privatecollectionswp /htdocs/wp-content/plugins/nextgen-gallery/pope/lib/class.extensibleobject.php

Language PHP Lines 1419
MD5 Hash d418e066caba0aa6c52413035f79eedc
Repository https://github.com/Fishgate/privatecollectionswp.git View Raw File View Project SPDX
   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
<?php
define('__EXTOBJ_STATIC__', '__STATICALLY_CALLED__');
define('__EXTOBJ_NO_INIT__', '__NO_INIT__');

if (!defined('EXTENSIBLE_OBJECT_ENFORCE_INTERFACES')) {
    define('EXTENSIBLE_OBJECT_ENFORCE_INTERFACES', TRUE);
}


/**
 * Provides helper methods for Pope objects
 */
class PopeHelpers
{
    /**
     * Merges two associative arrays
     * @param array $a1
     * @param array $a2
     * @return array
     */
    function array_merge_assoc($a1, $a2, $skip_empty=FALSE)
    {
		if ($a2) {
			foreach ($a2 as $key => $value) {
				if ($skip_empty && $value === '' OR is_null($value)) continue;
				if (isset($a1[$key])) {

					if (is_array($value)) {
						$a1[$key] = $this->array_merge_assoc($a1[$key], $value);

					}
					else {
						$a1[$key] = $value;
					}

				}
				else $a1[$key] = $value;
			}
		}
		return $a1;
    }


    /**
     * Returns TRUE if a property is empty
     * @param string $var
     * @return boolean
     */
    function is_empty($var, $element=FALSE)
    {
       if (is_array($var) && $element) {
           if (isset($var[$element])) $var = $var[$element];
           else $var = FALSE;
       }

       return (is_null($var) OR (is_string($var) AND strlen($var) == 0) OR $var === FALSE);
    }
}


/**
 * An ExtensibleObject can be extended at runtime with methods from another
 * class.
 *
 * - Mixins may be added or removed at any time during runtime
 * - The path to the mixin is cached so that subsequent method calls are
 *   faster
 * - Pre and post hooks can be added or removed at any time during runtime.
 * - Each method call has a list of associated properties that can be modified
 *   by pre/post hooks, such as: return_value, run_pre_hooks, run_post_hooks, etc
 * - Methods can be replaced by other methods at runtime
 * - Objects can implement interfaces, and are constrained to implement all
 *   methods as defined by the interface
 * - All methods are public. There's no added security by having private/protected
 *   members, as monkeypatching can always expose any method. Instead, protect
 *   your methods using obscurity. Conventionally, use an underscore to define
 *   a method that's private to an API
 */
class ExtensibleObject extends PopeHelpers
{
    const METHOD_PROPERTY_RUN='run';
    const METHOD_PROPERTY_RUN_POST_HOOKS='run_post_hooks';
    const METHOD_PROPERTY_RUN_PRE_HOOKS='run_pre_hooks';
    const METHOD_PROPERTY_RETURN_VALUE='return_value';

    var  $_mixins = array();
    var  $_mixin_priorities = array();
    var  $_pre_hooks = array();
    var  $_global_pre_hooks = array();
    var  $_global_post_hooks= array();
    var  $_post_hooks = array();
    var  $_method_map_cache = array();
    var  $_interfaces = array();
    var  $_overrides = array();
    var  $_aliases = array();
    var  $_method_properties = array();
    var  $_throw_error = TRUE;
    var  $_wrapped_instance = FALSE;
	var	 $object = NULL;
	var  $_disabled_pre_hooks = array();
	var  $_disabled_post_hooks = array();
	var  $_disabled_mixins = array();


    /**
     * Defines a new ExtensibleObject. Any subclass should call this constructor.
     * Subclasses are expected to provide the following:
     * define_instance() - adds extensions which provide instance methods
     * define_class() - adds extensions which provide static methods
     * initialize() - used to initialize the state of the object
     */
    function __construct()
    {
		// Mixins access their parent class by accessing $this->object.
		// Sometimes users mistakenly use $this->object within the parent object
		// itself. As it's becoming a common mistake, we define a $this->object
		// property which points to the current instance (itself)
		$this->object = $this;

        $args = func_get_args();
        $define_instance = TRUE;
        $init_instance = TRUE;

        // The first argument could be a flag to ExtensibleObject
        // which indicates that only static-like methods will be called
        if (count($args) >= 1) {
            $first_arg = $args[0];
            if (is_string($first_arg)) {
            	switch ($first_arg) {
            		case __EXTOBJ_STATIC__:
            		{
		              $define_instance = FALSE;
		              $init_instance = FALSE;

		              if (method_exists($this, 'define_class')) {
						  $this->call_callback($this, 'define_class', $args);
		              }
		              elseif (method_exists($this, 'define_static')) {
						  $this->call_callback($this, 'define_static', $args);
		              }

					  break;
            		}
            		case __EXTOBJ_NO_INIT__:
            		{
		              $init_instance = FALSE;

            			break;
            		}
            	}
            }
        }

        // Are we to define instance methods?
        if ($define_instance)
        {
            if (method_exists($this, 'define_instance'))
            {
                $reflection = new ReflectionMethod($this, 'define_instance');
                $reflection->invokeArgs($this, $args);
                // call_user_func_array(array($this, 'define_instance'), $args);
            }
            elseif (method_exists($this, 'define')) {
                $reflection = new ReflectionMethod($this, 'define');
                $reflection->invokeArgs($this, $args);
                // call_user_func_array(array($this, 'define'), $args);
            }

            if (EXTENSIBLE_OBJECT_ENFORCE_INTERFACES) $this->_enforce_interface_contracts();

			if ($init_instance)
            {
                // Initialize the state of the object
                if (method_exists($this, 'initialize')) {
                    $reflection = new ReflectionMethod($this, 'initialize');
                    $reflection->invokeArgs($this, $args);
                    // call_user_func_array(array($this, 'initialize'), $args);
                }
            }
        }
    }

	/**
	 * Disabled prehooks for a particular method
	 * @param string $method
	 */
	function disable_pre_hooks($method)
	{
		$this->_disabled_pre_hooks[] = $method;
		return $this;
	}


	/**
	 * Enable prehooks for a particular method
	 * @param string $method
	 */
	function enable_pre_hooks($method)
	{
		$index = array_search($method, $this->_disabled_pre_hooks);
		if ($index !== FALSE) {
			unset($this->_disabled_pre_hooks[$index]);
		}
		return $this;
	}

	/**
	 * Disabled posthooks for a particular method
	 * @param string $method
	 */
	function disable_post_hooks($method)
	{
		$this->_disabled_post_hooks[] = $method;
		return $this;
	}


	/**
	 * Enable post-hooks for a particular method
	 * @param string $method
	 */
	function enable_post_hooks($method)
	{
		$index = array_search($method, $this->_disabled_post_hooks);
		if ($index !== FALSE) {
			unset($this->_disabled_post_hooks[$index]);
		}
		return $this;
	}

	/**
	 * Determines if post hooks are enabled for a particular method
	 * @param string $method
	 * @return bool
	 */
	function are_post_hooks_enabled($method)
	{
		return !empty($this->_post_hooks) && (!in_array($method, $this->_disabled_post_hooks));
	}


	/**
	 * Determines if pre hooks are enabled for a particular method
	 * @param string $method
	 * @return bool
	 */
	function are_pre_hooks_enabled($method)
	{
		return !empty($this->_pre_hooks) && (!in_array($method, $this->_disabled_pre_hooks));
	}


    /**
     * Adds an extension class to the object. The extension provides
     * methods for this class to expose as it's own
     * @param string $class
     */
    function add_mixin($class, $instantiate=FALSE)
    {
		$retval = TRUE;

		if (!$this->has_mixin($class)) {
			// We used to instantiate the class, but I figure
			// we might as well wait till the method is called to
			// save memory. Instead, the _call() method calls the
			// _instantiate_mixin() method below.
			$this->_mixins[$class] = FALSE; // new $class();
			array_unshift($this->_mixin_priorities, $class);
			$this->_flush_cache();

			// Should we instantiate the object now?
			if ($instantiate) $this->_instantiate_mixin($class);
		}
		else $retval = FALSE;

		return $retval;
    }


	/**
	 * Determines if a mixin has been added to this class
	 * @param string $klass
	 * @return bool
	 */
	function has_mixin($klass)
	{
		return (isset($this->_mixins[$klass]));
	}


    /**
     * Stores the instantiated class
     * @param string $class
     * @return mixed
     */
    function _instantiate_mixin($class)
    {
        $retval = FALSE;
        if ($this->_mixins[$class])
            $retval = $this->_mixins[$class];
        else {
            $obj= new $class();
            $obj->object = &$this;
            $retval = $this->_mixins[$class] = &$obj;
            if (method_exists($obj, 'initialize')) $obj->initialize();
        }


        return $retval;
    }


    /**
     * Deletes an extension from the object. The methods provided by that
     * extension are no longer available for the object
     * @param string $class
     */
    function del_mixin($class)
    {
        unset($this->_mixins[$class]);
        $index = array_search($class, $this->_mixin_priorities);
        if ($index !== FALSE) {
            unset($this->_mixin_priorities[$index]);
			foreach ($this->_disabled_mixins as $method => $disabled_mixins) {
				$index = array_search($class, $disabled_mixins);
				if (is_int($index)) unset($this->_disabled_mixins[$method][$index]);
			}
            $this->_flush_cache();
        }

    }


    function remove_mixin($class)
    {
        $this->del_mixin($class);
    }


    /**
     * Replaces an extension methods with that of another class.
     * @param string $method
     * @param string $class
     * @param string $new_method
     */
    function replace_method($method, $class, $new_method=FALSE)
    {
        if (!$new_method) $new_method = $method;
        $this->_overrides[$method] = $class;
        $this->add_pre_hook($method, "replacement_{$method}_{$class}_{$new_method}", $class, $new_method);
        $this->_flush_cache();

    }


    /**
     * Restores a method that was replaced by a former call to replace_method()
     * @param string $method
     */
    function restore_method($method)
    {
        $class = $this->_overrides[$method];
        unset($this->_overrides[$method]);
        $this->del_pre_hook($method, $class);
        $this->_flush_cache();
    }


	/**
	 * Returns the Mixin which provides the specified method
	 * @param string $method
	 */
	function get_mixin_providing($method, $return_obj=FALSE)
	{
		$retval = FALSE;

		// If it's cached, then we've got it easy
		if ($this->is_cached($method)) {

			$object = $this->_method_map_cache[$method];
			$retval = get_class($object);
		}

		// Otherwise, we have to look it up
		else {
            foreach ($this->get_mixin_priorities($method) as $klass) {
                $object = $this->_instantiate_mixin($klass);
                if (method_exists($object, $method)) {
                    $retval = $return_obj ? $object : get_class($object);
                    $this->_cache_method($object, $method);
                    break;
                }
            }
		}

		return $retval;
	}


    /**
     * When an ExtensibleObject is instantiated, it checks whether all
     * the registered extensions combined provide the implementation as required
     * by the interfaces registered for this object
     */
    function _enforce_interface_contracts()
    {
        $errors = array();

        foreach ($this->_interfaces as $i) {
            $r = new ReflectionClass($i);
            foreach ($r->getMethods() as $m) {
                if (!$this->has_method($m->name)) {
					$klass = $this->get_class_name($this);
                    $errors[] = "`{$klass}` does not implement `{$m->name}` as required by `{$i}`";
                }
            }
        }

        if ($errors) throw new Exception(implode(". ", $errors));
    }


    /**
     * Implement a defined interface. Does the same as the 'implements' keyword
     * for PHP, except this method takes into account extensions
     * @param string $interface
     */
    function implement($interface)
    {
        $this->_interfaces[] = $interface;
    }


    /**
     * Adds a hook that gets executed before every method call
     * @param string $name
     * @param string $class
     * @param string $hook_method
     */
    function add_global_pre_hook($name, $class, $hook_method)
    {
        $this->add_pre_hook('*', $name, $class, $hook_method);
    }

    /**
     * Adds a hook that gets executed after every method call
     *
     * @param string $name
     * @param string $class
     * @param string $hook_method
     */
    function add_global_post_hook($name, $class, $hook_method)
    {
        $this->add_pre_hook('*', $name, $class, $hook_method);
    }


    /**
     * Adds a hook that will get executed before a particular method call
     * @param string $method
     * @param string $name
     * @param string $class
     * @param string $hook_method
     */
    function add_pre_hook($method, $name, $class, $hook_method=FALSE)
    {
        if (!$hook_method) $hook_method = $method;

        // Is this a global pre hook?
        if ($method == '*') {
            $this->_global_pre_hooks[$name] = array(
                new $class,
                $hook_method
            );
        }

        // This is a method-specific pre hook
        else {
            if (!isset($this->_pre_hooks[$method])) {
                $this->_pre_hooks[$method] = array();
            }

            $this->_pre_hooks[$method][$name] = array(
                new $class,
                $hook_method
            );
        }
    }


    /**
     * Adds a hook to be called after a particular method call
     * @param string $method
     * @param string $hook_name
     * @param string $class
     * @param string $hook_method
     */
    function add_post_hook($method, $hook_name, $class, $hook_method=FALSE)
    {
        // Is this a global post hook?
        if ($method == '*') {
            $this->_post_hooks[$hook_name] = array(
              new $class,
                $hook_method
            );
        }

        // This is a method-specific post hook
        else {
            if (!$hook_method) $hook_method = $method;

            if (!isset($this->_post_hooks[$method])) {
                $this->_post_hooks[$method] = array();
            }

            $this->_post_hooks[$method][$hook_name] = array(
                new $class,
                $hook_method
            );
        }
    }


    /**
     * Deletes a hook that's executed before the specified method
     * @param string $method
     * @param string $name
     */
    function del_pre_hook($method, $name)
    {

        unset($this->_pre_hooks[$method][$name]);
    }

    /**
     * Deletes all pre hooks registered
    **/
    function del_pre_hooks($method=FALSE)
    {
        if (!$method)
            $this->_pre_hooks = array();
        else
            unset($this->_pre_hooks[$method]);
    }


    /**
     * Deletes a hook that's executed after the specified method
     * @param string $method
     * @param string $name
     */
    function del_post_hook($method, $name)
    {
        unset($this->_post_hooks[$method][$name]);
    }

    /**
     * Deletes all post hooks
     */
    function del_post_hooks($method=FALSE)
    {
        if (!$method)
            $this->_post_hooks = array();
        else
            unset($this->_post_hooks[$method]);
    }


    /**
     * Wraps a class within an ExtensibleObject class.
     * @param string $klass
     * @param array callback, used to tell ExtensibleObject how to instantiate
     * the wrapped class
     */
    function wrap($klass, $callback=FALSE, $args=array())
    {
        if ($callback) {
            $this->_wrapped_instance = call_user_func($callback, $args);
        }
        else {
            $this->_wrapped_instance = new $klass();
        }
    }


    /**
     * Determines if the ExtensibleObject is a wrapper for an existing class
     */
    function is_wrapper()
    {
        return $this->_wrapped_instance ? TRUE : FALSE;
    }


    /**
     * Returns the name of the class which this ExtensibleObject wraps
     * @return object
     */
    function &get_wrapped_instance()
    {
        return $this->_wrapped_instance;
    }


    /**
     * Returns TRUE if the wrapped class provides the specified method
     */
    function wrapped_class_provides($method)
    {
        $retval = FALSE;

        // Determine if the wrapped class is another ExtensibleObject
        if (method_exists($this->_wrapped_instance, 'has_method')) {
			$retval = $this->_wrapped_instance->has_method($method);
        }
        elseif (method_exists($this->_wrapped_instance, $method)){
            $retval = TRUE;
        }

        return $retval;
    }


    /**
     * Provides a means of calling static methods, provided by extensions
     * @param string $method
     * @return mixed
     */
    static function get_class()
    {
		// Note: this function is static so $this is not defined
        $klass = self::get_class_name();
        $obj = new $klass(__EXTOBJ_STATIC__);
        return $obj;
    }


	/**
	 * Gets the name of the ExtensibleObject
	 * @return string
	 */
	static function get_class_name($obj = null)
	{
		if ($obj)
			return get_class($obj);
		elseif (function_exists('get_called_class'))
			return get_called_class();
		else
			return get_class();
	}

	/**
     * Gets a property from a wrapped object
     * @param string $property
     * @return mixed
     */
    function &__get($property)
    {
		$retval = NULL;
        if ($this->is_wrapper()) {
			try {
				$reflected_prop = new ReflectionProperty($this->_wrapped_instance, $property);

				// setAccessible method is only available for PHP 5.3 and above
				if (method_exists($reflected_prop, 'setAccessible')) {
					$reflected_prop->setAccessible(TRUE);
				}

				$retval = $reflected_prop->getValue($this->_wrapped_instance);
			}
			catch (ReflectionException $ex)
			{
				$retval = $this->_wrapped_instance->$property;
			}
        }

		return $retval;
    }

	/**
	 * Determines if a property (dynamic or not) exists for the object
	 * @param string $property
	 * @return boolean
	 */
	function __isset($property)
	{
		$retval = FALSE;

		if (property_exists($this, $property)) {
			$retval = isset($this->$property);
		}
		elseif ($this->is_wrapper() && property_exists($this->_wrapped_instance, $property)) {
			$retval = isset($this->$property);
		}

		return $retval;
	}


    /**
     * Sets a property on a wrapped object
     * @param string $property
     * @param mixed $value
     * @return mixed
     */
    function &__set($property, $value)
    {
		$retval = NULL;
        if ($this->is_wrapper()) {
			try {
				$reflected_prop = new ReflectionProperty($this->_wrapped_instance, $property);

				// The property must be accessible, but this is only available
				// on PHP 5.3 and above
				if (method_exists($reflected_prop, 'setAccessible')) {
					$reflected_prop->setAccessible(TRUE);
				}

				$retval = &$reflected_prop->setValue($this->_wrapped_instance, $value);
			}

			// Sometimes reflection can fail. In that case, we need
			// some ingenuity as a failback
			catch (ReflectionException $ex) {
				$this->_wrapped_instance->$property = $value;
				$retval = &$this->_wrapped_instance->$property;
			}

        }
		else {
			$this->$property = $value;
			$retval = &$this->$property;
		}
        return $retval;
    }


    /**
     * Finds a method defined by an extension and calls it. However, execution
     * is a little more in-depth:
     * 1) Execute all global pre-hooks and any pre-hooks specific to the requested
     *    method. Each method call has instance properties that can be set by
     *    other hooks to modify the execution. For example, a pre hook can
     *    change the 'run_pre_hooks' property to be false, which will ensure that
     *    all other pre hooks will NOT be executed.
     * 2) Runs the method. Checks whether the path to the method has been cached
     * 3) Execute all global post-hooks and any post-hooks specific to the
     *    requested method. Post hooks can access method properties as well. A
     *    common usecase is to return the value of a post hook instead of the
     *    actual method call. To do this, set the 'return_value' property.
     * @param string $method
     * @param array $args
     * @return mixed
     */
    function __call($method, $args)
    {
        $this->reset_method_properties($method, $args);

        // Run pre hooks?
        if ($this->are_pre_hooks_enabled($method) && $this->get_method_property($method, self::METHOD_PROPERTY_RUN_PRE_HOOKS)) {

            // Combine global and method-specific pre hooks
            $prehooks = $this->_global_pre_hooks;
            if (isset($this->_pre_hooks[$method])) {
                $prehooks = array_merge($prehooks, $this->_pre_hooks[$method]);
            }

            // Apply each hook
            foreach ($prehooks as $hook_name => $hook) {
				$method_args = $this->get_method_property($method, 'arguments', $args);
                $this->_run_prehook(
					$hook_name,
					$method,
					$hook[0],
					$hook[1],
					$method_args
				);
            }
        }

        // Are we to run the actual method? A pre hook might have told us
        // not to
        if ($this->get_method_property($method, self::METHOD_PROPERTY_RUN) && !isset($this->_overrides[$method]))
        {
            if (($this->get_mixin_providing($method))) {
                $this->set_method_property(
                    $method,
                    self::METHOD_PROPERTY_RETURN_VALUE,
                    $this->_exec_cached_method($method, $this->get_method_property($method, 'arguments'))
                );
            }

            // This is NOT a wrapped class, and no extensions provide the method
            else {
                // Perhaps this is a wrapper and the wrapped object
                // provides this method
                if ($this->is_wrapper() && $this->wrapped_class_provides($method))
                {
                    $object = $this->add_wrapped_instance_method($method);
                    $this->set_method_property(
                        $method,
                        self::METHOD_PROPERTY_RETURN_VALUE,
                        call_user_func_array(
                            array(&$object, $method),
                            $this->get_method_property($method, 'arguments')
                        )
                    );
                }
                elseif ($this->_throw_error) {
                    throw new Exception("`{$method}` not defined for " . get_class());
                }
                else {
                    return FALSE;
                }
            }
        }

        // Are we to run post hooks? A pre hook might have told us not to
        if ($this->are_post_hooks_enabled($method) && $this->get_method_property($method, self::METHOD_PROPERTY_RUN_POST_HOOKS)) {

            // Combine global and method-specific post hooks
            $posthooks = $this->_global_post_hooks;
            if (isset($this->_post_hooks[$method])) {
                $posthooks = array_merge($posthooks, $this->_post_hooks[$method]);
            }

            // Apply each hook
            foreach ($posthooks as $hook_name => $hook) {
				$method_args = $this->get_method_property($method, 'arguments', $args);
                $this->_run_post_hook(
					$hook_name,
					$method,
					$hook[0],
					$hook[1],
					$method_args
				);
            }
        }

		// Get return value, clear all method properties, and then return
        $retval = $this->get_method_property($method, self::METHOD_PROPERTY_RETURN_VALUE);
		$this->remove_method_properties($method);
		return $retval;
    }


	/**
	 * Adds the implementation of a wrapped instance method to the ExtensibleObject
	 * @param string $method
	 * @return Mixin
	 */
	function add_wrapped_instance_method($method)
	{
		$retval = $this->get_wrapped_instance();

		// If the wrapped instance is an ExtensibleObject, then we don't need
		// to use reflection
		if (!is_subclass_of($this->get_wrapped_instance(), 'ExtensibleObject')) {
			$func	= new ReflectionMethod($this->get_wrapped_instance(), $method);

			// Get the entire method definition
			$filename = $func->getFileName();
			$start_line = $func->getStartLine() - 1; // it's actually - 1, otherwise you wont get the function() block
			$end_line = $func->getEndLine();
			$length = $end_line - $start_line;
			$source = file($filename);
			$body = implode("", array_slice($source, $start_line, $length));
            $body = preg_replace("/^\s{0,}private|protected\s{0,}/", '', $body);

			// Change the context
			$body = str_replace('$this', '$this->object', $body);
			$body = str_replace('$this->object->object', '$this->object', $body);
			$body = str_replace('$this->object->$', '$this->object->', $body);

			// Define method for mixin
			$wrapped_klass = get_class($this->get_wrapped_instance());
			$mixin_klass = "Mixin_AutoGen_{$wrapped_klass}_{$method}";
			if (!class_exists($mixin_klass)) {
				eval("class {$mixin_klass} extends Mixin{
					{$body}
				}");
			}
			$this->add_mixin($mixin_klass);
			$retval = $this->_instantiate_mixin($mixin_klass);
			$this->_cache_method($retval, $method);

		}

		return $retval;
	}


    /**
     * Provides an alternative way to call methods
     */
    function call_method($method, $args=array())
    {
        if (method_exists($this, $method))
        {
            $reflection = new ReflectionMethod($this, $method);
            return $reflection->invokeArgs($this, array($args));
        }
        else {
            return $this->__call($method, $args);
        }
    }


    /**
     * Returns TRUE if the method in particular has been cached
     * @param string $method
     * @return type
     */
    function is_cached($method)
    {
        return isset($this->_method_map_cache[$method]);
    }


    /**
     * Caches the path to the extension which provides a particular method
     * @param string $object
     * @param string $method
     */
    function _cache_method($object, $method)
    {
        $this->_method_map_cache[$method] = $object;
    }


	/**
	 * Gets a list of mixins by their priority, excluding disabled mixins
	 * @param string $method
	 * @return array
	 */
	function get_mixin_priorities($method)
	{
		$retval = array();
		foreach ($this->_mixin_priorities as $mixin) {
			if ($this->is_mixin_disabled($method, $mixin))
                continue;
			$retval[] = $mixin;
		}
		return $retval;
	}


	/**
	 * Determines if a mixin is disabled for a particular method
	 * @param string $method
	 * @param string $mixin
	 * @return boolean
	 */
	function is_mixin_disabled($method, $mixin)
	{
		$retval = FALSE;
		if (isset($this->_disabled_mixins[$method]))
			if (in_array($mixin, $this->_disabled_mixins[$method]) !== FALSE)
				$retval = TRUE;
		return $retval;
	}


    /**
     * Flushes the method cache
     */
    function _flush_cache()
    {
        $this->_method_map_cache = array();
    }


    /**
     * Returns TRUE if the object provides the particular method
     * @param string $method
     * @return boolean
     */
    function has_method($method)
    {
        $retval = FALSE;

        // Have we looked up this method before successfully?
        if ($this->is_cached($method)) {
            $retval = TRUE;
        }

        // Is this a local PHP method?
        elseif (method_exists($this, $method)) {
            $retval = TRUE;
        }

        // Is a mixin providing this method
        elseif ($this->get_mixin_providing($method)) {
            $retval = TRUE;
        }

        elseif ($this->is_wrapper() && $this->wrapped_class_provides($method)) {
            $retval = TRUE;
        }

        return $retval;
    }


    /**
     * Runs a particular pre hook for the specified method. The return value
     * is assigned to the "[hook_name]_prehook_retval" method property
     * @param string $hook_name
     * @param string $method_called
     * @param Ext $object
     * @param string $hook_method
     *
     */
    function _run_prehook($hook_name, $method_called, $object, $hook_method, &$args)
    {
        $object->object = &$this;
        $object->method_called = $method_called;

        // Are we STILL to execute pre hooks? A pre-executed hook might have changed this
        if ($this->get_method_property($method_called, 'run_pre_hooks'))
        {
            $reflection = new ReflectionMethod($object, $hook_method);
            $this->set_method_property(
                $method_called,
                $hook_name . '_prehook_retval',
                $reflection->invokeArgs($object, $args)
            );
        }
    }

    /**
     * Runs the specified post hook for the specified method
     * @param string $hook_name
     * @param string $method_called
     * @param Ext $object
     * @param string $hook_method
     */
    function _run_post_hook($hook_name, $method_called, $object, $hook_method, &$args)
    {
        $object->object = &$this;
        $object->method_called = $method_called;

        // Are we STILL to execute post hooks? A post-executed hook might have changed this
        if ($this->get_method_property($method_called, 'run_post_hooks'))
        {
            $reflection = new ReflectionMethod($object, $hook_method);
            $this->set_method_property(
                $method_called,
                $hook_name . '_post_hook_retval',
                $reflection->invokeArgs($object, $args)
            );
        }
    }

    /**
     * Returns TRUE if a pre-hook has been registered for the specified method
     * @param string $method
     * @return boolean
     */
    function have_prehook_for($method, $name = null)
    {
        if (is_null($name)) {
            return isset($this->_pre_hooks[$method]);
        } else {
            return isset($this->_pre_hooks[$method][$name]);
        }

    }


    /**
     * Returns TRUE if a posthook has been registered for the specified method
     * @param string $method
     * @return boolean
     */
    function have_posthook_for($method, $name = null)
    {
        $retval = FALSE;

        if (isset($this->_post_hooks[$method])) {
            if (!$name) $retval = TRUE;
            else $retval = isset($this->_post_hooks[$method][$name]);
        }

        return $retval;
    }

	/**
	 * Disables a mixin for a particular method. This ensures that even though
	 * mixin provides a particular method, it won't be used to provide the
	 * implementation
	 * @param string $method
	 * @param string $klass
	 */
	function disable_mixin($method, $klass)
	{
		unset($this->_method_map_cache[$method]);
		if (!isset($this->_disabled_mixins[$method])) {
			$this->_disabled_mixins[$method] = array();
		}
		$this->_disabled_mixins[$method][] = $klass;
	}


	/**
	 * Enable a mixin for a particular method, that was previously disabled
	 * @param string $method
	 * @param string $klass
	 */
	function enable_mixin($method, $klass)
	{
		unset($this->_method_map_cache[$method]);
		if (isset($this->_disabled_mixins[$method])) {
			$index = array_search($klass, $this->_disabled_mixins[$method]);
			if ($index !== FALSE) unset($this->_disabled_mixins[$method][$index]);
		}
	}


	/**
	 * Gets a list of mixins that are currently disabled for a particular method
	 * @see disable_mixin()
	 * @param string $method
	 * @return array
	 */
	function get_disabled_mixins_for($method)
	{
		$retval = array();
		if (isset($this->_disabled_mixins[$method])) {
			$retval =  $this->_disabled_mixins[$method];
		}
		return $retval;
	}


    /**
     * Executes a cached method
     * @param string $method
     * @param array $args
     * @return mixed
     */
    function _exec_cached_method($method, $args=array())
    {
        $object = $this->_method_map_cache[$method];
        $object->object = &$this;
        $reflection = new ReflectionMethod($object, $method);
        return $reflection->invokeArgs($object, $args);
    }


    /**
     * Sets the value of a method property
     * @param string $method
     * @param string $property
     * @param mixed $value
     */
    function set_method_property($method, $property, $value)
    {
        if (!isset($this->_method_properties[$method])) {
            $this->_method_properties[$method] = array();
        }

        return $this->_method_properties[$method][$property] = $value;
    }


    /**
     * Gets the value of a method property
     * @param string $method
     * @param string $property
     */
    function get_method_property($method, $property, $default=NULL)
    {
        $retval = NULL;

        if (isset($this->_method_properties[$method][$property])) {
            $retval = $this->_method_properties[$method][$property];
        }

		if (is_null($retval)) $retval=$default;

        return $retval;
    }


    /**
     * Clears all method properties to have their default values. This is called
     * before every method call (before pre-hooks)
     * @param string $method
     */
    function reset_method_properties($method, $args=array())
    {
        $this->_method_properties[$method] = array(
            'run'               => TRUE,
            'run_pre_hooks'     => TRUE,
            'run_post_hooks'    => TRUE,
			'arguments'			=> $args
        );
    }

	/**
	 * Removes the cache of the method properties
	 * @param $method
	 */
	function remove_method_properties($method)
	{
		unset($this->_method_properties[$method]);
	}

	/**
	 * Gets all method properties
	 * @return array
	 */
	function get_method_properties($method)
	{
		return $this->_method_properties[$method];
	}

	/**
	 * Sets all method properties
	 * @param $method
	 * @param $props
	 */
	function set_method_properties($method, $props)
	{
		foreach ($props as $key => $value) {
			$this->set_method_property($method, $key, $value);
		}
	}

    /**
     * Returns TRUE if the ExtensibleObject has decided to implement a
     * particular interface
     * @param string $interface
     * @return boolean
     */
    function implements_interface($interface)
    {
        return in_array($interface, $this->_interfaces);
    }

    function get_class_definition_dir($parent=FALSE)
    {
        return dirname($this->get_class_definition_file($parent));
    }

    function get_class_definition_file($parent=FALSE)
    {
		$klass = $this->get_class_name($this);
        $r = new ReflectionClass($klass);
        if ($parent) {
            $parent = $r->getParentClass();
            return $parent->getFileName();
        }
        return $r->getFileName();
    }

    /**
     * Returns get_class_methods() optionally limited by Mixin
     *
     * @param string (optional) Only show functions provided by a mixin
     * @return array Results from get_class_methods()
     */
    public function get_instance_methods($name = null)
    {
        if (is_string($name))
        {
            $methods = array();
            foreach ($this->_method_map_cache as $method => $mixin) {
                if ($name == get_class($mixin))
                {
                    $methods[] = $method;
                }
            }
            return $methods;
        } else {
            $methods = get_class_methods($this);
            foreach ($this->_mixins as $mixin) {
                $methods = array_unique(array_merge($methods, get_class_methods($mixin)));
                sort($methods);
            }

            return $methods;
        }
    }
}


/**
 * An mixin provides methods for an ExtensibleObject to use
 */
class Mixin extends PopeHelpers
{
    /**
     * The ExtensibleObject which called the extension's method
     * @var ExtensibleObject
     */
    var $object;

    /**
     * The name of the method called on the ExtensibleObject
     * @var type
     */
    var $method_called;

    /**
     * There really isn't any concept of 'parent' method. An ExtensibleObject
     * instance contains an ordered array of extension classes, which provides
     * the method implementations for the instance to use. Suppose that an
     * ExtensibleObject has two extension, and both have the same methods.The
     * last extension appears to 'override' the first extension. So, instead of calling
     * a 'parent' method, we're actually just calling an extension that was added sooner than
     * the one that is providing the current method implementation.
     */
    function call_parent($method)
    {
        $retval = NULL;

        // To simulate a 'parent' call, we remove the current extension from the
        // ExtensibleObject that is providing the method's implementation, re-emit
        // the call on the instance to trigger the implementation from the previously
        // added extension, and then restore things by re-adding the current extension.
        // It's complicated, but it works.

        // We need to determine the name of the extension. Because PHP 5.2 is
        // missing get_called_class(), we have to look it up in the backtrace
        $backtrace = debug_backtrace();
        $klass = get_class($backtrace[0]['object']);

		// Get the method properties. We'll store this afterwards.
		$props = $this->object->get_method_properties($method);

		// Perform the routine described above...
		$this->object->disable_pre_hooks($method);
		$this->object->disable_post_hooks($method);
		$this->object->disable_mixin($method, $klass);

        // Call anchor
        $args = func_get_args();

        // Remove $method parameter
        array_shift($args);
        $retval = $this->object->call_method($method, $args);

		// Re-enable hooks
		$this->object->enable_pre_hooks($method);
		$this->object->enable_post_hooks($method);
		$this->object->enable_mixin($method, $klass);

		// Re-set all method properties
		$this->object->set_method_properties($method, $props);

        return $retval;
    }

    /**
     * Although is is preferrable to call $this->object->method(), sometimes
     * it's nice to use $this->method() instead.
     * @param string $method
     * @param array $args
     * @return mixed
     */
    function __call($method, $args)
    {
        if ($this->object->has_method($method)) {
            return call_user_func_array(array(&$this->object, $method), $args);
        }
    }

    /**
     * Although extensions can have state, it's probably more desirable to maintain
     * the state in the parent object to keep a sane environment
     * @param string $property
     * @return mixed
     */
    function __get($property)
    {
        return $this->object->$property;
    }
}

/**
 * An extension which has the purpose of being used as a hook
 */
class Hook extends Mixin
{
    // Similiar to a mixin's call_parent method.
    // If a hook needs to call the method that it applied the
    // Hook n' Anchor pattern to, then this method should be called
    function call_anchor()
    {
		// Disable hooks, so that we call the anchor point
		$this->object->disable_pre_hooks($this->method_called);
		$this->object->disable_post_hooks($this->method_called);

        // Call anchor
        $args = func_get_args();
        $retval = $this->object->call_method($this->method_called, $args);

		// Re-enable hooks
		$this->object->enable_pre_hooks($this->method_called);
		$this->object->enable_post_hooks($this->method_called);

		return $retval;
    }

    /**
     * Provides an alias for call_anchor, as there's no parent
     * to call in the context of a hook.
     */
    function call_parent($method)
    {
        $args = func_get_args();
        return call_user_func_array(
            array(&$this, 'call_anchor'),
            $args
        );
    }
};
Back to Top