git.delta.rocks / unique-network / refs/commits / 7d1859c1e151

1// Copyright 2019-2022 Unique Network (Gibraltar) Ltd.2// This file is part of Unique Network.34// Unique Network is free software: you can redistribute it and/or modify5// it under the terms of the GNU General Public License as published by6// the Free Software Foundation, either version 3 of the License, or7// (at your option) any later version.89// Unique Network is distributed in the hope that it will be useful,10// but WITHOUT ANY WARRANTY; without even the implied warranty of11// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the12// GNU General Public License for more details.1314// You should have received a copy of the GNU General Public License15// along with Unique Network. If not, see <http://www.gnu.org/licenses/>.1617//! # Refungible Pallet18//!19//! The Refungible pallet provides functionality for handling refungible collections and tokens.20//!21//! - [`Config`]22//! - [`RefungibleHandle`]23//! - [`Pallet`]24//! - [`CommonWeights`](common::CommonWeights)25//!26//! ## Overview27//!28//! The Refungible pallet provides functions for:29//!30//! - RFT collection creation and removal31//! - Minting and burning of RFT tokens32//! - Partition and repartition of RFT tokens33//! - Retrieving number of pieces of RFT token34//! - Retrieving account balances35//! - Transfering RFT token pieces36//! - Burning RFT token pieces37//! - Setting and checking allowance for RFT tokens38//!39//! ### Terminology40//!41//! - **RFT token:** Non fungible token that was partitioned to pieces. If an account owns all42//!   of the RFT token pieces than it owns the RFT token and can repartition it.43//!44//! - **RFT Collection:** A collection of RFT tokens. All RFT tokens are part of a collection.45//!   Each collection has its own settings and set of permissions.46//!47//! - **RFT token piece:** A fungible part of an RFT token.48//!49//! - **Balance:** RFT token pieces owned by an account50//!51//! - **Allowance:** Maximum number of RFT token pieces that one account is allowed to52//!   transfer from the balance of another account53//!54//! - **Burning:** The process of “deleting” a token from a collection or removing token pieces from55//!   an account balance.56//!57//! ### Implementations58//!59//! The Refungible pallet provides implementations for the following traits. If these traits provide60//! the functionality that you need, then you can avoid coupling with the Refungible pallet.61//!62//! - [`CommonWeightInfo`](pallet_common::CommonWeightInfo): Functions for retrieval of transaction weight63//! - [`CommonCollectionOperations`](pallet_common::CommonCollectionOperations): Functions for dealing64//!   with collections65//! - [`RefungibleExtensions`](pallet_common::RefungibleExtensions): Functions specific for refungible66//!   collection67//!68//! ## Interface69//!70//! ### Dispatchable Functions71//!72//! - `init_collection` - Create RFT collection. RFT collection can be configured to allow or deny access for73//!   some accounts.74//! - `destroy_collection` - Destroy exising RFT collection. There should be no tokens in the collection.75//! - `burn` - Burn some amount of RFT token pieces owned by account. Burns the RFT token if no pieces left.76//! - `transfer` - Transfer some amount of RFT token pieces. Transfers should be enabled for RFT collection.77//!   Nests the RFT token if RFT token pieces are sent to another token.78//! - `create_item` - Mint RFT token in collection. Sender should have permission to mint tokens.79//! - `set_allowance` - Set allowance for another account to transfer balance from sender's account.80//! - `repartition` - Repartition token to selected number of pieces. Sender should own all existing pieces.81//!82//! ## Assumptions83//!84//! * Total number of pieces for one token shouldn't exceed `up_data_structs::MAX_REFUNGIBLE_PIECES`.85//! * Total number of tokens of all types shouldn't be greater than `up_data_structs::MAX_TOKEN_PREFIX_LENGTH`.86//! * Sender should be in collection's allow list to perform operations on tokens.8788#![cfg_attr(not(feature = "std"), no_std)]8990use crate::erc_token::ERC20Events;91use crate::erc::ERC721Events;9293use codec::{Encode, Decode, MaxEncodedLen};94use core::ops::Deref;95use evm_coder::ToLog;96use frame_support::{BoundedVec, ensure, fail, storage::with_transaction, transactional};97use pallet_evm::{account::CrossAccountId, Pallet as PalletEvm};98use pallet_evm_coder_substrate::WithRecorder;99use pallet_common::{100	CommonCollectionOperations, Error as CommonError, Event as CommonEvent,101	eth::collection_id_to_address, Pallet as PalletCommon,102};103use pallet_structure::Pallet as PalletStructure;104use scale_info::TypeInfo;105use sp_core::H160;106use sp_runtime::{ArithmeticError, DispatchError, DispatchResult, TransactionOutcome};107use sp_std::{vec::Vec, vec, collections::btree_map::BTreeMap};108use up_data_structs::{109	AccessMode, budget::Budget, CollectionId, CreateCollectionData, CreateRefungibleExData,110	CustomDataLimit, mapping::TokenAddressMapping, MAX_REFUNGIBLE_PIECES, TokenId, Property,111	PropertyKey, PropertyKeyPermission, PropertyPermission, PropertyScope, PropertyValue,112	TrySetProperty,113};114115pub use pallet::*;116#[cfg(feature = "runtime-benchmarks")]117pub mod benchmarking;118pub mod common;119pub mod erc;120pub mod erc_token;121pub mod weights;122123pub type CreateItemData<T> =124	CreateRefungibleExData<<T as pallet_evm::account::Config>::CrossAccountId>;125pub(crate) type SelfWeightOf<T> = <T as Config>::WeightInfo;126127/// Token data, stored independently from other data used to describe it128/// for the convenience of database access. Notably contains the token metadata.129#[struct_versioning::versioned(version = 2, upper)]130#[derive(Encode, Decode, Default, TypeInfo, MaxEncodedLen)]131pub struct ItemData {132	pub const_data: BoundedVec<u8, CustomDataLimit>,133134	#[version(..2)]135	pub variable_data: BoundedVec<u8, CustomDataLimit>,136}137138#[frame_support::pallet]139pub mod pallet {140	use super::*;141	use frame_support::{142		Blake2_128, Blake2_128Concat, Twox64Concat, pallet_prelude::*, storage::Key,143		traits::StorageVersion,144	};145	use frame_system::pallet_prelude::*;146	use up_data_structs::{CollectionId, TokenId};147	use super::weights::WeightInfo;148149	#[pallet::error]150	pub enum Error<T> {151		/// Not Refungible item data used to mint in Refungible collection.152		NotRefungibleDataUsedToMintFungibleCollectionToken,153		/// Maximum refungibility exceeded.154		WrongRefungiblePieces,155		/// Refungible token can't be repartitioned by user who isn't owns all pieces.156		RepartitionWhileNotOwningAllPieces,157		/// Refungible token can't nest other tokens.158		RefungibleDisallowsNesting,159		/// Setting item properties is not allowed.160		SettingPropertiesNotAllowed,161	}162163	#[pallet::config]164	pub trait Config:165		frame_system::Config + pallet_common::Config + pallet_structure::Config166	{167		type WeightInfo: WeightInfo;168	}169170	const STORAGE_VERSION: StorageVersion = StorageVersion::new(1);171172	#[pallet::pallet]173	#[pallet::storage_version(STORAGE_VERSION)]174	#[pallet::generate_store(pub(super) trait Store)]175	pub struct Pallet<T>(_);176177	/// Total amount of minted tokens in a collection.178	#[pallet::storage]179	pub type TokensMinted<T: Config> =180		StorageMap<Hasher = Twox64Concat, Key = CollectionId, Value = u32, QueryKind = ValueQuery>;181182	/// Amount of tokens burnt in a collection.183	#[pallet::storage]184	pub type TokensBurnt<T: Config> =185		StorageMap<Hasher = Twox64Concat, Key = CollectionId, Value = u32, QueryKind = ValueQuery>;186187	/// Token data, used to partially describe a token.188	#[pallet::storage]189	pub type TokenData<T: Config> = StorageNMap<190		Key = (Key<Twox64Concat, CollectionId>, Key<Twox64Concat, TokenId>),191		Value = ItemData,192		QueryKind = ValueQuery,193	>;194195	/// Amount of pieces a refungible token is split into.196	#[pallet::storage]197	#[pallet::getter(fn token_properties)]198	pub type TokenProperties<T: Config> = StorageNMap<199		Key = (Key<Twox64Concat, CollectionId>, Key<Twox64Concat, TokenId>),200		Value = up_data_structs::Properties,201		QueryKind = ValueQuery,202		OnEmpty = up_data_structs::TokenProperties,203	>;204205	/// Total amount of pieces for token206	#[pallet::storage]207	pub type TotalSupply<T: Config> = StorageNMap<208		Key = (Key<Twox64Concat, CollectionId>, Key<Twox64Concat, TokenId>),209		Value = u128,210		QueryKind = ValueQuery,211	>;212213	/// Used to enumerate tokens owned by account.214	#[pallet::storage]215	pub type Owned<T: Config> = StorageNMap<216		Key = (217			Key<Twox64Concat, CollectionId>,218			Key<Blake2_128Concat, T::CrossAccountId>,219			Key<Twox64Concat, TokenId>,220		),221		Value = bool,222		QueryKind = ValueQuery,223	>;224225	/// Amount of tokens (not pieces) partially owned by an account within a collection.226	#[pallet::storage]227	pub type AccountBalance<T: Config> = StorageNMap<228		Key = (229			Key<Twox64Concat, CollectionId>,230			// Owner231			Key<Blake2_128Concat, T::CrossAccountId>,232		),233		Value = u32,234		QueryKind = ValueQuery,235	>;236237	/// Amount of token pieces owned by account.238	#[pallet::storage]239	pub type Balance<T: Config> = StorageNMap<240		Key = (241			Key<Twox64Concat, CollectionId>,242			Key<Twox64Concat, TokenId>,243			// Owner244			Key<Blake2_128Concat, T::CrossAccountId>,245		),246		Value = u128,247		QueryKind = ValueQuery,248	>;249250	/// Allowance set by a token owner for another user to perform one of certain transactions on a number of pieces of a token.251	#[pallet::storage]252	pub type Allowance<T: Config> = StorageNMap<253		Key = (254			Key<Twox64Concat, CollectionId>,255			Key<Twox64Concat, TokenId>,256			// Owner257			Key<Blake2_128, T::CrossAccountId>,258			// Spender259			Key<Blake2_128Concat, T::CrossAccountId>,260		),261		Value = u128,262		QueryKind = ValueQuery,263	>;264265	#[pallet::hooks]266	impl<T: Config> Hooks<BlockNumberFor<T>> for Pallet<T> {267		fn on_runtime_upgrade() -> Weight {268			if StorageVersion::get::<Pallet<T>>() < StorageVersion::new(1) {269				<TokenData<T>>::translate_values::<ItemDataVersion1, _>(|v| {270					Some(<ItemDataVersion2>::from(v))271				})272			}273274			0275		}276	}277}278279pub struct RefungibleHandle<T: Config>(pallet_common::CollectionHandle<T>);280impl<T: Config> RefungibleHandle<T> {281	pub fn cast(inner: pallet_common::CollectionHandle<T>) -> Self {282		Self(inner)283	}284	pub fn into_inner(self) -> pallet_common::CollectionHandle<T> {285		self.0286	}287	pub fn common_mut(&mut self) -> &mut pallet_common::CollectionHandle<T> {288		&mut self.0289	}290}291292impl<T: Config> Deref for RefungibleHandle<T> {293	type Target = pallet_common::CollectionHandle<T>;294295	fn deref(&self) -> &Self::Target {296		&self.0297	}298}299300impl<T: Config> WithRecorder<T> for RefungibleHandle<T> {301	fn recorder(&self) -> &pallet_evm_coder_substrate::SubstrateRecorder<T> {302		self.0.recorder()303	}304	fn into_recorder(self) -> pallet_evm_coder_substrate::SubstrateRecorder<T> {305		self.0.into_recorder()306	}307}308309impl<T: Config> Pallet<T> {310	/// Get number of RFT tokens in collection311	pub fn total_supply(collection: &RefungibleHandle<T>) -> u32 {312		<TokensMinted<T>>::get(collection.id) - <TokensBurnt<T>>::get(collection.id)313	}314315	/// Check that RFT token exists316	///317	/// - `token`: Token ID.318	pub fn token_exists(collection: &RefungibleHandle<T>, token: TokenId) -> bool {319		<TotalSupply<T>>::contains_key((collection.id, token))320	}321322	pub fn set_scoped_token_property(323		collection_id: CollectionId,324		token_id: TokenId,325		scope: PropertyScope,326		property: Property,327	) -> DispatchResult {328		TokenProperties::<T>::try_mutate((collection_id, token_id), |properties| {329			properties.try_scoped_set(scope, property.key, property.value)330		})331		.map_err(<CommonError<T>>::from)?;332333		Ok(())334	}335336	pub fn set_scoped_token_properties(337		collection_id: CollectionId,338		token_id: TokenId,339		scope: PropertyScope,340		properties: impl Iterator<Item = Property>,341	) -> DispatchResult {342		TokenProperties::<T>::try_mutate((collection_id, token_id), |stored_properties| {343			stored_properties.try_scoped_set_from_iter(scope, properties)344		})345		.map_err(<CommonError<T>>::from)?;346347		Ok(())348	}349}350351// unchecked calls skips any permission checks352impl<T: Config> Pallet<T> {353	/// Create RFT collection354	///355	/// `init_collection` will take non-refundable deposit for collection creation.356	///357	/// - `data`: Contains settings for collection limits and permissions.358	pub fn init_collection(359		owner: T::CrossAccountId,360		data: CreateCollectionData<T::AccountId>,361	) -> Result<CollectionId, DispatchError> {362		<PalletCommon<T>>::init_collection(owner, data, false)363	}364365	/// Destroy RFT collection366	///367	/// `destroy_collection` will throw error if collection contains any tokens.368	/// Only owner can destroy collection.369	pub fn destroy_collection(370		collection: RefungibleHandle<T>,371		sender: &T::CrossAccountId,372	) -> DispatchResult {373		let id = collection.id;374375		if Self::collection_has_tokens(id) {376			return Err(<CommonError<T>>::CantDestroyNotEmptyCollection.into());377		}378379		// =========380381		PalletCommon::destroy_collection(collection.0, sender)?;382383		<TokensMinted<T>>::remove(id);384		<TokensBurnt<T>>::remove(id);385		<TokenData<T>>::remove_prefix((id,), None);386		<TotalSupply<T>>::remove_prefix((id,), None);387		<Balance<T>>::remove_prefix((id,), None);388		<Allowance<T>>::remove_prefix((id,), None);389		<Owned<T>>::remove_prefix((id,), None);390		<AccountBalance<T>>::remove_prefix((id,), None);391		Ok(())392	}393394	fn collection_has_tokens(collection_id: CollectionId) -> bool {395		<TokenData<T>>::iter_prefix((collection_id,))396			.next()397			.is_some()398	}399400	pub fn burn_token_unchecked(401		collection: &RefungibleHandle<T>,402		token_id: TokenId,403	) -> DispatchResult {404		let burnt = <TokensBurnt<T>>::get(collection.id)405			.checked_add(1)406			.ok_or(ArithmeticError::Overflow)?;407408		<TokensBurnt<T>>::insert(collection.id, burnt);409		<TokenData<T>>::remove((collection.id, token_id));410		<TokenProperties<T>>::remove((collection.id, token_id));411		<TotalSupply<T>>::remove((collection.id, token_id));412		<Balance<T>>::remove_prefix((collection.id, token_id), None);413		<Allowance<T>>::remove_prefix((collection.id, token_id), None);414		// TODO: ERC721 transfer event415		Ok(())416	}417418	/// Burn RFT token pieces419	///420	/// `burn` will decrease total amount of token pieces and amount owned by sender.421	/// `burn` can be called even if there are multiple owners of the RFT token.422	/// If sender wouldn't have any pieces left after `burn` than she will stop being423	/// one of the owners of the token. If there is no account that owns any pieces of424	/// the token than token will be burned too.425	///426	/// - `amount`: Amount of token pieces to burn.427	/// - `token`: Token who's pieces should be burned428	/// - `collection`: Collection that contains the token429	pub fn burn(430		collection: &RefungibleHandle<T>,431		owner: &T::CrossAccountId,432		token: TokenId,433		amount: u128,434	) -> DispatchResult {435		let total_supply = <TotalSupply<T>>::get((collection.id, token))436			.checked_sub(amount)437			.ok_or(<CommonError<T>>::TokenValueTooLow)?;438439		// This was probally last owner of this token?440		if total_supply == 0 {441			// Ensure user actually owns this amount442			ensure!(443				<Balance<T>>::get((collection.id, token, owner)) == amount,444				<CommonError<T>>::TokenValueTooLow445			);446			let account_balance = <AccountBalance<T>>::get((collection.id, owner))447				.checked_sub(1)448				// Should not occur449				.ok_or(ArithmeticError::Underflow)?;450451			// =========452453			<Owned<T>>::remove((collection.id, owner, token));454			<PalletStructure<T>>::unnest_if_nested(owner, collection.id, token);455			<AccountBalance<T>>::insert((collection.id, owner), account_balance);456			Self::burn_token_unchecked(collection, token)?;457			<PalletCommon<T>>::deposit_event(CommonEvent::ItemDestroyed(458				collection.id,459				token,460				owner.clone(),461				amount,462			));463			return Ok(());464		}465466		let balance = <Balance<T>>::get((collection.id, token, owner))467			.checked_sub(amount)468			.ok_or(<CommonError<T>>::TokenValueTooLow)?;469		let account_balance = if balance == 0 {470			<AccountBalance<T>>::get((collection.id, owner))471				.checked_sub(1)472				// Should not occur473				.ok_or(ArithmeticError::Underflow)?474		} else {475			0476		};477478		// =========479480		if balance == 0 {481			<Owned<T>>::remove((collection.id, owner, token));482			<PalletStructure<T>>::unnest_if_nested(owner, collection.id, token);483			<Balance<T>>::remove((collection.id, token, owner));484			<AccountBalance<T>>::insert((collection.id, owner), account_balance);485		} else {486			<Balance<T>>::insert((collection.id, token, owner), balance);487		}488		<TotalSupply<T>>::insert((collection.id, token), total_supply);489490		<PalletEvm<T>>::deposit_log(491			ERC20Events::Transfer {492				from: *owner.as_eth(),493				to: H160::default(),494				value: amount.into(),495			}496			.to_log(T::EvmTokenAddressMapping::token_to_address(497				collection.id,498				token,499			)),500		);501		<PalletCommon<T>>::deposit_event(CommonEvent::ItemDestroyed(502			collection.id,503			token,504			owner.clone(),505			amount,506		));507		Ok(())508	}509510	#[transactional]511	fn modify_token_properties(512		collection: &RefungibleHandle<T>,513		sender: &T::CrossAccountId,514		token_id: TokenId,515		properties: impl Iterator<Item = (PropertyKey, Option<PropertyValue>)>,516		is_token_create: bool,517		nesting_budget: &dyn Budget,518	) -> DispatchResult {519		let is_collection_admin = || collection.is_owner_or_admin(sender);520		let is_token_owner = || -> Result<bool, DispatchError> {521			let balance = collection.balance(sender.clone(), token_id);522			let total_pieces: u128 =523				Self::total_pieces(collection.id, token_id).unwrap_or(u128::MAX);524			if balance != total_pieces {525				return Ok(false);526			}527528			let is_bundle_owner = <PalletStructure<T>>::check_indirectly_owned(529				sender.clone(),530				collection.id,531				token_id,532				None,533				nesting_budget,534			)?;535536			Ok(is_bundle_owner)537		};538539		for (key, value) in properties {540			let permission = <PalletCommon<T>>::property_permissions(collection.id)541				.get(&key)542				.cloned()543				.unwrap_or_else(PropertyPermission::none);544545			let is_property_exists = TokenProperties::<T>::get((collection.id, token_id))546				.get(&key)547				.is_some();548549			match permission {550				PropertyPermission { mutable: false, .. } if is_property_exists => {551					return Err(<CommonError<T>>::NoPermission.into());552				}553554				PropertyPermission {555					collection_admin,556					token_owner,557					..558				} => {559					//TODO: investigate threats during public minting.560					let is_token_create =561						is_token_create && (collection_admin || token_owner) && value.is_some();562					if !(is_token_create563						|| (collection_admin && is_collection_admin())564						|| (token_owner && is_token_owner()?))565					{566						fail!(<CommonError<T>>::NoPermission);567					}568				}569			}570571			match value {572				Some(value) => {573					<TokenProperties<T>>::try_mutate((collection.id, token_id), |properties| {574						properties.try_set(key.clone(), value)575					})576					.map_err(<CommonError<T>>::from)?;577578					<PalletCommon<T>>::deposit_event(CommonEvent::TokenPropertySet(579						collection.id,580						token_id,581						key,582					));583				}584				None => {585					<TokenProperties<T>>::try_mutate((collection.id, token_id), |properties| {586						properties.remove(&key)587					})588					.map_err(<CommonError<T>>::from)?;589590					<PalletCommon<T>>::deposit_event(CommonEvent::TokenPropertyDeleted(591						collection.id,592						token_id,593						key,594					));595				}596			}597		}598599		Ok(())600	}601602	pub fn set_token_properties(603		collection: &RefungibleHandle<T>,604		sender: &T::CrossAccountId,605		token_id: TokenId,606		properties: impl Iterator<Item = Property>,607		is_token_create: bool,608		nesting_budget: &dyn Budget,609	) -> DispatchResult {610		Self::modify_token_properties(611			collection,612			sender,613			token_id,614			properties.map(|p| (p.key, Some(p.value))),615			is_token_create,616			nesting_budget,617		)618	}619620	pub fn set_token_property(621		collection: &RefungibleHandle<T>,622		sender: &T::CrossAccountId,623		token_id: TokenId,624		property: Property,625		nesting_budget: &dyn Budget,626	) -> DispatchResult {627		let is_token_create = false;628629		Self::set_token_properties(630			collection,631			sender,632			token_id,633			[property].into_iter(),634			is_token_create,635			nesting_budget,636		)637	}638639	pub fn delete_token_properties(640		collection: &RefungibleHandle<T>,641		sender: &T::CrossAccountId,642		token_id: TokenId,643		property_keys: impl Iterator<Item = PropertyKey>,644		nesting_budget: &dyn Budget,645	) -> DispatchResult {646		let is_token_create = false;647648		Self::modify_token_properties(649			collection,650			sender,651			token_id,652			property_keys.into_iter().map(|key| (key, None)),653			is_token_create,654			nesting_budget,655		)656	}657658	pub fn delete_token_property(659		collection: &RefungibleHandle<T>,660		sender: &T::CrossAccountId,661		token_id: TokenId,662		property_key: PropertyKey,663		nesting_budget: &dyn Budget,664	) -> DispatchResult {665		Self::delete_token_properties(666			collection,667			sender,668			token_id,669			[property_key].into_iter(),670			nesting_budget,671		)672	}673674	/// Transfer RFT token pieces from one account to another.675	///676	/// If the sender is no longer owns any pieces after the `transfer` than she stops being an owner of the token.677	///678	/// - `from`: Owner of token pieces to transfer.679	/// - `to`: Recepient of transfered token pieces.680	/// - `amount`: Amount of token pieces to transfer.681	/// - `token`: Token whos pieces should be transfered682	/// - `collection`: Collection that contains the token683	pub fn transfer(684		collection: &RefungibleHandle<T>,685		from: &T::CrossAccountId,686		to: &T::CrossAccountId,687		token: TokenId,688		amount: u128,689		nesting_budget: &dyn Budget,690	) -> DispatchResult {691		ensure!(692			collection.limits.transfers_enabled(),693			<CommonError<T>>::TransferNotAllowed694		);695696		if collection.permissions.access() == AccessMode::AllowList {697			collection.check_allowlist(from)?;698			collection.check_allowlist(to)?;699		}700		<PalletCommon<T>>::ensure_correct_receiver(to)?;701702		let balance_from = <Balance<T>>::get((collection.id, token, from))703			.checked_sub(amount)704			.ok_or(<CommonError<T>>::TokenValueTooLow)?;705		let mut create_target = false;706		let from_to_differ = from != to;707		let balance_to = if from != to {708			let old_balance = <Balance<T>>::get((collection.id, token, to));709			if old_balance == 0 {710				create_target = true;711			}712			Some(713				old_balance714					.checked_add(amount)715					.ok_or(ArithmeticError::Overflow)?,716			)717		} else {718			None719		};720721		let account_balance_from = if balance_from == 0 {722			Some(723				<AccountBalance<T>>::get((collection.id, from))724					.checked_sub(1)725					// Should not occur726					.ok_or(ArithmeticError::Underflow)?,727			)728		} else {729			None730		};731		// Account data is created in token, AccountBalance should be increased732		// But only if from != to as we shouldn't check overflow in this case733		let account_balance_to = if create_target && from_to_differ {734			let account_balance_to = <AccountBalance<T>>::get((collection.id, to))735				.checked_add(1)736				.ok_or(ArithmeticError::Overflow)?;737			ensure!(738				account_balance_to < collection.limits.account_token_ownership_limit(),739				<CommonError<T>>::AccountTokenLimitExceeded,740			);741742			Some(account_balance_to)743		} else {744			None745		};746747		// =========748749		<PalletStructure<T>>::nest_if_sent_to_token(750			from.clone(),751			to,752			collection.id,753			token,754			nesting_budget,755		)?;756757		if let Some(balance_to) = balance_to {758			// from != to759			if balance_from == 0 {760				<Balance<T>>::remove((collection.id, token, from));761				<PalletStructure<T>>::unnest_if_nested(from, collection.id, token);762			} else {763				<Balance<T>>::insert((collection.id, token, from), balance_from);764			}765			<Balance<T>>::insert((collection.id, token, to), balance_to);766			if let Some(account_balance_from) = account_balance_from {767				<AccountBalance<T>>::insert((collection.id, from), account_balance_from);768				<Owned<T>>::remove((collection.id, from, token));769			}770			if let Some(account_balance_to) = account_balance_to {771				<AccountBalance<T>>::insert((collection.id, to), account_balance_to);772				<Owned<T>>::insert((collection.id, to, token), true);773			}774		}775776		<PalletEvm<T>>::deposit_log(777			ERC20Events::Transfer {778				from: *from.as_eth(),779				to: *to.as_eth(),780				value: amount.into(),781			}782			.to_log(T::EvmTokenAddressMapping::token_to_address(783				collection.id,784				token,785			)),786		);787788		<PalletCommon<T>>::deposit_event(CommonEvent::Transfer(789			collection.id,790			token,791			from.clone(),792			to.clone(),793			amount,794		));795		Ok(())796	}797798	/// Batched operation to create multiple RFT tokens.799	///800	/// Same as `create_item` but creates multiple tokens.801	///802	/// - `data`: Same as 'data` in `create_item` but contains data for multiple tokens.803	pub fn create_multiple_items(804		collection: &RefungibleHandle<T>,805		sender: &T::CrossAccountId,806		data: Vec<CreateItemData<T>>,807		nesting_budget: &dyn Budget,808	) -> DispatchResult {809		if !collection.is_owner_or_admin(sender) {810			ensure!(811				collection.permissions.mint_mode(),812				<CommonError<T>>::PublicMintingNotAllowed813			);814			collection.check_allowlist(sender)?;815816			for item in data.iter() {817				for user in item.users.keys() {818					collection.check_allowlist(user)?;819				}820			}821		}822823		for item in data.iter() {824			for (owner, _) in item.users.iter() {825				<PalletCommon<T>>::ensure_correct_receiver(owner)?;826			}827		}828829		// Total pieces per tokens830		let totals = data831			.iter()832			.map(|data| {833				Ok(data834					.users835					.iter()836					.map(|u| u.1)837					.try_fold(0u128, |acc, v| acc.checked_add(*v))838					.ok_or(ArithmeticError::Overflow)?)839			})840			.collect::<Result<Vec<_>, DispatchError>>()?;841		for total in &totals {842			ensure!(843				*total <= MAX_REFUNGIBLE_PIECES,844				<Error<T>>::WrongRefungiblePieces845			);846		}847848		let first_token_id = <TokensMinted<T>>::get(collection.id);849		let tokens_minted = first_token_id850			.checked_add(data.len() as u32)851			.ok_or(ArithmeticError::Overflow)?;852		ensure!(853			tokens_minted < collection.limits.token_limit(),854			<CommonError<T>>::CollectionTokenLimitExceeded855		);856857		let mut balances = BTreeMap::new();858		for data in &data {859			for owner in data.users.keys() {860				let balance = balances861					.entry(owner)862					.or_insert_with(|| <AccountBalance<T>>::get((collection.id, owner)));863				*balance = balance.checked_add(1).ok_or(ArithmeticError::Overflow)?;864865				ensure!(866					*balance <= collection.limits.account_token_ownership_limit(),867					<CommonError<T>>::AccountTokenLimitExceeded,868				);869			}870		}871872		for (i, token) in data.iter().enumerate() {873			let token_id = TokenId(first_token_id + i as u32 + 1);874			for (to, _) in token.users.iter() {875				<PalletStructure<T>>::check_nesting(876					sender.clone(),877					to,878					collection.id,879					token_id,880					nesting_budget,881				)?;882			}883		}884885		// =========886887		with_transaction(|| {888			for (i, data) in data.iter().enumerate() {889				let token_id = first_token_id + i as u32 + 1;890				<TotalSupply<T>>::insert((collection.id, token_id), totals[i]);891892				<TokenData<T>>::insert(893					(collection.id, token_id),894					ItemData {895						const_data: data.const_data.clone(),896					},897				);898899				for (user, amount) in data.users.iter() {900					if *amount == 0 {901						continue;902					}903					<Balance<T>>::insert((collection.id, token_id, &user), amount);904					<Owned<T>>::insert((collection.id, &user, TokenId(token_id)), true);905					<PalletStructure<T>>::nest_if_sent_to_token_unchecked(906						user,907						collection.id,908						TokenId(token_id),909					);910				}911912				if let Err(e) = Self::set_token_properties(913					collection,914					sender,915					TokenId(token_id),916					data.properties.clone().into_iter(),917					true,918					nesting_budget,919				) {920					return TransactionOutcome::Rollback(Err(e));921				}922			}923			TransactionOutcome::Commit(Ok(()))924		})?;925926		<TokensMinted<T>>::insert(collection.id, tokens_minted);927928		for (account, balance) in balances {929			<AccountBalance<T>>::insert((collection.id, account), balance);930		}931932		for (i, token) in data.into_iter().enumerate() {933			let token_id = first_token_id + i as u32 + 1;934935			for (user, amount) in token.users.into_iter() {936				if amount == 0 {937					continue;938				}939940				<PalletEvm<T>>::deposit_log(941					ERC20Events::Transfer {942						from: H160::default(),943						to: *user.as_eth(),944						value: amount.into(),945					}946					.to_log(T::EvmTokenAddressMapping::token_to_address(947						collection.id,948						TokenId(token_id),949					)),950				);951				<PalletEvm<T>>::deposit_log(952					ERC721Events::Transfer {953						from: H160::default(),954						to: *user.as_eth(),955						token_id: token_id.into(),956					}957					.to_log(collection_id_to_address(collection.id)),958				);959				<PalletCommon<T>>::deposit_event(CommonEvent::ItemCreated(960					collection.id,961					TokenId(token_id),962					user,963					amount,964				));965			}966		}967		Ok(())968	}969970	pub fn set_allowance_unchecked(971		collection: &RefungibleHandle<T>,972		sender: &T::CrossAccountId,973		spender: &T::CrossAccountId,974		token: TokenId,975		amount: u128,976	) {977		if amount == 0 {978			<Allowance<T>>::remove((collection.id, token, sender, spender));979		} else {980			<Allowance<T>>::insert((collection.id, token, sender, spender), amount);981		}982983		<PalletEvm<T>>::deposit_log(984			ERC20Events::Approval {985				owner: *sender.as_eth(),986				spender: *spender.as_eth(),987				value: amount.into(),988			}989			.to_log(T::EvmTokenAddressMapping::token_to_address(990				collection.id,991				token,992			)),993		);994		<PalletCommon<T>>::deposit_event(CommonEvent::Approved(995			collection.id,996			token,997			sender.clone(),998			spender.clone(),999			amount,1000		))1001	}10021003	/// Set allowance for the spender to `transfer` or `burn` sender's token pieces.1004	///1005	/// - `amount`: Amount of token pieces the spender is allowed to `transfer` or `burn.1006	pub fn set_allowance(1007		collection: &RefungibleHandle<T>,1008		sender: &T::CrossAccountId,1009		spender: &T::CrossAccountId,1010		token: TokenId,1011		amount: u128,1012	) -> DispatchResult {1013		if collection.permissions.access() == AccessMode::AllowList {1014			collection.check_allowlist(sender)?;1015			collection.check_allowlist(spender)?;1016		}10171018		<PalletCommon<T>>::ensure_correct_receiver(spender)?;10191020		if <Balance<T>>::get((collection.id, token, sender)) < amount {1021			ensure!(1022				collection.ignores_owned_amount(sender) && Self::token_exists(collection, token),1023				<CommonError<T>>::CantApproveMoreThanOwned1024			);1025		}10261027		// =========10281029		Self::set_allowance_unchecked(collection, sender, spender, token, amount);1030		Ok(())1031	}10321033	/// Returns allowance, which should be set after transaction1034	fn check_allowed(1035		collection: &RefungibleHandle<T>,1036		spender: &T::CrossAccountId,1037		from: &T::CrossAccountId,1038		token: TokenId,1039		amount: u128,1040		nesting_budget: &dyn Budget,1041	) -> Result<Option<u128>, DispatchError> {1042		if spender.conv_eq(from) {1043			return Ok(None);1044		}1045		if collection.permissions.access() == AccessMode::AllowList {1046			// `from`, `to` checked in [`transfer`]1047			collection.check_allowlist(spender)?;1048		}1049		if let Some(source) = T::CrossTokenAddressMapping::address_to_token(from) {1050			// TODO: should collection owner be allowed to perform this transfer?1051			ensure!(1052				<PalletStructure<T>>::check_indirectly_owned(1053					spender.clone(),1054					source.0,1055					source.1,1056					None,1057					nesting_budget1058				)?,1059				<CommonError<T>>::ApprovedValueTooLow,1060			);1061			return Ok(None);1062		}1063		let allowance =1064			<Allowance<T>>::get((collection.id, token, from, &spender)).checked_sub(amount);1065		if allowance.is_none() {1066			ensure!(1067				collection.ignores_allowance(spender),1068				<CommonError<T>>::ApprovedValueTooLow1069			);1070		}1071		Ok(allowance)1072	}10731074	/// Transfer RFT token pieces from one account to another.1075	///1076	/// Same as the [`transfer`] but spender doesn't needs to be an owner of the token pieces.1077	/// The owner should set allowance for the spender to transfer pieces.1078	///1079	/// [`transfer`]: struct.Pallet.html#method.transfer1080	pub fn transfer_from(1081		collection: &RefungibleHandle<T>,1082		spender: &T::CrossAccountId,1083		from: &T::CrossAccountId,1084		to: &T::CrossAccountId,1085		token: TokenId,1086		amount: u128,1087		nesting_budget: &dyn Budget,1088	) -> DispatchResult {1089		let allowance =1090			Self::check_allowed(collection, spender, from, token, amount, nesting_budget)?;10911092		// =========10931094		Self::transfer(collection, from, to, token, amount, nesting_budget)?;1095		if let Some(allowance) = allowance {1096			Self::set_allowance_unchecked(collection, from, spender, token, allowance);1097		}1098		Ok(())1099	}11001101	/// Burn RFT token pieces from the account.1102	///1103	/// Same as the [`burn`] but spender doesn't need to be an owner of the token pieces. The owner should1104	/// set allowance for the spender to burn pieces1105	///1106	/// [`burn`]: struct.Pallet.html#method.burn1107	pub fn burn_from(1108		collection: &RefungibleHandle<T>,1109		spender: &T::CrossAccountId,1110		from: &T::CrossAccountId,1111		token: TokenId,1112		amount: u128,1113		nesting_budget: &dyn Budget,1114	) -> DispatchResult {1115		let allowance =1116			Self::check_allowed(collection, spender, from, token, amount, nesting_budget)?;11171118		// =========11191120		Self::burn(collection, from, token, amount)?;1121		if let Some(allowance) = allowance {1122			Self::set_allowance_unchecked(collection, from, spender, token, allowance);1123		}1124		Ok(())1125	}11261127	/// Create RFT token.1128	///1129	/// The sender should be the owner/admin of the collection or collection should be configured1130	/// to allow public minting.1131	///1132	/// - `data`: Contains list of users who will become the owners of the token pieces and amount1133	///   of token pieces they will receive.1134	pub fn create_item(1135		collection: &RefungibleHandle<T>,1136		sender: &T::CrossAccountId,1137		data: CreateItemData<T>,1138		nesting_budget: &dyn Budget,1139	) -> DispatchResult {1140		Self::create_multiple_items(collection, sender, vec![data], nesting_budget)1141	}11421143	/// Repartition RFT token.1144	///1145	/// `repartition` will set token balance of the sender and total amount of token pieces.1146	/// Sender should own all of the token pieces. `repartition' could be done even if some1147	/// token pieces were burned before.1148	///1149	/// - `amount`: Total amount of token pieces that the token will have after `repartition`.1150	pub fn repartition(1151		collection: &RefungibleHandle<T>,1152		owner: &T::CrossAccountId,1153		token: TokenId,1154		amount: u128,1155	) -> DispatchResult {1156		ensure!(1157			amount <= MAX_REFUNGIBLE_PIECES,1158			<Error<T>>::WrongRefungiblePieces1159		);1160		ensure!(amount > 0, <CommonError<T>>::TokenValueTooLow);1161		// Ensure user owns all pieces1162		let total_pieces = Self::total_pieces(collection.id, token).unwrap_or(u128::MAX);1163		let balance = <Balance<T>>::get((collection.id, token, owner));1164		ensure!(1165			total_pieces == balance,1166			<Error<T>>::RepartitionWhileNotOwningAllPieces1167		);11681169		<Balance<T>>::insert((collection.id, token, owner), amount);1170		<TotalSupply<T>>::insert((collection.id, token), amount);11711172		if amount > total_pieces {1173			let mint_amount = amount - total_pieces;1174			<PalletEvm<T>>::deposit_log(1175				ERC20Events::Transfer {1176					from: H160::default(),1177					to: *owner.as_eth(),1178					value: mint_amount.into(),1179				}1180				.to_log(T::EvmTokenAddressMapping::token_to_address(1181					collection.id,1182					token,1183				)),1184			);1185			<PalletCommon<T>>::deposit_event(CommonEvent::ItemCreated(1186				collection.id,1187				token,1188				owner.clone(),1189				mint_amount,1190			));1191		} else if total_pieces > amount {1192			let burn_amount = total_pieces - amount;1193			<PalletEvm<T>>::deposit_log(1194				ERC20Events::Transfer {1195					from: *owner.as_eth(),1196					to: H160::default(),1197					value: burn_amount.into(),1198				}1199				.to_log(T::EvmTokenAddressMapping::token_to_address(1200					collection.id,1201					token,1202				)),1203			);1204			<PalletCommon<T>>::deposit_event(CommonEvent::ItemDestroyed(1205				collection.id,1206				token,1207				owner.clone(),1208				burn_amount,1209			));1210		}12111212		Ok(())1213	}12141215	fn token_owner(collection_id: CollectionId, token_id: TokenId) -> Option<T::CrossAccountId> {1216		let mut owner = None;1217		let mut count = 0;1218		for key in Balance::<T>::iter_key_prefix((collection_id, token_id)) {1219			count += 1;1220			if count > 1 {1221				return None;1222			}1223			owner = Some(key);1224		}1225		owner1226	}12271228	fn total_pieces(collection_id: CollectionId, token_id: TokenId) -> Option<u128> {1229		<TotalSupply<T>>::try_get((collection_id, token_id)).ok()1230	}12311232	pub fn set_collection_properties(1233		collection: &RefungibleHandle<T>,1234		sender: &T::CrossAccountId,1235		properties: Vec<Property>,1236	) -> DispatchResult {1237		<PalletCommon<T>>::set_collection_properties(collection, sender, properties)1238	}12391240	pub fn delete_collection_properties(1241		collection: &RefungibleHandle<T>,1242		sender: &T::CrossAccountId,1243		property_keys: Vec<PropertyKey>,1244	) -> DispatchResult {1245		<PalletCommon<T>>::delete_collection_properties(collection, sender, property_keys)1246	}12471248	pub fn set_token_property_permissions(1249		collection: &RefungibleHandle<T>,1250		sender: &T::CrossAccountId,1251		property_permissions: Vec<PropertyKeyPermission>,1252	) -> DispatchResult {1253		<PalletCommon<T>>::set_token_property_permissions(collection, sender, property_permissions)1254	}12551256	/// Returns 10 token in no particular order.1257	///1258	/// There is no direct way to get token holders in ascending order,1259	/// since `iter_prefix` returns values in no particular order.1260	/// Therefore, getting the 10 largest holders with a large value of holders1261	/// can lead to impact memory allocation + sorting with  `n * log (n)`.1262	pub fn token_owners(1263		collection_id: CollectionId,1264		token: TokenId,1265	) -> Option<Vec<T::CrossAccountId>> {1266		let res: Vec<T::CrossAccountId> = <Balance<T>>::iter_prefix((collection_id, token))1267			.map(|(owner, _amount)| owner)1268			.take(10)1269			.collect();12701271		if res.is_empty() {1272			None1273		} else {1274			Some(res)1275		}1276	}1277}