git.delta.rocks / unique-network / refs/commits / ddcf89abd283

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::{97	BoundedVec, ensure, fail, storage::with_transaction, transactional, pallet_prelude::ConstU32,98};99use pallet_evm::{account::CrossAccountId, Pallet as PalletEvm};100use pallet_evm_coder_substrate::WithRecorder;101use pallet_common::{102	CollectionHandle, CommonCollectionOperations,103	dispatch::CollectionDispatch,104	erc::static_property::{key, property_value_from_bytes},105	Error as CommonError,106	eth::collection_id_to_address,107	Event as CommonEvent, Pallet as PalletCommon,108};109use pallet_structure::Pallet as PalletStructure;110use scale_info::TypeInfo;111use sp_core::H160;112use sp_runtime::{ArithmeticError, DispatchError, DispatchResult, TransactionOutcome};113use sp_std::{vec::Vec, vec, collections::btree_map::BTreeMap};114use up_data_structs::{115	AccessMode, budget::Budget, CollectionId, CollectionMode, CollectionPropertiesVec,116	CreateCollectionData, CustomDataLimit, mapping::TokenAddressMapping, MAX_ITEMS_PER_BATCH,117	MAX_REFUNGIBLE_PIECES, Property, PropertyKey, PropertyKeyPermission, PropertyPermission,118	PropertyScope, PropertyValue, TokenId, TrySetProperty,119};120use frame_support::BoundedBTreeMap;121use derivative::Derivative;122123pub use pallet::*;124#[cfg(feature = "runtime-benchmarks")]125pub mod benchmarking;126pub mod common;127pub mod erc;128pub mod erc_token;129pub mod weights;130131#[derive(Derivative, Clone)]132pub struct CreateItemData<CrossAccountId> {133	#[derivative(Debug(format_with = "bounded::map_debug"))]134	pub users: BoundedBTreeMap<CrossAccountId, u128, ConstU32<MAX_ITEMS_PER_BATCH>>,135	#[derivative(Debug(format_with = "bounded::vec_debug"))]136	pub properties: CollectionPropertiesVec,137}138pub(crate) type SelfWeightOf<T> = <T as Config>::WeightInfo;139140/// Token data, stored independently from other data used to describe it141/// for the convenience of database access. Notably contains the token metadata.142#[struct_versioning::versioned(version = 2, upper)]143#[derive(Encode, Decode, Default, TypeInfo, MaxEncodedLen)]144#[deprecated(since = "0.2.0", note = "ItemData is no more contains usefull data")]145pub struct ItemData {146	pub const_data: BoundedVec<u8, CustomDataLimit>,147148	#[version(..2)]149	pub variable_data: BoundedVec<u8, CustomDataLimit>,150}151152#[frame_support::pallet]153pub mod pallet {154	use super::*;155	use frame_support::{156		Blake2_128, Blake2_128Concat, Twox64Concat, pallet_prelude::*, storage::Key,157		traits::StorageVersion,158	};159	use frame_system::pallet_prelude::*;160	use up_data_structs::{CollectionId, TokenId};161	use super::weights::WeightInfo;162163	#[pallet::error]164	pub enum Error<T> {165		/// Not Refungible item data used to mint in Refungible collection.166		NotRefungibleDataUsedToMintFungibleCollectionToken,167		/// Maximum refungibility exceeded.168		WrongRefungiblePieces,169		/// Refungible token can't be repartitioned by user who isn't owns all pieces.170		RepartitionWhileNotOwningAllPieces,171		/// Refungible token can't nest other tokens.172		RefungibleDisallowsNesting,173		/// Setting item properties is not allowed.174		SettingPropertiesNotAllowed,175	}176177	#[pallet::config]178	pub trait Config:179		frame_system::Config + pallet_common::Config + pallet_structure::Config180	{181		type WeightInfo: WeightInfo;182	}183184	const STORAGE_VERSION: StorageVersion = StorageVersion::new(2);185186	#[pallet::pallet]187	#[pallet::storage_version(STORAGE_VERSION)]188	#[pallet::generate_store(pub(super) trait Store)]189	pub struct Pallet<T>(_);190191	/// Total amount of minted tokens in a collection.192	#[pallet::storage]193	pub type TokensMinted<T: Config> =194		StorageMap<Hasher = Twox64Concat, Key = CollectionId, Value = u32, QueryKind = ValueQuery>;195196	/// Amount of tokens burnt in a collection.197	#[pallet::storage]198	pub type TokensBurnt<T: Config> =199		StorageMap<Hasher = Twox64Concat, Key = CollectionId, Value = u32, QueryKind = ValueQuery>;200201	/// Token data, used to partially describe a token.202	// TODO: remove203	#[pallet::storage]204	#[deprecated(since = "0.2.0", note = "ItemData is no more contains usefull data")]205	pub type TokenData<T: Config> = StorageNMap<206		Key = (Key<Twox64Concat, CollectionId>, Key<Twox64Concat, TokenId>),207		Value = ItemData,208		QueryKind = ValueQuery,209	>;210211	/// Amount of pieces a refungible token is split into.212	#[pallet::storage]213	#[pallet::getter(fn token_properties)]214	pub type TokenProperties<T: Config> = StorageNMap<215		Key = (Key<Twox64Concat, CollectionId>, Key<Twox64Concat, TokenId>),216		Value = up_data_structs::Properties,217		QueryKind = ValueQuery,218		OnEmpty = up_data_structs::TokenProperties,219	>;220221	/// Total amount of pieces for token222	#[pallet::storage]223	pub type TotalSupply<T: Config> = StorageNMap<224		Key = (Key<Twox64Concat, CollectionId>, Key<Twox64Concat, TokenId>),225		Value = u128,226		QueryKind = ValueQuery,227	>;228229	/// Used to enumerate tokens owned by account.230	#[pallet::storage]231	pub type Owned<T: Config> = StorageNMap<232		Key = (233			Key<Twox64Concat, CollectionId>,234			Key<Blake2_128Concat, T::CrossAccountId>,235			Key<Twox64Concat, TokenId>,236		),237		Value = bool,238		QueryKind = ValueQuery,239	>;240241	/// Amount of tokens (not pieces) partially owned by an account within a collection.242	#[pallet::storage]243	pub type AccountBalance<T: Config> = StorageNMap<244		Key = (245			Key<Twox64Concat, CollectionId>,246			// Owner247			Key<Blake2_128Concat, T::CrossAccountId>,248		),249		Value = u32,250		QueryKind = ValueQuery,251	>;252253	/// Amount of token pieces owned by account.254	#[pallet::storage]255	pub type Balance<T: Config> = StorageNMap<256		Key = (257			Key<Twox64Concat, CollectionId>,258			Key<Twox64Concat, TokenId>,259			// Owner260			Key<Blake2_128Concat, T::CrossAccountId>,261		),262		Value = u128,263		QueryKind = ValueQuery,264	>;265266	/// Allowance set by a token owner for another user to perform one of certain transactions on a number of pieces of a token.267	#[pallet::storage]268	pub type Allowance<T: Config> = StorageNMap<269		Key = (270			Key<Twox64Concat, CollectionId>,271			Key<Twox64Concat, TokenId>,272			// Owner273			Key<Blake2_128, T::CrossAccountId>,274			// Spender275			Key<Blake2_128Concat, T::CrossAccountId>,276		),277		Value = u128,278		QueryKind = ValueQuery,279	>;280281	#[pallet::hooks]282	impl<T: Config> Hooks<BlockNumberFor<T>> for Pallet<T> {283		fn on_runtime_upgrade() -> Weight {284			let storage_version = StorageVersion::get::<Pallet<T>>();285			if storage_version < StorageVersion::new(2) {286				<TokenData<T>>::remove_all(None);287			}288			StorageVersion::new(2).put::<Pallet<T>>();289290			0291		}292	}293}294295pub struct RefungibleHandle<T: Config>(pallet_common::CollectionHandle<T>);296impl<T: Config> RefungibleHandle<T> {297	pub fn cast(inner: pallet_common::CollectionHandle<T>) -> Self {298		Self(inner)299	}300	pub fn into_inner(self) -> pallet_common::CollectionHandle<T> {301		self.0302	}303	pub fn common_mut(&mut self) -> &mut pallet_common::CollectionHandle<T> {304		&mut self.0305	}306}307308impl<T: Config> Deref for RefungibleHandle<T> {309	type Target = pallet_common::CollectionHandle<T>;310311	fn deref(&self) -> &Self::Target {312		&self.0313	}314}315316impl<T: Config> WithRecorder<T> for RefungibleHandle<T> {317	fn recorder(&self) -> &pallet_evm_coder_substrate::SubstrateRecorder<T> {318		self.0.recorder()319	}320	fn into_recorder(self) -> pallet_evm_coder_substrate::SubstrateRecorder<T> {321		self.0.into_recorder()322	}323}324325impl<T: Config> Pallet<T> {326	/// Get number of RFT tokens in collection327	pub fn total_supply(collection: &RefungibleHandle<T>) -> u32 {328		<TokensMinted<T>>::get(collection.id) - <TokensBurnt<T>>::get(collection.id)329	}330331	/// Check that RFT token exists332	///333	/// - `token`: Token ID.334	pub fn token_exists(collection: &RefungibleHandle<T>, token: TokenId) -> bool {335		<TotalSupply<T>>::contains_key((collection.id, token))336	}337338	pub fn set_scoped_token_property(339		collection_id: CollectionId,340		token_id: TokenId,341		scope: PropertyScope,342		property: Property,343	) -> DispatchResult {344		TokenProperties::<T>::try_mutate((collection_id, token_id), |properties| {345			properties.try_scoped_set(scope, property.key, property.value)346		})347		.map_err(<CommonError<T>>::from)?;348349		Ok(())350	}351352	pub fn set_scoped_token_properties(353		collection_id: CollectionId,354		token_id: TokenId,355		scope: PropertyScope,356		properties: impl Iterator<Item = Property>,357	) -> DispatchResult {358		TokenProperties::<T>::try_mutate((collection_id, token_id), |stored_properties| {359			stored_properties.try_scoped_set_from_iter(scope, properties)360		})361		.map_err(<CommonError<T>>::from)?;362363		Ok(())364	}365}366367// unchecked calls skips any permission checks368impl<T: Config> Pallet<T> {369	/// Create RFT collection370	///371	/// `init_collection` will take non-refundable deposit for collection creation.372	///373	/// - `data`: Contains settings for collection limits and permissions.374	pub fn init_collection(375		owner: T::CrossAccountId,376		data: CreateCollectionData<T::AccountId>,377	) -> Result<CollectionId, DispatchError> {378		<PalletCommon<T>>::init_collection(owner, data, false)379	}380381	/// Destroy RFT collection382	///383	/// `destroy_collection` will throw error if collection contains any tokens.384	/// Only owner can destroy collection.385	pub fn destroy_collection(386		collection: RefungibleHandle<T>,387		sender: &T::CrossAccountId,388	) -> DispatchResult {389		let id = collection.id;390391		if Self::collection_has_tokens(id) {392			return Err(<CommonError<T>>::CantDestroyNotEmptyCollection.into());393		}394395		// =========396397		PalletCommon::destroy_collection(collection.0, sender)?;398399		<TokensMinted<T>>::remove(id);400		<TokensBurnt<T>>::remove(id);401		<TotalSupply<T>>::remove_prefix((id,), None);402		<Balance<T>>::remove_prefix((id,), None);403		<Allowance<T>>::remove_prefix((id,), None);404		<Owned<T>>::remove_prefix((id,), None);405		<AccountBalance<T>>::remove_prefix((id,), None);406		Ok(())407	}408409	fn collection_has_tokens(collection_id: CollectionId) -> bool {410		<TotalSupply<T>>::iter_prefix((collection_id,))411			.next()412			.is_some()413	}414415	pub fn burn_token_unchecked(416		collection: &RefungibleHandle<T>,417		owner: &T::CrossAccountId,418		token_id: TokenId,419	) -> DispatchResult {420		let burnt = <TokensBurnt<T>>::get(collection.id)421			.checked_add(1)422			.ok_or(ArithmeticError::Overflow)?;423424		<TokensBurnt<T>>::insert(collection.id, burnt);425		<TokenProperties<T>>::remove((collection.id, token_id));426		<TotalSupply<T>>::remove((collection.id, token_id));427		<Balance<T>>::remove_prefix((collection.id, token_id), None);428		<Allowance<T>>::remove_prefix((collection.id, token_id), None);429430		<PalletEvm<T>>::deposit_log(431			ERC721Events::Transfer {432				from: *owner.as_eth(),433				to: H160::default(),434				token_id: token_id.into(),435			}436			.to_log(collection_id_to_address(collection.id)),437		);438		Ok(())439	}440441	/// Burn RFT token pieces442	///443	/// `burn` will decrease total amount of token pieces and amount owned by sender.444	/// `burn` can be called even if there are multiple owners of the RFT token.445	/// If sender wouldn't have any pieces left after `burn` than she will stop being446	/// one of the owners of the token. If there is no account that owns any pieces of447	/// the token than token will be burned too.448	///449	/// - `amount`: Amount of token pieces to burn.450	/// - `token`: Token who's pieces should be burned451	/// - `collection`: Collection that contains the token452	pub fn burn(453		collection: &RefungibleHandle<T>,454		owner: &T::CrossAccountId,455		token: TokenId,456		amount: u128,457	) -> DispatchResult {458		let total_supply = <TotalSupply<T>>::get((collection.id, token))459			.checked_sub(amount)460			.ok_or(<CommonError<T>>::TokenValueTooLow)?;461462		// This was probally last owner of this token?463		if total_supply == 0 {464			// Ensure user actually owns this amount465			ensure!(466				<Balance<T>>::get((collection.id, token, owner)) == amount,467				<CommonError<T>>::TokenValueTooLow468			);469			let account_balance = <AccountBalance<T>>::get((collection.id, owner))470				.checked_sub(1)471				// Should not occur472				.ok_or(ArithmeticError::Underflow)?;473474			// =========475476			<Owned<T>>::remove((collection.id, owner, token));477			<PalletStructure<T>>::unnest_if_nested(owner, collection.id, token);478			<AccountBalance<T>>::insert((collection.id, owner), account_balance);479			Self::burn_token_unchecked(collection, owner, token)?;480			<PalletEvm<T>>::deposit_log(481				ERC20Events::Transfer {482					from: *owner.as_eth(),483					to: H160::default(),484					value: amount.into(),485				}486				.to_log(collection_id_to_address(collection.id)),487			);488			<PalletCommon<T>>::deposit_event(CommonEvent::ItemDestroyed(489				collection.id,490				token,491				owner.clone(),492				amount,493			));494			return Ok(());495		}496497		let balance = <Balance<T>>::get((collection.id, token, owner))498			.checked_sub(amount)499			.ok_or(<CommonError<T>>::TokenValueTooLow)?;500		let account_balance = if balance == 0 {501			<AccountBalance<T>>::get((collection.id, owner))502				.checked_sub(1)503				// Should not occur504				.ok_or(ArithmeticError::Underflow)?505		} else {506			0507		};508509		// =========510511		if balance == 0 {512			<Owned<T>>::remove((collection.id, owner, token));513			<PalletStructure<T>>::unnest_if_nested(owner, collection.id, token);514			<Balance<T>>::remove((collection.id, token, owner));515			<AccountBalance<T>>::insert((collection.id, owner), account_balance);516517			if let Some(user) = Self::token_owner(collection.id, token) {518				<PalletEvm<T>>::deposit_log(519					ERC721Events::Transfer {520						from: erc::ADDRESS_FOR_PARTIALLY_OWNED_TOKENS,521						to: *user.as_eth(),522						token_id: token.into(),523					}524					.to_log(collection_id_to_address(collection.id)),525				);526			}527		} else {528			<Balance<T>>::insert((collection.id, token, owner), balance);529		}530		<TotalSupply<T>>::insert((collection.id, token), total_supply);531532		<PalletEvm<T>>::deposit_log(533			ERC20Events::Transfer {534				from: *owner.as_eth(),535				to: H160::default(),536				value: amount.into(),537			}538			.to_log(T::EvmTokenAddressMapping::token_to_address(539				collection.id,540				token,541			)),542		);543		<PalletCommon<T>>::deposit_event(CommonEvent::ItemDestroyed(544			collection.id,545			token,546			owner.clone(),547			amount,548		));549		Ok(())550	}551552	#[transactional]553	fn modify_token_properties(554		collection: &RefungibleHandle<T>,555		sender: &T::CrossAccountId,556		token_id: TokenId,557		properties: impl Iterator<Item = (PropertyKey, Option<PropertyValue>)>,558		is_token_create: bool,559		nesting_budget: &dyn Budget,560	) -> DispatchResult {561		let is_collection_admin = || collection.is_owner_or_admin(sender);562		let is_token_owner = || -> Result<bool, DispatchError> {563			let balance = collection.balance(sender.clone(), token_id);564			let total_pieces: u128 =565				Self::total_pieces(collection.id, token_id).unwrap_or(u128::MAX);566			if balance != total_pieces {567				return Ok(false);568			}569570			let is_bundle_owner = <PalletStructure<T>>::check_indirectly_owned(571				sender.clone(),572				collection.id,573				token_id,574				None,575				nesting_budget,576			)?;577578			Ok(is_bundle_owner)579		};580581		for (key, value) in properties {582			let permission = <PalletCommon<T>>::property_permissions(collection.id)583				.get(&key)584				.cloned()585				.unwrap_or_else(PropertyPermission::none);586587			let is_property_exists = TokenProperties::<T>::get((collection.id, token_id))588				.get(&key)589				.is_some();590591			match permission {592				PropertyPermission { mutable: false, .. } if is_property_exists => {593					return Err(<CommonError<T>>::NoPermission.into());594				}595596				PropertyPermission {597					collection_admin,598					token_owner,599					..600				} => {601					//TODO: investigate threats during public minting.602					let is_token_create =603						is_token_create && (collection_admin || token_owner) && value.is_some();604					if !(is_token_create605						|| (collection_admin && is_collection_admin())606						|| (token_owner && is_token_owner()?))607					{608						fail!(<CommonError<T>>::NoPermission);609					}610				}611			}612613			match value {614				Some(value) => {615					<TokenProperties<T>>::try_mutate((collection.id, token_id), |properties| {616						properties.try_set(key.clone(), value)617					})618					.map_err(<CommonError<T>>::from)?;619620					<PalletCommon<T>>::deposit_event(CommonEvent::TokenPropertySet(621						collection.id,622						token_id,623						key,624					));625				}626				None => {627					<TokenProperties<T>>::try_mutate((collection.id, token_id), |properties| {628						properties.remove(&key)629					})630					.map_err(<CommonError<T>>::from)?;631632					<PalletCommon<T>>::deposit_event(CommonEvent::TokenPropertyDeleted(633						collection.id,634						token_id,635						key,636					));637				}638			}639		}640641		Ok(())642	}643644	pub fn set_token_properties(645		collection: &RefungibleHandle<T>,646		sender: &T::CrossAccountId,647		token_id: TokenId,648		properties: impl Iterator<Item = Property>,649		is_token_create: bool,650		nesting_budget: &dyn Budget,651	) -> DispatchResult {652		Self::modify_token_properties(653			collection,654			sender,655			token_id,656			properties.map(|p| (p.key, Some(p.value))),657			is_token_create,658			nesting_budget,659		)660	}661662	pub fn set_token_property(663		collection: &RefungibleHandle<T>,664		sender: &T::CrossAccountId,665		token_id: TokenId,666		property: Property,667		nesting_budget: &dyn Budget,668	) -> DispatchResult {669		let is_token_create = false;670671		Self::set_token_properties(672			collection,673			sender,674			token_id,675			[property].into_iter(),676			is_token_create,677			nesting_budget,678		)679	}680681	pub fn delete_token_properties(682		collection: &RefungibleHandle<T>,683		sender: &T::CrossAccountId,684		token_id: TokenId,685		property_keys: impl Iterator<Item = PropertyKey>,686		nesting_budget: &dyn Budget,687	) -> DispatchResult {688		let is_token_create = false;689690		Self::modify_token_properties(691			collection,692			sender,693			token_id,694			property_keys.into_iter().map(|key| (key, None)),695			is_token_create,696			nesting_budget,697		)698	}699700	pub fn delete_token_property(701		collection: &RefungibleHandle<T>,702		sender: &T::CrossAccountId,703		token_id: TokenId,704		property_key: PropertyKey,705		nesting_budget: &dyn Budget,706	) -> DispatchResult {707		Self::delete_token_properties(708			collection,709			sender,710			token_id,711			[property_key].into_iter(),712			nesting_budget,713		)714	}715716	/// Transfer RFT token pieces from one account to another.717	///718	/// If the sender is no longer owns any pieces after the `transfer` than she stops being an owner of the token.719	///720	/// - `from`: Owner of token pieces to transfer.721	/// - `to`: Recepient of transfered token pieces.722	/// - `amount`: Amount of token pieces to transfer.723	/// - `token`: Token whos pieces should be transfered724	/// - `collection`: Collection that contains the token725	pub fn transfer(726		collection: &RefungibleHandle<T>,727		from: &T::CrossAccountId,728		to: &T::CrossAccountId,729		token: TokenId,730		amount: u128,731		nesting_budget: &dyn Budget,732	) -> DispatchResult {733		ensure!(734			collection.limits.transfers_enabled(),735			<CommonError<T>>::TransferNotAllowed736		);737738		if collection.permissions.access() == AccessMode::AllowList {739			collection.check_allowlist(from)?;740			collection.check_allowlist(to)?;741		}742		<PalletCommon<T>>::ensure_correct_receiver(to)?;743744		let initial_balance_from = <Balance<T>>::get((collection.id, token, from));745		let updated_balance_from = initial_balance_from746			.checked_sub(amount)747			.ok_or(<CommonError<T>>::TokenValueTooLow)?;748		let mut create_target = false;749		let from_to_differ = from != to;750		let updated_balance_to = if from != to {751			let old_balance = <Balance<T>>::get((collection.id, token, to));752			if old_balance == 0 {753				create_target = true;754			}755			Some(756				old_balance757					.checked_add(amount)758					.ok_or(ArithmeticError::Overflow)?,759			)760		} else {761			None762		};763764		let account_balance_from = if updated_balance_from == 0 {765			Some(766				<AccountBalance<T>>::get((collection.id, from))767					.checked_sub(1)768					// Should not occur769					.ok_or(ArithmeticError::Underflow)?,770			)771		} else {772			None773		};774		// Account data is created in token, AccountBalance should be increased775		// But only if from != to as we shouldn't check overflow in this case776		let account_balance_to = if create_target && from_to_differ {777			let account_balance_to = <AccountBalance<T>>::get((collection.id, to))778				.checked_add(1)779				.ok_or(ArithmeticError::Overflow)?;780			ensure!(781				account_balance_to < collection.limits.account_token_ownership_limit(),782				<CommonError<T>>::AccountTokenLimitExceeded,783			);784785			Some(account_balance_to)786		} else {787			None788		};789790		// =========791792		<PalletStructure<T>>::nest_if_sent_to_token(793			from.clone(),794			to,795			collection.id,796			token,797			nesting_budget,798		)?;799800		if let Some(updated_balance_to) = updated_balance_to {801			// from != to802			if updated_balance_from == 0 {803				<Balance<T>>::remove((collection.id, token, from));804				<PalletStructure<T>>::unnest_if_nested(from, collection.id, token);805			} else {806				<Balance<T>>::insert((collection.id, token, from), updated_balance_from);807			}808			<Balance<T>>::insert((collection.id, token, to), updated_balance_to);809			if let Some(account_balance_from) = account_balance_from {810				<AccountBalance<T>>::insert((collection.id, from), account_balance_from);811				<Owned<T>>::remove((collection.id, from, token));812			}813			if let Some(account_balance_to) = account_balance_to {814				<AccountBalance<T>>::insert((collection.id, to), account_balance_to);815				<Owned<T>>::insert((collection.id, to, token), true);816			}817		}818819		<PalletEvm<T>>::deposit_log(820			ERC20Events::Transfer {821				from: *from.as_eth(),822				to: *to.as_eth(),823				value: amount.into(),824			}825			.to_log(T::EvmTokenAddressMapping::token_to_address(826				collection.id,827				token,828			)),829		);830831		<PalletCommon<T>>::deposit_event(CommonEvent::Transfer(832			collection.id,833			token,834			from.clone(),835			to.clone(),836			amount,837		));838839		let total_supply = <TotalSupply<T>>::get((collection.id, token));840841		if amount == total_supply {842			// if token was fully owned by `from` and will be fully owned by `to` after transfer843			<PalletEvm<T>>::deposit_log(844				ERC721Events::Transfer {845					from: *from.as_eth(),846					to: *to.as_eth(),847					token_id: token.into(),848				}849				.to_log(collection_id_to_address(collection.id)),850			);851		} else if let Some(updated_balance_to) = updated_balance_to {852			// if `from` not equals `to`. This condition is needed to avoid sending event853			// when `from` fully owns token and sends part of token pieces to itself.854			if initial_balance_from == total_supply {855				// if token was fully owned by `from` and will be only partially owned by `to`856				// and `from` after transfer857				<PalletEvm<T>>::deposit_log(858					ERC721Events::Transfer {859						from: *from.as_eth(),860						to: erc::ADDRESS_FOR_PARTIALLY_OWNED_TOKENS,861						token_id: token.into(),862					}863					.to_log(collection_id_to_address(collection.id)),864				);865			} else if updated_balance_to == total_supply {866				// if token was partially owned by `from` and will be fully owned by `to` after transfer867				<PalletEvm<T>>::deposit_log(868					ERC721Events::Transfer {869						from: erc::ADDRESS_FOR_PARTIALLY_OWNED_TOKENS,870						to: *to.as_eth(),871						token_id: token.into(),872					}873					.to_log(collection_id_to_address(collection.id)),874				);875			}876		}877878		Ok(())879	}880881	/// Batched operation to create multiple RFT tokens.882	///883	/// Same as `create_item` but creates multiple tokens.884	///885	/// - `data`: Same as 'data` in `create_item` but contains data for multiple tokens.886	pub fn create_multiple_items(887		collection: &RefungibleHandle<T>,888		sender: &T::CrossAccountId,889		data: Vec<CreateItemData<T::CrossAccountId>>,890		nesting_budget: &dyn Budget,891	) -> DispatchResult {892		if !collection.is_owner_or_admin(sender) {893			ensure!(894				collection.permissions.mint_mode(),895				<CommonError<T>>::PublicMintingNotAllowed896			);897			collection.check_allowlist(sender)?;898899			for item in data.iter() {900				for user in item.users.keys() {901					collection.check_allowlist(user)?;902				}903			}904		}905906		for item in data.iter() {907			for (owner, _) in item.users.iter() {908				<PalletCommon<T>>::ensure_correct_receiver(owner)?;909			}910		}911912		// Total pieces per tokens913		let totals = data914			.iter()915			.map(|data| {916				Ok(data917					.users918					.iter()919					.map(|u| u.1)920					.try_fold(0u128, |acc, v| acc.checked_add(*v))921					.ok_or(ArithmeticError::Overflow)?)922			})923			.collect::<Result<Vec<_>, DispatchError>>()?;924		for total in &totals {925			ensure!(926				*total <= MAX_REFUNGIBLE_PIECES,927				<Error<T>>::WrongRefungiblePieces928			);929		}930931		let first_token_id = <TokensMinted<T>>::get(collection.id);932		let tokens_minted = first_token_id933			.checked_add(data.len() as u32)934			.ok_or(ArithmeticError::Overflow)?;935		ensure!(936			tokens_minted < collection.limits.token_limit(),937			<CommonError<T>>::CollectionTokenLimitExceeded938		);939940		let mut balances = BTreeMap::new();941		for data in &data {942			for owner in data.users.keys() {943				let balance = balances944					.entry(owner)945					.or_insert_with(|| <AccountBalance<T>>::get((collection.id, owner)));946				*balance = balance.checked_add(1).ok_or(ArithmeticError::Overflow)?;947948				ensure!(949					*balance <= collection.limits.account_token_ownership_limit(),950					<CommonError<T>>::AccountTokenLimitExceeded,951				);952			}953		}954955		for (i, token) in data.iter().enumerate() {956			let token_id = TokenId(first_token_id + i as u32 + 1);957			for (to, _) in token.users.iter() {958				<PalletStructure<T>>::check_nesting(959					sender.clone(),960					to,961					collection.id,962					token_id,963					nesting_budget,964				)?;965			}966		}967968		// =========969970		with_transaction(|| {971			for (i, data) in data.iter().enumerate() {972				let token_id = first_token_id + i as u32 + 1;973				<TotalSupply<T>>::insert((collection.id, token_id), totals[i]);974975				for (user, amount) in data.users.iter() {976					if *amount == 0 {977						continue;978					}979					<Balance<T>>::insert((collection.id, token_id, &user), amount);980					<Owned<T>>::insert((collection.id, &user, TokenId(token_id)), true);981					<PalletStructure<T>>::nest_if_sent_to_token_unchecked(982						user,983						collection.id,984						TokenId(token_id),985					);986				}987988				if let Err(e) = Self::set_token_properties(989					collection,990					sender,991					TokenId(token_id),992					data.properties.clone().into_iter(),993					true,994					nesting_budget,995				) {996					return TransactionOutcome::Rollback(Err(e));997				}998			}999			TransactionOutcome::Commit(Ok(()))1000		})?;10011002		<TokensMinted<T>>::insert(collection.id, tokens_minted);10031004		for (account, balance) in balances {1005			<AccountBalance<T>>::insert((collection.id, account), balance);1006		}10071008		for (i, token) in data.into_iter().enumerate() {1009			let token_id = first_token_id + i as u32 + 1;10101011			let receivers = token1012				.users1013				.into_iter()1014				.filter(|(_, amount)| *amount > 0)1015				.collect::<Vec<_>>();10161017			if let [(user, _)] = receivers.as_slice() {1018				// if there is exactly one receiver1019				<PalletEvm<T>>::deposit_log(1020					ERC721Events::Transfer {1021						from: H160::default(),1022						to: *user.as_eth(),1023						token_id: token_id.into(),1024					}1025					.to_log(collection_id_to_address(collection.id)),1026				);1027			} else if let [_, ..] = receivers.as_slice() {1028				// if there is more than one receiver1029				<PalletEvm<T>>::deposit_log(1030					ERC721Events::Transfer {1031						from: H160::default(),1032						to: erc::ADDRESS_FOR_PARTIALLY_OWNED_TOKENS,1033						token_id: token_id.into(),1034					}1035					.to_log(collection_id_to_address(collection.id)),1036				);1037			}10381039			for (user, amount) in receivers.into_iter() {1040				<PalletEvm<T>>::deposit_log(1041					ERC20Events::Transfer {1042						from: H160::default(),1043						to: *user.as_eth(),1044						value: amount.into(),1045					}1046					.to_log(T::EvmTokenAddressMapping::token_to_address(1047						collection.id,1048						TokenId(token_id),1049					)),1050				);1051				<PalletCommon<T>>::deposit_event(CommonEvent::ItemCreated(1052					collection.id,1053					TokenId(token_id),1054					user,1055					amount,1056				));1057			}1058		}1059		Ok(())1060	}10611062	pub fn set_allowance_unchecked(1063		collection: &RefungibleHandle<T>,1064		sender: &T::CrossAccountId,1065		spender: &T::CrossAccountId,1066		token: TokenId,1067		amount: u128,1068	) {1069		if amount == 0 {1070			<Allowance<T>>::remove((collection.id, token, sender, spender));1071		} else {1072			<Allowance<T>>::insert((collection.id, token, sender, spender), amount);1073		}10741075		<PalletEvm<T>>::deposit_log(1076			ERC20Events::Approval {1077				owner: *sender.as_eth(),1078				spender: *spender.as_eth(),1079				value: amount.into(),1080			}1081			.to_log(T::EvmTokenAddressMapping::token_to_address(1082				collection.id,1083				token,1084			)),1085		);1086		<PalletCommon<T>>::deposit_event(CommonEvent::Approved(1087			collection.id,1088			token,1089			sender.clone(),1090			spender.clone(),1091			amount,1092		))1093	}10941095	/// Set allowance for the spender to `transfer` or `burn` sender's token pieces.1096	///1097	/// - `amount`: Amount of token pieces the spender is allowed to `transfer` or `burn.1098	pub fn set_allowance(1099		collection: &RefungibleHandle<T>,1100		sender: &T::CrossAccountId,1101		spender: &T::CrossAccountId,1102		token: TokenId,1103		amount: u128,1104	) -> DispatchResult {1105		if collection.permissions.access() == AccessMode::AllowList {1106			collection.check_allowlist(sender)?;1107			collection.check_allowlist(spender)?;1108		}11091110		<PalletCommon<T>>::ensure_correct_receiver(spender)?;11111112		if <Balance<T>>::get((collection.id, token, sender)) < amount {1113			ensure!(1114				collection.ignores_owned_amount(sender) && Self::token_exists(collection, token),1115				<CommonError<T>>::CantApproveMoreThanOwned1116			);1117		}11181119		// =========11201121		Self::set_allowance_unchecked(collection, sender, spender, token, amount);1122		Ok(())1123	}11241125	/// Returns allowance, which should be set after transaction1126	fn check_allowed(1127		collection: &RefungibleHandle<T>,1128		spender: &T::CrossAccountId,1129		from: &T::CrossAccountId,1130		token: TokenId,1131		amount: u128,1132		nesting_budget: &dyn Budget,1133	) -> Result<Option<u128>, DispatchError> {1134		if spender.conv_eq(from) {1135			return Ok(None);1136		}1137		if collection.permissions.access() == AccessMode::AllowList {1138			// `from`, `to` checked in [`transfer`]1139			collection.check_allowlist(spender)?;1140		}1141		if let Some(source) = T::CrossTokenAddressMapping::address_to_token(from) {1142			// TODO: should collection owner be allowed to perform this transfer?1143			ensure!(1144				<PalletStructure<T>>::check_indirectly_owned(1145					spender.clone(),1146					source.0,1147					source.1,1148					None,1149					nesting_budget1150				)?,1151				<CommonError<T>>::ApprovedValueTooLow,1152			);1153			return Ok(None);1154		}1155		let allowance =1156			<Allowance<T>>::get((collection.id, token, from, &spender)).checked_sub(amount);1157		if allowance.is_none() {1158			ensure!(1159				collection.ignores_allowance(spender),1160				<CommonError<T>>::ApprovedValueTooLow1161			);1162		}1163		Ok(allowance)1164	}11651166	/// Transfer RFT token pieces from one account to another.1167	///1168	/// Same as the [`transfer`] but spender doesn't needs to be an owner of the token pieces.1169	/// The owner should set allowance for the spender to transfer pieces.1170	///1171	/// [`transfer`]: struct.Pallet.html#method.transfer1172	pub fn transfer_from(1173		collection: &RefungibleHandle<T>,1174		spender: &T::CrossAccountId,1175		from: &T::CrossAccountId,1176		to: &T::CrossAccountId,1177		token: TokenId,1178		amount: u128,1179		nesting_budget: &dyn Budget,1180	) -> DispatchResult {1181		let allowance =1182			Self::check_allowed(collection, spender, from, token, amount, nesting_budget)?;11831184		// =========11851186		Self::transfer(collection, from, to, token, amount, nesting_budget)?;1187		if let Some(allowance) = allowance {1188			Self::set_allowance_unchecked(collection, from, spender, token, allowance);1189		}1190		Ok(())1191	}11921193	/// Burn RFT token pieces from the account.1194	///1195	/// Same as the [`burn`] but spender doesn't need to be an owner of the token pieces. The owner should1196	/// set allowance for the spender to burn pieces1197	///1198	/// [`burn`]: struct.Pallet.html#method.burn1199	pub fn burn_from(1200		collection: &RefungibleHandle<T>,1201		spender: &T::CrossAccountId,1202		from: &T::CrossAccountId,1203		token: TokenId,1204		amount: u128,1205		nesting_budget: &dyn Budget,1206	) -> DispatchResult {1207		let allowance =1208			Self::check_allowed(collection, spender, from, token, amount, nesting_budget)?;12091210		// =========12111212		Self::burn(collection, from, token, amount)?;1213		if let Some(allowance) = allowance {1214			Self::set_allowance_unchecked(collection, from, spender, token, allowance);1215		}1216		Ok(())1217	}12181219	/// Create RFT token.1220	///1221	/// The sender should be the owner/admin of the collection or collection should be configured1222	/// to allow public minting.1223	///1224	/// - `data`: Contains list of users who will become the owners of the token pieces and amount1225	///   of token pieces they will receive.1226	pub fn create_item(1227		collection: &RefungibleHandle<T>,1228		sender: &T::CrossAccountId,1229		data: CreateItemData<T::CrossAccountId>,1230		nesting_budget: &dyn Budget,1231	) -> DispatchResult {1232		Self::create_multiple_items(collection, sender, vec![data], nesting_budget)1233	}12341235	/// Repartition RFT token.1236	///1237	/// `repartition` will set token balance of the sender and total amount of token pieces.1238	/// Sender should own all of the token pieces. `repartition' could be done even if some1239	/// token pieces were burned before.1240	///1241	/// - `amount`: Total amount of token pieces that the token will have after `repartition`.1242	pub fn repartition(1243		collection: &RefungibleHandle<T>,1244		owner: &T::CrossAccountId,1245		token: TokenId,1246		amount: u128,1247	) -> DispatchResult {1248		ensure!(1249			amount <= MAX_REFUNGIBLE_PIECES,1250			<Error<T>>::WrongRefungiblePieces1251		);1252		ensure!(amount > 0, <CommonError<T>>::TokenValueTooLow);1253		// Ensure user owns all pieces1254		let total_pieces = Self::total_pieces(collection.id, token).unwrap_or(u128::MAX);1255		let balance = <Balance<T>>::get((collection.id, token, owner));1256		ensure!(1257			total_pieces == balance,1258			<Error<T>>::RepartitionWhileNotOwningAllPieces1259		);12601261		<Balance<T>>::insert((collection.id, token, owner), amount);1262		<TotalSupply<T>>::insert((collection.id, token), amount);12631264		if amount > total_pieces {1265			let mint_amount = amount - total_pieces;1266			<PalletEvm<T>>::deposit_log(1267				ERC20Events::Transfer {1268					from: H160::default(),1269					to: *owner.as_eth(),1270					value: mint_amount.into(),1271				}1272				.to_log(T::EvmTokenAddressMapping::token_to_address(1273					collection.id,1274					token,1275				)),1276			);1277			<PalletCommon<T>>::deposit_event(CommonEvent::ItemCreated(1278				collection.id,1279				token,1280				owner.clone(),1281				mint_amount,1282			));1283		} else if total_pieces > amount {1284			let burn_amount = total_pieces - amount;1285			<PalletEvm<T>>::deposit_log(1286				ERC20Events::Transfer {1287					from: *owner.as_eth(),1288					to: H160::default(),1289					value: burn_amount.into(),1290				}1291				.to_log(T::EvmTokenAddressMapping::token_to_address(1292					collection.id,1293					token,1294				)),1295			);1296			<PalletCommon<T>>::deposit_event(CommonEvent::ItemDestroyed(1297				collection.id,1298				token,1299				owner.clone(),1300				burn_amount,1301			));1302		}13031304		Ok(())1305	}13061307	fn token_owner(collection_id: CollectionId, token_id: TokenId) -> Option<T::CrossAccountId> {1308		let mut owner = None;1309		let mut count = 0;1310		for key in Balance::<T>::iter_key_prefix((collection_id, token_id)) {1311			count += 1;1312			if count > 1 {1313				return None;1314			}1315			owner = Some(key);1316		}1317		owner1318	}13191320	fn total_pieces(collection_id: CollectionId, token_id: TokenId) -> Option<u128> {1321		<TotalSupply<T>>::try_get((collection_id, token_id)).ok()1322	}13231324	pub fn set_collection_properties(1325		collection: &RefungibleHandle<T>,1326		sender: &T::CrossAccountId,1327		properties: Vec<Property>,1328	) -> DispatchResult {1329		<PalletCommon<T>>::set_collection_properties(collection, sender, properties)1330	}13311332	pub fn delete_collection_properties(1333		collection: &RefungibleHandle<T>,1334		sender: &T::CrossAccountId,1335		property_keys: Vec<PropertyKey>,1336	) -> DispatchResult {1337		<PalletCommon<T>>::delete_collection_properties(collection, sender, property_keys)1338	}13391340	pub fn set_token_property_permissions(1341		collection: &RefungibleHandle<T>,1342		sender: &T::CrossAccountId,1343		property_permissions: Vec<PropertyKeyPermission>,1344	) -> DispatchResult {1345		<PalletCommon<T>>::set_token_property_permissions(collection, sender, property_permissions)1346	}13471348	pub fn set_scoped_token_property_permissions(1349		collection: &RefungibleHandle<T>,1350		sender: &T::CrossAccountId,1351		scope: PropertyScope,1352		property_permissions: Vec<PropertyKeyPermission>,1353	) -> DispatchResult {1354		<PalletCommon<T>>::set_scoped_token_property_permissions(1355			collection,1356			sender,1357			scope,1358			property_permissions,1359		)1360	}13611362	/// Returns 10 token in no particular order.1363	///1364	/// There is no direct way to get token holders in ascending order,1365	/// since `iter_prefix` returns values in no particular order.1366	/// Therefore, getting the 10 largest holders with a large value of holders1367	/// can lead to impact memory allocation + sorting with  `n * log (n)`.1368	pub fn token_owners(1369		collection_id: CollectionId,1370		token: TokenId,1371	) -> Option<Vec<T::CrossAccountId>> {1372		let res: Vec<T::CrossAccountId> = <Balance<T>>::iter_prefix((collection_id, token))1373			.map(|(owner, _amount)| owner)1374			.take(10)1375			.collect();13761377		if res.is_empty() {1378			None1379		} else {1380			Some(res)1381		}1382	}13831384	/// Sets the NFT token as a parent for the RFT token1385	///1386	/// Throws if `sender` is not the owner of the NFT token.1387	/// Throws if `sender` is not the owner of all of the RFT token pieces.1388	pub fn set_parent_nft(1389		collection: &RefungibleHandle<T>,1390		rft_token_id: TokenId,1391		sender: T::CrossAccountId,1392		nft_collection: CollectionId,1393		nft_token: TokenId,1394	) -> DispatchResult {1395		let handle = <CollectionHandle<T>>::try_get(nft_collection)?;1396		if handle.mode != CollectionMode::NFT {1397			return Err("Only NFT token could be parent to RFT".into());1398		}1399		let dispatch = T::CollectionDispatch::dispatch(handle);1400		let dispatch = dispatch.as_dyn();14011402		let owner = dispatch.token_owner(nft_token).ok_or("owner not found")?;1403		if owner != sender {1404			return Err("Only owned token could be set as parent".into());1405		}14061407		let nft_token_address =1408			T::CrossTokenAddressMapping::token_to_address(nft_collection, nft_token);14091410		Self::set_parent_nft_unchecked(collection, rft_token_id, sender, nft_token_address)1411	}14121413	/// Sets the NFT token as a parent for the RFT token1414	///1415	/// `sender` should be the owner of the NFT token.1416	/// Throws if `sender` is not the owner of all of the RFT token pieces.1417	pub fn set_parent_nft_unchecked(1418		collection: &RefungibleHandle<T>,1419		rft_token_id: TokenId,1420		sender: T::CrossAccountId,1421		nft_token_address: T::CrossAccountId,1422	) -> DispatchResult {1423		let owner_balance = <Balance<T>>::get((collection.id, rft_token_id, &sender));1424		let total_supply = <TotalSupply<T>>::get((collection.id, rft_token_id));1425		if total_supply != owner_balance {1426			return Err("token has multiple owners".into());1427		}14281429		let parent_nft_property_key = key::parent_nft();14301431		let parent_nft_property_value =1432			property_value_from_bytes(&nft_token_address.as_eth().to_fixed_bytes())1433				.expect("address should fit in value length limit");14341435		<Pallet<T>>::set_scoped_token_property(1436			collection.id,1437			rft_token_id,1438			PropertyScope::Eth,1439			Property {1440				key: parent_nft_property_key,1441				value: parent_nft_property_value,1442			},1443		)?;14441445		Ok(())1446	}1447}