summaryrefslogtreecommitdiffstats
path: root/includes/view.inc
blob: bd2dc58fb805fbf9668fdb90f8a807db3284cc31 (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
<?php
/**
 * @file view.inc
 * Provides the view object type and associated methods.
 */

/**
 * @defgroup views_objects Objects that represent a View or part of a view.
 * @{
 * These objects are the core of Views do the bulk of the direction and
 * storing of data. All database activity is in these objects.
 */

/**
 * An object to contain all of the data to generate a view, plus the member
 * functions to build the view query, execute the query and render the output.
 */
class view extends views_db_object {
  var $db_table = 'views_view';
  var $base_table = 'node';

  // State variables
  var $built = FALSE;
  var $executed = FALSE;

  var $args = array();
  var $build_info = array();

  var $use_ajax = FALSE;

  // Where the results of a query will go.
  var $result = array();

  // pager variables
  var $pager = array(
    'use_pager' => FALSE,
    'items_per_page' => 10,
    'element' => 0,
    'offset' => 0,
    'current_page' => 0,
  );

  // Places to put attached renderings:
  var $attachment_before = '';
  var $attachment_after = '';

  // Exposed widget input
  var $exposed_data = array();
  var $exposed_input = array();

  // Used to store views that were previously running if we recurse.
  var $old_view = array();

  /**
   * Identifier of the current display.
   *
   * @var string
   */
  var $current_display;
  
  /**
   * Constructor
   */
  function view() {
    parent::init();
    // Make sure all of our sub objects are arrays.
    foreach ($this->db_objects() as $object) {
      $this->$object = array();
    }

    $this->query = new stdClass();
  }

  /**
   * Returns a list of the sub-object types used by this view. These types are
   * stored on the display, and are used in the build process.
   */
  function display_objects() {
    return array('argument', 'field', 'sort', 'filter', 'relationship');
  }

  /**
   * Returns the complete list of dependent objects in a view, for the purpose
   * of initialization and loading/saving to/from the database.
   *
   * Note: In PHP5 this should be static, but PHP4 doesn't support static
   * methods.
   */
  function db_objects() {
    return array('display');
  }

  /**
   * Set the arguments that come to this view. Usually from the URL
   * but possibly from elsewhere.
   */
  function set_arguments($args) {
    $this->args = $args;
  }

  /**
   * Set the page size for ranged or pager queries
   */
  function set_items_per_page($items_per_page) {
    $this->pager['items_per_page'] = $items_per_page;
    if (empty($items_per_page)) {
      $this->pager['use_pager'] = FALSE;
    }
  }

  /**
   * Change/Set the current page for the pager.
   */
  function set_current_page($page) {
    $this->pager['current_page'] = $page;
  }

  /**
   * Whether or not the pager should be used.
   */
  function set_use_pager($use_pager) {
    $this->pager['use_pager'] = $use_pager;
  }

  /**
   * The pager element id to use if use_apger is on
   */
  function set_pager_element($pager_element) {
    $this->pager['element'] = $pager_element;
  }

  /**
   * Synchronize views pager with global pager variables
   *
   */
  function synchronize_pager() {
    if (!empty($this->pager['use_pager'])) {
    // dump information about what we already know into the globals
      global $pager_page_array, $pager_total, $pager_total_items;
      // total rows in query
      $pager_total_items[$this->pager['element']] = $this->total_rows;
      // total pages
      $pager_total[$this->pager['element']] = ceil($pager_total_items[$this->pager['element']] / $this->pager['items_per_page']);

      // What page was requested:
      $pager_page_array = isset($_GET['page']) ? explode(',', $_GET['page']) : array();

      // If the requested page was within range. $this->pager['current_page']
      // defaults to 0 so we don't need to set it in an out-of-range condition.
      if (!empty($pager_page_array[$this->pager['element']])) {
        $page = intval($pager_page_array[$this->pager['element']]);
        if ($page > 0 && $page < $pager_total[$this->pager['element']]) {
          $this->pager['current_page'] = $page;
        }
      }
      $pager_page_array[$this->pager['element']] = $this->pager['current_page'];
    }
  }

  /**
   * How many records to skip. This does not function if use_pager is
   * set.
   */
  function set_offset($offset) {
    $this->pager['offset'] = $offset;
  }

  /**
   * Whether or not AJAX should be used. If AJAX is used, paging,
   * tablesorting and exposed filters will be fetched via an AJAX call
   * rather than a page refresh.
   */
  function set_use_ajax($use_ajax) {
    $this->use_ajax = $use_ajax;
  }

  /**
   * Set the exposed filters input to an array. If unset they will be taken
   * from $_GET when the time comes.
   */
  function set_exposed_input($filters) {
    $this->exposed_input = $filters;
  }

  /**
   * Figure out what the exposed input for this view is.
   */
  function get_exposed_input() {
    // Fill our input either from $_GET or from something previously set on the
    // view.
    if (empty($this->exposed_input)) {
      $this->exposed_input = $_GET;
      // unset items that are definitely not our input:
      foreach (array('page', 'q') as $key) {
        if (isset($this->exposed_input[$key])) {
          unset($this->exposed_input[$key]);
        }
      }

      // If we have no input at all, check for remembered input via session.

      // If filters are not overridden, store the 'remember' settings on the
      // default display. If they are, store them on this display. This way,
      // multiple displays in the same view can share the same filters and
      // remember settings.
      $display_id = ($this->display_handler->is_defaulted('filters')) ? 'default' : $this->current_display;

      if (empty($this->exposed_input) && !empty($_SESSION['views'][$this->name][$display_id])) {
        $this->exposed_input = $_SESSION['views'][$this->name][$display_id];
      }
    }

    return $this->exposed_input;
  }

  /**
   * Set the display for this view and initialize the display handler.
   */
  function init_display($reset = FALSE) {
    // The default display is always the first one in the list.
    if (isset($this->current_display)) {
      return TRUE;
    }

    // Instantiate all displays
    foreach (array_keys($this->display) as $id) {
      // Correct for shallow cloning
      // Often we'll have a cloned view so we don't mess up each other's
      // displays, but the clone is pretty shallow and doesn't necessarily
      // clone the displays. We can tell this by looking to see if a handler
      // has already been set; if it has, but $this->current_display is not
      // set, then something is dreadfully wrong.
      if (!empty($this->display[$id]->handler)) {
        $this->display[$id] = drupal_clone($this->display[$id]);
        unset($this->display[$id]->handler);
      }
      $this->display[$id]->handler = views_get_plugin('display', $this->display[$id]->display_plugin);
      if (!empty($this->display[$id]->handler)) {
        // Initialize the new display handler with data.
        $this->display[$id]->handler->init($this, $this->display[$id]);
        // If this is NOT the default display handler, let it know which is
        // since it may well utilize some data from the default.
        // This assumes that the 'default' handler is always first. It always
        // is. Make sure of it.
        if ($id != 'default') {
          $this->display[$id]->handler->default_display = &$this->display['default']->handler;
        }
      }
    }

    $this->current_display = 'default';
    $this->display_handler = &$this->display['default']->handler;

    return TRUE;
  }

  /**
   * Get the first display that is accessible to the user.
   *
   * @param $displays
   *   Either a single display id or an array of display ids.
   */
  function choose_display($displays) {
    if (!is_array($displays)) {
      return $displays;
    }

    $this->init_display();

    foreach ($displays as $display_id) {
      if ($this->display[$display_id]->handler->access()) {
        return $display_id;
      }
    }

    return 'default';
  }

  /**
   * Set the display as current.
   *
   * @param $display_id
   *   The id of the display to mark as current.
   */
  function set_display($display_id = NULL) {
    // If we have not already initialized the display, do so. But be careful.
    if (empty($this->current_display)) {
      $this->init_display();

      // If handlers were not initialized, and no argument was sent, set up
      // to the default display.
      if (empty($display_id)) {
        $display_id = 'default';
      }
    }

    $display_id = $this->choose_display($display_id);

    // If no display id sent in and one wasn't chosen above, we're finished.
    if (empty($display_id)) {
      return FALSE;
    }

    // Ensure the requested display exists.
    if (empty($this->display[$display_id])) {
      $display_id = 'default';
      if (empty($this->display[$display_id])) {
        vpr(t('set_display() called with invalid display id @display.', array('@display' => $display_id)));
        return FALSE;
      }
    }

    // Set the current display.
    $this->current_display = $display_id;

    // Ensure requested display has a working handler.
    if (empty($this->display[$display_id]->handler)) {
      return FALSE;
    }

    // Set a shortcut
    $this->display_handler = &$this->display[$display_id]->handler;

    return TRUE;
  }

  /**
   * Find and initialize the style plugin.
   *
   * Note that arguments may have changed which style plugin we use, so
   * check the view object first, then ask the display handler.
   */
  function init_style() {
    if (isset($this->style_plugin)) {
      return is_object($this->style_plugin);
    }

    if (!isset($this->plugin_name)) {
      $this->plugin_name = $this->display_handler->get_option('style_plugin');
      $this->style_options = $this->display_handler->get_option('style_options');
    }

    $this->style_plugin = views_get_plugin('style', $this->plugin_name);

    if (empty($this->style_plugin)) {
      return FALSE;
    }

    // init the new style handler with data.
    $this->style_plugin->init($this, $this->display[$this->current_display], $this->style_options);
    return TRUE;
  }

  /**
   * Acquire and attach all of the handlers.
   */
  function init_handlers() {
    if (empty($this->inited)) {
      foreach (views_object_types() as $key => $info) {
        $this->_init_handler($key, $info);
      }
      $this->inited = TRUE;
    }
  }

  /**
   * Create a list of base tables eligible for this view. Used primarily
   * for the UI. Display must be already initialized.
   */
  function get_base_tables() {
    $base_tables = array(
      $this->base_table => TRUE,
      '#global' => TRUE,
    );

    foreach ($this->display_handler->get_handlers('relationship') as $handler) {
      $base_tables[$handler->definition['base']] = TRUE;
    }
    return $base_tables;
  }

  /**
   * Run the pre_query() on all active handlers.
   */
  function _pre_query() {
    foreach (views_object_types() as $key => $info) {
      $handlers = &$this->$key;
      $position = 0;
      foreach ($handlers as $id => $handler) {
        $handlers[$id]->position = $position;
        $handlers[$id]->pre_query();
        $position++;
      }
    }
  }

  /**
   * Attach all of the handlers for each type.
   *
   * @param $key
   *   One of 'argument', 'field', 'sort', 'filter', 'relationship'
   * @param $info
   *   The $info from views_object_types for this object.
   */
  function _init_handler($key, $info) {
    // Load the requested items from the display onto the object.
    $this->$key = $this->display_handler->get_handlers($key);

    // This reference deals with difficult PHP indirection.
    $handlers = &$this->$key;

    // Run through and test for accessibility.
    foreach ($handlers as $id => $handler) {
      if (!$handler->access()) {
        unset($handlers[$id]);
      }
    }
  }

  /**
   * Render the exposed filter form.
   *
   * This actually does more than that; because it's using FAPI, the form will
   * also assign data to the appropriate handlers for use in building the
   * query.
   */
  function render_exposed_form($block = FALSE) {
    // Deal with any exposed filters we may have, before building.
    $form_state = array(
      'view' => &$this,
      'display' => &$this->display_handler->display,
      'method' => 'get',
      'rerender' => TRUE,
      'no_redirect' => TRUE,
    );

    // Some types of displays (eg. attachments) may wish to use the exposed
    // filters of their parent displays instead of showing an additional
    // exposed filter form for the attachment as well as that for the parent.
    if (!$this->display_handler->displays_exposed() || (!$block && $this->display_handler->get_option('exposed_block'))) {
      unset($form_state['rerender']);
    }

    if (!empty($this->ajax)) {
      $form_state['ajax'] = TRUE;
    }

    $output = drupal_build_form('views_exposed_form', $form_state);
    if (!empty($form_state['js settings'])) {
      $this->js_settings = $form_state['js settings'];
    }

    // Don't render exposed filter form when there's form errors.
    // Applies when filters are in a block ("exposed_block" option).
    if (form_get_errors() && empty($form_state['rerender'])) {
      return NULL;
    }

    return $output;
  }

  /**
   * Build all the arguments.
   */
  function _build_arguments() {
    // Initially, we want to build sorts and fields. This can change, though,
    // if we get a summary view.
    if (empty($this->argument)) {
      return TRUE;
    }

    // build arguments.
    $position = -1;

    // Create a title for use in the breadcrumb trail.
    $title = $this->display_handler->get_option('title');

    $this->build_info['breadcrumb'] = array();
    $breadcrumb_args = array();
    $substitutions = array();

    $status = TRUE;

    // Iterate through each argument and process.
    foreach ($this->argument as $id => $arg) {
      $position++;
      $argument = &$this->argument[$id];

      if ($argument->broken()) {
        continue;
      }

      $argument->set_relationship();

      $arg = isset($this->args[$position]) ? $this->args[$position] : NULL;
      $argument->position = $position;

      if (isset($arg) || $argument->has_default_argument()) {
        if (!isset($arg)) {
          $arg = $argument->get_default_argument();
          // make sure default args get put back.
          if (isset($arg)) {
            $this->args[$position] = $arg;
          }
        }

        // Set the argument, which will also validate that the argument can be set.
        if (!$argument->set_argument($arg)) {
          $status = $argument->validate_fail($arg);
          break;
        }

        if ($argument->is_wildcard()) {
          $arg_title = $argument->wildcard_title();
        }
        else {
          $arg_title = $argument->get_title();
          $argument->query();
        }

        // Add this argument's substitution
        $substitutions['%' . ($position + 1)] = $arg_title;

        // Since we're really generating the breadcrumb for the item above us,
        // check the default action of this argument.
        if ($this->display_handler->uses_breadcrumb() && $argument->uses_breadcrumb()) {
          $path = $this->get_url($breadcrumb_args);
          if (strpos($path, '%') === FALSE) {
            $breadcrumb = !empty($argument->options['breadcrumb'])? $argument->options['breadcrumb'] : $title;
            $this->build_info['breadcrumb'][$path] = str_replace(array_keys($substitutions), $substitutions, $breadcrumb);
          }
        }

        // Allow the argument to muck with this breadcrumb.
        $argument->set_breadcrumb($this->build_info['breadcrumb']);

        // Test to see if we should use this argument's title
        if (!empty($argument->options['title'])) {
          $title = $argument->options['title'];
        }

        $breadcrumb_args[] = $arg;
      }
      else {
        // determine default condition and handle.
        $status = $argument->default_action();
        break;
      }

      // Be safe with references and loops:
      unset($argument);
    }

    // set the title in the build info.
    if (!empty($title)) {
      $this->build_info['title'] = str_replace(array_keys($substitutions), $substitutions, $title);
    }

    // Store the arguments for later use.
    $this->build_info['substitutions'] = $substitutions;

    return $status;
  }

  /**
   * Do some common building initialization.
   */
  function init_query() {
    // Create and initialize the query object.
    $views_data = views_fetch_data($this->base_table);
    $this->base_field = $views_data['table']['base']['field'];
    if (!empty($views_data['table']['base']['database'])) {
      $this->base_database = $views_data['table']['base']['database'];
    }
    views_include('query');
    $this->query = new views_query($this->base_table, $this->base_field);
  }

  /**
   * Build the query for the view.
   */
  function build($display_id = NULL) {
    if (!empty($this->built)) {
      return;
    }

    if (empty($this->current_display) || $display_id) {
      if (!$this->set_display($display_id)) {
        return FALSE;
      }
    }

    // Let modules modify the view just prior to building it.
    foreach (module_implements('views_pre_build') as $module) {
      $function = $module . '_views_pre_build';
      $function($this);
    }

    // Attempt to load from cache.
    // @todo Load a build_info from cache.

    $start = views_microtime();
    // If that fails, let's build!
    $this->build_info = array(
      'query' => '',
      'count_query' => '',
      'query_args' => array(),
    );

    $this->init_query();

    // Call a module hook and see if it wants to present us with a
    // pre-built query or instruct us not to build the query for
    // some reason.
    // @todo: Implement this. Use the same mechanism Panels uses.

    // Run through our handlers and ensure they have necessary information.
    $this->init_handlers();

    // Let the handlers interact with each other if they really want.
    $this->_pre_query();

    if ($this->display_handler->uses_exposed()) {
      $this->exposed_widgets = $this->render_exposed_form();
      if (form_set_error() || !empty($this->build_info['abort'])) {
        $this->built = TRUE;
        // Don't execute the query, but rendering will still be executed to display the empty text.
        $this->executed = TRUE;
        return empty($this->build_info['fail']);
      }
    }

    // Build all the relationships first thing.
    $this->_build('relationship');

    // Build all the filters.
    $this->_build('filter');

    $this->build_sort = TRUE;

    // Arguments can, in fact, cause this whole thing to abort.
    if (!$this->_build_arguments()) {
      $this->build_time = views_microtime() - $start;
      $this->attach_displays();
      return $this->built;
    }

    // Initialize the style; arguments may have changed which style we use,
    // so waiting as long as possible is important. But we need to know
    // about the style when we go to build fields.
    if (!$this->init_style()) {
      $this->build_info['fail'] = TRUE;
      return FALSE;
    }

    if ($this->style_plugin->uses_fields()) {
      $this->_build('field');
    }

    // Build our sort criteria if we were instructed to do so.
    if (!empty($this->build_sort)) {
      // Allow the style handler to deal with sorting.
      if ($this->style_plugin->build_sort()) {
        $this->_build('sort');
      }
      // allow the plugin to build second sorts as well.
      $this->style_plugin->build_sort_post();
    }

    // Allow display handler to affect the query:
    $this->display_handler->query();

    // Allow style handler to affect the query:
    $this->style_plugin->query();

    if (variable_get('views_sql_signature', FALSE)) {
      $this->query->add_field(NULL, "'" . $this->name . ':' . $this->current_display . "'", 'view_name');
    }

    // Let modules modify the query just prior to finalizing it.
    foreach (module_implements('views_query_alter') as $module) {
      $function = $module . '_views_query_alter';
      $function($this, $this->query);
    }

    $this->build_info['query'] = $this->query->query();
    $this->build_info['count_query'] = $this->query->query(TRUE);
    $this->build_info['query_args'] = $this->query->get_where_args();
    $this->built = TRUE;
    $this->build_time = views_microtime() - $start;

    // Attach displays
    $this->attach_displays();

    // Let modules modify the view just after building it.
    foreach (module_implements('views_post_build') as $module) {
      $function = $module . '_views_post_build';
      $function($this);
    }

    return TRUE;
  }

  /**
   * Internal method to build an individual set of handlers.
   */
  function _build($key) {
    $handlers = &$this->$key;
    foreach ($handlers as $id => $data) {
      if (!empty($handlers[$id]) && is_object($handlers[$id])) {
        // Give this handler access to the exposed filter input.
        if (!empty($this->exposed_data)) {
          $rc = $handlers[$id]->accept_exposed_input($this->exposed_data);
          $handlers[$id]->store_exposed_input($this->exposed_data, $rc);
          if (!$rc) {
            continue;
          }
        }
        $handlers[$id]->set_relationship();
        $handlers[$id]->query();
      }
    }
  }

  /**
   * Execute the view's query.
   */
  function execute($display_id = NULL) {
    if (empty($this->built)) {
      if (!$this->build($display_id)) {
        return FALSE;
      }
    }

    if (!empty($this->executed)) {
      return TRUE;
    }

    // Let modules modify the view just prior to executing it.
    foreach (module_implements('views_pre_execute') as $module) {
      $function = $module . '_views_pre_execute';
      $function($this);
    }

    $query = db_rewrite_sql($this->build_info['query'], $this->base_table, $this->base_field, array('view' => &$this));
    $count_query = db_rewrite_sql($this->build_info['count_query'], $this->base_table, $this->base_field, array('view' => &$this));

    $args = $this->build_info['query_args'];

    vpr($query);


    // Check for already-cached results.
    if (!empty($this->live_preview)) {
      $cache = FALSE;
    }
    else {
      $cache = $this->display_handler->get_cache_plugin();
    }
    if ($cache && $cache->cache_get('results')) {
      $this->synchronize_pager();
      vpr('Used cached results');
    }
    else {
      $items = array();
      if ($query) {
        $replacements = module_invoke_all('views_query_substitutions', $this);
        $query = str_replace(array_keys($replacements), $replacements, $query);
        $count_query = 'SELECT COUNT(*) FROM (' . str_replace(array_keys($replacements), $replacements, $count_query) . ') count_alias';

        if (is_array($args)) {
          foreach ($args as $id => $arg) {
            $args[$id] = str_replace(array_keys($replacements), $replacements, $arg);
          }
        }

        // Allow for a view to query an external database.
        if (isset($this->base_database)) {
          db_set_active($this->base_database);
          $external = TRUE;
        }

        $start = views_microtime();
        if (!empty($this->pager['items_per_page'])) {
          // We no longer use pager_query() here because pager_query() does not
          // support an offset. This is fine as we don't actually need pager
          // query; we've already been doing most of what it does, and we
          // just need to do a little more playing with globals.
          if (!empty($this->pager['use_pager']) || !empty($this->get_total_rows)) {
            $this->total_rows = db_result(db_query($count_query, $args)) - $this->pager['offset'];
          }

          $this->synchronize_pager();
          $offset = $this->pager['current_page'] * $this->pager['items_per_page'] + $this->pager['offset'];
          $result = db_query_range($query, $args, $offset, $this->pager['items_per_page']);

        }
        else {
          $result = db_query($query, $args);
        }

        $this->result = array();
        while ($item = db_fetch_object($result)) {
          $this->result[] = $item;
        }

        // If we already know how many items we have even if we did not run the
        // count query, go ahead and set that value:
        if (empty($this->pager['items_per_page'])) {
          $this->total_rows = count($this->result);
        }

        if (!empty($external)) {
          db_set_active();
        }
        $this->execute_time = views_microtime() - $start;
      }
      if ($cache) {
        $cache->cache_set('results');
      }
    }

    // Let modules modify the view just after executing it.
    foreach (module_implements('views_post_execute') as $module) {
      $function = $module . '_views_post_execute';
      $function($this);
    }

    $this->executed = TRUE;
  }

  /**
   * Render this view for display.
   */
  function render($display_id = NULL) {
    $this->execute($display_id);

    // Check to see if the build failed.
    if (!empty($this->build_info['fail'])) {
      return;
    }

    init_theme();

    $start = views_microtime();
    if (!empty($this->live_preview) && variable_get('views_show_additional_queries', FALSE)) {
      $this->start_query_capture();
    }

    // Check for already-cached output.
    if (!empty($this->live_preview)) {
      $cache = FALSE;
    }
    else {
      $cache = $this->display_handler->get_cache_plugin();
    }
    if ($cache && $cache->cache_get('output')) {
      vpr('Used cached output');
    }
    else {
      if ($cache) {
        $cache->cache_start();
      }

      // Initialize the style plugin.
      $this->init_style();

      $this->style_plugin->pre_render($this->result);

      // Let modules modify the view just prior to rendering it.
      foreach (module_implements('views_pre_render') as $module) {
        $function = $module . '_views_pre_render';
        $function($this);
      }

      // Let the theme play too, because pre render is a very themey thing.
      $function = $GLOBALS['theme'] . '_views_pre_render';
      if (function_exists($function)) {
        $function($this, $this->display_handler->output, $cache);
      }

      // Give field handlers the opportunity to perform additional queries
      // using the entire resultset prior to rendering.
      if ($this->style_plugin->uses_fields()) {
        foreach ($this->field as $id => $handler) {
          if (!empty($this->field[$id])) {
            $this->field[$id]->pre_render($this->result);
          }
        }
      }
      $this->display_handler->output = $this->display_handler->render();
      if ($cache) {
        $cache->cache_set('output');
      }
    }

    if ($cache) {
      $cache->post_render($this->display_handler->output);
    }

    // Let modules modify the view output after it is rendered.
    foreach (module_implements('views_post_render') as $module) {
      $function = $module . '_views_post_render';
      $function($this, $this->display_handler->output, $cache);
    }

    // Let the theme play too, because post render is a very themey thing.
    $function = $GLOBALS['theme'] . '_views_post_render';
    if (function_exists($function)) {
      $function($this, $this->display_handler->output, $cache);
    }

    if (!empty($this->live_preview) && variable_get('views_show_additional_queries', FALSE)) {
      $this->end_query_capture();
    }
    $this->render_time = views_microtime() - $start;

    return $this->display_handler->output;
  }

  /**
   * Render a specific field via the field ID and the row #.
   */
  function render_field($field, $row) {
    if (isset($this->field[$field]) && isset($this->result[$row])) {
      return $this->field[$field]->advanced_render($this->result[$row]);
    }
  }

  /**
   * Execute the given display, with the given arguments.
   * To be called externally by whatever mechanism invokes the view,
   * such as a page callback, hook_block, etc.
   *
   * This function should NOT be used by anything external as this
   * returns data in the format specified by the display. It can also
   * have other side effects that are only intended for the 'proper'
   * use of the display, such as setting page titles and breadcrumbs.
   *
   * If you simply want to view the display, use view::preview() instead.
   */
  function execute_display($display_id = NULL, $args = array()) {
    if (empty($this->current_display) || $this->current_display != $this->choose_display($display_id)) {
      if (!$this->set_display($display_id)) {
        return FALSE;
      }
    }

    $this->pre_execute($args);

    // Execute the view
    $output = $this->display_handler->execute();

    $this->post_execute();
    return $output;
  }

  /**
   * Preview the given display, with the given arguments.
   *
   * To be called externally, probably by an AJAX handler of some flavor.
   * Can also be called when views are embedded, as this guarantees
   * normalized output.
   */
  function preview($display_id = NULL, $args = array()) {
    if (empty($this->current_display) || ((!empty($display_id)) && $this->current_display != $display_id)) {
      if (!$this->set_display($display_id)) {
        return FALSE;
      }
    }

    $this->preview = TRUE;
    $this->pre_execute($args);
    // Preview the view.
    $output = $this->display_handler->preview();

    $this->post_execute();
    return $output;
  }

  /**
   * Run attachments and let the display do what it needs to do prior
   * to running.
   */
  function pre_execute($args = array()) {
    $this->old_view[] = views_get_current_view();
    views_set_current_view($this);
    $display_id = $this->current_display;

    // Let modules modify the view just prior to executing it.
    foreach (module_implements('views_pre_view') as $module) {
      $function = $module . '_views_pre_view';
      $function($this, $display_id, $args);
    }

    // Prepare the view with the information we have, but only if we were
    // passed arguments, as they may have been set previously.
    if ($args) {
      $this->set_arguments($args);
    }

//    $this->attach_displays();

    // Allow the display handler to set up for execution
    $this->display_handler->pre_execute();
  }

  /**
   * Unset the current view, mostly.
   */
  function post_execute() {
    // unset current view so we can be properly destructed later on.
    // Return the previous value in case we're an attachment.

    if ($this->old_view) {
      $old_view = array_pop($this->old_view);
    }

    views_set_current_view(isset($old_view) ? $old_view : FALSE);
  }

  /**
   * Run attachment displays for the view.
   */
  function attach_displays() {
    if (!empty($this->is_attachment)) {
      return;
    }

    if (!$this->display_handler->accept_attachments()) {
      return;
    }

    $this->is_attachment = TRUE;
    // Give other displays an opportunity to attach to the view.
    foreach ($this->display as $id => $display) {
      if (!empty($this->display[$id]->handler)) {
        $this->display[$id]->handler->attach_to($this->current_display);
      }
    }
    $this->is_attachment = FALSE;
  }

  /**
   * Called to get hook_menu() information from the view and the named display handler.
   *
   * @param $display_id
   *   A display id.
   * @param $callbacks
   *   A menu callback array passed from views_menu_alter().
   */
  function execute_hook_menu($display_id = NULL, $callbacks = array()) {
    // Prepare the view with the information we have.

    // This was probably already called, but it's good to be safe.
    if (!$this->set_display($display_id)) {
      return FALSE;
    }

    // Execute the view
    if (isset($this->display_handler)) {
      return $this->display_handler->execute_hook_menu($callbacks);
    }
  }

  /**
   * Called to get hook_block information from the view and the
   * named display handler.
   */
  function execute_hook_block($display_id = NULL) {
    // Prepare the view with the information we have.

    // This was probably already called, but it's good to be safe.
    if (!$this->set_display($display_id)) {
      return FALSE;
    }

    // Execute the view
    if (isset($this->display_handler)) {
      return $this->display_handler->execute_hook_block();
    }
  }

  /**
   * Determine if the given user has access to the view. Note that
   * this sets the display handler if it hasn't been.
   */
  function access($displays = NULL, $account = NULL) {
    // Noone should have access to disabled views.
    if (!empty($this->disabled)) {
      return FALSE;
    }

    if (!isset($this->current_display)) {
      $this->init_display();
    }

    if (!$account) {
      $account = $GLOBALS['user'];
    }

    // We can't use choose_display() here because that function
    // calls this one.
    $displays = (array)$displays;
    foreach ($displays as $display_id) {
      if (!empty($this->display[$display_id]->handler)) {
        if ($this->display[$display_id]->handler->access($account)) {
          return TRUE;
        }
      }
    }

    return FALSE;
  }

  /**
   * Get the view's current title. This can change depending upon how it
   * was built.
   */
  function get_title() {
    if (empty($this->display_handler)) {
      if (!$this->set_display('default')) {
        return FALSE;
      }
    }

    // During building, we might find a title override. If so, use it.
    if (!empty($this->build_info['title'])) {
      $title = $this->build_info['title'];
    }
    else {
      $title = $this->display_handler->get_option('title');
    }

    return $title;
  }

  /**
   * Force the view to build a title.
   */
  function build_title() {
    $this->init_display();
    if (empty($this->built)) {
      $this->init_query();
    }
    $this->init_handlers();

    $this->_build_arguments();
  }

  /**
   * Get the URL for the current view.
   *
   * This URL will be adjusted for arguments.
   */
  function get_url($args = NULL, $path = NULL) {
    if (!isset($path)) {
      $path = $this->get_path();
    }
    if (!isset($args)) {
      $args = $this->args;
    }
    // Don't bother working if there's nothing to do:
    if (empty($path) || (empty($args) && strpos($path, '%') === FALSE)) {
      return $path;
    }

    $pieces = array();
    $arguments = isset($arguments) ? $arguments : $this->display_handler->get_option('arguments');
    $argument_keys = isset($arguments) ? array_keys($arguments) : array();
    $id = current($argument_keys);
    foreach (explode('/', $path) as $piece) {
      if ($piece != '%') {
        $pieces[] = $piece;
      }
      else {
        if (empty($args)) {
          // Try to never put % in a url; use the wildcard instead.
          if ($id && !empty($arguments[$id]['wildcard'])) {
            $pieces[] = $arguments[$id]['wildcard'];
          }
          else {
            $pieces[] = '*'; // gotta put something if there just isn't one.
          }

        }
        else {
          $pieces[] = array_shift($args);
        }

        if ($id) {
          $id = next($argument_keys);
        }
      }
    }

    if (!empty($args)) {
      $pieces = array_merge($pieces, $args);
    }
    return implode('/', $pieces);
  }

  /**
   * Get the base path used for this view.
   */
  function get_path() {
    if (!empty($this->override_path)) {
      return $this->override_path;
    }

    if (empty($this->display_handler)) {
      if (!$this->set_display('default')) {
        return FALSE;
      }
    }
    return $this->display_handler->get_path();
  }

  /**
   * Get the breadcrumb used for this view.
   *
   * @param $set
   *   If true, use drupal_set_breadcrumb() to install the breadcrumb.
   */
  function get_breadcrumb($set = FALSE) {
    // Now that we've built the view, extract the breadcrumb.
    $base = TRUE;
    $breadcrumb = array();

    if (!empty($this->build_info['breadcrumb'])) {
      foreach ($this->build_info['breadcrumb'] as $path => $title) {
        // Check to see if the frontpage is in the breadcrumb trail; if it
        // is, we'll remove that from the actual breadcrumb later.
        if ($path == variable_get('site_frontpage', 'node')) {
          $base = FALSE;
          $title = t('Home');
        }
        if ($title) {
          $breadcrumb[] = l($title, $path, array('html' => true));
        }
      }

      if ($set) {
        if ($base) {
          $breadcrumb = array_merge(drupal_get_breadcrumb(), $breadcrumb);
        }
        drupal_set_breadcrumb($breadcrumb);
      }
    }
    return $breadcrumb;
  }

  /**
   * Is this view cacheable?
   */
  function is_cacheable() {
    return $this->is_cacheable;
  }

  /**
   * Set up query capturing.
   *
   * db_query() stores the queries that it runs in global $queries,
   * bit only if dev_query is set to true. In this case, we want
   * to temporarily override that setting if it's not and we
   * can do that without forcing a db rewrite by just manipulating
   * $conf. This is kind of evil but it works.
   */
  function start_query_capture() {
    global $conf, $queries;
    if (empty($conf['dev_query'])) {
      $this->fix_dev_query = TRUE;
      $conf['dev_query'] = TRUE;
    }

    // Record the last query key used; anything already run isn't
    // a query that we are interested in.
    $this->last_query_key = NULL;

    if (!empty($queries)) {
      $keys = array_keys($queries);
      $this->last_query_key = array_pop($keys);
    }
  }

  /**
   * Add the list of queries run during render to buildinfo.
   *
   * @see view::start_query_capture()
   */
  function end_query_capture() {
    global $conf, $queries;
    if (!empty($this->fix_dev_query)) {
      $conf['dev_query'] = FALSE;
    }

    // make a copy of the array so we can manipulate it with array_splice.
    $temp = $queries;

    // Scroll through the queries until we get to our last query key.
    // Unset anything in our temp array.
    if (isset($this->last_query_key)) {
      while (list($id, $query) = each($queries)) {
        if ($id == $this->last_query_key) {
          break;
        }

        unset($temp[$id]);
      }
    }

    $this->additional_queries = $temp;
  }

  /**
   * Load a view from the database based upon either vid or name.
   *
   * This is a static factory method that implements internal caching for
   * view objects.
   *
   * @param $arg
   *  The name of the view or its internal view id (vid)
   * @param $reset
   *  If TRUE, reset this entry in the load cache.
   * @return A view object or NULL if it was not available.
   */
  function &load($arg, $reset = FALSE) {
    static $cache = array();

    // We want a NULL value to return TRUE here, so we can't use isset() or empty().
    if (!array_key_exists($arg, $cache) || $reset) {
      $where = (is_numeric($arg) ? "vid =  %d" : "name = '%s'");
      $data = db_fetch_object(db_query("SELECT * FROM {views_view} WHERE $where", $arg));
      if (empty($data)) {
        $cache[$arg] = NULL;
      }
      else {
        $view = new view();
        $view->load_row($data);
        $view->type = t('Normal');
        // Load all of our subtables.
        foreach ($view->db_objects() as $key) {
          $object_name = "views_$key";
          $result = db_query("SELECT * FROM {{$object_name}} WHERE vid = %d ORDER BY position", $view->vid);

          while ($data = db_fetch_object($result)) {
            $object = new $object_name(FALSE);
            $object->load_row($data);

            // Because it can get complicated with this much indirection,
            // make a shortcut reference.
            $location = &$view->$key;

            // If we have a basic id field, load the item onto the view based on
            // this ID, otherwise push it on.
            if (!empty($object->id)) {
              $location[$object->id] = $object;
            }
            else {
              $location[] = $object;
            }
          }
        }

        $view->loaded = TRUE;
        $cache[$arg] = $view;
      }
    }

    return $cache[$arg];
  }

  /**
   * Static factory method to load a list of views based upon a $where clause.
   *
   * Although this method could be implemented to simply iterate over views::load(),
   * that would be very slow.  Buiding the views externally from unified queries is
   * much faster.
   */
  function load_views() {
    $result = db_query("SELECT DISTINCT v.* FROM {views_view} v");
    $views = array();
    $vids = array();

    // Load all the views.
    while ($data = db_fetch_object($result)) {
      $view = new view;
      $view->load_row($data);
      $view->loaded = TRUE;
      $view->type = t('Normal');
      $views[$view->name] = $view;
      $names[$view->vid] = $view->name;
    }

    // Stop if we didn't get any views.
    if (!$views) {
      return array();
    }

    $vids = implode(', ', array_keys($names));
    // Now load all the subtables:
    foreach (view::db_objects() as $key) {
      $object_name = "views_$key";
      $result = db_query("SELECT * FROM {{$object_name}} WHERE vid IN ($vids) ORDER BY vid, position");

      while ($data = db_fetch_object($result)) {
        $object = new $object_name(FALSE);
        $object->load_row($data);

        // Because it can get complicated with this much indirection,
        // make a shortcut reference.
        $location = &$views[$names[$object->vid]]->$key;

        // If we have a basic id field, load the item onto the view based on
        // this ID, otherwise push it on.
        if (!empty($object->id)) {
          $location[$object->id] = $object;
        }
        else {
          $location[] = $object;
        }
      }
    }
    return $views;
  }

  /**
   * Save the view to the database. If the view does not already exist,
   * A vid will be assigned to the view and also returned from this function.
   */
  function save() {
    if ($this->vid == 'new') {
      $this->vid = NULL;
    }

    // If we have no vid or our vid is a string, this is a new view.
    if (!empty($this->vid)) {
      // remove existing table entries
      foreach ($this->db_objects() as $key) {
        db_query("DELETE from {views_" . $key . "} WHERE vid = %d", $this->vid);
      }
    }

    $this->save_row(!empty($this->vid) ? 'vid' : FALSE);

    // Save all of our subtables.
    foreach ($this->db_objects() as $key) {
      $this->_save_rows($key);
    }

    cache_clear_all('views_urls', 'cache_views');
    cache_clear_all(); // clear the page cache as well.
  }

  /**
   * Save a row to the database for the given key, which is one of the
   * keys from view::db_objects()
   */
  function _save_rows($key) {
    $count = 0;
    foreach ($this->$key as $position => $object) {
      $object->position = ++$count;
      $object->vid = $this->vid;
      $object->save_row();
    }
  }

  /**
   * Delete the view from the database.
   */
  function delete($clear = TRUE) {
    if (empty($this->vid)) {
      return;
    }

    db_query("DELETE FROM {views_view} WHERE vid = %d", $this->vid);
    // Delete from all of our subtables as well.
    foreach ($this->db_objects() as $key) {
      db_query("DELETE from {views_" . $key . "} WHERE vid = %d", $this->vid);
    }

    cache_clear_all('views_query:' . $this->name, 'cache_views');

    if ($clear) {
      cache_clear_all(); // this clears the block and page caches only.
      menu_rebuild(); // force a menu rebuild when a view is deleted.
    }
  }

  /**
   * Export a view as PHP code.
   */
  function export($indent = '') {
    $this->init_display();
    $output = '';
    $output .= $this->export_row('view', $indent);
    // Set the API version
    $output .= $indent . '$view->api_version = \'' . views_api_version() . "';\n";
    $output .= $indent . '$view->disabled = FALSE; /* Edit this to true to make a default view disabled initially */' . "\n";

    foreach ($this->display as $id => $display) {
      $output .= $indent . '$handler = $view->new_display(' . views_var_export($display->display_plugin, $indent) . ', ' . views_var_export($display->display_title, $indent) . ', \'' . $id . "');\n";
      if (empty($display->handler)) {
        // @todo -- probably need a method of exporting broken displays as
        // they may simply be broken because a module is not installed. That
        // does not invalidate the display.
        continue;
      }

      foreach ($display->handler->option_definition() as $option => $definition) {
        // Special handling for some items
        switch ($option) {
          case 'defaults':
            // skip these
            break;
          default:
            if (!$display->handler->is_defaulted($option)) {
              $value = $display->handler->get_option($option);
              if ($id == 'default') {
                $default = isset($definition['default']) ? $definition['default'] : NULL;
              }
              else {
                $default = $this->display['default']->handler->get_option($option);
              }

              if ($value !== $default) {
                $output .= $indent . '$handler->override_option(\'' . $option . '\', ' . views_var_export($value, $indent) . ");\n";
              }
            }
        }
      }
    }

    return $output;
  }

  /**
   * Make a copy of this view that has been sanitized of all database IDs
   * and handlers and other stuff.
   *
   * I'd call this clone() but it's reserved.
   */
  function copy() {
    $code = $this->export();
    eval($code);
    return $view;
  }

  /**
   * Safely clone a view.
   *
   * Because views are complicated objects within objects, and PHP loves to
   * do references to everything, if a View is not properly and safely
   * cloned it will still have references to the original view, and can
   * actually cause the original view to point to objects in the cloned
   * view. This gets ugly fast.
   *
   * This will completely wipe a view clean so it can be considered fresh.
   */
  function clone_view() {
    $clone = version_compare(phpversion(), '5.0') < 0 ? $this : clone($this);

    $keys = array('current_display', 'display_handler', 'build_info', 'built', 'executed', 'attachment_before', 'attachment_after', 'field', 'argument', 'filter', 'sort', 'relationship', 'query', 'inited', 'style_plugin', 'plugin_name', 'exposed_data', 'exposed_input', 'exposed_widgets', 'many_to_one_tables', 'feed_icon');
    foreach ($keys as $key) {
      if (isset($clone->$key)) {
        unset($clone->$key);
      }
    }
    $clone->built = $clone->executed = FALSE;
    $clone->build_info = array();
    $clone->attachment_before = '';
    $clone->attachment_after = '';
    $clone->result = array();

    // shallow cloning means that all the display objects
    // *were not cloned*. We must clone them ourselves.
    $displays = array();
    foreach ($clone->display as $id => $display) {
      $displays[$id] = drupal_clone($display);
      if (isset($displays[$id]->handler)) {
        unset($displays[$id]->handler);
      }
    }
    $clone->display = $displays;

    return $clone;
  }

  /**
   * Unset references so that a $view object may be properly garbage
   * collected.
   */
  function destroy() {
    foreach (array_keys($this->display) as $display_id) {
      if (isset($this->display[$display_id]->handler)) {
        $this->display[$display_id]->handler->destroy();
        unset($this->display[$display_id]->handler);
      }
    }

    foreach (views_object_types() as $type => $info) {
      if (isset($this->$type)) {
        $handlers = &$this->$type;
        foreach ($handlers as $id => $item) {
          $handlers[$id]->destroy();
        }
        unset($handlers);
      }
    }

    if (isset($this->style_plugin)) {
      $this->style_plugin->destroy();
      unset($this->style_plugin);
    }

    // Clear these to make sure the view can be processed/used again.
    if (isset($this->display_handler)) {
      unset($this->display_handler);
    }

    if (isset($this->current_display)) {
      unset($this->current_display);
    }

    if (isset($this->query)) {
      unset($this->query);
    }
  }

  /**
   * Make sure the view is completely valid.
   *
   * @return
   *   TRUE if the view is valid; an array of error strings if it is not.
   */
  function validate() {
    $this->init_display();

    $errors = array();

    $current_display = $this->current_display;
    foreach ($this->display as $id => $display) {
      if ($display->handler) {
        if (!empty($display->deleted)) {
          continue;
        }
        $this->set_display($id);

        $result = $this->display[$id]->handler->validate();
        if (!empty($result) && is_array($result)) {
          $errors = array_merge($errors, $result);
        }
      }
    }

    $this->set_display($current_display);
    return $errors ? $errors : TRUE;
  }
}

/**
 * Base class for views' database objects.
 */
class views_db_object {
  /**
   * Initialize this object, setting values from schema defaults.
   *
   * @param $init
   *   If an array, this is a set of values from db_fetch_object to
   *   load. Otherwse, if TRUE values will be filled in from schema
   *   defaults.
   */
  function init($init = TRUE) {
    if (is_array($init)) {
      return $this->load_row($init);
    }

    if (!$init) {
      return;
    }

    $schema = drupal_get_schema($this->db_table);

    if (!$schema) {
      return;
    }

    // Go through our schema and build correlations.
    foreach ($schema['fields'] as $field => $info) {
      if ($info['type'] == 'serial') {
        $this->$field = NULL;
      }
      if (!isset($this->$field)) {
        if (!empty($info['serialize']) && isset($info['serialized default'])) {
          $this->$field = unserialize($info['serialized default']);
        }
        else if (isset($info['default'])) {
          $this->$field = $info['default'];
        }
        else {
          $this->$field = '';
        }
      }
    }
  }

  /**
   * Write the row to the database.
   *
   * @param $update
   *   If true this will be an UPDATE query. Otherwise it will be an INSERT.
   */
  function save_row($update = NULL) {
    $schema = drupal_get_schema($this->db_table);
    $fields = $defs = $values = $serials = array();

    // Go through our schema and build correlations.
    foreach ($schema['fields'] as $field => $info) {
      // special case -- skip serial types if we are updating.
      if ($info['type'] == 'serial') {
        $serials[] = $field;
        continue;
      }
      $fields[] = $field;
      switch ($info['type']) {
        case 'blob':
          $defs[] = '%b';
          break;
        case 'int':
          $defs[] = '%d';
          break;
        case 'float':
        case 'numeric':
          $defs[] = '%f';
          break;
        default:
          $defs[] = "'%s'";
      }
      if (empty($info['serialize'])) {
        $values[] = $this->$field;
      }
      else {
        $values[] = serialize($this->$field);
      }
    }
    $query = '';
    if (!$update) {
      $query = "INSERT INTO {" . $this->db_table . "} (" . implode(', ', $fields) . ') VALUES (' . implode(', ', $defs) . ')';
    }
    else {
      $query = '';
      foreach ($fields as $id => $field) {
        if ($query) {
          $query .= ', ';
        }
        $query .= $field . ' = ' . $defs[$id];
      }
      $query = "UPDATE {" . $this->db_table . "} SET " . $query . " WHERE $update = " . $this->$update;
    }
    db_query($query, $values);

    if ($serials && !$update) {
      // get last insert ids and fill them in.
      foreach ($serials as $field) {
        $this->$field = db_last_insert_id($this->db_table, $field);
      }
    }
  }

  /**
   * Load the object with a row from the database.
   *
   * This method is separate from the constructor in order to give us
   * more flexibility in terms of how the view object is built in different
   * contexts.
   *
   * @param $data
   *   An object from db_fetch_object. It should contain all of the fields
   *   that are in the schema.
   */
  function load_row($data) {
    $schema = drupal_get_schema($this->db_table);

    // Go through our schema and build correlations.
    foreach ($schema['fields'] as $field => $info) {
      $this->$field = empty($info['serialize']) ? $data->$field : unserialize(db_decode_blob($data->$field));
    }
  }

  /**
   * Export a loaded row, such as an argument, field or the view itself to PHP code.
   *
   * @param $identifier
   *   The variable to assign the PHP code for this object to.
   * @param $indent
   *   An optional indentation for prettifying nested code.
   */
  function export_row($identifier = NULL, $indent = '') {
    if (!$identifier) {
      $identifier = $this->db_table;
    }
    $schema = drupal_get_schema($this->db_table);

    $output = $indent . '$' . $identifier . ' = new ' . get_class($this) . ";\n";
    // Go through our schema and build correlations.
    foreach ($schema['fields'] as $field => $info) {
      if (!empty($info['no export'])) {
        continue;
      }
      if (!isset($this->$field)) {
        if (isset($info['default'])) {
          $this->$field = $info['default'];
        }
        else {
          $this->$field = '';
        }

        // serialized defaults must be set as serialized.
        if (isset($info['serialize'])) {
          $this->$field = unserialize(db_decode_blob($this->$field));
        }
      }
      $value = $this->$field;
      if ($info['type'] == 'int') {
        $value = ($info['size'] == 'tiny') ? (bool) $value : (int) $value;
      }

      $output .= $indent . '$' . $identifier . '->' . $field . ' = ' . views_var_export($value, $indent) . ";\n";
    }
    return $output;
  }

  /**
   * Add a new display handler to the view, automatically creating an id.
   *
   * @param $type
   *   The plugin type from the views plugin data. Defaults to 'page'.
   * @param $title
   *   The title of the display; optional, may be filled in from default.
   * @param $id
   *   The id to use.
   * @return
   *   The key to the display in $view->display, so that the new display
   *   can be easily located.
   */
  function add_display($type = 'page', $title = NULL, $id = NULL) {
    if (empty($type)) {
      return FALSE;
    }

    $plugin = views_fetch_plugin_data('display', $type);
    if (empty($plugin)) {
      $plugin['title'] = t('Broken');
    }


    if (empty($id)) {
      $title = $plugin['title'];

      $id = $this->generate_display_id($type);
      $count = str_replace($type . '_', '', $id);
      if (empty($title)) {
        $title = $plugin['title'] . ' ' . $count;
      }
    }

    // Create the new display object
    $display = new views_display;
    $display->options($type, $id, $title);

    // Add the new display object to the view.
    $this->display[$id] = $display;
    return $id;
  }

  /**
   * Generate a display id of a certain plugin type.
   *
   * @param $type
   *   Which plugin should be used for the new display id.
   */
  function generate_display_id($type) {
    // 'default' is singular and is unique, so just go with 'default'
    // for it. For all others, start counting.
    if ($type == 'default') {
      return 'default';
    }
    // Initial id.
    $id = $type . '_1';
    $count = 1;

    // Loop through IDs based upon our style plugin name until
    // we find one that is unused.
    while (!empty($this->display[$id])) {
      $id = $type . '_' . ++$count;
    }

    return $id;
  }

  /**
   * Create a new display and a display handler for it.
   * @param $type
   *   The plugin type from the views plugin data. Defaults to 'page'.
   * @param $title
   *   The title of the display; optional, may be filled in from default.
   * @param $id
   *   The id to use.
   * @return
   *   A reference to the new handler object.
   */
  function &new_display($type = 'page', $title = NULL, $id = NULL) {
    $id = $this->add_display($type, $title, $id);

    // Create a handler
    $this->display[$id]->handler = views_get_plugin('display', $this->display[$id]->display_plugin);
    if (empty($this->display[$id]->handler)) {
      // provide a 'default' handler as an emergency. This won't work well but
      // it will keep things from crashing.
      $this->display[$id]->handler = views_get_plugin('display', 'default');
    }

    if (!empty($this->display[$id]->handler)) {
      // Initialize the new display handler with data.
      $this->display[$id]->handler->init($this, $this->display[$id]);
      // If this is NOT the default display handler, let it know which is
      if ($id != 'default') {
        $this->display[$id]->handler->default_display = &$this->display['default']->handler;
      }
    }

    return $this->display[$id]->handler;
  }

  /**
   * Add an item with a handler to the view.
   *
   * These items may be fields, filters, sort criteria, or arguments.
   */
  function add_item($display_id, $type, $table, $field, $options = array(), $id = NULL) {
    $types = views_object_types();
    $this->set_display($display_id);

    $fields = $this->display[$display_id]->handler->get_option($types[$type]['plural']);

    if (empty($id)) {
      $count = 0;
      $id = $field;
      while (!empty($fields[$id])) {
        $id = $field . '_' . ++$count;
      }
    }

    $new_item = array(
      'id' => $id,
      'table' => $table,
      'field' => $field,
    ) + $options;

    $handler = views_get_handler($table, $field, $type);

    $fields[$id] = $new_item;
    $this->display[$display_id]->handler->set_option($types[$type]['plural'], $fields);

    return $id;
  }

  /**
   * Get an array of items for the current display.
   */
  function get_items($type, $display_id = NULL) {
    $this->set_display($display_id);

    if (!isset($display_id)) {
      $display_id = $this->current_display;
    }

    // Get info about the types so we can get the right data.
    $types = views_object_types();
    return $this->display[$display_id]->handler->get_option($types[$type]['plural']);
  }

  /**
   * Get the configuration of an item (field/sort/filter/etc) on a given
   * display.
   */
  function get_item($display_id, $type, $id) {
    // Get info about the types so we can get the right data.
    $types = views_object_types();
    // Initialize the display
    $this->set_display($display_id);

    // Get the existing configuration
    $fields = $this->display[$display_id]->handler->get_option($types[$type]['plural']);

    return isset($fields[$id]) ? $fields[$id] : NULL;
  }

  /**
   * Get the configuration of an item (field/sort/filter/etc) on a given
   * display.
   *
   * Pass in NULL for the $item to remove an item.
   */
  function set_item($display_id, $type, $id, $item) {
    // Get info about the types so we can get the right data.
    $types = views_object_types();
    // Initialize the display
    $this->set_display($display_id);

    // Get the existing configuration
    $fields = $this->display[$display_id]->handler->get_option($types[$type]['plural']);
    if (isset($item)) {
      $fields[$id] = $item;
    }
    else {
      unset($fields[$id]);
    }

    // Store.
    $this->display[$display_id]->handler->set_option($types[$type]['plural'], $fields);
  }

  /**
   * Set an option on an item.
   *
   * Use this only if you have just 1 or 2 options to set; if you have
   * many, consider getting the item, adding the options and doing
   * set_item yourself.
   */
  function set_item_option($display_id, $type, $id, $option, $value) {
    $item = $this->get_item($display_id, $type, $id);
    $item[$option] = $value;
    $this->set_item($display_id, $type, $id, $item);
  }
}

/**
 * A display type in a view.
 *
 * This is just the database storage mechanism, and isn't terribly important
 * to the behavior of the display at all.
 */
class views_display extends views_db_object {
  var $db_table = 'views_display';
  function views_display($init = TRUE) {
    parent::init($init);
  }

  function options($type, $id, $title) {
    $this->display_plugin = $type;
    $this->id = $id;
    $this->display_title = $title;
  }
}

/**
 * Provide a list of views object types used in a view, with some information
 * about them.
 */
function views_object_types() {
  static $retval = NULL;

  // statically cache this so t() doesn't run a bajillion times.
  if (!isset($retval)) {
    $retval = array(
      'field' => array(
        'title' => t('Fields'), // title
        'ltitle' => t('fields'), // lowercase title for mid-sentence
        'stitle' => t('Field'), // singular title
        'lstitle' => t('field'), // singular lowercase title for mid sentence
        'plural' => 'fields',
      ),
      'argument' => array(
        'title' => t('Arguments'),
        'ltitle' => t('arguments'),
        'stitle' => t('Argument'),
        'lstitle' => t('Argument'),
        'plural' => 'arguments',
      ),
      'sort' => array(
        'title' => t('Sort criteria'),
        'ltitle' => t('sort criteria'),
        'stitle' => t('Sort criterion'),
        'lstitle' => t('sort criterion'),
        'plural' => 'sorts',
      ),
      'filter' => array(
        'title' => t('Filters'),
        'ltitle' => t('filters'),
        'stitle' => t('Filter'),
        'lstitle' => t('filter'),
        'plural' => 'filters',
        'options' => 'views_ui_config_filters_form',
      ),
      'relationship' => array(
        'title' => t('Relationships'),
        'ltitle' => t('relationships'),
        'stitle' => t('Relationship'),
        'lstitle' => t('Relationship'),
        'plural' => 'relationships',
      ),
    );
  }

  return $retval;
}

/**
 * @}
 */