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
// This file is part of Substrate.

// Copyright (C) Parity Technologies (UK) Ltd.
// SPDX-License-Identifier: Apache-2.0

// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// 	http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

//! # Assets Pallet
//!
//! A simple, secure module for dealing with sets of assets implementing
//! [`fungible`](frame_support::traits::fungible) traits, via [`fungibles`] traits.
//!
//! The pallet makes heavy use of concepts such as Holds and Freezes from the
//! [`frame_support::traits::fungible`] traits, therefore you should read and understand those docs
//! as a prerequisite to understanding this pallet.
//!
//! See the [`frame_tokens`] reference docs for more information about the place of the
//! Assets pallet in FRAME.
//!
//! ## Overview
//!
//! The Assets module provides functionality for asset management of fungible asset classes
//! with a fixed supply, including:
//!
//! * Asset Issuance (Minting)
//! * Asset Transferal
//! * Asset Freezing
//! * Asset Destruction (Burning)
//! * Delegated Asset Transfers ("Approval API")
//!
//! To use it in your runtime, you need to implement the assets [`Config`].
//!
//! The supported dispatchable functions are documented in the [`Call`] enum.
//!
//! ### Terminology
//!
//! * **Admin**: An account ID uniquely privileged to be able to unfreeze (thaw) an account and its
//!   assets, as well as forcibly transfer a particular class of assets between arbitrary accounts
//!   and reduce the balance of a particular class of assets of arbitrary accounts.
//! * **Asset issuance/minting**: The creation of a new asset, whose total supply will belong to the
//!   account designated as the beneficiary of the asset. This is a privileged operation.
//! * **Asset transfer**: The reduction of the balance of an asset of one account with the
//!   corresponding increase in the balance of another.
//! * **Asset destruction**: The process of reducing the balance of an asset of one account. This is
//!   a privileged operation.
//! * **Fungible asset**: An asset whose units are interchangeable.
//! * **Issuer**: An account ID uniquely privileged to be able to mint a particular class of assets.
//! * **Freezer**: An account ID uniquely privileged to be able to freeze an account from
//!   transferring a particular class of assets.
//! * **Freezing**: Removing the possibility of an unpermissioned transfer of an asset from a
//!   particular account.
//! * **Non-fungible asset**: An asset for which each unit has unique characteristics.
//! * **Owner**: An account ID uniquely privileged to be able to destroy a particular asset class,
//!   or to set the Issuer, Freezer or Admin of that asset class.
//! * **Approval**: The act of allowing an account the permission to transfer some balance of asset
//!   from the approving account into some third-party destination account.
//! * **Sufficiency**: The idea of a minimum-balance of an asset being sufficient to allow the
//!   account's existence on the system without requiring any other existential-deposit.
//!
//! ### Goals
//!
//! The assets system in Substrate is designed to make the following possible:
//!
//! * Issue new assets in a permissioned or permissionless way, if permissionless, then with a
//!   deposit required.
//! * Allow accounts to be delegated the ability to transfer assets without otherwise existing
//!   on-chain (*approvals*).
//! * Move assets between accounts.
//! * Update an asset class's total supply.
//! * Allow administrative activities by specially privileged accounts including freezing account
//!   balances and minting/burning assets.
//!
//! ## Interface
//!
//! ### Permissionless Functions
//!
//! * `create`: Creates a new asset class, taking the required deposit.
//! * `transfer`: Transfer sender's assets to another account.
//! * `transfer_keep_alive`: Transfer sender's assets to another account, keeping the sender alive.
//! * `approve_transfer`: Create or increase an delegated transfer.
//! * `cancel_approval`: Rescind a previous approval.
//! * `transfer_approved`: Transfer third-party's assets to another account.
//! * `touch`: Create an asset account for non-provider assets. Caller must place a deposit.
//! * `refund`: Return the deposit (if any) of the caller's asset account or a consumer reference
//!   (if any) of the caller's account.
//! * `refund_other`: Return the deposit (if any) of a specified asset account.
//!
//! ### Permissioned Functions
//!
//! * `force_create`: Creates a new asset class without taking any deposit.
//! * `force_set_metadata`: Set the metadata of an asset class.
//! * `force_clear_metadata`: Remove the metadata of an asset class.
//! * `force_asset_status`: Alter an asset class's attributes.
//! * `force_cancel_approval`: Rescind a previous approval.
//!
//! ### Privileged Functions
//!
//! * `destroy`: Destroys an entire asset class; called by the asset class's Owner.
//! * `mint`: Increases the asset balance of an account; called by the asset class's Issuer.
//! * `burn`: Decreases the asset balance of an account; called by the asset class's Admin.
//! * `force_transfer`: Transfers between arbitrary accounts; called by the asset class's Admin.
//! * `freeze`: Disallows further `transfer`s from an account; called by the asset class's Freezer.
//! * `thaw`: Allows further `transfer`s to and from an account; called by the asset class's Admin.
//! * `transfer_ownership`: Changes an asset class's Owner; called by the asset class's Owner.
//! * `set_team`: Changes an asset class's Admin, Freezer and Issuer; called by the asset class's
//!   Owner.
//! * `set_metadata`: Set the metadata of an asset class; called by the asset class's Owner.
//! * `clear_metadata`: Remove the metadata of an asset class; called by the asset class's Owner.
//! * `touch_other`: Create an asset account for specified account. Caller must place a deposit;
//!   called by the asset class's Freezer or Admin.
//! * `block`: Disallows further `transfer`s to and from an account; called by the asset class's
//!   Freezer.
//!
//! Please refer to the [`Call`] enum and its associated variants for documentation on each
//! function.
//!
//! ### Public Functions
//! <!-- Original author of descriptions: @gavofyork -->
//!
//! * `balance` - Get the asset `id` balance of `who`.
//! * `total_supply` - Get the total supply of an asset `id`.
//!
//! Please refer to the [`Pallet`] struct for details on publicly available functions.
//!
//! ### Callbacks
//!
//! Using `CallbackHandle` associated type, user can configure custom callback functions which are
//! executed when new asset is created or an existing asset is destroyed.
//!
//! ## Related Modules
//!
//! * [`System`](../frame_system/index.html)
//! * [`Support`](../frame_support/index.html)
//!
//! [`frame_tokens`]: ../polkadot_sdk_docs/reference_docs/frame_tokens/index.html

// This recursion limit is needed because we have too many benchmarks and benchmarking will fail if
// we add more without this limit.
#![recursion_limit = "1024"]
// Ensure we're `no_std` when compiling for Wasm.
#![cfg_attr(not(feature = "std"), no_std)]

#[cfg(feature = "runtime-benchmarks")]
pub mod benchmarking;
pub mod migration;
#[cfg(test)]
pub mod mock;
#[cfg(test)]
mod tests;
pub mod weights;

mod extra_mutator;
pub use extra_mutator::*;
mod functions;
mod impl_fungibles;
mod impl_stored_map;
mod types;
pub use types::*;

extern crate alloc;

use scale_info::TypeInfo;
use sp_runtime::{
	traits::{AtLeast32BitUnsigned, CheckedAdd, CheckedSub, Saturating, StaticLookup, Zero},
	ArithmeticError, DispatchError, TokenError,
};

use alloc::vec::Vec;
use core::marker::PhantomData;
use frame_support::{
	dispatch::DispatchResult,
	ensure,
	pallet_prelude::DispatchResultWithPostInfo,
	storage::KeyPrefixIterator,
	traits::{
		tokens::{
			fungibles, DepositConsequence, Fortitude,
			Preservation::{Expendable, Preserve},
			WithdrawConsequence,
		},
		BalanceStatus::Reserved,
		Currency, EnsureOriginWithArg, Incrementable, ReservableCurrency, StoredMap,
	},
};
use frame_system::Config as SystemConfig;

pub use pallet::*;
pub use weights::WeightInfo;

type AccountIdLookupOf<T> = <<T as frame_system::Config>::Lookup as StaticLookup>::Source;
const LOG_TARGET: &str = "runtime::assets";

/// Trait with callbacks that are executed after successful asset creation or destruction.
pub trait AssetsCallback<AssetId, AccountId> {
	/// Indicates that asset with `id` was successfully created by the `owner`
	fn created(_id: &AssetId, _owner: &AccountId) -> Result<(), ()> {
		Ok(())
	}

	/// Indicates that asset with `id` has just been destroyed
	fn destroyed(_id: &AssetId) -> Result<(), ()> {
		Ok(())
	}
}

#[impl_trait_for_tuples::impl_for_tuples(10)]
impl<AssetId, AccountId> AssetsCallback<AssetId, AccountId> for Tuple {
	fn created(id: &AssetId, owner: &AccountId) -> Result<(), ()> {
		for_tuples!( #( Tuple::created(id, owner)?; )* );
		Ok(())
	}

	fn destroyed(id: &AssetId) -> Result<(), ()> {
		for_tuples!( #( Tuple::destroyed(id)?; )* );
		Ok(())
	}
}

/// Auto-increment the [`NextAssetId`] when an asset is created.
///
/// This has not effect if the [`NextAssetId`] value is not present.
pub struct AutoIncAssetId<T, I = ()>(PhantomData<(T, I)>);
impl<T: Config<I>, I> AssetsCallback<T::AssetId, T::AccountId> for AutoIncAssetId<T, I>
where
	T::AssetId: Incrementable,
{
	fn created(_: &T::AssetId, _: &T::AccountId) -> Result<(), ()> {
		let Some(next_id) = NextAssetId::<T, I>::get() else {
			// Auto increment for the asset id is not enabled.
			return Ok(());
		};
		let next_id = next_id.increment().ok_or(())?;
		NextAssetId::<T, I>::put(next_id);
		Ok(())
	}
}

#[frame_support::pallet]
pub mod pallet {
	use super::*;
	use frame_support::{
		pallet_prelude::*,
		traits::{AccountTouch, ContainsPair},
	};
	use frame_system::pallet_prelude::*;

	/// The in-code storage version.
	const STORAGE_VERSION: StorageVersion = StorageVersion::new(1);

	#[pallet::pallet]
	#[pallet::storage_version(STORAGE_VERSION)]
	pub struct Pallet<T, I = ()>(_);

	#[cfg(feature = "runtime-benchmarks")]
	pub trait BenchmarkHelper<AssetIdParameter> {
		fn create_asset_id_parameter(id: u32) -> AssetIdParameter;
	}
	#[cfg(feature = "runtime-benchmarks")]
	impl<AssetIdParameter: From<u32>> BenchmarkHelper<AssetIdParameter> for () {
		fn create_asset_id_parameter(id: u32) -> AssetIdParameter {
			id.into()
		}
	}

	/// Default implementations of [`DefaultConfig`], which can be used to implement [`Config`].
	pub mod config_preludes {
		use super::*;
		use frame_support::{derive_impl, traits::ConstU64};
		pub struct TestDefaultConfig;

		#[derive_impl(frame_system::config_preludes::TestDefaultConfig, no_aggregated_types)]
		impl frame_system::DefaultConfig for TestDefaultConfig {}

		#[frame_support::register_default_impl(TestDefaultConfig)]
		impl DefaultConfig for TestDefaultConfig {
			#[inject_runtime_type]
			type RuntimeEvent = ();
			type Balance = u64;
			type RemoveItemsLimit = ConstU32<5>;
			type AssetId = u32;
			type AssetIdParameter = u32;
			type AssetDeposit = ConstU64<1>;
			type AssetAccountDeposit = ConstU64<10>;
			type MetadataDepositBase = ConstU64<1>;
			type MetadataDepositPerByte = ConstU64<1>;
			type ApprovalDeposit = ConstU64<1>;
			type StringLimit = ConstU32<50>;
			type Extra = ();
			type CallbackHandle = ();
			type WeightInfo = ();
			#[cfg(feature = "runtime-benchmarks")]
			type BenchmarkHelper = ();
		}
	}

	#[pallet::config(with_default)]
	/// The module configuration trait.
	pub trait Config<I: 'static = ()>: frame_system::Config {
		/// The overarching event type.
		#[pallet::no_default_bounds]
		type RuntimeEvent: From<Event<Self, I>>
			+ IsType<<Self as frame_system::Config>::RuntimeEvent>;

		/// The units in which we record balances.
		type Balance: Member
			+ Parameter
			+ AtLeast32BitUnsigned
			+ Default
			+ Copy
			+ MaybeSerializeDeserialize
			+ MaxEncodedLen
			+ TypeInfo;

		/// Max number of items to destroy per `destroy_accounts` and `destroy_approvals` call.
		///
		/// Must be configured to result in a weight that makes each call fit in a block.
		#[pallet::constant]
		type RemoveItemsLimit: Get<u32>;

		/// Identifier for the class of asset.
		type AssetId: Member + Parameter + Clone + MaybeSerializeDeserialize + MaxEncodedLen;

		/// Wrapper around `Self::AssetId` to use in dispatchable call signatures. Allows the use
		/// of compact encoding in instances of the pallet, which will prevent breaking changes
		/// resulting from the removal of `HasCompact` from `Self::AssetId`.
		///
		/// This type includes the `From<Self::AssetId>` bound, since tightly coupled pallets may
		/// want to convert an `AssetId` into a parameter for calling dispatchable functions
		/// directly.
		type AssetIdParameter: Parameter + From<Self::AssetId> + Into<Self::AssetId> + MaxEncodedLen;

		/// The currency mechanism.
		#[pallet::no_default]
		type Currency: ReservableCurrency<Self::AccountId>;

		/// Standard asset class creation is only allowed if the origin attempting it and the
		/// asset class are in this set.
		#[pallet::no_default]
		type CreateOrigin: EnsureOriginWithArg<
			Self::RuntimeOrigin,
			Self::AssetId,
			Success = Self::AccountId,
		>;

		/// The origin which may forcibly create or destroy an asset or otherwise alter privileged
		/// attributes.
		#[pallet::no_default]
		type ForceOrigin: EnsureOrigin<Self::RuntimeOrigin>;

		/// The basic amount of funds that must be reserved for an asset.
		#[pallet::constant]
		#[pallet::no_default_bounds]
		type AssetDeposit: Get<DepositBalanceOf<Self, I>>;

		/// The amount of funds that must be reserved for a non-provider asset account to be
		/// maintained.
		#[pallet::constant]
		#[pallet::no_default_bounds]
		type AssetAccountDeposit: Get<DepositBalanceOf<Self, I>>;

		/// The basic amount of funds that must be reserved when adding metadata to your asset.
		#[pallet::constant]
		#[pallet::no_default_bounds]
		type MetadataDepositBase: Get<DepositBalanceOf<Self, I>>;

		/// The additional funds that must be reserved for the number of bytes you store in your
		/// metadata.
		#[pallet::constant]
		#[pallet::no_default_bounds]
		type MetadataDepositPerByte: Get<DepositBalanceOf<Self, I>>;

		/// The amount of funds that must be reserved when creating a new approval.
		#[pallet::constant]
		#[pallet::no_default_bounds]
		type ApprovalDeposit: Get<DepositBalanceOf<Self, I>>;

		/// The maximum length of a name or symbol stored on-chain.
		#[pallet::constant]
		type StringLimit: Get<u32>;

		/// A hook to allow a per-asset, per-account minimum balance to be enforced. This must be
		/// respected in all permissionless operations.
		#[pallet::no_default]
		type Freezer: FrozenBalance<Self::AssetId, Self::AccountId, Self::Balance>;

		/// Additional data to be stored with an account's asset balance.
		type Extra: Member + Parameter + Default + MaxEncodedLen;

		/// Callback methods for asset state change (e.g. asset created or destroyed)
		///
		/// Types implementing the [`AssetsCallback`] can be chained when listed together as a
		/// tuple.
		/// The [`AutoIncAssetId`] callback, in conjunction with the [`NextAssetId`], can be
		/// used to set up auto-incrementing asset IDs for this collection.
		type CallbackHandle: AssetsCallback<Self::AssetId, Self::AccountId>;

		/// Weight information for extrinsics in this pallet.
		type WeightInfo: WeightInfo;

		/// Helper trait for benchmarks.
		#[cfg(feature = "runtime-benchmarks")]
		type BenchmarkHelper: BenchmarkHelper<Self::AssetIdParameter>;
	}

	#[pallet::storage]
	/// Details of an asset.
	pub(super) type Asset<T: Config<I>, I: 'static = ()> = StorageMap<
		_,
		Blake2_128Concat,
		T::AssetId,
		AssetDetails<T::Balance, T::AccountId, DepositBalanceOf<T, I>>,
	>;

	#[pallet::storage]
	/// The holdings of a specific account for a specific asset.
	pub(super) type Account<T: Config<I>, I: 'static = ()> = StorageDoubleMap<
		_,
		Blake2_128Concat,
		T::AssetId,
		Blake2_128Concat,
		T::AccountId,
		AssetAccountOf<T, I>,
	>;

	#[pallet::storage]
	/// Approved balance transfers. First balance is the amount approved for transfer. Second
	/// is the amount of `T::Currency` reserved for storing this.
	/// First key is the asset ID, second key is the owner and third key is the delegate.
	pub(super) type Approvals<T: Config<I>, I: 'static = ()> = StorageNMap<
		_,
		(
			NMapKey<Blake2_128Concat, T::AssetId>,
			NMapKey<Blake2_128Concat, T::AccountId>, // owner
			NMapKey<Blake2_128Concat, T::AccountId>, // delegate
		),
		Approval<T::Balance, DepositBalanceOf<T, I>>,
	>;

	#[pallet::storage]
	/// Metadata of an asset.
	pub(super) type Metadata<T: Config<I>, I: 'static = ()> = StorageMap<
		_,
		Blake2_128Concat,
		T::AssetId,
		AssetMetadata<DepositBalanceOf<T, I>, BoundedVec<u8, T::StringLimit>>,
		ValueQuery,
	>;

	/// The asset ID enforced for the next asset creation, if any present. Otherwise, this storage
	/// item has no effect.
	///
	/// This can be useful for setting up constraints for IDs of the new assets. For example, by
	/// providing an initial [`NextAssetId`] and using the [`crate::AutoIncAssetId`] callback, an
	/// auto-increment model can be applied to all new asset IDs.
	///
	/// The initial next asset ID can be set using the [`GenesisConfig`] or the
	/// [SetNextAssetId](`migration::next_asset_id::SetNextAssetId`) migration.
	#[pallet::storage]
	pub type NextAssetId<T: Config<I>, I: 'static = ()> = StorageValue<_, T::AssetId, OptionQuery>;

	#[pallet::genesis_config]
	#[derive(frame_support::DefaultNoBound)]
	pub struct GenesisConfig<T: Config<I>, I: 'static = ()> {
		/// Genesis assets: id, owner, is_sufficient, min_balance
		pub assets: Vec<(T::AssetId, T::AccountId, bool, T::Balance)>,
		/// Genesis metadata: id, name, symbol, decimals
		pub metadata: Vec<(T::AssetId, Vec<u8>, Vec<u8>, u8)>,
		/// Genesis accounts: id, account_id, balance
		pub accounts: Vec<(T::AssetId, T::AccountId, T::Balance)>,
		/// Genesis [`NextAssetId`].
		///
		/// Refer to the [`NextAssetId`] item for more information.
		///
		/// This does not enforce the asset ID for the [assets](`GenesisConfig::assets`) within the
		/// genesis config. It sets the [`NextAssetId`] after they have been created.
		pub next_asset_id: Option<T::AssetId>,
	}

	#[pallet::genesis_build]
	impl<T: Config<I>, I: 'static> BuildGenesisConfig for GenesisConfig<T, I> {
		fn build(&self) {
			for (id, owner, is_sufficient, min_balance) in &self.assets {
				assert!(!Asset::<T, I>::contains_key(id), "Asset id already in use");
				assert!(!min_balance.is_zero(), "Min balance should not be zero");
				Asset::<T, I>::insert(
					id,
					AssetDetails {
						owner: owner.clone(),
						issuer: owner.clone(),
						admin: owner.clone(),
						freezer: owner.clone(),
						supply: Zero::zero(),
						deposit: Zero::zero(),
						min_balance: *min_balance,
						is_sufficient: *is_sufficient,
						accounts: 0,
						sufficients: 0,
						approvals: 0,
						status: AssetStatus::Live,
					},
				);
			}

			for (id, name, symbol, decimals) in &self.metadata {
				assert!(Asset::<T, I>::contains_key(id), "Asset does not exist");

				let bounded_name: BoundedVec<u8, T::StringLimit> =
					name.clone().try_into().expect("asset name is too long");
				let bounded_symbol: BoundedVec<u8, T::StringLimit> =
					symbol.clone().try_into().expect("asset symbol is too long");

				let metadata = AssetMetadata {
					deposit: Zero::zero(),
					name: bounded_name,
					symbol: bounded_symbol,
					decimals: *decimals,
					is_frozen: false,
				};
				Metadata::<T, I>::insert(id, metadata);
			}

			for (id, account_id, amount) in &self.accounts {
				let result = <Pallet<T, I>>::increase_balance(
					id.clone(),
					account_id,
					*amount,
					|details| -> DispatchResult {
						debug_assert!(
							details.supply.checked_add(&amount).is_some(),
							"checked in prep; qed"
						);
						details.supply = details.supply.saturating_add(*amount);
						Ok(())
					},
				);
				assert!(result.is_ok());
			}

			if let Some(next_asset_id) = &self.next_asset_id {
				NextAssetId::<T, I>::put(next_asset_id);
			}
		}
	}

	#[pallet::event]
	#[pallet::generate_deposit(pub(super) fn deposit_event)]
	pub enum Event<T: Config<I>, I: 'static = ()> {
		/// Some asset class was created.
		Created { asset_id: T::AssetId, creator: T::AccountId, owner: T::AccountId },
		/// Some assets were issued.
		Issued { asset_id: T::AssetId, owner: T::AccountId, amount: T::Balance },
		/// Some assets were transferred.
		Transferred {
			asset_id: T::AssetId,
			from: T::AccountId,
			to: T::AccountId,
			amount: T::Balance,
		},
		/// Some assets were destroyed.
		Burned { asset_id: T::AssetId, owner: T::AccountId, balance: T::Balance },
		/// The management team changed.
		TeamChanged {
			asset_id: T::AssetId,
			issuer: T::AccountId,
			admin: T::AccountId,
			freezer: T::AccountId,
		},
		/// The owner changed.
		OwnerChanged { asset_id: T::AssetId, owner: T::AccountId },
		/// Some account `who` was frozen.
		Frozen { asset_id: T::AssetId, who: T::AccountId },
		/// Some account `who` was thawed.
		Thawed { asset_id: T::AssetId, who: T::AccountId },
		/// Some asset `asset_id` was frozen.
		AssetFrozen { asset_id: T::AssetId },
		/// Some asset `asset_id` was thawed.
		AssetThawed { asset_id: T::AssetId },
		/// Accounts were destroyed for given asset.
		AccountsDestroyed { asset_id: T::AssetId, accounts_destroyed: u32, accounts_remaining: u32 },
		/// Approvals were destroyed for given asset.
		ApprovalsDestroyed {
			asset_id: T::AssetId,
			approvals_destroyed: u32,
			approvals_remaining: u32,
		},
		/// An asset class is in the process of being destroyed.
		DestructionStarted { asset_id: T::AssetId },
		/// An asset class was destroyed.
		Destroyed { asset_id: T::AssetId },
		/// Some asset class was force-created.
		ForceCreated { asset_id: T::AssetId, owner: T::AccountId },
		/// New metadata has been set for an asset.
		MetadataSet {
			asset_id: T::AssetId,
			name: Vec<u8>,
			symbol: Vec<u8>,
			decimals: u8,
			is_frozen: bool,
		},
		/// Metadata has been cleared for an asset.
		MetadataCleared { asset_id: T::AssetId },
		/// (Additional) funds have been approved for transfer to a destination account.
		ApprovedTransfer {
			asset_id: T::AssetId,
			source: T::AccountId,
			delegate: T::AccountId,
			amount: T::Balance,
		},
		/// An approval for account `delegate` was cancelled by `owner`.
		ApprovalCancelled { asset_id: T::AssetId, owner: T::AccountId, delegate: T::AccountId },
		/// An `amount` was transferred in its entirety from `owner` to `destination` by
		/// the approved `delegate`.
		TransferredApproved {
			asset_id: T::AssetId,
			owner: T::AccountId,
			delegate: T::AccountId,
			destination: T::AccountId,
			amount: T::Balance,
		},
		/// An asset has had its attributes changed by the `Force` origin.
		AssetStatusChanged { asset_id: T::AssetId },
		/// The min_balance of an asset has been updated by the asset owner.
		AssetMinBalanceChanged { asset_id: T::AssetId, new_min_balance: T::Balance },
		/// Some account `who` was created with a deposit from `depositor`.
		Touched { asset_id: T::AssetId, who: T::AccountId, depositor: T::AccountId },
		/// Some account `who` was blocked.
		Blocked { asset_id: T::AssetId, who: T::AccountId },
		/// Some assets were deposited (e.g. for transaction fees).
		Deposited { asset_id: T::AssetId, who: T::AccountId, amount: T::Balance },
		/// Some assets were withdrawn from the account (e.g. for transaction fees).
		Withdrawn { asset_id: T::AssetId, who: T::AccountId, amount: T::Balance },
	}

	#[pallet::error]
	pub enum Error<T, I = ()> {
		/// Account balance must be greater than or equal to the transfer amount.
		BalanceLow,
		/// The account to alter does not exist.
		NoAccount,
		/// The signing account has no permission to do the operation.
		NoPermission,
		/// The given asset ID is unknown.
		Unknown,
		/// The origin account is frozen.
		Frozen,
		/// The asset ID is already taken.
		InUse,
		/// Invalid witness data given.
		BadWitness,
		/// Minimum balance should be non-zero.
		MinBalanceZero,
		/// Unable to increment the consumer reference counters on the account. Either no provider
		/// reference exists to allow a non-zero balance of a non-self-sufficient asset, or one
		/// fewer then the maximum number of consumers has been reached.
		UnavailableConsumer,
		/// Invalid metadata given.
		BadMetadata,
		/// No approval exists that would allow the transfer.
		Unapproved,
		/// The source account would not survive the transfer and it needs to stay alive.
		WouldDie,
		/// The asset-account already exists.
		AlreadyExists,
		/// The asset-account doesn't have an associated deposit.
		NoDeposit,
		/// The operation would result in funds being burned.
		WouldBurn,
		/// The asset is a live asset and is actively being used. Usually emit for operations such
		/// as `start_destroy` which require the asset to be in a destroying state.
		LiveAsset,
		/// The asset is not live, and likely being destroyed.
		AssetNotLive,
		/// The asset status is not the expected status.
		IncorrectStatus,
		/// The asset should be frozen before the given operation.
		NotFrozen,
		/// Callback action resulted in error
		CallbackFailed,
		/// The asset ID must be equal to the [`NextAssetId`].
		BadAssetId,
	}

	#[pallet::call(weight(<T as Config<I>>::WeightInfo))]
	impl<T: Config<I>, I: 'static> Pallet<T, I> {
		/// Issue a new class of fungible assets from a public origin.
		///
		/// This new asset class has no assets initially and its owner is the origin.
		///
		/// The origin must conform to the configured `CreateOrigin` and have sufficient funds free.
		///
		/// Funds of sender are reserved by `AssetDeposit`.
		///
		/// Parameters:
		/// - `id`: The identifier of the new asset. This must not be currently in use to identify
		/// an existing asset. If [`NextAssetId`] is set, then this must be equal to it.
		/// - `admin`: The admin of this class of assets. The admin is the initial address of each
		/// member of the asset class's admin team.
		/// - `min_balance`: The minimum balance of this new asset that any single account must
		/// have. If an account's balance is reduced below this, then it collapses to zero.
		///
		/// Emits `Created` event when successful.
		///
		/// Weight: `O(1)`
		#[pallet::call_index(0)]
		pub fn create(
			origin: OriginFor<T>,
			id: T::AssetIdParameter,
			admin: AccountIdLookupOf<T>,
			min_balance: T::Balance,
		) -> DispatchResult {
			let id: T::AssetId = id.into();
			let owner = T::CreateOrigin::ensure_origin(origin, &id)?;
			let admin = T::Lookup::lookup(admin)?;

			ensure!(!Asset::<T, I>::contains_key(&id), Error::<T, I>::InUse);
			ensure!(!min_balance.is_zero(), Error::<T, I>::MinBalanceZero);

			if let Some(next_id) = NextAssetId::<T, I>::get() {
				ensure!(id == next_id, Error::<T, I>::BadAssetId);
			}

			let deposit = T::AssetDeposit::get();
			T::Currency::reserve(&owner, deposit)?;

			Asset::<T, I>::insert(
				id.clone(),
				AssetDetails {
					owner: owner.clone(),
					issuer: admin.clone(),
					admin: admin.clone(),
					freezer: admin.clone(),
					supply: Zero::zero(),
					deposit,
					min_balance,
					is_sufficient: false,
					accounts: 0,
					sufficients: 0,
					approvals: 0,
					status: AssetStatus::Live,
				},
			);
			ensure!(T::CallbackHandle::created(&id, &owner).is_ok(), Error::<T, I>::CallbackFailed);
			Self::deposit_event(Event::Created {
				asset_id: id,
				creator: owner.clone(),
				owner: admin,
			});

			Ok(())
		}

		/// Issue a new class of fungible assets from a privileged origin.
		///
		/// This new asset class has no assets initially.
		///
		/// The origin must conform to `ForceOrigin`.
		///
		/// Unlike `create`, no funds are reserved.
		///
		/// - `id`: The identifier of the new asset. This must not be currently in use to identify
		/// an existing asset. If [`NextAssetId`] is set, then this must be equal to it.
		/// - `owner`: The owner of this class of assets. The owner has full superuser permissions
		/// over this asset, but may later change and configure the permissions using
		/// `transfer_ownership` and `set_team`.
		/// - `min_balance`: The minimum balance of this new asset that any single account must
		/// have. If an account's balance is reduced below this, then it collapses to zero.
		///
		/// Emits `ForceCreated` event when successful.
		///
		/// Weight: `O(1)`
		#[pallet::call_index(1)]
		pub fn force_create(
			origin: OriginFor<T>,
			id: T::AssetIdParameter,
			owner: AccountIdLookupOf<T>,
			is_sufficient: bool,
			#[pallet::compact] min_balance: T::Balance,
		) -> DispatchResult {
			T::ForceOrigin::ensure_origin(origin)?;
			let owner = T::Lookup::lookup(owner)?;
			let id: T::AssetId = id.into();
			Self::do_force_create(id, owner, is_sufficient, min_balance)
		}

		/// Start the process of destroying a fungible asset class.
		///
		/// `start_destroy` is the first in a series of extrinsics that should be called, to allow
		/// destruction of an asset class.
		///
		/// The origin must conform to `ForceOrigin` or must be `Signed` by the asset's `owner`.
		///
		/// - `id`: The identifier of the asset to be destroyed. This must identify an existing
		///   asset.
		#[pallet::call_index(2)]
		pub fn start_destroy(origin: OriginFor<T>, id: T::AssetIdParameter) -> DispatchResult {
			let maybe_check_owner = match T::ForceOrigin::try_origin(origin) {
				Ok(_) => None,
				Err(origin) => Some(ensure_signed(origin)?),
			};
			let id: T::AssetId = id.into();
			Self::do_start_destroy(id, maybe_check_owner)
		}

		/// Destroy all accounts associated with a given asset.
		///
		/// `destroy_accounts` should only be called after `start_destroy` has been called, and the
		/// asset is in a `Destroying` state.
		///
		/// Due to weight restrictions, this function may need to be called multiple times to fully
		/// destroy all accounts. It will destroy `RemoveItemsLimit` accounts at a time.
		///
		/// - `id`: The identifier of the asset to be destroyed. This must identify an existing
		///   asset.
		///
		/// Each call emits the `Event::DestroyedAccounts` event.
		#[pallet::call_index(3)]
		#[pallet::weight(T::WeightInfo::destroy_accounts(T::RemoveItemsLimit::get()))]
		pub fn destroy_accounts(
			origin: OriginFor<T>,
			id: T::AssetIdParameter,
		) -> DispatchResultWithPostInfo {
			let _ = ensure_signed(origin)?;
			let id: T::AssetId = id.into();
			let removed_accounts = Self::do_destroy_accounts(id, T::RemoveItemsLimit::get())?;
			Ok(Some(T::WeightInfo::destroy_accounts(removed_accounts)).into())
		}

		/// Destroy all approvals associated with a given asset up to the max (T::RemoveItemsLimit).
		///
		/// `destroy_approvals` should only be called after `start_destroy` has been called, and the
		/// asset is in a `Destroying` state.
		///
		/// Due to weight restrictions, this function may need to be called multiple times to fully
		/// destroy all approvals. It will destroy `RemoveItemsLimit` approvals at a time.
		///
		/// - `id`: The identifier of the asset to be destroyed. This must identify an existing
		///   asset.
		///
		/// Each call emits the `Event::DestroyedApprovals` event.
		#[pallet::call_index(4)]
		#[pallet::weight(T::WeightInfo::destroy_approvals(T::RemoveItemsLimit::get()))]
		pub fn destroy_approvals(
			origin: OriginFor<T>,
			id: T::AssetIdParameter,
		) -> DispatchResultWithPostInfo {
			let _ = ensure_signed(origin)?;
			let id: T::AssetId = id.into();
			let removed_approvals = Self::do_destroy_approvals(id, T::RemoveItemsLimit::get())?;
			Ok(Some(T::WeightInfo::destroy_approvals(removed_approvals)).into())
		}

		/// Complete destroying asset and unreserve currency.
		///
		/// `finish_destroy` should only be called after `start_destroy` has been called, and the
		/// asset is in a `Destroying` state. All accounts or approvals should be destroyed before
		/// hand.
		///
		/// - `id`: The identifier of the asset to be destroyed. This must identify an existing
		///   asset.
		///
		/// Each successful call emits the `Event::Destroyed` event.
		#[pallet::call_index(5)]
		pub fn finish_destroy(origin: OriginFor<T>, id: T::AssetIdParameter) -> DispatchResult {
			let _ = ensure_signed(origin)?;
			let id: T::AssetId = id.into();
			Self::do_finish_destroy(id)
		}

		/// Mint assets of a particular class.
		///
		/// The origin must be Signed and the sender must be the Issuer of the asset `id`.
		///
		/// - `id`: The identifier of the asset to have some amount minted.
		/// - `beneficiary`: The account to be credited with the minted assets.
		/// - `amount`: The amount of the asset to be minted.
		///
		/// Emits `Issued` event when successful.
		///
		/// Weight: `O(1)`
		/// Modes: Pre-existing balance of `beneficiary`; Account pre-existence of `beneficiary`.
		#[pallet::call_index(6)]
		pub fn mint(
			origin: OriginFor<T>,
			id: T::AssetIdParameter,
			beneficiary: AccountIdLookupOf<T>,
			#[pallet::compact] amount: T::Balance,
		) -> DispatchResult {
			let origin = ensure_signed(origin)?;
			let beneficiary = T::Lookup::lookup(beneficiary)?;
			let id: T::AssetId = id.into();
			Self::do_mint(id, &beneficiary, amount, Some(origin))?;
			Ok(())
		}

		/// Reduce the balance of `who` by as much as possible up to `amount` assets of `id`.
		///
		/// Origin must be Signed and the sender should be the Manager of the asset `id`.
		///
		/// Bails with `NoAccount` if the `who` is already dead.
		///
		/// - `id`: The identifier of the asset to have some amount burned.
		/// - `who`: The account to be debited from.
		/// - `amount`: The maximum amount by which `who`'s balance should be reduced.
		///
		/// Emits `Burned` with the actual amount burned. If this takes the balance to below the
		/// minimum for the asset, then the amount burned is increased to take it to zero.
		///
		/// Weight: `O(1)`
		/// Modes: Post-existence of `who`; Pre & post Zombie-status of `who`.
		#[pallet::call_index(7)]
		pub fn burn(
			origin: OriginFor<T>,
			id: T::AssetIdParameter,
			who: AccountIdLookupOf<T>,
			#[pallet::compact] amount: T::Balance,
		) -> DispatchResult {
			let origin = ensure_signed(origin)?;
			let who = T::Lookup::lookup(who)?;
			let id: T::AssetId = id.into();

			let f = DebitFlags { keep_alive: false, best_effort: true };
			let _ = Self::do_burn(id, &who, amount, Some(origin), f)?;
			Ok(())
		}

		/// Move some assets from the sender account to another.
		///
		/// Origin must be Signed.
		///
		/// - `id`: The identifier of the asset to have some amount transferred.
		/// - `target`: The account to be credited.
		/// - `amount`: The amount by which the sender's balance of assets should be reduced and
		/// `target`'s balance increased. The amount actually transferred may be slightly greater in
		/// the case that the transfer would otherwise take the sender balance above zero but below
		/// the minimum balance. Must be greater than zero.
		///
		/// Emits `Transferred` with the actual amount transferred. If this takes the source balance
		/// to below the minimum for the asset, then the amount transferred is increased to take it
		/// to zero.
		///
		/// Weight: `O(1)`
		/// Modes: Pre-existence of `target`; Post-existence of sender; Account pre-existence of
		/// `target`.
		#[pallet::call_index(8)]
		pub fn transfer(
			origin: OriginFor<T>,
			id: T::AssetIdParameter,
			target: AccountIdLookupOf<T>,
			#[pallet::compact] amount: T::Balance,
		) -> DispatchResult {
			let origin = ensure_signed(origin)?;
			let dest = T::Lookup::lookup(target)?;
			let id: T::AssetId = id.into();

			let f = TransferFlags { keep_alive: false, best_effort: false, burn_dust: false };
			Self::do_transfer(id, &origin, &dest, amount, None, f).map(|_| ())
		}

		/// Move some assets from the sender account to another, keeping the sender account alive.
		///
		/// Origin must be Signed.
		///
		/// - `id`: The identifier of the asset to have some amount transferred.
		/// - `target`: The account to be credited.
		/// - `amount`: The amount by which the sender's balance of assets should be reduced and
		/// `target`'s balance increased. The amount actually transferred may be slightly greater in
		/// the case that the transfer would otherwise take the sender balance above zero but below
		/// the minimum balance. Must be greater than zero.
		///
		/// Emits `Transferred` with the actual amount transferred. If this takes the source balance
		/// to below the minimum for the asset, then the amount transferred is increased to take it
		/// to zero.
		///
		/// Weight: `O(1)`
		/// Modes: Pre-existence of `target`; Post-existence of sender; Account pre-existence of
		/// `target`.
		#[pallet::call_index(9)]
		pub fn transfer_keep_alive(
			origin: OriginFor<T>,
			id: T::AssetIdParameter,
			target: AccountIdLookupOf<T>,
			#[pallet::compact] amount: T::Balance,
		) -> DispatchResult {
			let source = ensure_signed(origin)?;
			let dest = T::Lookup::lookup(target)?;
			let id: T::AssetId = id.into();

			let f = TransferFlags { keep_alive: true, best_effort: false, burn_dust: false };
			Self::do_transfer(id, &source, &dest, amount, None, f).map(|_| ())
		}

		/// Move some assets from one account to another.
		///
		/// Origin must be Signed and the sender should be the Admin of the asset `id`.
		///
		/// - `id`: The identifier of the asset to have some amount transferred.
		/// - `source`: The account to be debited.
		/// - `dest`: The account to be credited.
		/// - `amount`: The amount by which the `source`'s balance of assets should be reduced and
		/// `dest`'s balance increased. The amount actually transferred may be slightly greater in
		/// the case that the transfer would otherwise take the `source` balance above zero but
		/// below the minimum balance. Must be greater than zero.
		///
		/// Emits `Transferred` with the actual amount transferred. If this takes the source balance
		/// to below the minimum for the asset, then the amount transferred is increased to take it
		/// to zero.
		///
		/// Weight: `O(1)`
		/// Modes: Pre-existence of `dest`; Post-existence of `source`; Account pre-existence of
		/// `dest`.
		#[pallet::call_index(10)]
		pub fn force_transfer(
			origin: OriginFor<T>,
			id: T::AssetIdParameter,
			source: AccountIdLookupOf<T>,
			dest: AccountIdLookupOf<T>,
			#[pallet::compact] amount: T::Balance,
		) -> DispatchResult {
			let origin = ensure_signed(origin)?;
			let source = T::Lookup::lookup(source)?;
			let dest = T::Lookup::lookup(dest)?;
			let id: T::AssetId = id.into();

			let f = TransferFlags { keep_alive: false, best_effort: false, burn_dust: false };
			Self::do_transfer(id, &source, &dest, amount, Some(origin), f).map(|_| ())
		}

		/// Disallow further unprivileged transfers of an asset `id` from an account `who`. `who`
		/// must already exist as an entry in `Account`s of the asset. If you want to freeze an
		/// account that does not have an entry, use `touch_other` first.
		///
		/// Origin must be Signed and the sender should be the Freezer of the asset `id`.
		///
		/// - `id`: The identifier of the asset to be frozen.
		/// - `who`: The account to be frozen.
		///
		/// Emits `Frozen`.
		///
		/// Weight: `O(1)`
		#[pallet::call_index(11)]
		pub fn freeze(
			origin: OriginFor<T>,
			id: T::AssetIdParameter,
			who: AccountIdLookupOf<T>,
		) -> DispatchResult {
			let origin = ensure_signed(origin)?;
			let id: T::AssetId = id.into();

			let d = Asset::<T, I>::get(&id).ok_or(Error::<T, I>::Unknown)?;
			ensure!(
				d.status == AssetStatus::Live || d.status == AssetStatus::Frozen,
				Error::<T, I>::IncorrectStatus
			);
			ensure!(origin == d.freezer, Error::<T, I>::NoPermission);
			let who = T::Lookup::lookup(who)?;

			Account::<T, I>::try_mutate(&id, &who, |maybe_account| -> DispatchResult {
				maybe_account.as_mut().ok_or(Error::<T, I>::NoAccount)?.status =
					AccountStatus::Frozen;
				Ok(())
			})?;

			Self::deposit_event(Event::<T, I>::Frozen { asset_id: id, who });
			Ok(())
		}

		/// Allow unprivileged transfers to and from an account again.
		///
		/// Origin must be Signed and the sender should be the Admin of the asset `id`.
		///
		/// - `id`: The identifier of the asset to be frozen.
		/// - `who`: The account to be unfrozen.
		///
		/// Emits `Thawed`.
		///
		/// Weight: `O(1)`
		#[pallet::call_index(12)]
		pub fn thaw(
			origin: OriginFor<T>,
			id: T::AssetIdParameter,
			who: AccountIdLookupOf<T>,
		) -> DispatchResult {
			let origin = ensure_signed(origin)?;
			let id: T::AssetId = id.into();

			let details = Asset::<T, I>::get(&id).ok_or(Error::<T, I>::Unknown)?;
			ensure!(
				details.status == AssetStatus::Live || details.status == AssetStatus::Frozen,
				Error::<T, I>::IncorrectStatus
			);
			ensure!(origin == details.admin, Error::<T, I>::NoPermission);
			let who = T::Lookup::lookup(who)?;

			Account::<T, I>::try_mutate(&id, &who, |maybe_account| -> DispatchResult {
				maybe_account.as_mut().ok_or(Error::<T, I>::NoAccount)?.status =
					AccountStatus::Liquid;
				Ok(())
			})?;

			Self::deposit_event(Event::<T, I>::Thawed { asset_id: id, who });
			Ok(())
		}

		/// Disallow further unprivileged transfers for the asset class.
		///
		/// Origin must be Signed and the sender should be the Freezer of the asset `id`.
		///
		/// - `id`: The identifier of the asset to be frozen.
		///
		/// Emits `Frozen`.
		///
		/// Weight: `O(1)`
		#[pallet::call_index(13)]
		pub fn freeze_asset(origin: OriginFor<T>, id: T::AssetIdParameter) -> DispatchResult {
			let origin = ensure_signed(origin)?;
			let id: T::AssetId = id.into();

			Asset::<T, I>::try_mutate(id.clone(), |maybe_details| {
				let d = maybe_details.as_mut().ok_or(Error::<T, I>::Unknown)?;
				ensure!(d.status == AssetStatus::Live, Error::<T, I>::AssetNotLive);
				ensure!(origin == d.freezer, Error::<T, I>::NoPermission);

				d.status = AssetStatus::Frozen;

				Self::deposit_event(Event::<T, I>::AssetFrozen { asset_id: id });
				Ok(())
			})
		}

		/// Allow unprivileged transfers for the asset again.
		///
		/// Origin must be Signed and the sender should be the Admin of the asset `id`.
		///
		/// - `id`: The identifier of the asset to be thawed.
		///
		/// Emits `Thawed`.
		///
		/// Weight: `O(1)`
		#[pallet::call_index(14)]
		pub fn thaw_asset(origin: OriginFor<T>, id: T::AssetIdParameter) -> DispatchResult {
			let origin = ensure_signed(origin)?;
			let id: T::AssetId = id.into();

			Asset::<T, I>::try_mutate(id.clone(), |maybe_details| {
				let d = maybe_details.as_mut().ok_or(Error::<T, I>::Unknown)?;
				ensure!(origin == d.admin, Error::<T, I>::NoPermission);
				ensure!(d.status == AssetStatus::Frozen, Error::<T, I>::NotFrozen);

				d.status = AssetStatus::Live;

				Self::deposit_event(Event::<T, I>::AssetThawed { asset_id: id });
				Ok(())
			})
		}

		/// Change the Owner of an asset.
		///
		/// Origin must be Signed and the sender should be the Owner of the asset `id`.
		///
		/// - `id`: The identifier of the asset.
		/// - `owner`: The new Owner of this asset.
		///
		/// Emits `OwnerChanged`.
		///
		/// Weight: `O(1)`
		#[pallet::call_index(15)]
		pub fn transfer_ownership(
			origin: OriginFor<T>,
			id: T::AssetIdParameter,
			owner: AccountIdLookupOf<T>,
		) -> DispatchResult {
			let origin = ensure_signed(origin)?;
			let owner = T::Lookup::lookup(owner)?;
			let id: T::AssetId = id.into();

			Asset::<T, I>::try_mutate(id.clone(), |maybe_details| {
				let details = maybe_details.as_mut().ok_or(Error::<T, I>::Unknown)?;
				ensure!(details.status == AssetStatus::Live, Error::<T, I>::AssetNotLive);
				ensure!(origin == details.owner, Error::<T, I>::NoPermission);
				if details.owner == owner {
					return Ok(())
				}

				let metadata_deposit = Metadata::<T, I>::get(&id).deposit;
				let deposit = details.deposit + metadata_deposit;

				// Move the deposit to the new owner.
				T::Currency::repatriate_reserved(&details.owner, &owner, deposit, Reserved)?;

				details.owner = owner.clone();

				Self::deposit_event(Event::OwnerChanged { asset_id: id, owner });
				Ok(())
			})
		}

		/// Change the Issuer, Admin and Freezer of an asset.
		///
		/// Origin must be Signed and the sender should be the Owner of the asset `id`.
		///
		/// - `id`: The identifier of the asset to be frozen.
		/// - `issuer`: The new Issuer of this asset.
		/// - `admin`: The new Admin of this asset.
		/// - `freezer`: The new Freezer of this asset.
		///
		/// Emits `TeamChanged`.
		///
		/// Weight: `O(1)`
		#[pallet::call_index(16)]
		pub fn set_team(
			origin: OriginFor<T>,
			id: T::AssetIdParameter,
			issuer: AccountIdLookupOf<T>,
			admin: AccountIdLookupOf<T>,
			freezer: AccountIdLookupOf<T>,
		) -> DispatchResult {
			let origin = ensure_signed(origin)?;
			let issuer = T::Lookup::lookup(issuer)?;
			let admin = T::Lookup::lookup(admin)?;
			let freezer = T::Lookup::lookup(freezer)?;
			let id: T::AssetId = id.into();

			Asset::<T, I>::try_mutate(id.clone(), |maybe_details| {
				let details = maybe_details.as_mut().ok_or(Error::<T, I>::Unknown)?;
				ensure!(details.status == AssetStatus::Live, Error::<T, I>::AssetNotLive);
				ensure!(origin == details.owner, Error::<T, I>::NoPermission);

				details.issuer = issuer.clone();
				details.admin = admin.clone();
				details.freezer = freezer.clone();

				Self::deposit_event(Event::TeamChanged { asset_id: id, issuer, admin, freezer });
				Ok(())
			})
		}

		/// Set the metadata for an asset.
		///
		/// Origin must be Signed and the sender should be the Owner of the asset `id`.
		///
		/// Funds of sender are reserved according to the formula:
		/// `MetadataDepositBase + MetadataDepositPerByte * (name.len + symbol.len)` taking into
		/// account any already reserved funds.
		///
		/// - `id`: The identifier of the asset to update.
		/// - `name`: The user friendly name of this asset. Limited in length by `StringLimit`.
		/// - `symbol`: The exchange symbol for this asset. Limited in length by `StringLimit`.
		/// - `decimals`: The number of decimals this asset uses to represent one unit.
		///
		/// Emits `MetadataSet`.
		///
		/// Weight: `O(1)`
		#[pallet::call_index(17)]
		#[pallet::weight(T::WeightInfo::set_metadata(name.len() as u32, symbol.len() as u32))]
		pub fn set_metadata(
			origin: OriginFor<T>,
			id: T::AssetIdParameter,
			name: Vec<u8>,
			symbol: Vec<u8>,
			decimals: u8,
		) -> DispatchResult {
			let origin = ensure_signed(origin)?;
			let id: T::AssetId = id.into();
			Self::do_set_metadata(id, &origin, name, symbol, decimals)
		}

		/// Clear the metadata for an asset.
		///
		/// Origin must be Signed and the sender should be the Owner of the asset `id`.
		///
		/// Any deposit is freed for the asset owner.
		///
		/// - `id`: The identifier of the asset to clear.
		///
		/// Emits `MetadataCleared`.
		///
		/// Weight: `O(1)`
		#[pallet::call_index(18)]
		pub fn clear_metadata(origin: OriginFor<T>, id: T::AssetIdParameter) -> DispatchResult {
			let origin = ensure_signed(origin)?;
			let id: T::AssetId = id.into();

			let d = Asset::<T, I>::get(&id).ok_or(Error::<T, I>::Unknown)?;
			ensure!(d.status == AssetStatus::Live, Error::<T, I>::AssetNotLive);
			ensure!(origin == d.owner, Error::<T, I>::NoPermission);

			Metadata::<T, I>::try_mutate_exists(id.clone(), |metadata| {
				let deposit = metadata.take().ok_or(Error::<T, I>::Unknown)?.deposit;
				T::Currency::unreserve(&d.owner, deposit);
				Self::deposit_event(Event::MetadataCleared { asset_id: id });
				Ok(())
			})
		}

		/// Force the metadata for an asset to some value.
		///
		/// Origin must be ForceOrigin.
		///
		/// Any deposit is left alone.
		///
		/// - `id`: The identifier of the asset to update.
		/// - `name`: The user friendly name of this asset. Limited in length by `StringLimit`.
		/// - `symbol`: The exchange symbol for this asset. Limited in length by `StringLimit`.
		/// - `decimals`: The number of decimals this asset uses to represent one unit.
		///
		/// Emits `MetadataSet`.
		///
		/// Weight: `O(N + S)` where N and S are the length of the name and symbol respectively.
		#[pallet::call_index(19)]
		#[pallet::weight(T::WeightInfo::force_set_metadata(name.len() as u32, symbol.len() as u32))]
		pub fn force_set_metadata(
			origin: OriginFor<T>,
			id: T::AssetIdParameter,
			name: Vec<u8>,
			symbol: Vec<u8>,
			decimals: u8,
			is_frozen: bool,
		) -> DispatchResult {
			T::ForceOrigin::ensure_origin(origin)?;
			let id: T::AssetId = id.into();

			let bounded_name: BoundedVec<u8, T::StringLimit> =
				name.clone().try_into().map_err(|_| Error::<T, I>::BadMetadata)?;

			let bounded_symbol: BoundedVec<u8, T::StringLimit> =
				symbol.clone().try_into().map_err(|_| Error::<T, I>::BadMetadata)?;

			ensure!(Asset::<T, I>::contains_key(&id), Error::<T, I>::Unknown);
			Metadata::<T, I>::try_mutate_exists(id.clone(), |metadata| {
				let deposit = metadata.take().map_or(Zero::zero(), |m| m.deposit);
				*metadata = Some(AssetMetadata {
					deposit,
					name: bounded_name,
					symbol: bounded_symbol,
					decimals,
					is_frozen,
				});

				Self::deposit_event(Event::MetadataSet {
					asset_id: id,
					name,
					symbol,
					decimals,
					is_frozen,
				});
				Ok(())
			})
		}

		/// Clear the metadata for an asset.
		///
		/// Origin must be ForceOrigin.
		///
		/// Any deposit is returned.
		///
		/// - `id`: The identifier of the asset to clear.
		///
		/// Emits `MetadataCleared`.
		///
		/// Weight: `O(1)`
		#[pallet::call_index(20)]
		pub fn force_clear_metadata(
			origin: OriginFor<T>,
			id: T::AssetIdParameter,
		) -> DispatchResult {
			T::ForceOrigin::ensure_origin(origin)?;
			let id: T::AssetId = id.into();

			let d = Asset::<T, I>::get(&id).ok_or(Error::<T, I>::Unknown)?;
			Metadata::<T, I>::try_mutate_exists(id.clone(), |metadata| {
				let deposit = metadata.take().ok_or(Error::<T, I>::Unknown)?.deposit;
				T::Currency::unreserve(&d.owner, deposit);
				Self::deposit_event(Event::MetadataCleared { asset_id: id });
				Ok(())
			})
		}

		/// Alter the attributes of a given asset.
		///
		/// Origin must be `ForceOrigin`.
		///
		/// - `id`: The identifier of the asset.
		/// - `owner`: The new Owner of this asset.
		/// - `issuer`: The new Issuer of this asset.
		/// - `admin`: The new Admin of this asset.
		/// - `freezer`: The new Freezer of this asset.
		/// - `min_balance`: The minimum balance of this new asset that any single account must
		/// have. If an account's balance is reduced below this, then it collapses to zero.
		/// - `is_sufficient`: Whether a non-zero balance of this asset is deposit of sufficient
		/// value to account for the state bloat associated with its balance storage. If set to
		/// `true`, then non-zero balances may be stored without a `consumer` reference (and thus
		/// an ED in the Balances pallet or whatever else is used to control user-account state
		/// growth).
		/// - `is_frozen`: Whether this asset class is frozen except for permissioned/admin
		/// instructions.
		///
		/// Emits `AssetStatusChanged` with the identity of the asset.
		///
		/// Weight: `O(1)`
		#[pallet::call_index(21)]
		pub fn force_asset_status(
			origin: OriginFor<T>,
			id: T::AssetIdParameter,
			owner: AccountIdLookupOf<T>,
			issuer: AccountIdLookupOf<T>,
			admin: AccountIdLookupOf<T>,
			freezer: AccountIdLookupOf<T>,
			#[pallet::compact] min_balance: T::Balance,
			is_sufficient: bool,
			is_frozen: bool,
		) -> DispatchResult {
			T::ForceOrigin::ensure_origin(origin)?;
			let id: T::AssetId = id.into();

			Asset::<T, I>::try_mutate(id.clone(), |maybe_asset| {
				let mut asset = maybe_asset.take().ok_or(Error::<T, I>::Unknown)?;
				ensure!(asset.status != AssetStatus::Destroying, Error::<T, I>::AssetNotLive);
				asset.owner = T::Lookup::lookup(owner)?;
				asset.issuer = T::Lookup::lookup(issuer)?;
				asset.admin = T::Lookup::lookup(admin)?;
				asset.freezer = T::Lookup::lookup(freezer)?;
				asset.min_balance = min_balance;
				asset.is_sufficient = is_sufficient;
				if is_frozen {
					asset.status = AssetStatus::Frozen;
				} else {
					asset.status = AssetStatus::Live;
				}
				*maybe_asset = Some(asset);

				Self::deposit_event(Event::AssetStatusChanged { asset_id: id });
				Ok(())
			})
		}

		/// Approve an amount of asset for transfer by a delegated third-party account.
		///
		/// Origin must be Signed.
		///
		/// Ensures that `ApprovalDeposit` worth of `Currency` is reserved from signing account
		/// for the purpose of holding the approval. If some non-zero amount of assets is already
		/// approved from signing account to `delegate`, then it is topped up or unreserved to
		/// meet the right value.
		///
		/// NOTE: The signing account does not need to own `amount` of assets at the point of
		/// making this call.
		///
		/// - `id`: The identifier of the asset.
		/// - `delegate`: The account to delegate permission to transfer asset.
		/// - `amount`: The amount of asset that may be transferred by `delegate`. If there is
		/// already an approval in place, then this acts additively.
		///
		/// Emits `ApprovedTransfer` on success.
		///
		/// Weight: `O(1)`
		#[pallet::call_index(22)]
		pub fn approve_transfer(
			origin: OriginFor<T>,
			id: T::AssetIdParameter,
			delegate: AccountIdLookupOf<T>,
			#[pallet::compact] amount: T::Balance,
		) -> DispatchResult {
			let owner = ensure_signed(origin)?;
			let delegate = T::Lookup::lookup(delegate)?;
			let id: T::AssetId = id.into();
			Self::do_approve_transfer(id, &owner, &delegate, amount)
		}

		/// Cancel all of some asset approved for delegated transfer by a third-party account.
		///
		/// Origin must be Signed and there must be an approval in place between signer and
		/// `delegate`.
		///
		/// Unreserves any deposit previously reserved by `approve_transfer` for the approval.
		///
		/// - `id`: The identifier of the asset.
		/// - `delegate`: The account delegated permission to transfer asset.
		///
		/// Emits `ApprovalCancelled` on success.
		///
		/// Weight: `O(1)`
		#[pallet::call_index(23)]
		pub fn cancel_approval(
			origin: OriginFor<T>,
			id: T::AssetIdParameter,
			delegate: AccountIdLookupOf<T>,
		) -> DispatchResult {
			let owner = ensure_signed(origin)?;
			let delegate = T::Lookup::lookup(delegate)?;
			let id: T::AssetId = id.into();
			let mut d = Asset::<T, I>::get(&id).ok_or(Error::<T, I>::Unknown)?;
			ensure!(d.status == AssetStatus::Live, Error::<T, I>::AssetNotLive);

			let approval = Approvals::<T, I>::take((id.clone(), &owner, &delegate))
				.ok_or(Error::<T, I>::Unknown)?;
			T::Currency::unreserve(&owner, approval.deposit);

			d.approvals.saturating_dec();
			Asset::<T, I>::insert(id.clone(), d);

			Self::deposit_event(Event::ApprovalCancelled { asset_id: id, owner, delegate });
			Ok(())
		}

		/// Cancel all of some asset approved for delegated transfer by a third-party account.
		///
		/// Origin must be either ForceOrigin or Signed origin with the signer being the Admin
		/// account of the asset `id`.
		///
		/// Unreserves any deposit previously reserved by `approve_transfer` for the approval.
		///
		/// - `id`: The identifier of the asset.
		/// - `delegate`: The account delegated permission to transfer asset.
		///
		/// Emits `ApprovalCancelled` on success.
		///
		/// Weight: `O(1)`
		#[pallet::call_index(24)]
		pub fn force_cancel_approval(
			origin: OriginFor<T>,
			id: T::AssetIdParameter,
			owner: AccountIdLookupOf<T>,
			delegate: AccountIdLookupOf<T>,
		) -> DispatchResult {
			let id: T::AssetId = id.into();
			let mut d = Asset::<T, I>::get(&id).ok_or(Error::<T, I>::Unknown)?;
			ensure!(d.status == AssetStatus::Live, Error::<T, I>::AssetNotLive);
			T::ForceOrigin::try_origin(origin)
				.map(|_| ())
				.or_else(|origin| -> DispatchResult {
					let origin = ensure_signed(origin)?;
					ensure!(origin == d.admin, Error::<T, I>::NoPermission);
					Ok(())
				})?;

			let owner = T::Lookup::lookup(owner)?;
			let delegate = T::Lookup::lookup(delegate)?;

			let approval = Approvals::<T, I>::take((id.clone(), &owner, &delegate))
				.ok_or(Error::<T, I>::Unknown)?;
			T::Currency::unreserve(&owner, approval.deposit);
			d.approvals.saturating_dec();
			Asset::<T, I>::insert(id.clone(), d);

			Self::deposit_event(Event::ApprovalCancelled { asset_id: id, owner, delegate });
			Ok(())
		}

		/// Transfer some asset balance from a previously delegated account to some third-party
		/// account.
		///
		/// Origin must be Signed and there must be an approval in place by the `owner` to the
		/// signer.
		///
		/// If the entire amount approved for transfer is transferred, then any deposit previously
		/// reserved by `approve_transfer` is unreserved.
		///
		/// - `id`: The identifier of the asset.
		/// - `owner`: The account which previously approved for a transfer of at least `amount` and
		/// from which the asset balance will be withdrawn.
		/// - `destination`: The account to which the asset balance of `amount` will be transferred.
		/// - `amount`: The amount of assets to transfer.
		///
		/// Emits `TransferredApproved` on success.
		///
		/// Weight: `O(1)`
		#[pallet::call_index(25)]
		pub fn transfer_approved(
			origin: OriginFor<T>,
			id: T::AssetIdParameter,
			owner: AccountIdLookupOf<T>,
			destination: AccountIdLookupOf<T>,
			#[pallet::compact] amount: T::Balance,
		) -> DispatchResult {
			let delegate = ensure_signed(origin)?;
			let owner = T::Lookup::lookup(owner)?;
			let destination = T::Lookup::lookup(destination)?;
			let id: T::AssetId = id.into();
			Self::do_transfer_approved(id, &owner, &delegate, &destination, amount)
		}

		/// Create an asset account for non-provider assets.
		///
		/// A deposit will be taken from the signer account.
		///
		/// - `origin`: Must be Signed; the signer account must have sufficient funds for a deposit
		///   to be taken.
		/// - `id`: The identifier of the asset for the account to be created.
		///
		/// Emits `Touched` event when successful.
		#[pallet::call_index(26)]
		#[pallet::weight(T::WeightInfo::touch())]
		pub fn touch(origin: OriginFor<T>, id: T::AssetIdParameter) -> DispatchResult {
			let who = ensure_signed(origin)?;
			let id: T::AssetId = id.into();
			Self::do_touch(id, who.clone(), who, false)
		}

		/// Return the deposit (if any) of an asset account or a consumer reference (if any) of an
		/// account.
		///
		/// The origin must be Signed.
		///
		/// - `id`: The identifier of the asset for which the caller would like the deposit
		///   refunded.
		/// - `allow_burn`: If `true` then assets may be destroyed in order to complete the refund.
		///
		/// Emits `Refunded` event when successful.
		#[pallet::call_index(27)]
		#[pallet::weight(T::WeightInfo::refund())]
		pub fn refund(
			origin: OriginFor<T>,
			id: T::AssetIdParameter,
			allow_burn: bool,
		) -> DispatchResult {
			let id: T::AssetId = id.into();
			Self::do_refund(id, ensure_signed(origin)?, allow_burn)
		}

		/// Sets the minimum balance of an asset.
		///
		/// Only works if there aren't any accounts that are holding the asset or if
		/// the new value of `min_balance` is less than the old one.
		///
		/// Origin must be Signed and the sender has to be the Owner of the
		/// asset `id`.
		///
		/// - `id`: The identifier of the asset.
		/// - `min_balance`: The new value of `min_balance`.
		///
		/// Emits `AssetMinBalanceChanged` event when successful.
		#[pallet::call_index(28)]
		pub fn set_min_balance(
			origin: OriginFor<T>,
			id: T::AssetIdParameter,
			min_balance: T::Balance,
		) -> DispatchResult {
			let origin = ensure_signed(origin)?;
			let id: T::AssetId = id.into();

			let mut details = Asset::<T, I>::get(&id).ok_or(Error::<T, I>::Unknown)?;
			ensure!(origin == details.owner, Error::<T, I>::NoPermission);

			let old_min_balance = details.min_balance;
			// If the asset is marked as sufficient it won't be allowed to
			// change the min_balance.
			ensure!(!details.is_sufficient, Error::<T, I>::NoPermission);

			// Ensure that either the new min_balance is less than old
			// min_balance or there aren't any accounts holding the asset.
			ensure!(
				min_balance < old_min_balance || details.accounts == 0,
				Error::<T, I>::NoPermission
			);

			details.min_balance = min_balance;
			Asset::<T, I>::insert(&id, details);

			Self::deposit_event(Event::AssetMinBalanceChanged {
				asset_id: id,
				new_min_balance: min_balance,
			});
			Ok(())
		}

		/// Create an asset account for `who`.
		///
		/// A deposit will be taken from the signer account.
		///
		/// - `origin`: Must be Signed by `Freezer` or `Admin` of the asset `id`; the signer account
		///   must have sufficient funds for a deposit to be taken.
		/// - `id`: The identifier of the asset for the account to be created.
		/// - `who`: The account to be created.
		///
		/// Emits `Touched` event when successful.
		#[pallet::call_index(29)]
		#[pallet::weight(T::WeightInfo::touch_other())]
		pub fn touch_other(
			origin: OriginFor<T>,
			id: T::AssetIdParameter,
			who: AccountIdLookupOf<T>,
		) -> DispatchResult {
			let origin = ensure_signed(origin)?;
			let who = T::Lookup::lookup(who)?;
			let id: T::AssetId = id.into();
			Self::do_touch(id, who, origin, true)
		}

		/// Return the deposit (if any) of a target asset account. Useful if you are the depositor.
		///
		/// The origin must be Signed and either the account owner, depositor, or asset `Admin`. In
		/// order to burn a non-zero balance of the asset, the caller must be the account and should
		/// use `refund`.
		///
		/// - `id`: The identifier of the asset for the account holding a deposit.
		/// - `who`: The account to refund.
		///
		/// Emits `Refunded` event when successful.
		#[pallet::call_index(30)]
		#[pallet::weight(T::WeightInfo::refund_other())]
		pub fn refund_other(
			origin: OriginFor<T>,
			id: T::AssetIdParameter,
			who: AccountIdLookupOf<T>,
		) -> DispatchResult {
			let origin = ensure_signed(origin)?;
			let who = T::Lookup::lookup(who)?;
			let id: T::AssetId = id.into();
			Self::do_refund_other(id, &who, Some(origin))
		}

		/// Disallow further unprivileged transfers of an asset `id` to and from an account `who`.
		///
		/// Origin must be Signed and the sender should be the Freezer of the asset `id`.
		///
		/// - `id`: The identifier of the account's asset.
		/// - `who`: The account to be unblocked.
		///
		/// Emits `Blocked`.
		///
		/// Weight: `O(1)`
		#[pallet::call_index(31)]
		pub fn block(
			origin: OriginFor<T>,
			id: T::AssetIdParameter,
			who: AccountIdLookupOf<T>,
		) -> DispatchResult {
			let origin = ensure_signed(origin)?;
			let id: T::AssetId = id.into();

			let d = Asset::<T, I>::get(&id).ok_or(Error::<T, I>::Unknown)?;
			ensure!(
				d.status == AssetStatus::Live || d.status == AssetStatus::Frozen,
				Error::<T, I>::IncorrectStatus
			);
			ensure!(origin == d.freezer, Error::<T, I>::NoPermission);
			let who = T::Lookup::lookup(who)?;

			Account::<T, I>::try_mutate(&id, &who, |maybe_account| -> DispatchResult {
				maybe_account.as_mut().ok_or(Error::<T, I>::NoAccount)?.status =
					AccountStatus::Blocked;
				Ok(())
			})?;

			Self::deposit_event(Event::<T, I>::Blocked { asset_id: id, who });
			Ok(())
		}

		/// Transfer the entire transferable balance from the caller asset account.
		///
		/// NOTE: This function only attempts to transfer _transferable_ balances. This means that
		/// any held, frozen, or minimum balance (when `keep_alive` is `true`), will not be
		/// transferred by this function. To ensure that this function results in a killed account,
		/// you might need to prepare the account by removing any reference counters, storage
		/// deposits, etc...
		///
		/// The dispatch origin of this call must be Signed.
		///
		/// - `id`: The identifier of the asset for the account holding a deposit.
		/// - `dest`: The recipient of the transfer.
		/// - `keep_alive`: A boolean to determine if the `transfer_all` operation should send all
		///   of the funds the asset account has, causing the sender asset account to be killed
		///   (false), or transfer everything except at least the minimum balance, which will
		///   guarantee to keep the sender asset account alive (true).
		#[pallet::call_index(32)]
		#[pallet::weight(T::WeightInfo::transfer_all())]
		pub fn transfer_all(
			origin: OriginFor<T>,
			id: T::AssetIdParameter,
			dest: AccountIdLookupOf<T>,
			keep_alive: bool,
		) -> DispatchResult {
			let transactor = ensure_signed(origin)?;
			let keep_alive = if keep_alive { Preserve } else { Expendable };
			let reducible_balance = <Self as fungibles::Inspect<_>>::reducible_balance(
				id.clone().into(),
				&transactor,
				keep_alive,
				Fortitude::Polite,
			);
			let dest = T::Lookup::lookup(dest)?;
			<Self as fungibles::Mutate<_>>::transfer(
				id.into(),
				&transactor,
				&dest,
				reducible_balance,
				keep_alive,
			)?;
			Ok(())
		}
	}

	/// Implements [`AccountTouch`] trait.
	/// Note that a depositor can be any account, without any specific privilege.
	/// This implementation is supposed to be used only for creation of system accounts.
	impl<T: Config<I>, I: 'static> AccountTouch<T::AssetId, T::AccountId> for Pallet<T, I> {
		type Balance = DepositBalanceOf<T, I>;

		fn deposit_required(_: T::AssetId) -> Self::Balance {
			T::AssetAccountDeposit::get()
		}

		fn should_touch(asset: T::AssetId, who: &T::AccountId) -> bool {
			match Asset::<T, I>::get(&asset) {
				// refer to the [`Self::new_account`] function for more details.
				Some(info) if info.is_sufficient => false,
				Some(_) if frame_system::Pallet::<T>::can_accrue_consumers(who, 2) => false,
				Some(_) => !Account::<T, I>::contains_key(asset, who),
				_ => true,
			}
		}

		fn touch(
			asset: T::AssetId,
			who: &T::AccountId,
			depositor: &T::AccountId,
		) -> DispatchResult {
			Self::do_touch(asset, who.clone(), depositor.clone(), false)
		}
	}

	/// Implements [`ContainsPair`] trait for a pair of asset and account IDs.
	impl<T: Config<I>, I: 'static> ContainsPair<T::AssetId, T::AccountId> for Pallet<T, I> {
		/// Check if an account with the given asset ID and account address exists.
		fn contains(asset: &T::AssetId, who: &T::AccountId) -> bool {
			Account::<T, I>::contains_key(asset, who)
		}
	}
}

sp_core::generate_feature_enabled_macro!(runtime_benchmarks_enabled, feature = "runtime-benchmarks", $);