boolean chart is a way of representing the terms in a logical
# expression.  Bugzilla builds SQL queries depending on how you enter
# terms into the boolean chart. Boolean charts are represented in
# urls as three-tuples of (chart id, row, column). The query form
# (query.cgi) may contain an arbitrary number of boolean charts where
# each chart represents a clause in a SQL query.
#
# The query form starts out with one boolean chart containing one
# row and one column.  Extra rows can be created by pressing the
# AND button at the bottom of the chart.  Extra columns are created
# by pressing the OR button at the right end of the chart. Extra
# charts are created by pressing "Add another boolean chart".
#
# Each chart consists of an arbitrary number of rows and columns.
# The terms within a row are ORed together. The expressions represented
# by each row are ANDed together. The expressions represented by each
# chart are ANDed together.
#
#        ----------------------
#        | col2 | col2 | col3 |
# --------------|------|------|
# | row1 |  a1  |  a2  |      |
# |------|------|------|------|  => ((a1 OR a2) AND (b1 OR b2 OR b3) AND (c1))
# | row2 |  b1  |  b2  |  b3  |
# |------|------|------|------|
# | row3 |  c1  |      |      |
# -----------------------------
#
#        --------
#        | col2 |
# --------------|
# | row1 |  d1  | => (d1)
# ---------------
#
# Together, these two charts represent a SQL expression like this
# SELECT blah FROM blah WHERE ( (a1 OR a2)AND(b1 OR b2 OR b3)AND(c1)) AND (d1)
#
# The terms within a single row of a boolean chart are all constraints
# on a single piece of data.  If you're looking for a bug that has two
# different people cc'd on it, then you need to use two boolean charts.
# This will find bugs with one CC matching 'foo@blah.org' and and another
# CC matching 'bar@blah.org'.
#
# --------------------------------------------------------------
# CC    | equal to
# foo@blah.org
# --------------------------------------------------------------
# CC    | equal to
# bar@blah.org
#
# If you try to do this query by pressing the AND button in the
# original boolean chart then what you'll get is an expression that
# looks for a single CC where the login name is both "foo@blah.org",
# and "bar@blah.org". This is impossible.
#
# --------------------------------------------------------------
# CC    | equal to
# foo@blah.org
# AND
# CC    | equal to
# bar@blah.org
# --------------------------------------------------------------

#############
# Constants #
#############

# When doing searches, NULL datetimes are treated as this date.
use constant EMPTY_DATETIME => '1970-01-01 00:00:00';

# This is the regex for real numbers from Regexp::Common, modified to be
# more readable.
use constant NUMBER_REGEX => qr/
    ^[+-]?      # A sign, optionally.

    (?=\d|\.)   # Then either a digit or "."
    \d*         # Followed by many other digits
    (?:
        \.      # Followed possibly by some decimal places
        (?:\d*)
    )?
 
    (?:         # Followed possibly by an exponent.
        [Ee]
        [+-]?
        \d+
    )?
    $
/x;

# If you specify a search type in the boolean charts, this describes
# which operator maps to which internal function here.
use constant OPERATORS => {
    equals         => \&_simple_operator,
    notequals      => \&_simple_operator,
    casesubstring  => \&_casesubstring,
    substring      => \&_substring,
    substr         => \&_substring,
    notsubstring   => \&_notsubstring,
    regexp         => \&_regexp,
    notregexp      => \&_notregexp,
    lessthan       => \&_simple_operator,
    lessthaneq     => \&_simple_operator,
    matches        => sub { ThrowUserError("search_content_without_matches"); },
    notmatches     => sub { ThrowUserError("search_content_without_matches"); },
    greaterthan    => \&_simple_operator,
    greaterthaneq  => \&_simple_operator,
    anyexact       => \&_anyexact,
    anywordssubstr => \&_anywordsubstr,
    allwordssubstr => \&_allwordssubstr,
    nowordssubstr  => \&_nowordssubstr,
    anywords       => \&_anywords,
    allwords       => \&_allwords,
    nowords        => \&_nowords,
    changedbefore  => \&_changedbefore_changedafter,
    changedafter   => \&_changedbefore_changedafter,
    changedfrom    => \&_changedfrom_changedto,
    changedto      => \&_changedfrom_changedto,
    changedby      => \&_changedby,
};

# Some operators are really just standard SQL operators, and are
# all implemented by the _simple_operator function, which uses this
# constant.
use constant SIMPLE_OPERATORS => {
    equals        => '=',
    notequals     => '!=',
    greaterthan   => '>',
    greaterthaneq => '>=',
    lessthan      => '<',
    lessthaneq    => "<=",
};

# Most operators just reverse by removing or adding "not" from/to them.
# However, some operators reverse in a different way, so those are listed
# here.
use constant OPERATOR_REVERSE => {
    nowords        => 'anywords',
    nowordssubstr  => 'anywordssubstr',
    anywords       => 'nowords',
    anywordssubstr => 'nowordssubstr',
    lessthan       => 'greaterthaneq',
    lessthaneq     => 'greaterthan',
    greaterthan    => 'lessthaneq',
    greaterthaneq  => 'lessthan',
    # The following don't currently have reversals:
    # casesubstring, anyexact, allwords, allwordssubstr
};

# For these operators, even if a field is numeric (is_numeric returns true),
# we won't treat the input like a number.
use constant NON_NUMERIC_OPERATORS => qw(
    changedafter
    changedbefore
    changedfrom
    changedto
    regexp
    notregexp
);

use constant MULTI_SELECT_OVERRIDE => {
    notequals      => \&_multiselect_negative,
    notregexp      => \&_multiselect_negative,
    notsubstring   => \&_multiselect_negative,
    nowords        => \&_multiselect_negative,
    nowordssubstr  => \&_multiselect_negative,
    
    allwords       => \&_multiselect_multiple,
    allwordssubstr => \&_multiselect_multiple,
    anyexact       => \&_multiselect_multiple,
    anywords       => \&_multiselect_multiple,
    anywordssubstr => \&_multiselect_multiple,
    
    _non_changed    => \&_multiselect_nonchanged,
};

use constant OPERATOR_FIELD_OVERRIDE => {
    # User fields
    'attachments.submitter' => {
        _non_changed => \&_user_nonchanged,
    },
    assigned_to => {
        _non_changed => \&_user_nonchanged,
    },
    cc => {
        _non_changed => \&_user_nonchanged,
    },
    commenter => {
        _non_changed => \&_user_nonchanged,
    },
    reporter => {
        _non_changed => \&_user_nonchanged,
    },
    'requestees.login_name' => {
        _non_changed => \&_user_nonchanged,
    },
    'setters.login_name' => {
        _non_changed => \&_user_nonchanged,    
    },
    qa_contact => {
        _non_changed => \&_user_nonchanged,
    },
    
    # General Bug Fields
    alias        => { _non_changed => \&_nullable },
    'attach_data.thedata' => MULTI_SELECT_OVERRIDE,
    # We check all attachment fields against this.
    attachments  => MULTI_SELECT_OVERRIDE,
    blocked      => MULTI_SELECT_OVERRIDE,
    bug_file_loc => { _non_changed => \&_nullable },
    bug_group    => MULTI_SELECT_OVERRIDE,
    classification => {
        _non_changed => \&_classification_nonchanged,
    },
    component => {
        _non_changed => \&_component_nonchanged,
    },
    content => {
        matches    => \&_content_matches,
        notmatches => \&_content_matches,
        _default   => sub { ThrowUserError("search_content_without_matches"); },
    },
    days_elapsed => {
        _default => \&_days_elapsed,
    },
    dependson        => MULTI_SELECT_OVERRIDE,
    keywords         => MULTI_SELECT_OVERRIDE,
    'flagtypes.name' => MULTI_SELECT_OVERRIDE,
    longdesc => {
        %{ MULTI_SELECT_OVERRIDE() },
        changedby     => \&_long_desc_changedby,
        changedbefore => \&_long_desc_changedbefore_after,
        changedafter  => \&_long_desc_changedbefore_after,
    },
    'longdescs.count' => {
        changedby     => \&_long_desc_changedby,
        changedbefore => \&_long_desc_changedbefore_after,
        changedafter  => \&_long_desc_changedbefore_after,
        changedfrom   => \&_invalid_combination,
        changedto     => \&_invalid_combination,
        _default      => \&_long_descs_count,
    },
    'longdescs.isprivate' => MULTI_SELECT_OVERRIDE,
    owner_idle_time => {
        greaterthan   => \&_owner_idle_time_greater_less,
        greaterthaneq => \&_owner_idle_time_greater_less,
        lessthan      => \&_owner_idle_time_greater_less,
        lessthaneq    => \&_owner_idle_time_greater_less,
        _default      => \&_invalid_combination,
    },
    product => {
        _non_changed => \&_product_nonchanged,
    },
    tag => MULTI_SELECT_OVERRIDE,
    
    # Timetracking Fields
    deadline => { _non_changed => \&_deadline },
    percentage_complete => {
        _non_changed => \&_percentage_complete,
    },
    work_time => {
        changedby     => \&_work_time_changedby,
        changedbefore => \&_work_time_changedbefore_after,
        changedafter  => \&_work_time_changedbefore_after,
        _default      => \&_work_time,
    },
    
    # Custom Fields
    FIELD_TYPE_FREETEXT, { _non_changed => \&_nullable },
    FIELD_TYPE_BUG_ID,   { _non_changed => \&_nullable_int },
    FIELD_TYPE_DATETIME, { _non_changed => \&_nullable_datetime },
    FIELD_TYPE_TEXTAREA, { _non_changed => \&_nullable },
    FIELD_TYPE_MULTI_SELECT, MULTI_SELECT_OVERRIDE,
    FIELD_TYPE_BUG_URLS,     MULTI_SELECT_OVERRIDE,    
};

# These are fields where special action is taken depending on the
# *value* passed in to the chart, sometimes.
use constant SPECIAL_PARSING => {
    # Pronoun Fields (Ones that can accept %user%, etc.)
    assigned_to => \&_contact_pronoun,
    cc          => \&_cc_pronoun,
    commenter   => \&_commenter_pronoun,
    qa_contact  => \&_contact_pronoun,
    reporter    => \&_contact_pronoun,
    
    # Date Fields that accept the 1d, 1w, 1m, 1y, etc. format.
    creation_ts => \&_timestamp_translate,
    deadline    => \&_timestamp_translate,
    delta_ts    => \&_timestamp_translate,
};

# Information about fields that represent "users", used by _user_nonchanged.
# There are other user fields than the ones listed here, but those use
# defaults in _user_nonchanged.
use constant USER_FIELDS => {
    'attachments.submitter' => {
        field    => 'submitter_id',
        join     => { table => 'attachments' },
        isprivate => 1,
    },
    cc => {
        field => 'who',
        join  => { table => 'cc' },
    },
    commenter => {
        field => 'who',
        join  => { table => 'longdescs', join => 'INNER' },
        isprivate => 1,
    },
    qa_contact => {
        nullable => 1,
    },
    'requestees.login_name' => {
        nullable => 1,
        field    => 'requestee_id',
        join     => { table => 'flags' },
    },
    'setters.login_name' => {
        field    => 'setter_id',
        join     => { table => 'flags' },
    },
};

# Backwards compatibility for times that we changed the names of fields
# or URL parameters.
use constant FIELD_MAP => {
    'attachments.thedata' => 'attach_data.thedata',
    bugidtype => 'bug_id_type',
    changedin => 'days_elapsed',
    long_desc => 'longdesc',
};

# Some fields are not sorted on themselves, but on other fields.
# We need to have a list of these fields and what they map to.
use constant SPECIAL_ORDER => {
    'target_milestone' => {
        order => ['map_target_milestone.sortkey','map_target_milestone.value'],
        join  => {
            table => 'milestones',
            from  => 'target_milestone',
            to    => 'value',
            extra => ['bugs.product_id = map_target_milestone.product_id'],
            join  => 'INNER',
        }
    },
};

# Certain columns require other columns to come before them
# in _select_columns, and should be put there if they're not there.
use constant COLUMN_DEPENDS => {
    classification      => ['product'],
    percentage_complete => ['actual_time', 'remaining_time'],
};

# This describes tables that must be joined when you want to display
# certain columns in the buglist. For the most part, Search.pm uses
# DB::Schema to figure out what needs to be joined, but for some
# fields it needs a little help.
use constant COLUMN_JOINS => {
    actual_time => {
        table => '(SELECT bug_id, SUM(work_time) AS total'
                 . ' FROM longdescs GROUP BY bug_id)',
        join  => 'INNER',
    },
    assigned_to => {
        from  => 'assigned_to',
        to    => 'userid',
        table => 'profiles',
        join  => 'INNER',
    },
    reporter => {
        from  => 'reporter',
        to    => 'userid',
        table => 'profiles',
        join  => 'INNER',
    },
    qa_contact => {
        from  => 'qa_contact',
        to    => 'userid',
        table => 'profiles',
    },
    component => {
        from  => 'component_id',
        to    => 'id',
        table => 'components',
        join  => 'INNER',
    },
    product => {
        from  => 'product_id',
        to    => 'id',
        table => 'products',
        join  => 'INNER',
    },
    classification => {
        table => 'classifications',
        from  => 'map_product.classification_id',
        to    => 'id',
        join  => 'INNER',
    },
    'flagtypes.name' => {
        as    => 'map_flags',
        table => 'flags',
        extra => ['map_flags.attach_id IS NULL'],
        then_to => {
            as    => 'map_flagtypes',
            table => 'flagtypes',
            from  => 'map_flags.type_id',
            to    => 'id',
        },
    },
    keywords => {
        table => 'keywords',
        then_to => {
            as    => 'map_keyworddefs',
            table => 'keyworddefs',
            from  => 'map_keywords.keywordid',
            to    => 'id',
        },
    },
    'longdescs.count' => {
        table => 'longdescs',
        join  => 'INNER',
    },
};

# This constant defines the columns that can be selected in a query 
# and/or displayed in a bug list.  Column records include the following
# fields:
#
# 1. id: a unique identifier by which the column is referred in code;
#
# 2. name: The name of the column in the database (may also be an expression
#          that returns the value of the column);
#
# 3. title: The title of the column as displayed to users.
# 
# Note: There are a few hacks in the code that deviate from these definitions.
#       In particular, the redundant short_desc column is removed when the
#       client requests "all" columns.
#
# This is really a constant--that is, once it's been called once, the value
# will always be the same unless somebody adds a new custom field. But
# we have to do a lot of work inside the subroutine to get the data,
# and we don't want it to happen at compile time, so we have it as a
# subroutine.
sub COLUMNS {
    my $invocant = shift;
    my $user = blessed($invocant) ? $invocant->_user : Bugzilla->user;
    my $dbh = Bugzilla->dbh;
    my $cache = Bugzilla->request_cache;

    if (defined $cache->{search_columns}->{$user->id}) {
        return $cache->{search_columns}->{$user->id};
    }

    # These are columns that don't exist in fielddefs, but are valid buglist
    # columns. (Also see near the bottom of this function for the definition
    # of short_short_desc.)
    my %columns = (
        relevance            => { title => 'Relevance'  },
        assigned_to_realname => { title => 'Assignee'   },
        reporter_realname    => { title => 'Reporter'   },
        qa_contact_realname  => { title => 'QA Contact' },
    );

    # Next we define columns that have special SQL instead of just something
    # like "bugs.bug_id".
    my $total_time = "(map_actual_time.total + bugs.remaining_time)";
    my %special_sql = (
        deadline    => $dbh->sql_date_format('bugs.deadline', '%Y-%m-%d'),
        actual_time => 'map_actual_time.total',

        # "FLOOR" is in there to turn this into an integer, making searches
        # totally predictable. Otherwise you get floating-point numbers that
        # are rather hard to search reliably if you're asking for exact
        # numbers.
        percentage_complete =>
            "(CASE WHEN $total_time = 0"
               . " THEN 0"
               . " ELSE FLOOR(100 * (map_actual_time.total / $total_time))"
                . " END)",

        'flagtypes.name' => $dbh->sql_group_concat('DISTINCT ' 
            . $dbh->sql_string_concat('map_flagtypes.name', 'map_flags.status')),

        'keywords' => $dbh->sql_group_concat('DISTINCT map_keyworddefs.name'),
        
        'longdescs.count' => 'COUNT(DISTINCT map_longdescs_count.comment_id)',
    );

    # Backward-compatibility for old field names. Goes new_name => old_name.
    # These are here and not in translate_old_column because the rest of the
    # code actually still uses the old names, while the fielddefs table uses
    # the new names (which is not the case for the fields handled by 
    # translate_old_column).
    my %old_names = (
        creation_ts => 'opendate',
        delta_ts    => 'changeddate',
        work_time   => 'actual_time',
    );

    # Fields that are email addresses
    my @email_fields = qw(assigned_to reporter qa_contact);
    # Other fields that are stored in the bugs table as an id, but
    # should be displayed using their name.
    my @id_fields = qw(product component classification);

    foreach my $col (@email_fields) {
        my $sql = "map_${col}.login_name";
        if (!$user->id) {
             $sql = $dbh->sql_string_until($sql, $dbh->quote('@'));
        }
        $special_sql{$col} = $sql;
        $columns{"${col}_realname"}->{name} = "map_${col}.realname";
    }

    foreach my $col (@id_fields) {
        $special_sql{$col} = "map_${col}.name";
    }

    # Do the actual column-getting from fielddefs, now.
    my @fields = @{ Bugzilla->fields({ obsolete => 0, buglist => 1 }) };
    foreach my $field (@fields) {
        my $id = $field->name;
        $id = $old_names{$id} if exists $old_names{$id};
        my $sql;
        if (exists $special_sql{$id}) {
            $sql = $special_sql{$id};
        }
        elsif ($field->type == FIELD_TYPE_MULTI_SELECT) {
            $sql = $dbh->sql_group_concat(
                'DISTINCT map_' . $field->name . '.value');
        }
        else {
            $sql = 'bugs.' . $field->name;
        }
        $columns{$id} = { name => $sql, title => $field->description };
    }

    # The short_short_desc column is identical to short_desc
    $columns{'short_short_desc'} = $columns{'short_desc'};

    Bugzilla::Hook::process('buglist_columns', { columns => \%columns });

    $cache->{search_columns}->{$user->id} = \%columns;
    return $cache->{search_columns}->{$user->id};
}

sub REPORT_COLUMNS {
    my $invocant = shift;
    my $user = blessed($invocant) ? $invocant->_user : Bugzilla->user;

    my $columns = dclone(blessed($invocant) ? $invocant->COLUMNS : COLUMNS);
    # There's no reason to support reporting on unique fields.
    # Also, some other fields don't make very good reporting axises,
    # or simply don't work with the current reporting system.
    my @no_report_columns = 
        qw(bug_id alias short_short_desc opendate changeddate
           flagtypes.name keywords relevance);

    # Multi-select fields are not currently supported.
    my @multi_selects = @{Bugzilla->fields(
        { obsolete => 0, type => FIELD_TYPE_MULTI_SELECT })};
    push(@no_report_columns, map { $_->name } @multi_selects);

    # If you're not a time-tracker, you can't use time-tracking
    # columns.
    if (!$user->is_timetracker) {
        push(@no_report_columns, TIMETRACKING_FIELDS);
    }

    foreach my $name (@no_report_columns) {
        delete $columns->{$name};
    }
    return $columns;
}

# These are fields that never go into the GROUP BY on any DB. bug_id
# is here because it *always* goes into the GROUP BY as the first item,
# so it should be skipped when determining extra GROUP BY columns.
use constant GROUP_BY_SKIP => qw(
    bug_id
    flagtypes.name
    keywords
    longdescs.count
    percentage_complete
);

###############
# Constructor #
###############

# Note that the params argument may be modified by Bugzilla::Search
sub new {
    my $invocant = shift;
    my $class = ref($invocant) || $invocant;
  
    my $self = { @_ };
    bless($self, $class);
    $self->{'user'} ||= Bugzilla->user;
    
    # There are certain behaviors of the CGI "Vars" hash that we don't want.
    # In particular, if you put a single-value arrayref into it, later you
    # get back out a string, which breaks anyexact charts (because they
    # need arrays even for individual items, or we will re-trigger bug 67036).
    #
    # We can't just untie the hash--that would give us a hash with no values.
    # We have to manually copy the hash into a new one, and we have to always
    # do it, because there's no way to know if we were passed a tied hash
    # or not.
    my $params_in = $self->_params;
    my %params = map { $_ => $params_in->{$_} } keys %$params_in;
    $self->{params} = \%params;

    return $self;
}


####################
# Public Accessors #
####################

sub sql {
    my ($self) = @_;
    return $self->{sql} if $self->{sql};
    my $dbh = Bugzilla->dbh;
    
    my ($joins, $clause) = $self->_charts_to_conditions();
    my $select = join(', ', $self->_sql_select);
    my $from = $self->_sql_from($joins);
    my $where = $self->_sql_where($clause);
    my $group_by = $dbh->sql_group_by($self->_sql_group_by);
    my $order_by = $self->_sql_order_by
                   ? "\nORDER BY " . join(', ', $self->_sql_order_by) : '';
    my $limit = $self->_sql_limit;
    $limit = "\n$limit" if $limit;
    
    my $query = <<END;
SELECT $select
  FROM $from
 WHERE $where
$group_by$order_by$limit
END
    $self->{sql} = $query;
    return $self->{sql};
}

sub search_description {
    my ($self, $params) = @_;
    my $desc = $self->{'search_description'} ||= [];
    if ($params) {
        push(@$desc, $params);
    }
    # Make sure that the description has actually been generated if
    # people are asking for the whole thing.
    else {
        $self->sql;
    }
    return $self->{'search_description'};
}

sub boolean_charts_to_custom_search {
    my ($self, $cgi_buffer) = @_;
    my @as_params = $self->_boolean_charts->as_params;

    # We need to start our new ids after the last custom search "f" id.
    # We can just pick the last id in the array because they are sorted
    # numerically.
    my $last_id = ($self->_field_ids)[-1];
    my $count = defined($last_id) ? $last_id + 1 : 0;
    foreach my $param_set (@as_params) {
        foreach my $name (keys %$param_set) {
            my $value = $param_set->{$name};
            next if !defined $value;
            $cgi_buffer->param($name . $count, $value);
        }
        $count++;
    }
}

######################
# Internal Accessors #
######################

# Fields that are legal for boolean charts of any kind.
sub _chart_fields {
    my ($self) = @_;

    if (!$self->{chart_fields}) {
        my $chart_fields = Bugzilla->fields({ by_name => 1 });

        if (!$self->_user->is_timetracker) {
            foreach my $tt_field (TIMETRACKING_FIELDS) {
                delete $chart_fields->{$tt_field};
            }
        }
        $self->{chart_fields} = $chart_fields;
    }
    return $self->{chart_fields};
}

# There are various places in Search.pm that we need to know the list of
# valid multi-select fields--or really, fields that are stored like
# multi-selects, which includes BUG_URLS fields.
sub _multi_select_fields {
    my ($self) = @_;
    $self->{multi_select_fields} ||= Bugzilla->fields({
        by_name => 1,
        type    => [FIELD_TYPE_MULTI_SELECT, FIELD_TYPE_BUG_URLS]});
    return $self->{multi_select_fields};
}

# $self->{params} contains values that could be undef, could be a string,
# or could be an arrayref. Sometimes we want that value as an array,
# always.
sub _param_array {
    my ($self, $name) = @_;
    my $value = $self->_params->{$name};
    if (!defined $value) {
        return ();
    }
    if (ref($value) eq 'ARRAY') {
        return @$value;
    }
    return ($value);
}

sub _params { $_[0]->{params} }
sub _user { return $_[0]->{user} }
sub _sharer_id { $_[0]->{sharer} }

##############################
# Internal Accessors: SELECT #
##############################

# These are the fields the user has chosen to display on the buglist,
# exactly as they were passed to new().
sub _input_columns { @{ $_[0]->{'fields'} || [] } }

# These are columns that are also going to be in the SELECT for one reason
# or another, but weren't actually requested by the caller.
sub _extra_columns {
    my ($self) = @_;
    # Everything that's going to be in the ORDER BY must also be
    # in the SELECT.
    push(@{ $self->{extra_columns} }, $self->_input_order_columns);
    return @{ $self->{extra_columns} };
}

# For search functions to modify extra_columns. It doesn't matter if
# people push the same column onto this array multiple times, because
# _select_columns will call "uniq" on its final result.
sub _add_extra_column {
    my ($self, $column) = @_;
    push(@{ $self->{extra_columns} }, $column);
}

# These are the columns that we're going to be actually SELECTing.
sub _display_columns {
    my ($self) = @_;
    return @{ $self->{display_columns} } if $self->{display_columns};

    # Do not alter the list from _input_columns at all, even if there are
    # duplicated columns. Those are passed by the caller, and the caller
    # expects to get them back in the exact same order.
    my @columns = $self->_input_columns;

    # Only add columns which are not already listed.
    my %list = map { $_ => 1 } @columns;
    foreach my $column ($self->_extra_columns) {
        push(@columns, $column) unless $list{$column}++;
    }
    $self->{display_columns} = \@columns;
    return @{ $self->{display_columns} };
}

# These are the columns that are involved in the query.
sub _select_columns {
    my ($self) = @_;
    return @{ $self->{select_columns} } if $self->{select_columns};

    my @select_columns;
    foreach my $column ($self->_display_columns) {
        if (my $add_first = COLUMN_DEPENDS->{$column}) {
            push(@select_columns, @$add_first);
        }
        push(@select_columns, $column);
    }
    # Remove duplicated columns.
    $self->{select_columns} = [uniq @select_columns];
    return @{ $self->{select_columns} };
}

# This takes _display_columns and translates it into the actual SQL that
# will go into the SELECT clause.
sub _sql_select {
    my ($self) = @_;
    my @sql_fields;
    foreach my $column ($self->_display_columns) {
        my $alias = $column;
        # Aliases cannot contain dots in them. We convert them to underscores.
        $alias =~ s/\./_/g;
        my $sql = $self->COLUMNS->{$column}->{name} . " AS $alias";
        push(@sql_fields, $sql);
    }
    return @sql_fields;
}

################################
# Internal Accessors: ORDER BY #
################################

# The "order" that was requested by the consumer, exactly as it was
# requested.
sub _input_order { @{ $_[0]->{'order'} || [] } }
# The input order with just the column names, and no ASC or DESC.
sub _input_order_columns {
    my ($self) = @_;
    return map { (split_order_term($_))[0] } $self->_input_order;
}

# A hashref that describes all the special stuff that has to be done
# for various fields if they go into the ORDER BY clause.
sub _special_order {
    my ($self) = @_;
    return $self->{special_order} if $self->{special_order};
    
    my %special_order = %{ SPECIAL_ORDER() };
    my $select_fields = Bugzilla->fields({ type => FIELD_TYPE_SINGLE_SELECT });
    foreach my $field (@$select_fields) {
        next if $field->is_abnormal;
        my $name = $field->name;
        $special_order{$name} = {
            order => ["map_$name.sortkey", "map_$name.value"],
            join  => {
                table => $name,
                from  => "bugs.$name",
                to    => "value",
                join  => 'INNER',
            }
        };
    }
    $self->{special_order} = \%special_order;
    return $self->{special_order};
}

sub _sql_order_by {
    my ($self) = @_;
    if (!$self->{sql_order_by}) {
        my @order_by = map { $self->_translate_order_by_column($_) }
                           $self->_input_order;
        $self->{sql_order_by} = \@order_by;
    }
    return @{ $self->{sql_order_by} };
}

sub _translate_order_by_column {
    my ($self, $order_by_item) = @_;

    my ($field, $direction) = split_order_term($order_by_item);
    
    $direction = '' if lc($direction) eq 'asc';
    my $special_order = $self->_special_order->{$field}->{order};
    # Standard fields have underscores in their SELECT alias instead
    # of a period (because aliases can't have periods).
    $field =~ s/\./_/g;
    my @items = $special_order ? @$special_order : $field;
    if (lc($direction) eq 'desc') {
        @items = map { "$_ DESC" } @items;
    }
    return @items;
}

#############################
# Internal Accessors: LIMIT #
#############################

sub _sql_limit {
    my ($self) = @_;
    my $limit = $self->_params->{limit};
    my $offset = $self->_params->{offset};
    
    my $max_results = Bugzilla->params->{'max_search_results'};
    if (!$self->{allow_unlimited} && (!$limit || $limit > $max_results)) {
        $limit = $max_results;
    }
    
    if (defined($offset) && !$limit) {
        $limit = INT_MAX;
    }
    if (defined $limit) {
        detaint_natural($limit) 
            || ThrowCodeError('param_must_be_numeric', 
                              { function => 'Bugzilla::Search::new',
                                param    => 'limit' });
        if (defined $offset) {
            detaint_natural($offset)
                || ThrowCodeError('param_must_be_numeric',
                                  { function => 'Bugzilla::Search::new',
                                    param    => 'offset' });
        }
        return Bugzilla->dbh->sql_limit($limit, $offset);
    }
    return '';
}

############################
# Internal Accessors: FROM #
############################

sub _column_join {
    my ($self, $field) = @_;
    # The _realname fields require the same join as the username fields.
    $field =~ s/_realname$//;
    my $column_joins = $self->_get_column_joins();
    my $join_info = $column_joins->{$field};
    if ($join_info) {
        # Don't allow callers to modify the constant.
        $join_info = dclone($join_info);
    }
    else {
        if ($self->_multi_select_fields->{$field}) {
            $join_info = { table => "bug_$field" };
        }
    }
    if ($join_info and !$join_info->{as}) {
        $join_info = dclone($join_info);
        $join_info->{as} = "map_$field";
    }
    return $join_info ? $join_info : ();
}

# Sometimes we join the same table more than once. In this case, we
# want to AND all the various critiera that were used in both joins.
sub _combine_joins {
    my ($self, $joins) = @_;
    my @result;
    while(my $join = shift @$joins) {
        my $name = $join->{as};
        my ($others_like_me, $the_rest) = part { $_->{as} eq $name ? 0 : 1 }
                                               @$joins;
        if ($others_like_me) {
            my $from = $join->{from};
            my $to   = $join->{to};
            # Sanity check to make sure that we have the same from and to
            # for all the same-named joins.
            if ($from) {
                all { $_->{from} eq $from } @$others_like_me
                  or die "Not all same-named joins have identical 'from': "
                         . Dumper($join, $others_like_me);
            }
            if ($to) {
                all { $_->{to} eq $to } @$others_like_me
                  or die "Not all same-named joins have identical 'to': "
                         . Dumper($join, $others_like_me);
            }
            
            # We don't need to call uniq here--translate_join will do that
            # for us.
            my @conditions = map { @{ $_->{extra} || [] } }
                                 ($join, @$others_like_me);
            $join->{extra} = \@conditions;
            $joins = $the_rest;
        }
        push(@result, $join);
    }
    
    return @result;
}

# Takes all the "then_to" items and just puts them as the next item in
# the array. Right now this only does one level of "then_to", but we
# could re-write this to handle then_to recursively if we need more levels.
sub _extract_then_to {
    my ($self, $joins) = @_;
    my @result;
    foreach my $join (@$joins) {
        push(@result, $join);
        if (my $then_to = $join->{then_to}) {
            push(@result, $then_to);
        }
    }
    return @result;
}

# JOIN statements for the SELECT and ORDER BY columns. This should not be
# called until the moment it is needed, because _select_columns might be
# modified by the charts.
sub _select_order_joins {
    my ($self) = @_;
    my @joins;
    foreach my $field ($self->_select_columns) {
        my @column_join = $self->_column_join($field);
        push(@joins, @column_join);
    }
    foreach my $field ($self->_input_order_columns) {
        my $join_info = $self->_special_order->{$field}->{join};
        if ($join_info) {
            # Don't let callers modify SPECIAL_ORDER.
            $join_info = dclone($join_info);
            if (!$join_info->{as}) {
                $join_info->{as} = "map_$field";
            }
            push(@joins, $join_info);
        }
    }
    return @joins;
}

# These are the joins that are *always* in the FROM clause.
sub _standard_joins {
    my ($self) = @_;
    my $user = $self->_user;
    my @joins;

    my $security_join = {
        table => 'bug_group_map',
        as    => 'security_map',
    };
    push(@joins, $security_join);

    if ($user->id) {
        $security_join->{extra} =
            ["NOT (" . $user->groups_in_sql('security_map.group_id') . ")"];
            
        my $security_cc_join = {
            table => 'cc',
            as    => 'security_cc',
            extra => ['security_cc.who = ' . $user->id],
        };
        push(@joins, $security_cc_join);
    }
    
    return @joins;
}

sub _sql_from {
    my ($self, $joins_input) = @_;
    my @joins = ($self->_standard_joins, $self->_select_order_joins,
                 @$joins_input);
    @joins = $self->_extract_then_to(\@joins);
    @joins = $self->_combine_joins(\@joins);
    my @join_sql = map { $self->_translate_join($_) } @joins;
    return "bugs\n" . join("\n", @join_sql);
}

# This takes a join data structure and turns it into actual JOIN SQL.
sub _translate_join {
    my ($self, $join_info) = @_;
    
    die "join with no table: " . Dumper($join_info) if !$join_info->{table};
    die "join with no 'as': " . Dumper($join_info) if !$join_info->{as};
        
    my $from_table = "bugs";
    my $from  = $join_info->{from} || "bug_id";
    if ($from =~ /^(\w+)\.(\w+)$/) {
        ($from_table, $from) = ($1, $2);
    }
    my $table = $join_info->{table};
    my $name  = $join_info->{as};
    my $to    = $join_info->{to}    || "bug_id";
    my $join  = $join_info->{join}  || 'LEFT';
    my @extra = @{ $join_info->{extra} || [] };
    $name =~ s/\./_/g;
    
    # If a term contains ORs, we need to put parens around the condition.
    # This is a pretty weak test, but it's actually OK to put parens
    # around too many things.
    @extra = map { $_ =~ /\bOR\b/i ? "($_)" : $_ } @extra;
    my $extra_condition = join(' AND ', uniq @extra);
    if ($extra_condition) {
        $extra_condition = " AND $extra_condition";
    }

    my @join_sql = "$join JOIN $table AS $name"
                        . " ON $from_table.$from = $name.$to$extra_condition";
    return @join_sql;
}

#############################
# Internal Accessors: WHERE #
#############################

# Note: There's also quite a bit of stuff that affects the WHERE clause
# in the "Internal Accessors: Boolean Charts" section.

# The terms that are always in the WHERE clause. These implement bug
# group security.
sub _standard_where {
    my ($self) = @_;
    # If replication lags badly between the shadow db and the main DB,
    # it's possible for bugs to show up in searches before their group
    # controls are properly set. To prevent this, when initially creating
    # bugs we set their creation_ts to NULL, and don't give them a creation_ts
    # until their group controls are set. So if a bug has a NULL creation_ts,
    # it shouldn't show up in searches at all.
    my @where = ('bugs.creation_ts IS NOT NULL');
    
    my $security_term = 'security_map.group_id IS NULL';

    my $user = $self->_user;
    if ($user->id) {
        my $userid = $user->id;
        # This indentation makes the resulting SQL more readable.
        $security_term .= <<END;

        OR (bugs.reporter_accessible = 1 AND bugs.reporter = $userid)
        OR (bugs.cclist_accessible = 1 AND security_cc.who IS NOT NULL)
        OR bugs.assigned_to = $userid
END
        if (Bugzilla->params->{'useqacontact'}) {
            $security_term.= "        OR bugs.qa_contact = $userid";
        }
        $security_term = "($security_term)";
    }

    push(@where, $security_term);

    return @where;
}

sub _sql_where {
    my ($self, $main_clause) = @_;
    # The newline and this particular spacing makes the resulting
    # SQL a bit more readable for debugging.
    my $where = join("\n   AND ", $self->_standard_where);
    my $clause_sql = $main_clause->as_string;
    if ($clause_sql) {
        $where .= "\n   AND " . $clause_sql;
    }
    elsif (!Bugzilla->params->{'search_allow_no_criteria'}
           && !$self->{allow_unlimited})
    {
        ThrowUserError('buglist_parameters_required');
    }
    return $where;
}

################################
# Internal Accessors: GROUP BY #
################################

# And these are the fields that we have to do GROUP BY for in DBs
# that are more strict about putting everything into GROUP BY.
sub _sql_group_by {
    my ($self) = @_;

    # Strict DBs require every element from the SELECT to be in the GROUP BY,
    # unless that element is being used in an aggregate function.
    my @extra_group_by;
    foreach my $column ($self->_select_columns) {
        next if $self->_skip_group_by->{$column};
        my $sql = $self->COLUMNS->{$column}->{name};
        push(@extra_group_by, $sql);
    }

    # And all items from ORDER BY must be in the GROUP BY. The above loop 
    # doesn't catch items that were put into the ORDER BY from SPECIAL_ORDER.
    foreach my $column ($self->_input_order_columns) {
        my $special_order = $self->_special_order->{$column}->{order};
        next if !$special_order;
        push(@extra_group_by, @$special_order);
    }
    
    @extra_group_by = uniq @extra_group_by;
    
    # bug_id is the only field we actually group by.
    return ('bugs.bug_id', join(',', @extra_group_by));
}

# A helper for _sql_group_by.
sub _skip_group_by {
    my ($self) = @_;
    return $self->{skip_group_by} if $self->{skip_group_by};
    my @skip_list = GROUP_BY_SKIP;
    push(@skip_list, keys %{ $self->_multi_select_fields });
    my %skip_hash = map { $_ => 1 } @skip_list;
    $self->{skip_group_by} = \%skip_hash;
    return $self->{skip_group_by};
}

##############################################
# Internal Accessors: Special Params Parsing #
##############################################

# Backwards compatibility for old field names.
sub _convert_old_params {
    my ($self) = @_;
    my $params = $self->_params;
    
    # bugidtype has different values in modern Search.pm.
    if (defined $params->{'bugidtype'}) {
        my $value = $params->{'bugidtype'};
        $params->{'bugidtype'} = $value eq 'exclude' ? 'nowords' : 'anyexact';
    }
    
    foreach my $old_name (keys %{ FIELD_MAP() }) {
        if (defined $params->{$old_name}) {
            my $new_name = FIELD_MAP->{$old_name};
            $params->{$new_name} = delete $params->{$old_name};
        }
    }
}

# This parses all the standard search parameters except for the boolean
# charts.
sub _special_charts {
    my ($self) = @_;
    $self->_convert_old_params();
    $self->_special_parse_bug_status();
    $self->_special_parse_resolution();
    my $clause = new Bugzilla::Search::Clause();
    $clause->add( $self->_parse_basic_fields()     );
    $clause->add( $self->_special_parse_email()    );
    $clause->add( $self->_special_parse_chfield()  );
    $clause->add( $self->_special_parse_deadline() );
    return $clause;
}

sub _parse_basic_fields {
    my ($self) = @_;
    my $params = $self->_params;
    my $chart_fields = $self->_chart_fields;
    
    my $clause = new Bugzilla::Search::Clause();
    foreach my $field_name (keys %$chart_fields) {
        # CGI params shouldn't have periods in them, so we only accept
        # period-separated fields with underscores where the periods go.
        my $param_name = $field_name;
        $param_name =~ s/\./_/g;
        my @values = $self->_param_array($param_name);
        next if !@values;
        my $default_op = $param_name eq 'content' ? 'matches' : 'anyexact';
        my $operator = $params->{"${param_name}_type"} || $default_op;
        # Fields that are displayed as multi-selects are passed as arrays,
        # so that they can properly search values that contain commas.
        # However, other fields are sent as strings, so that they are properly
        # split on commas if required.
        my $field = $chart_fields->{$field_name};
        my $pass_value;
        if ($field->is_select or $field->name eq 'version'
            or $field->name eq 'target_milestone')
        {
            $pass_value = \@values;
        }
        else {
            $pass_value = join(',', @values);
        }
        $clause->add($field_name, $operator, $pass_value);
    }
    return $clause;
}

sub _special_parse_bug_status {
    my ($self) = @_;
    my $params = $self->_params;
    return if !defined $params->{'bug_status'};
    # We want to allow the bug_status_type parameter to work normally,
    # meaning that this special code should only be activated if we are
    # doing the normal "anyexact" search on bug_status.
    return if (defined $params->{'bug_status_type'}
               and $params->{'bug_status_type'} ne 'anyexact');

    my @bug_status = $self->_param_array('bug_status');
    # Also include inactive bug statuses, as you can query them.
    my $legal_statuses = $self->_chart_fields->{'bug_status'}->legal_values;

    # If the status contains __open__ or __closed__, translate those
    # into their equivalent lists of open and closed statuses.
    if (grep { $_ eq '__open__' } @bug_status) {
        my @open = grep { $_->is_open } @$legal_statuses;
        @open = map { $_->name } @open;
        push(@bug_status, @open);
    }
    if (grep { $_ eq '__closed__' } @bug_status) {
        my @closed = grep { not $_->is_open } @$legal_statuses;
        @closed = map { $_->name } @closed;
        push(@bug_status, @closed);
    }

    @bug_status = uniq @bug_status;
    my $all = grep { $_ eq "__all__" } @bug_status;
    # This will also handle removing __open__ and __closed__ for us
    # (__all__ too, which is why we check for it above, first).
    @bug_status = _valid_values(\@bug_status, $legal_statuses);

    # If the user has selected every status, change to selecting none.
    # This is functionally equivalent, but quite a lot faster.
    if ($all or scalar(@bug_status) == scalar(@$legal_statuses)) {
        delete $params->{'bug_status'};
    }
    else {
        $params->{'bug_status'} = \@bug_status;
    }
}

sub _special_parse_chfield {
    my ($self) = @_;
    my $params = $self->_params;
    
    my $date_from = trim(lc($params->{'chfieldfrom'} || ''));
    my $date_to = trim(lc($params->{'chfieldto'} || ''));
    $date_from = '' if $date_from eq 'now';
    $date_to = '' if $date_to eq 'now';
    my @fields = $self->_param_array('chfield');
    my $value_to = $params->{'chfieldvalue'};
    $value_to = '' if !defined $value_to;

    @fields = map { $_ eq '[Bug creation]' ? 'creation_ts' : $_ } @fields;

    my $clause = new Bugzilla::Search::Clause();

    # It is always safe and useful to push delta_ts into the charts
    # if there is a "from" date specified. It doesn't conflict with
    # searching [Bug creation], because a bug's delta_ts is set to
    # its creation_ts when it is created. So this just gives the
    # database an additional index to possibly choose, on a table that
    # is smaller than bugs_activity.
    if ($date_from ne '') {
        $clause->add('delta_ts', 'greaterthaneq', $date_from);
    }
    # It's not normally safe to do it for "to" dates, though--"chfieldto" means
    # "a field that changed before this date", and delta_ts could be either
    # later or earlier than that, if we're searching for the time that a field
    # changed. However, chfieldto all by itself, without any chfieldvalue or
    # chfield, means "just search delta_ts", and so we still want that to
    # work.
    if ($date_to ne '' and !@fields and $value_to eq '') {
        $clause->add('delta_ts', 'lessthaneq', $date_to);
    }

    # Basically, we construct the chart like:
    #
    # (added_for_field1 = value OR added_for_field2 = value)
    # AND (date_field1_changed >= date_from OR date_field2_changed >= date_from)
    # AND (date_field1_changed <= date_to OR date_field2_changed <= date_to)
    #
    # Theoretically, all we *really* would need to do is look for the field id
    # in the bugs_activity table, because we've already limited the search
    # by delta_ts above, but there's no chart to do that, so we check the
    # change date of the fields.
    
    if ($value_to ne '') {
        my $value_clause = new Bugzilla::Search::Clause('OR');
        foreach my $field (@fields) {
            $value_clause->add($field, 'changedto', $value_to);
        }
        $clause->add($value_clause);
    }

    if ($date_from ne '') {
        my $from_clause = new Bugzilla::Search::Clause('OR');
        foreach my $field (@fields) {
            $from_clause->add($field, 'changedafter', $date_from);
        }
        $clause->add($from_clause);
    }
    if ($date_to ne '') {
        # chfieldto is supposed to be a relative date or a date of the form
        # YYYY-MM-DD, i.e. without the time appended to it. We append the
        # time ourselves so that the end date is correctly taken into account.
        $date_to .= ' 23:59:59' if $date_to =~ /^\d{4}-\d{1,2}-\d{1,2}$/;

        my $to_clause = new Bugzilla::Search::Clause('OR');
        foreach my $field (@fields) {
            $to_clause->add($field, 'changedbefore', $date_to);
        }
        $clause->add($to_clause);
    }

    return $clause;
}

sub _special_parse_deadline {
    my ($self) = @_;
    return if !$self->_user->is_timetracker;
    my $params = $self->_params;
    
    my $clause = new Bugzilla::Search::Clause();
    if (my $from = $params->{'deadlinefrom'}) {
        $clause->add('deadline', 'greaterthaneq', $from);
    }
    if (my $to = $params->{'deadlineto'}) {
        $clause->add('deadline', 'lessthaneq', $to);
    }
    
    return $clause;
}

sub _special_parse_email {
    my ($self) = @_;
    my $params = $self->_params;
    
    my @email_params = grep { $_ =~ /^email\d+$/ } keys %$params;
    
    my $clause = new Bugzilla::Search::Clause();
    foreach my $param (@email_params) {
        $param =~ /(\d+)$/;
        my $id = $1;
        my $email = trim($params->{"email$id"});
        next if !$email;
        my $type = $params->{"emailtype$id"} || 'anyexact';
        $type = "anyexact" if $type eq "exact";

        my $or_clause = new Bugzilla::Search::Clause('OR');
        foreach my $field (qw(assigned_to reporter cc qa_contact)) {
            if ($params->{"email$field$id"}) {
                $or_clause->add($field, $type, $email);
            }
        }
        if ($params->{"emaillongdesc$id"}) {
            $or_clause->add("commenter", $type, $email);
        }
        
        $clause->add($or_clause);
    }
    
    return $clause;
}

sub _special_parse_resolution {
    my ($self) = @_;
    my $params = $self->_params;
    return if !defined $params->{'resolution'};

    my @resolution = $self->_param_array('resolution');
    my $legal_resolutions = $self->_chart_fields->{resolution}->legal_values;
    @resolution = _valid_values(\@resolution, $legal_resolutions, '---');
    if (scalar(@resolution) == scalar(@$legal_resolutions)) {
        delete $params->{'resolution'};
    }
}

sub _valid_values {
    my ($input, $valid, $extra_value) = @_;
    my @result;
    foreach my $item (@$input) {
        $item = trim($item);
        if (defined $extra_value and $item eq $extra_value) {
            push(@result, $item);
        }
        elsif (grep { $_->name eq $item } @$valid) {
            push(@result, $item);
        }
    }
    return @result;
}

######################################
# Internal Accessors: Boolean Charts #
######################################

sub _charts_to_conditions {
    my ($self) = @_;
    
    my $clause = $self->_charts;
    my @joins;
    $clause->walk_conditions(sub {
        my ($condition) = @_;
        return if !$condition->translated;
        push(@joins, @{ $condition->translated->{joins} });
    });
    return (\@joins, $clause);
}

sub _charts {
    my ($self) = @_;
    
    my $clause = $self->_params_to_data_structure();
    my $chart_id = 0;
    $clause->walk_conditions(sub { $self->_handle_chart($chart_id++, @_) });
    return $clause;
}

sub _params_to_data_structure {
    my ($self) = @_;
    
    # First we get the "special" charts, representing all the normal
    # field son the search page. This may modify _params, so it needs to
    # happen first.
    my $clause = $self->_special_charts;

    # Then we process the old Boolean Charts input format.
    $clause->add( $self->_boolean_charts );
    
    # And then process the modern "custom search" format.
    $clause->add( $self->_custom_search );
   
    return $clause;
}

sub _boolean_charts {
    my ($self) = @_;
    
    my $params = $self->_params;
    my @param_list = keys %$params;
    
    my @all_field_params = grep { /^field-?\d+/ } @param_list;
    my @chart_ids = map { /^field(-?\d+)/; $1 } @all_field_params;
    @chart_ids = sort { $a <=> $b } uniq @chart_ids;
    
    my $clause = new Bugzilla::Search::Clause();
    foreach my $chart_id (@chart_ids) {
        my @all_and = grep { /^field$chart_id-\d+/ } @param_list;
        my @and_ids = map { /^field$chart_id-(\d+)/; $1 } @all_and;
        @and_ids = sort { $a <=> $b } uniq @and_ids;
        
        my $and_clause = new Bugzilla::Search::Clause();
        foreach my $and_id (@and_ids) {
            my @all_or = grep { /^field$chart_id-$and_id-\d+/ } @param_list;
            my @or_ids = map { /^field$chart_id-$and_id-(\d+)/; $1 } @all_or;
            @or_ids = sort { $a <=> $b } uniq @or_ids;
            
            my $or_clause = new Bugzilla::Search::Clause('OR');
            foreach my $or_id (@or_ids) {
                my $identifier = "$chart_id-$and_id-$or_id";
                my $field = $params->{"field$identifier"};
                my $operator = $params->{"type$identifier"};
                my $value = $params->{"value$identifier"};                
                $or_clause->add($field, $operator, $value);
            }
            $and_clause->add($or_clause);
            $and_clause->negate(1) if $params->{"negate$chart_id"};
        }
        $clause->add($and_clause);
    }
    
    return $clause;
}

sub _custom_search {
    my ($self) = @_;
    my $params = $self->_params;

    my $current_clause = new Bugzilla::Search::Clause($params->{j_top});
    my @clause_stack;
    foreach my $id ($self->_field_ids) {
        my $field = $params->{"f$id"};
        if ($field eq 'OP') {
            my $joiner = $params->{"j$id"};
            my $new_clause = new Bugzilla::Search::Clause($joiner);
            $new_clause->negate($params->{"n$id"});
            $current_clause->add($new_clause);
            push(@clause_stack, $current_clause);
            $current_clause = $new_clause;
            next;
        }
        if ($field eq 'CP') {
            $current_clause = pop @clause_stack;
            ThrowCodeError('search_cp_without_op', { id => $id })
                if !$current_clause;
            next;
        }
        
        my $operator = $params->{"o$id"};
        my $value = $params->{"v$id"};
        my $condition = condition($field, $operator, $value);
        $condition->negate($params->{"n$id"});
        $current_clause->add($condition);
    }
    
    # We allow people to specify more OPs than CPs, so at the end of the
    # loop our top clause may be still in the stack instead of being
    # $current_clause.
    return $clause_stack[0] || $current_clause;
}

sub _field_ids {
    my ($self) = @_;
    my $params = $self->_params;
    my @param_list = keys %$params;
    
    my @field_params = grep { /^f\d+$/ } @param_list;
    my @field_ids = map { /(\d+)/; $1 } @field_params;
    @field_ids = sort { $a <=> $b } @field_ids;
    return @field_ids;
}

sub _handle_chart {
    my ($self, $chart_id, $condition) = @_;
    my $dbh = Bugzilla->dbh;
    my $params = $self->_params;
    my ($field, $operator, $value) = $condition->fov;

    $field = FIELD_MAP->{$field} || $field;

    return if (!defined $field or !defined $operator or !defined $value);
    
    my $string_value;
    if (ref $value eq 'ARRAY') {
        # Trim input and ignore blank values.
        @$value = map { trim($_) } @$value;
        @$value = grep { defined $_ and $_ ne '' } @$value;
        return if !@$value;
        $string_value = join(',', @$value);
    }
    else {
        return if $value eq '';
        $string_value = $value;
    }
    
    $self->_chart_fields->{$field}
        or ThrowCodeError("invalid_field_name", { field => $field });
    trick_taint($field);
    
    # This is the field as you'd reference it in a SQL statement.
    my $full_field = $field =~ /\./ ? $field : "bugs.$field";

    # "value" and "quoted" are for search functions that always operate
    # on a scalar string and never care if they were passed multiple
    # parameters. If the user does pass multiple parameters, they will
    # become a space-separated string for those search functions.
    #
    # all_values is for search functions that do operate
    # on multiple values, like anyexact.
    
    my %search_args = (
        chart_id   => $chart_id,
        sequence   => $chart_id,
        field      => $field,
        full_field => $full_field,
        operator   => $operator,
        value      => $string_value,
        all_values => $value,
        joins      => [],
    );
    $search_args{quoted} = $self->_quote_unless_numeric(\%search_args);
    # This should add a "term" selement to %search_args.
    $self->do_search_function(\%search_args);

    # If term is left empty, then this means the criteria
    # has no effect and can be ignored.
    return unless $search_args{term};

    # All the things here that don't get pulled out of
    # %search_args are their original values before
    # do_search_function modified them.   
    $self->search_description({
        field => $field, type => $operator,
        value => $string_value, term => $search_args{term},
    });
    
    $condition->translated(\%search_args);
}

##################################
# do_search_function And Helpers #
##################################

# This takes information about the current boolean chart and translates
# it into SQL, using the constants at the top of this file.
sub do_search_function {
    my ($self, $args) = @_;
    my ($field, $operator) = @$args{qw(field operator)};
    
    if (my $parse_func = SPECIAL_PARSING->{$field}) {
        $self->$parse_func($args);
        # Some parsing functions set $term, though most do not.
        # For the ones that set $term, we don't need to do any further
        # parsing.
        return if $args->{term};
    }
    
    my $operator_field_override = $self->_get_operator_field_override();
    my $override = $operator_field_override->{$field};
    # Attachment fields get special handling, if they don't have a specific
    # individual override.
    if (!$override and $field =~ /^attachments\./) {
        $override = $operator_field_override->{attachments};
    }
    # If there's still no override, check for an override on the field's type.
    if (!$override) {
        my $field_obj = $self->_chart_fields->{$field};
        $override = $operator_field_override->{$field_obj->type};
    }
    
    if ($override) {
        my $search_func = $self->_pick_override_function($override, $operator);
        $self->$search_func($args) if $search_func;
    }

    # Some search functions set $term, and some don't. For the ones that
    # don't (or for fields that don't have overrides) we now call the
    # direct operator function from OPERATORS.
    if (!defined $args->{term}) {
        $self->_do_operator_function($args);
    }
    
    if (!defined $args->{term}) {
        # This field and this type don't work together. Generally,
        # this should never be reached, because it should be handled
        # explicitly by OPERATOR_FIELD_OVERRIDE.
        ThrowUserError("search_field_operator_invalid",
                       { field => $field, operator => $operator });
    }
}

# A helper for various search functions that need to run operator
# functions directly.
sub _do_operator_function {
    my ($self, $func_args) = @_;
    my $operator = $func_args->{operator};
    my $operator_func = OPERATORS->{$operator}
      || ThrowCodeError("search_field_operator_unsupported",
                        { operator => $operator });
    $self->$operator_func($func_args);
}

sub _reverse_operator {
    my ($self, $operator) = @_;
    my $reverse = OPERATOR_REVERSE->{$operator};
    return $reverse if $reverse;
    if ($operator =~ s/^not//) {
        return $operator;
    }
    return "not$operator";
}

sub _pick_override_function {
    my ($self, $override, $operator) = @_;
    my $search_func = $override->{$operator};

    if (!$search_func) {
        # If we don't find an override for one specific operator,
        # then there are some special override types:
        # _non_changed: For any operator that doesn't have the word
        #               "changed" in it
        # _default: Overrides all operators that aren't explicitly specified.
        if ($override->{_non_changed} and $operator !~ /changed/) {
            $search_func = $override->{_non_changed};
        }
        elsif ($override->{_default}) {
            $search_func = $override->{_default};
        }
    }

    return $search_func;
}

sub _get_operator_field_override {
    my $self = shift;
    my $cache = Bugzilla->request_cache;

    return $cache->{operator_field_override} 
        if defined $cache->{operator_field_override};

    my %operator_field_override = %{ OPERATOR_FIELD_OVERRIDE() };
    Bugzilla::Hook::process('search_operator_field_override',
                            { search => $self, 
                              operators => \%operator_field_override });

    $cache->{operator_field_override} = \%operator_field_override;
    return $cache->{operator_field_override};
}

sub _get_column_joins {
    my $self = shift;
    my $cache = Bugzilla->request_cache;

    return $cache->{column_joins} if defined $cache->{column_joins};

    my %column_joins = %{ COLUMN_JOINS() };
    Bugzilla::Hook::process('buglist_column_joins',
                            { column_joins => \%column_joins });

    $cache->{column_joins} = \%column_joins;
    return $cache->{column_joins};
}

###########################
# Search Function Helpers #
###########################

# When we're doing a numeric search against a numeric column, we want to
# just put a number into the SQL instead of a string. On most DBs, this
# is just a performance optimization, but on SQLite it actually changes
# the behavior of some searches.
sub _quote_unless_numeric {
    my ($self, $args, $value) = @_;
    if (!defined $value) {
        $value = $args->{value};
    }
    my ($field, $operator) = @$args{qw(field operator)};
    
    my $numeric_operator = !grep { $_ eq $operator } NON_NUMERIC_OPERATORS;
    my $numeric_field = $self->_chart_fields->{$field}->is_numeric;
    my $numeric_value = ($value =~ NUMBER_REGEX) ? 1 : 0;
    my $is_numeric = $numeric_operator && $numeric_field && $numeric_value;
    if ($is_numeric) {
        my $quoted = $value;
        trick_taint($quoted);
        return $quoted;
    }
    return Bugzilla->dbh->quote($value);
}

sub build_subselect {
    my ($outer, $inner, $table, $cond) = @_;
    return "$outer IN (SELECT $inner FROM $table WHERE $cond)";
}

# Used by anyexact to get the list of input values. This allows us to
# support values with commas inside of them in the standard charts, and
# still accept string values for the boolean charts (and split them on
# commas).
sub _all_values {
    my ($self, $args, $split_on) = @_;
    $split_on ||= qr/[\s,]+/;
    my $dbh = Bugzilla->dbh;
    my $all_values = $args->{all_values};
    
    my @array;
    if (ref $all_values eq 'ARRAY') {
        @array = @$all_values;
    }
    else {
        @array = split($split_on, $all_values);
        @array = map { trim($_) } @array;
        @array = grep { defined $_ and $_ ne '' } @array;
    }
    
    if ($args->{field} eq 'resolution') {
        @array = map { $_ eq '---' ? '' : $_ } @array;
    }
    
    return @array;
}

# Support for "any/all/nowordssubstr" comparison type ("words as substrings")
sub _substring_terms {
    my ($self, $args) = @_;
    my $dbh = Bugzilla->dbh;

    # We don't have to (or want to) use _all_values, because we'd just
    # split each term on spaces and commas anyway.
    my @words = split(/[\s,]+/, $args->{value});
    @words = grep { defined $_ and $_ ne '' } @words;
    @words = map { $dbh->quote($_) } @words;
    my @terms = map { $dbh->sql_iposition($_, $args->{full_field}) . " > 0" }
                    @words;
    return @terms;
}

sub _word_terms {
    my ($self, $args) = @_;
    my $dbh = Bugzilla->dbh;
    
    my @values = split(/[\s,]+/, $args->{value});
    @values = grep { defined $_ and $_ ne '' } @values;
    my @substring_terms = $self->_substring_terms($args);
    
    my @terms;
    my $start = $dbh->WORD_START;
    my $end   = $dbh->WORD_END;
    foreach my $word (@values) {
        my $regex  = $start . quotemeta($word) . $end;
        my $quoted = $dbh->quote($regex);
        # We don't have to check the regexp, because we escaped it, so we're
        # sure it's valid.
        my $regex_term = $dbh->sql_regexp($args->{full_field}, $quoted,
                                          'no check');
        # Regular expressions are slow--substring searches are faster.
        # If we're searching for a word, we're also certain that the
        # substring will appear in the value. So we limit first by
        # substring and then by a regex that will match just words.
        my $substring_term = shift @substring_terms;
        push(@terms, "$substring_term AND $regex_term");
    }
    
    return @terms;
}

#####################################
# "Special Parsing" Functions: Date #
#####################################

sub _timestamp_translate {
    my ($self, $args) = @_;
    my $value = $args->{value};
    my $dbh = Bugzilla->dbh;

    return if $value !~ /^(?:[\+\-]?\d+[hdwmy]s?|now)$/i;

    # By default, the time is appended to the date, which we don't want
    # for deadlines.
    $value = SqlifyDate($value);
    if ($args->{field} eq 'deadline') {
        ($value) = split(/\s/, $value);
    }
    $args->{value} = $value;
    $args->{quoted} = $dbh->quote($value);
}

sub SqlifyDate {
    my ($str) = @_;
    my $fmt = "%Y-%m-%d %H:%M:%S";
    $str = "" if (!defined $str || lc($str) eq 'now');
    if ($str eq "") {
        my ($sec, $min, $hour, $mday, $month, $year, $wday) = localtime(time());
        return sprintf("%4d-%02d-%02d 00:00:00", $year+1900, $month+1, $mday);
    }

    if ($str =~ /^(-|\+)?(\d+)([hdwmy])(s?)$/i) {   # relative date
        my ($sign, $amount, $unit, $startof, $date) = ($1, $2, lc $3, lc $4, time);
        my ($sec, $min, $hour, $mday, $month, $year, $wday)  = localtime($date);
        if ($sign && $sign eq '+') { $amount = -$amount; }
        $startof = 1 if $amount == 0;
        if ($unit eq 'w') {                  # convert weeks to days
            $amount = 7*$amount;
            $amount += $wday if $startof;
            $unit = 'd';
        }
        if ($unit eq 'd') {
            if ($startof) {
              $fmt = "%Y-%m-%d 00:00:00";
              $date -= $sec + 60*$min + 3600*$hour;
            }
            $date -= 24*3600*$amount;
            return time2str($fmt, $date);
        }
        elsif ($unit eq 'y') {
            if ($startof) {
                return sprintf("%4d-01-01 00:00:00", $year+1900-$amount);
            } 
            else {
                return sprintf("%4d-%02d-%02d %02d:%02d:%02d", 
                               $year+1900-$amount, $month+1, $mday, $hour, $min, $sec);
            }
        }
        elsif ($unit eq 'm') {
            $month -= $amount;
            while ($month<0) { $year--; $month += 12; }
            if ($startof) {
                return sprintf("%4d-%02d-01 00:00:00", $year+1900, $month+1);
            }
            else {
                return sprintf("%4d-%02d-%02d %02d:%02d:%02d", 
                               $year+1900, $month+1, $mday, $hour, $min, $sec);
            }
        }
        elsif ($unit eq 'h') {
            # Special case for 'beginning of an hour'
            if ($startof) {
                $fmt = "%Y-%m-%d %H:00:00";
            } 
            $date -= 3600*$amount;
            return time2str($fmt, $date);
        }
        return undef;                      # should not happen due to regexp at top
    }
    my $date = str2time($str);
    if (!defined($date)) {
        ThrowUserError("illegal_date", { date => $str });
    }
    return time2str($fmt, $date);
}

######################################
# "Special Parsing" Functions: Users #
######################################

sub pronoun {
    my ($noun, $user) = (@_);
    if ($noun eq "%user%") {
        if ($user->id) {
            return $user->id;
        } else {
            ThrowUserError('login_required_for_pronoun');
        }
    }
    if ($noun eq "%reporter%") {
        return "bugs.reporter";
    }
    if ($noun eq "%assignee%") {
        return "bugs.assigned_to";
    }
    if ($noun eq "%qacontact%") {
        return "COALESCE(bugs.qa_contact,0)";
    }
    return 0;
}

sub _contact_pronoun {
    my ($self, $args) = @_;
    my $value = $args->{value};
    my $user = $self->_user;

    if ($value =~ /^\%group\.[^%]+%$/) {
        $self->_contact_exact_group($args);
    }
    elsif ($value =~ /^(%\w+%)$/) {
        $args->{value} = pronoun($1, $user);
        $args->{quoted} = $args->{value};
        $args->{value_is_id} = 1;
    }
}

sub _contact_exact_group {
    my ($self, $args) = @_;
    my ($value, $operator, $field, $chart_id, $joins) =
        @$args{qw(value operator field chart_id joins)};
    my $dbh = Bugzilla->dbh;
    my $user = $self->_user;
    
    # We already know $value will match this regexp, else we wouldn't be here.
    $value =~ /\%group\.([^%]+)%/;
    my $group_name = $1;
    my $group = Bugzilla::Group->check({ name => $group_name, _error => 'invalid_group_name' });
    # Pass $group_name instead of $group->name to the error message
    # to not leak the existence of the group.
    $user->in_group($group)
      || ThrowUserError('invalid_group_name', { name => $group_name });
    # Now that we know the user belongs to this group, it's safe
    # to disclose more information.
    $group->check_members_are_visible();

    my $group_ids = Bugzilla::Group->flatten_group_membership($group->id);
    my $table = "user_group_map_$chart_id";
    my $join = {
        table => 'user_group_map',
        as    => $table,
        from  => $field,
        to    => 'user_id',
        extra => [$dbh->sql_in("$table.group_id", $group_ids),
                  "$table.isbless = 0"],
    };
    push(@$joins, $join);
    if ($operator =~ /^not/) {
        $args->{term} = "$table.group_id IS NULL";
    }
    else {
        $args->{term} = "$table.group_id IS NOT NULL";
    }
}

sub _cc_pronoun {
    my ($self, $args) = @_;
    my ($full_field, $value) = @$args{qw(full_field value)};
    my $user = $self->_user;

    if ($value =~ /\%group/) {
        return $self->_cc_exact_group($args);
    }
    elsif ($value =~ /^(%\w+%)$/) {
        $args->{value} = pronoun($1, $user);
        $args->{quoted} = $args->{value};
        $args->{value_is_id} = 1;
    }
}

sub _cc_exact_group {
    my ($self, $args) = @_;
    my ($chart_id, $sequence, $joins, $operator, $value) =
        @$args{qw(chart_id sequence joins operator value)};
    my $user = $self->_user;
    my $dbh = Bugzilla->dbh;
    
    $value =~ m/%group\.([^%]+)%/;
    my $group = Bugzilla::Group->check({ name => $1, _error => 'invalid_group_name' });
    $group->check_members_are_visible();
    $user->in_group($group)
      || ThrowUserError('invalid_group_name', {name => $group->name});

    my $all_groups = Bugzilla::Group->flatten_group_membership($group->id);

    # This is for the email1, email2, email3 fields from query.cgi.
    if ($chart_id eq "") {
        $chart_id = "CC$$sequence";
        $args->{sequence}++;
    }
    
    my $cc_table = "cc_$chart_id";
    push(@$joins, { table => 'cc', as => $cc_table });
    my $group_table = "user_group_map_$chart_id";
    my $group_join = {
        table => 'user_group_map',
        as    => $group_table,
        from  => "$cc_table.who",
        to    => 'user_id',
        extra => [$dbh->sql_in("$group_table.group_id", $all_groups),
                  "$group_table.isbless = 0"],
    };
    push(@$joins, $group_join);

    if ($operator =~ /^not/) {
        $args->{term} = "$group_table.group_id IS NULL";
    }
    else {
        $args->{term} = "$group_table.group_id IS NOT NULL";
    }
}

# XXX This should probably be merged with cc_pronoun.
sub _commenter_pronoun {
    my ($self, $args) = @_;
    my $value = $args->{value};
    my $user = $self->_user;

    if ($value =~ /^(%\w+%)$/) {
        $args->{value} = pronoun($1, $user);
        $args->{quoted} = $args->{value};
        $args->{value_is_id} = 1;
    }
}

#####################################################################
# Search Functions
#####################################################################

sub _invalid_combination {
    my ($self, $args) = @_;
    my ($field, $operator) = @$args{qw(field operator)};
    ThrowUserError('search_field_operator_invalid',
                   { field => $field, operator => $operator });
}

# For all the "user" fields--assigned_to, reporter, qa_contact,
# cc, commenter, requestee, etc.
sub _user_nonchanged {
    my ($self, $args) = @_;
    my ($field, $operator, $chart_id, $sequence, $joins) =
        @$args{qw(field operator chart_id sequence joins)};

    my $is_in_other_table;
    if (my $join = USER_FIELDS->{$field}->{join}) {
        $is_in_other_table = 1;
        my $as = "${field}_$chart_id";
        # Needed for setters.login_name and requestees.login_name.
        # Otherwise when we try to join "profiles" below, we'd get
        # something like "setters.login_name.login_name" in the "from".
        $as =~ s/\./_/g;        
        # This helps implement the email1, email2, etc. parameters.
        if ($chart_id =~ /default/) {
            $as .= "_$sequence";
        }
        my $isprivate = USER_FIELDS->{$field}->{isprivate};
        my $extra = ($isprivate and !$self->_user->is_insider)
                    ? ["$as.isprivate = 0"] : [];
        # We want to copy $join so as not to modify USER_FIELDS.
        push(@$joins, { %$join, as => $as, extra => $extra });
        my $search_field = USER_FIELDS->{$field}->{field};
        $args->{full_field} = "$as.$search_field";
    }

    my $is_nullable = USER_FIELDS->{$field}->{nullable};
    my $null_alternate = "''";
    # When using a pronoun, we use the userid, and we don't have to
    # join the profiles table.
    if ($args->{value_is_id}) {
        $null_alternate = 0;
    }
    else {
        my $as = "name_${field}_$chart_id";
        # For fields with periods in their name.
        $as =~ s/\./_/;
        my $join = {
            table => 'profiles',
            as    => $as,
            from  => $args->{full_field},
            to    => 'userid',
            join  => (!$is_in_other_table and !$is_nullable) ? 'INNER' : undef,
        };
        push(@$joins, $join);
        $args->{full_field} = "$as.login_name";
    }
    
    # We COALESCE fields that can be NULL, to make "not"-style operators
    # continue to work properly. For example, "qa_contact is not equal to bob"
    # should also show bugs where the qa_contact is NULL. With COALESCE,
    # it does.
    if ($is_nullable) {
        $args->{full_field} = "COALESCE($args->{full_field}, $null_alternate)";
    }
    
    # For fields whose values are stored in other tables, negation (NOT)
    # only works properly if we put the condition into the JOIN instead
    # of the WHERE.
    if ($is_in_other_table) {
        # Using the last join works properly whether we're searching based
        # on userid or login_name.
        my $last_join = $joins->[-1];
        
        # For negative operators, the system we're using here
        # only works properly if we reverse the operator and check IS NULL
        # in the WHERE.
        my $is_negative = $operator =~ /^no/ ? 1 : 0;
        if ($is_negative) {
            $args->{operator} = $self->_reverse_operator($operator);
        }
        $self->_do_operator_function($args);
        push(@{ $last_join->{extra} }, $args->{term});
        
        # For login_name searches, we only want a single join.
        # So we create a subselect table out of our two joins. This makes
        # negation (NOT) work properly for values that are in other
        # tables.
        if ($last_join->{table} eq 'profiles') {
            pop @$joins;
            $last_join->{join} = 'INNER';
            my ($join_sql) = $self->_translate_join($last_join);
            my $first_join = $joins->[-1];
            my $as = $first_join->{as};            
            my $table = $first_join->{table};
            my $columns = "bug_id";
            $columns .= ",isprivate" if @{ $first_join->{extra} };
            my $new_table = "SELECT DISTINCT $columns FROM $table AS $as $join_sql";
            $first_join->{table} = "($new_table)";
            # We always want to LEFT JOIN the generated table.
            delete $first_join->{join};
            # To support OR charts, we need multiple tables.
            my $new_as = $first_join->{as} . "_$sequence";
            $_ =~ s/\Q$as\E/$new_as/ foreach @{ $first_join->{extra} };
            $first_join->{as} = $new_as;
            $last_join = $first_join;
        }
        
        # If we're joining the first table (we're using a pronoun and
        # searching by user id) then we need to check $other_table->{field}.
        my $check_field = $last_join->{as} . '.bug_id';
        if ($is_negative) {
            $args->{term} = "$check_field IS NULL";
        }
        else {
            $args->{term} = "$check_field IS NOT NULL";
        }
    }
}

# XXX This duplicates having Commenter as a search field.
sub _long_desc_changedby {
    my ($self, $args) = @_;
    my ($chart_id, $joins, $value) = @$args{qw(chart_id joins value)};
    
    my $table = "longdescs_$chart_id";
    push(@$joins, { table => 'longdescs', as => $table });
    my $user_id = login_to_id($value, THROW_ERROR);
    $args->{term} = "$table.who = $user_id";
}

sub _long_desc_changedbefore_after {
    my ($self, $args) = @_;
    my ($chart_id, $operator, $value, $joins) =
        @$args{qw(chart_id operator value joins)};
    my $dbh = Bugzilla->dbh;
    
    my $sql_operator = ($operator =~ /before/) ? '<=' : '>=';
    my $table = "longdescs_$chart_id";
    my $sql_date = $dbh->quote(SqlifyDate($value));
    my $join = {
        table => 'longdescs',
        as    => $table,
        extra => ["$table.bug_when $sql_operator $sql_date"],
    };
    push(@$joins, $join);
    $args->{term} = "$table.bug_when IS NOT NULL";

    # If the user is not part of the insiders group, they cannot see
    # private comments
    if (!$self->_user->is_insider) {
        $args->{term} .= " AND $table.isprivate = 0";
    }
}

sub _content_matches {
    my ($self, $args) = @_;
    my ($chart_id, $joins, $fields, $operator, $value) =
        @$args{qw(chart_id joins fields operator value)};
    my $dbh = Bugzilla->dbh;
    
    # "content" is an alias for columns containing text for which we
    # can search a full-text index and retrieve results by relevance, 
    # currently just bug comments (and summaries to some degree).
    # There's only one way to search a full-text index, so we only
    # accept the "matches" operator, which is specific to full-text
    # index searches.

    # Add the fulltext table to the query so we can search on it.
    my $table = "bugs_fulltext_$chart_id";
    my $comments_col = "comments";
    $comments_col = "comments_noprivate" unless $self->_user->is_insider;
    push(@$joins, { table => 'bugs_fulltext', as => $table });
    
    # Create search terms to add to the SELECT and WHERE clauses.
    my ($term1, $rterm1) =
        $dbh->sql_fulltext_search("$table.$comments_col", $value);
    my ($term2, $rterm2) =
        $dbh->sql_fulltext_search("$table.short_desc", $value);
    $rterm1 = $term1 if !$rterm1;
    $rterm2 = $term2 if !$rterm2;

    # The term to use in the WHERE clause.
    my $term = "$term1 OR $term2";
    if ($operator =~ /not/i) {
        $term = "NOT($term)";
    }
    $args->{term} = $term;
    
    # In order to sort by relevance (in case the user requests it),
    # we SELECT the relevance value so we can add it to the ORDER BY
    # clause. Every time a new fulltext chart isadded, this adds more 
    # terms to the relevance sql.
    #
    # We build the relevance SQL by modifying the COLUMNS list directly,
    # which is kind of a hack but works.
    my $current = $self->COLUMNS->{'relevance'}->{name};
    $current = $current ? "$current + " : '';
    # For NOT searches, we just add 0 to the relevance.
    my $select_term = $operator =~ /not/ ? 0 : "($current$rterm1 + $rterm2)";
    $self->COLUMNS->{'relevance'}->{name} = $select_term;
}

sub _long_descs_count {
    my ($self, $args) = @_;
    my ($chart_id, $joins) = @$args{qw(chart_id joins)};
    my $table = "longdescs_count_$chart_id";
    my $extra =  $self->_user->is_insider ? "" : "WHERE isprivate = 0";
    my $join = {
        table => "(SELECT bug_id, COUNT(*) AS num"
                 . " FROM longdescs $extra GROUP BY bug_id)",
        as    => $table,
    };
    push(@$joins, $join);
    $args->{full_field} = "${table}.num";
}

sub _work_time_changedby {
    my ($self, $args) = @_;
    my ($chart_id, $joins, $value) = @$args{qw(chart_id joins value)};
    
    my $table = "longdescs_$chart_id";
    push(@$joins, { table => 'longdescs', as => $table });
    my $user_id = login_to_id($value, THROW_ERROR);
    $args->{term} = "$table.who = $user_id AND $table.work_time != 0";
}

sub _work_time_changedbefore_after {
    my ($self, $args) = @_;
    my ($chart_id, $operator, $value, $joins) =
        @$args{qw(chart_id operator value joins)};
    my $dbh = Bugzilla->dbh;
    
    my $table = "longdescs_$chart_id";
    my $sql_operator = ($operator =~ /before/) ? '<=' : '>=';
    my $sql_date = $dbh->quote(SqlifyDate($value));
    my $join = {
        table => 'longdescs',
        as    => $table,
        extra => ["$table.work_time != 0",
                  "$table.bug_when $sql_operator $sql_date"],
    };
    push(@$joins, $join);
    
    $args->{term} = "$table.bug_when IS NOT NULL";
}

sub _work_time {
    my ($self, $args) = @_;
    $self->_add_extra_column('actual_time');
    $args->{full_field} = $self->COLUMNS->{actual_time}->{name};
}

sub _percentage_complete {
    my ($self, $args) = @_;
    
    $args->{full_field} = $self->COLUMNS->{percentage_complete}->{name};

    # We need actual_time in _select_columns, otherwise we can't use
    # it in the expression for searching percentage_complete.
    $self->_add_extra_column('actual_time');
}

sub _days_elapsed {
    my ($self, $args) = @_;
    my $dbh = Bugzilla->dbh;
    
    $args->{full_field} = "(" . $dbh->sql_to_days('NOW()') . " - " .
                                $dbh->sql_to_days('bugs.delta_ts') . ")";
}

sub _component_nonchanged {
    my ($self, $args) = @_;
    
    $args->{full_field} = "components.name";
    $self->_do_operator_function($args);
    my $term = $args->{term};
    $args->{term} = build_subselect("bugs.component_id",
        "components.id", "components", $args->{term});
}

sub _product_nonchanged {
    my ($self, $args) = @_;
    
    # Generate the restriction condition
    $args->{full_field} = "products.name";
    $self->_do_operator_function($args);
    my $term = $args->{term};
    $args->{term} = build_subselect("bugs.product_id",
        "products.id", "products", $term);
}

sub _classification_nonchanged {
    my ($self, $args) = @_;
    my $joins = $args->{joins};
    
    # This joins the right tables for us.
    $self->_add_extra_column('product');
    
    # Generate the restriction condition    
    $args->{full_field} = "classifications.name";
    $self->_do_operator_function($args);
    my $term = $args->{term};
    $args->{term} = build_subselect("map_product.classification_id",
        "classifications.id", "classifications", $term);
}

sub _nullable {
    my ($self, $args) = @_;
    my $field = $args->{full_field};
    $args->{full_field} = "COALESCE($field, '')";
}

sub _nullable_int {
    my ($self, $args) = @_;
    my $field = $args->{full_field};
    $args->{full_field} = "COALESCE($field, 0)";
}

sub _nullable_datetime {
    my ($self, $args) = @_;
    my $field = $args->{full_field};
    my $empty = Bugzilla->dbh->quote(EMPTY_DATETIME);
    $args->{full_field} = "COALESCE($field, $empty)";
}

sub _deadline {
    my ($self, $args) = @_;
    my $field = $args->{full_field};
    # This makes "equals" searches work on all DBs (even on MySQL, which
    # has a bug: http://bugs.mysql.com/bug.php?id=60324).
    $args->{full_field} = Bugzilla->dbh->sql_date_format($field, '%Y-%m-%d');
    $self->_nullable_datetime($args);
}

sub _owner_idle_time_greater_less {
    my ($self, $args) = @_;
    my ($chart_id, $joins, $value, $operator) =
        @$args{qw(chart_id joins value operator)};
    my $dbh = Bugzilla->dbh;
    
    my $table = "idle_$chart_id";
    my $quoted = $dbh->quote(SqlifyDate($value));
    
    my $ld_table = "comment_$table";
    my $act_table = "activity_$table";    
    my $comments_join = {
        table => 'longdescs',
        as    => $ld_table,
        from  => 'assigned_to',
        to    => 'who',
        extra => ["$ld_table.bug_when > $quoted"],
    };
    my $activity_join = {
        table => 'bugs_activity',
        as    => $act_table,
        from  => 'assigned_to',
        to    => 'who',
        extra => ["$act_table.bug_when > $quoted"]
    };
    
    push(@$joins, $comments_join, $activity_join);
    
    if ($operator =~ /greater/) {
        $args->{term} =
            "$ld_table.who IS NULL AND $act_table.who IS NULL";
    } else {
         $args->{term} =
            "$ld_table.who IS NOT NULL OR $act_table.who IS NOT NULL";
    }
}

sub _multiselect_negative {
    my ($self, $args) = @_;
    my ($field, $operator) = @$args{qw(field operator)};

    $args->{operator} = $self->_reverse_operator($operator);
    $args->{term} = $self->_multiselect_term($args, 1);
}

sub _multiselect_multiple {
    my ($self, $args) = @_;
    my ($chart_id, $field, $operator, $value)
        = @$args{qw(chart_id field operator value)};
    my $dbh = Bugzilla->dbh;
    
    # We want things like "cf_multi_select=two+words" to still be
    # considered a search for two separate words, unless we're using
    # anyexact. (_all_values would consider that to be one "word" with a
    # space in it, because it's not in the Boolean Charts).
    my @words = $operator eq 'anyexact' ? $self->_all_values($args)
                                        : split(/[\s,]+/, $value);
    
    my @terms;
    foreach my $word (@words) {
        next if $word eq '';
        $args->{value} = $word;
        $args->{quoted} = $dbh->quote($word);
        push(@terms, $self->_multiselect_term($args));
    }
    
    # The spacing in the joins helps make the resulting SQL more readable.
    if ($operator =~ /^any/) {
        $args->{term} = join("\n        OR ", @terms);
    }
    else {
        $args->{term} = join("\n        AND ", @terms);
    }
}

sub _multiselect_nonchanged {
    my ($self, $args) = @_;
    my ($chart_id, $joins, $field, $operator) =
        @$args{qw(chart_id joins field operator)};
    $args->{term} = $self->_multiselect_term($args)
}

sub _multiselect_table {
    my ($self, $args) = @_;
    my ($field, $chart_id) = @$args{qw(field chart_id)};
    my $dbh = Bugzilla->dbh;
    
    if ($field eq 'keywords') {
        $args->{full_field} = 'keyworddefs.name';
        return "keywords INNER JOIN keyworddefs".
                               " ON keywords.keywordid = keyworddefs.id";
    }
    elsif ($field eq 'tag') {
        $args->{full_field} = 'tag.name';
        return "bug_tag INNER JOIN tag ON bug_tag.tag_id = tag.id AND user_id = "
               . ($self->_sharer_id || $self->_user->id);
    }
    elsif ($field eq 'bug_group') {
        $args->{full_field} = 'groups.name';
        return "bug_group_map INNER JOIN groups
                                      ON bug_group_map.group_id = groups.id";
    }
    elsif ($field eq 'blocked' or $field eq 'dependson') {
        my $select = $field eq 'blocked' ? 'dependson' : 'blocked';
        $args->{_select_field} = $select;
        $args->{full_field} = $field;
        return "dependencies";
    }
    elsif ($field eq 'longdesc') {
        $args->{_extra_where} = " AND isprivate = 0"
            if !$self->_user->is_insider;
        $args->{full_field} = 'thetext';
        return "longdescs";
    }
    elsif ($field eq 'longdescs.isprivate') {
        ThrowUserError('auth_failure', { action => 'search',
                                         object => 'bug_fields',
                                         field => 'longdescs.isprivate' })
            if !$self->_user->is_insider;
        $args->{full_field} = 'isprivate';
        return "longdescs";
    }
    elsif ($field =~ /^attachments/) {
        $args->{_extra_where} = " AND isprivate = 0"
            if !$self->_user->is_insider;
        $field =~ /^attachments\.(.+)$/;
        $args->{full_field} = $1;
        return "attachments";
    }
    elsif ($field eq 'attach_data.thedata') {
        $args->{_extra_where} = " AND attachments.isprivate = 0"
            if !$self->_user->is_insider;
        return "attachments INNER JOIN attach_data "
               . " ON attachments.attach_id = attach_data.id"
    }
    elsif ($field eq 'flagtypes.name') {
        $args->{full_field} = $dbh->sql_string_concat("flagtypes.name",
                                                      "flags.status");
        return "flags INNER JOIN flagtypes ON flags.type_id = flagtypes.id";
    }
    my $table = "bug_$field";
    $args->{full_field} = "bug_$field.value";
    return $table;
}

sub _multiselect_term {
    my ($self, $args, $not) = @_;
    my $table = $self->_multiselect_table($args);
    $self->_do_operator_function($args);
    my $term = $args->{term};
    $term .= $args->{_extra_where} || '';
    my $select = $args->{_select_field} || 'bug_id';
    my $not_sql = $not ? "NOT " : '';
    return "bugs.bug_id ${not_sql}IN (SELECT $select FROM $table WHERE $term)";
}

###############################
# Standard Operator Functions #
###############################

sub _simple_operator {
    my ($self, $args) = @_;
    my ($full_field, $quoted, $operator) =
        @$args{qw(full_field quoted operator)};
    my $sql_operator = SIMPLE_OPERATORS->{$operator};
    $args->{term} = "$full_field $sql_operator $quoted";
}

sub _casesubstring {
    my ($self, $args) = @_;
    my ($full_field, $quoted) = @$args{qw(full_field quoted)};
    my $dbh = Bugzilla->dbh;
    
    $args->{term} = $dbh->sql_position($quoted, $full_field) . " > 0";
}

sub _substring {
    my ($self, $args) = @_;
    my ($full_field, $quoted) = @$args{qw(full_field quoted)};
    my $dbh = Bugzilla->dbh;
    
    # XXX This should probably be changed to just use LIKE
    $args->{term} = $dbh->sql_iposition($quoted, $full_field) . " > 0";
}

sub _notsubstring {
    my ($self, $args) = @_;
    my ($full_field, $quoted) = @$args{qw(full_field quoted)};
    my $dbh = Bugzilla->dbh;
    
    # XXX This should probably be changed to just use NOT LIKE
    $args->{term} = $dbh->sql_iposition($quoted, $full_field) . " = 0";
}

sub _regexp {
    my ($self, $args) = @_;
    my ($full_field, $quoted) = @$args{qw(full_field quoted)};
    my $dbh = Bugzilla->dbh;
    
    $args->{term} = $dbh->sql_regexp($full_field, $quoted);
}

sub _notregexp {
    my ($self, $args) = @_;
    my ($full_field, $quoted) = @$args{qw(full_field quoted)};
    my $dbh = Bugzilla->dbh;
    
    $args->{term} = $dbh->sql_not_regexp($full_field, $quoted);
}

sub _anyexact {
    my ($self, $args) = @_;
    my ($field, $full_field) = @$args{qw(field full_field)};
    my $dbh = Bugzilla->dbh;
    
    my @list = $self->_all_values($args, ',');
    @list = map { $self->_quote_unless_numeric($args, $_) } @list;
    
    if (@list) {
        $args->{term} = $dbh->sql_in($full_field, \@list);
    }
    else {
        $args->{term} = '';
    }
}

sub _anywordsubstr {
    my ($self, $args) = @_;

    my @terms = $self->_substring_terms($args);
    $args->{term} = join("\n\tOR ", @terms);
}

sub _allwordssubstr {
    my ($self, $args) = @_;

    my @terms = $self->_substring_terms($args);
    $args->{term} = join("\n\tAND ", @terms);
}

sub _nowordssubstr {
    my ($self, $args) = @_;
    $self->_anywordsubstr($args);
    my $term = $args->{term};
    $args->{term} = "NOT($term)";
}

sub _anywords {
    my ($self, $args) = @_;
    
    my @terms = $self->_word_terms($args);
    # Because _word_terms uses AND, we need to parenthesize its terms
    # if there are more than one.
    @terms = map("($_)", @terms) if scalar(@terms) > 1;
    $args->{term} = join("\n\tOR ", @terms);
}

sub _allwords {
    my ($self, $args) = @_;
    
    my @terms = $self->_word_terms($args);
    $args->{term} = join("\n\tAND ", @terms);
}

sub _nowords {
    my ($self, $args) = @_;
    $self->_anywords($args);
    my $term = $args->{term};
    $args->{term} = "NOT($term)";
}

sub _changedbefore_changedafter {
    my ($self, $args) = @_;
    my ($chart_id, $joins, $field, $operator, $value) =
        @$args{qw(chart_id joins field operator value)};
    my $dbh = Bugzilla->dbh;

    my $field_object = $self->_chart_fields->{$field}
        || ThrowCodeError("invalid_field_name", { field => $field });
    
    # Asking when creation_ts changed is just asking when the bug was created.
    if ($field_object->name eq 'creation_ts') {
        $args->{operator} =
            $operator eq 'changedbefore' ? 'lessthaneq' : 'greaterthaneq';
        return $self->_do_operator_function($args);
    }
    
    my $sql_operator = ($operator =~ /before/) ? '<=' : '>=';
    my $field_id = $field_object->id;
    # Charts on changed* fields need to be field-specific. Otherwise,
    # OR chart rows make no sense if they contain multiple fields.
    my $table = "act_${field_id}_$chart_id";

    my $sql_date = $dbh->quote(SqlifyDate($value));
    my $join = {
        table => 'bugs_activity',
        as    => $table,
        extra => ["$table.fieldid = $field_id",
                  "$table.bug_when $sql_operator $sql_date"],
    };

    $args->{term} = "$table.bug_when IS NOT NULL";
    $self->_changed_security_check($args, $join);
    push(@$joins, $join);
}

sub _changedfrom_changedto {
    my ($self, $args) = @_;
    my ($chart_id, $joins, $field, $operator, $quoted) =
        @$args{qw(chart_id joins field operator quoted)};
    
    my $column = ($operator =~ /from/) ? 'removed' : 'added';
    my $field_object = $self->_chart_fields->{$field}
        || ThrowCodeError("invalid_field_name", { field => $field });
    my $field_id = $field_object->id;
    my $table = "act_${field_id}_$chart_id";
    my $join = {
        table => 'bugs_activity',
        as    => $table,
        extra => ["$table.fieldid = $field_id",
                  "$table.$column = $quoted"],
    };

    $args->{term} = "$table.bug_when IS NOT NULL";
    $self->_changed_security_check($args, $join);
    push(@$joins, $join);
}

sub _changedby {
    my ($self, $args) = @_;
    my ($chart_id, $joins, $field, $operator, $value) =
        @$args{qw(chart_id joins field operator value)};
    
    my $field_object = $self->_chart_fields->{$field}
        || ThrowCodeError("invalid_field_name", { field => $field });
    my $field_id = $field_object->id;
    my $table = "act_${field_id}_$chart_id";
    my $user_id  = login_to_id($value, THROW_ERROR);
    my $join = {
        table => 'bugs_activity',
        as    => $table,
        extra => ["$table.fieldid = $field_id",
                  "$table.who = $user_id"],
    };

    $args->{term} = "$table.bug_when IS NOT NULL";
    $self->_changed_security_check($args, $join);
    push(@$joins, $join);
}

sub _changed_security_check {
    my ($self, $args, $join) = @_;
    my ($chart_id, $field) = @$args{qw(chart_id field)};

    my $field_object = $self->_chart_fields->{$field}
        || ThrowCodeError("invalid_field_name", { field => $field });
    my $field_id = $field_object->id;

    # If the user is not part of the insiders group, they cannot see
    # changes to attachments (including attachment flags) that are private
    if ($field =~ /^(?:flagtypes\.name$|attach)/ and !$self->_user->is_insider) {
        $join->{then_to} = {
            as    => "attach_${field_id}_$chart_id",
            table => 'attachments',
            from  => "act_${field_id}_$chart_id.attach_id",
            to    => 'attach_id',
        };

        $args->{term} .= " AND COALESCE(attach_${field_id}_$chart_id.isprivate, 0) = 0";
    }
}

######################
# Public Subroutines #
######################

# Validate that the query type is one we can deal with
sub IsValidQueryType
{
    my ($queryType) = @_;
    if (grep { $_ eq $queryType } qw(specific advanced)) {
        return 1;
    }
    return 0;
}

# Splits out "asc|desc" from a sort order item.
sub split_order_term {
    my $fragment = shift;
    $fragment =~ /^(.+?)(?:\s+(ASC|DESC))?$/i;
    my ($column_name, $direction) = (lc($1), uc($2 || ''));
    return wantarray ? ($column_name, $direction) : $column_name;
}

# Used to translate old SQL fragments from buglist.cgi's "order" argument
# into our modern field IDs.
sub translate_old_column {
    my ($column) = @_;
    # All old SQL fragments have a period in them somewhere.
    return $column if $column !~ /\./;

    if ($column =~ /\bAS\s+(\w+)$/i) {
        return $1;
    }
    # product, component, classification, assigned_to, qa_contact, reporter
    elsif ($column =~ /map_(\w+?)s?\.(login_)?name/i) {
        return $1;
    }
    
    # If it doesn't match the regexps above, check to see if the old 
    # SQL fragment matches the SQL of an existing column
    foreach my $key (%{ COLUMNS() }) {
        next unless exists COLUMNS->{$key}->{name};
        return $key if COLUMNS->{$key}->{name} eq $column;
    }

    return $column;
}

1;