git.delta.rocks / unique-network / refs/commits / c8ad2c279e20

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 derivative::Derivative;96use evm_coder::ToLog;97use frame_support::{98	BoundedBTreeMap, BoundedVec, ensure, fail, storage::with_transaction, transactional,99	pallet_prelude::ConstU32,100};101use pallet_evm::{account::CrossAccountId, Pallet as PalletEvm};102use pallet_evm_coder_substrate::WithRecorder;103use pallet_common::{104	CommonCollectionOperations, Error as CommonError, eth::collection_id_to_address,105	Event as CommonEvent, Pallet as PalletCommon,106};107use pallet_structure::Pallet as PalletStructure;108use scale_info::TypeInfo;109use sp_core::H160;110use sp_runtime::{ArithmeticError, DispatchError, DispatchResult, TransactionOutcome};111use sp_std::{vec::Vec, vec, collections::btree_map::BTreeMap};112use up_data_structs::{113	AccessMode, budget::Budget, CollectionId, CollectionFlags, CollectionPropertiesVec,114	CreateCollectionData, CustomDataLimit, mapping::TokenAddressMapping, MAX_ITEMS_PER_BATCH,115	MAX_REFUNGIBLE_PIECES, Property, PropertyKey, PropertyKeyPermission, PropertyPermission,116	PropertyScope, PropertyValue, TokenId, TrySetProperty,117};118119pub use pallet::*;120#[cfg(feature = "runtime-benchmarks")]121pub mod benchmarking;122pub mod common;123pub mod erc;124pub mod erc_token;125pub mod weights;126127#[derive(Derivative, Clone)]128pub struct CreateItemData<CrossAccountId> {129	#[derivative(Debug(format_with = "bounded::map_debug"))]130	pub users: BoundedBTreeMap<CrossAccountId, u128, ConstU32<MAX_ITEMS_PER_BATCH>>,131	#[derivative(Debug(format_with = "bounded::vec_debug"))]132	pub properties: CollectionPropertiesVec,133}134pub(crate) type SelfWeightOf<T> = <T as Config>::WeightInfo;135136/// Token data, stored independently from other data used to describe it137/// for the convenience of database access. Notably contains the token metadata.138#[struct_versioning::versioned(version = 2, upper)]139#[derive(Encode, Decode, Default, TypeInfo, MaxEncodedLen)]140pub struct ItemData {141	pub const_data: BoundedVec<u8, CustomDataLimit>,142143	#[version(..2)]144	pub variable_data: BoundedVec<u8, CustomDataLimit>,145}146147#[frame_support::pallet]148pub mod pallet {149	use super::*;150	use frame_support::{151		Blake2_128, Blake2_128Concat, Twox64Concat, pallet_prelude::*, storage::Key,152		traits::StorageVersion,153	};154	use frame_system::pallet_prelude::*;155	use up_data_structs::{CollectionId, TokenId};156	use super::weights::WeightInfo;157158	#[pallet::error]159	pub enum Error<T> {160		/// Not Refungible item data used to mint in Refungible collection.161		NotRefungibleDataUsedToMintFungibleCollectionToken,162		/// Maximum refungibility exceeded.163		WrongRefungiblePieces,164		/// Refungible token can't be repartitioned by user who isn't owns all pieces.165		RepartitionWhileNotOwningAllPieces,166		/// Refungible token can't nest other tokens.167		RefungibleDisallowsNesting,168		/// Setting item properties is not allowed.169		SettingPropertiesNotAllowed,170	}171172	#[pallet::config]173	pub trait Config:174		frame_system::Config + pallet_common::Config + pallet_structure::Config175	{176		type WeightInfo: WeightInfo;177	}178179	const STORAGE_VERSION: StorageVersion = StorageVersion::new(2);180181	#[pallet::pallet]182	#[pallet::storage_version(STORAGE_VERSION)]183	#[pallet::generate_store(pub(super) trait Store)]184	pub struct Pallet<T>(_);185186	/// Total amount of minted tokens in a collection.187	#[pallet::storage]188	pub type TokensMinted<T: Config> =189		StorageMap<Hasher = Twox64Concat, Key = CollectionId, Value = u32, QueryKind = ValueQuery>;190191	/// Amount of tokens burnt in a collection.192	#[pallet::storage]193	pub type TokensBurnt<T: Config> =194		StorageMap<Hasher = Twox64Concat, Key = CollectionId, Value = u32, QueryKind = ValueQuery>;195196	/// Token data, used to partially describe a token.197	// TODO: remove198	#[pallet::storage]199	#[deprecated(since = "0.2.0", note = "ItemData is no more contains usefull data")]200	pub type TokenData<T: Config> = StorageNMap<201		Key = (Key<Twox64Concat, CollectionId>, Key<Twox64Concat, TokenId>),202		Value = ItemData,203		QueryKind = ValueQuery,204	>;205206	/// Amount of pieces a refungible token is split into.207	#[pallet::storage]208	#[pallet::getter(fn token_properties)]209	pub type TokenProperties<T: Config> = StorageNMap<210		Key = (Key<Twox64Concat, CollectionId>, Key<Twox64Concat, TokenId>),211		Value = up_data_structs::Properties,212		QueryKind = ValueQuery,213		OnEmpty = up_data_structs::TokenProperties,214	>;215216	/// Total amount of pieces for token217	#[pallet::storage]218	pub type TotalSupply<T: Config> = StorageNMap<219		Key = (Key<Twox64Concat, CollectionId>, Key<Twox64Concat, TokenId>),220		Value = u128,221		QueryKind = ValueQuery,222	>;223224	/// Used to enumerate tokens owned by account.225	#[pallet::storage]226	pub type Owned<T: Config> = StorageNMap<227		Key = (228			Key<Twox64Concat, CollectionId>,229			Key<Blake2_128Concat, T::CrossAccountId>,230			Key<Twox64Concat, TokenId>,231		),232		Value = bool,233		QueryKind = ValueQuery,234	>;235236	/// Amount of tokens (not pieces) partially owned by an account within a collection.237	#[pallet::storage]238	pub type AccountBalance<T: Config> = StorageNMap<239		Key = (240			Key<Twox64Concat, CollectionId>,241			// Owner242			Key<Blake2_128Concat, T::CrossAccountId>,243		),244		Value = u32,245		QueryKind = ValueQuery,246	>;247248	/// Amount of token pieces owned by account.249	#[pallet::storage]250	pub type Balance<T: Config> = StorageNMap<251		Key = (252			Key<Twox64Concat, CollectionId>,253			Key<Twox64Concat, TokenId>,254			// Owner255			Key<Blake2_128Concat, T::CrossAccountId>,256		),257		Value = u128,258		QueryKind = ValueQuery,259	>;260261	/// Allowance set by a token owner for another user to perform one of certain transactions on a number of pieces of a token.262	#[pallet::storage]263	pub type Allowance<T: Config> = StorageNMap<264		Key = (265			Key<Twox64Concat, CollectionId>,266			Key<Twox64Concat, TokenId>,267			// Owner268			Key<Blake2_128, T::CrossAccountId>,269			// Spender270			Key<Blake2_128Concat, T::CrossAccountId>,271		),272		Value = u128,273		QueryKind = ValueQuery,274	>;275276	#[pallet::hooks]277	impl<T: Config> Hooks<BlockNumberFor<T>> for Pallet<T> {278		fn on_runtime_upgrade() -> Weight {279			let storage_version = StorageVersion::get::<Pallet<T>>();280			if storage_version < StorageVersion::new(2) {281				#[allow(deprecated)]282				let _ = <TokenData<T>>::clear(u32::MAX, None);283			}284			StorageVersion::new(2).put::<Pallet<T>>();285286			Weight::zero()287		}288	}289}290291pub struct RefungibleHandle<T: Config>(pallet_common::CollectionHandle<T>);292impl<T: Config> RefungibleHandle<T> {293	pub fn cast(inner: pallet_common::CollectionHandle<T>) -> Self {294		Self(inner)295	}296	pub fn into_inner(self) -> pallet_common::CollectionHandle<T> {297		self.0298	}299	pub fn common_mut(&mut self) -> &mut pallet_common::CollectionHandle<T> {300		&mut self.0301	}302}303304impl<T: Config> Deref for RefungibleHandle<T> {305	type Target = pallet_common::CollectionHandle<T>;306307	fn deref(&self) -> &Self::Target {308		&self.0309	}310}311312impl<T: Config> WithRecorder<T> for RefungibleHandle<T> {313	fn recorder(&self) -> &pallet_evm_coder_substrate::SubstrateRecorder<T> {314		self.0.recorder()315	}316	fn into_recorder(self) -> pallet_evm_coder_substrate::SubstrateRecorder<T> {317		self.0.into_recorder()318	}319}320321impl<T: Config> Pallet<T> {322	/// Get number of RFT tokens in collection323	pub fn total_supply(collection: &RefungibleHandle<T>) -> u32 {324		<TokensMinted<T>>::get(collection.id) - <TokensBurnt<T>>::get(collection.id)325	}326327	/// Check that RFT token exists328	///329	/// - `token`: Token ID.330	pub fn token_exists(collection: &RefungibleHandle<T>, token: TokenId) -> bool {331		<TotalSupply<T>>::contains_key((collection.id, token))332	}333334	pub fn set_scoped_token_property(335		collection_id: CollectionId,336		token_id: TokenId,337		scope: PropertyScope,338		property: Property,339	) -> DispatchResult {340		TokenProperties::<T>::try_mutate((collection_id, token_id), |properties| {341			properties.try_scoped_set(scope, property.key, property.value)342		})343		.map_err(<CommonError<T>>::from)?;344345		Ok(())346	}347348	pub fn set_scoped_token_properties(349		collection_id: CollectionId,350		token_id: TokenId,351		scope: PropertyScope,352		properties: impl Iterator<Item = Property>,353	) -> DispatchResult {354		TokenProperties::<T>::try_mutate((collection_id, token_id), |stored_properties| {355			stored_properties.try_scoped_set_from_iter(scope, properties)356		})357		.map_err(<CommonError<T>>::from)?;358359		Ok(())360	}361}362363// unchecked calls skips any permission checks364impl<T: Config> Pallet<T> {365	/// Create RFT collection366	///367	/// `init_collection` will take non-refundable deposit for collection creation.368	///369	/// - `data`: Contains settings for collection limits and permissions.370	pub fn init_collection(371		owner: T::CrossAccountId,372		payer: T::CrossAccountId,373		data: CreateCollectionData<T::AccountId>,374		flags: CollectionFlags,375	) -> Result<CollectionId, DispatchError> {376		<PalletCommon<T>>::init_collection(owner, payer, data, flags)377	}378379	/// Destroy RFT collection380	///381	/// `destroy_collection` will throw error if collection contains any tokens.382	/// Only owner can destroy collection.383	pub fn destroy_collection(384		collection: RefungibleHandle<T>,385		sender: &T::CrossAccountId,386	) -> DispatchResult {387		let id = collection.id;388389		if Self::collection_has_tokens(id) {390			return Err(<CommonError<T>>::CantDestroyNotEmptyCollection.into());391		}392393		// =========394395		PalletCommon::destroy_collection(collection.0, sender)?;396397		<TokensMinted<T>>::remove(id);398		<TokensBurnt<T>>::remove(id);399		let _ = <TotalSupply<T>>::clear_prefix((id,), u32::MAX, None);400		let _ = <Balance<T>>::clear_prefix((id,), u32::MAX, None);401		let _ = <Allowance<T>>::clear_prefix((id,), u32::MAX, None);402		let _ = <Owned<T>>::clear_prefix((id,), u32::MAX, None);403		let _ = <AccountBalance<T>>::clear_prefix((id,), u32::MAX, None);404		Ok(())405	}406407	fn collection_has_tokens(collection_id: CollectionId) -> bool {408		<TotalSupply<T>>::iter_prefix((collection_id,))409			.next()410			.is_some()411	}412413	pub fn burn_token_unchecked(414		collection: &RefungibleHandle<T>,415		owner: &T::CrossAccountId,416		token_id: TokenId,417	) -> DispatchResult {418		let burnt = <TokensBurnt<T>>::get(collection.id)419			.checked_add(1)420			.ok_or(ArithmeticError::Overflow)?;421422		<TokensBurnt<T>>::insert(collection.id, burnt);423		<TokenProperties<T>>::remove((collection.id, token_id));424		<TotalSupply<T>>::remove((collection.id, token_id));425		let _ = <Balance<T>>::clear_prefix((collection.id, token_id), u32::MAX, None);426		let _ = <Allowance<T>>::clear_prefix((collection.id, token_id), u32::MAX, None);427		<PalletEvm<T>>::deposit_log(428			ERC721Events::Transfer {429				from: *owner.as_eth(),430				to: H160::default(),431				token_id: token_id.into(),432			}433			.to_log(collection_id_to_address(collection.id)),434		);435		Ok(())436	}437438	/// Burn RFT token pieces439	///440	/// `burn` will decrease total amount of token pieces and amount owned by sender.441	/// `burn` can be called even if there are multiple owners of the RFT token.442	/// If sender wouldn't have any pieces left after `burn` than she will stop being443	/// one of the owners of the token. If there is no account that owns any pieces of444	/// the token than token will be burned too.445	///446	/// - `amount`: Amount of token pieces to burn.447	/// - `token`: Token who's pieces should be burned448	/// - `collection`: Collection that contains the token449	pub fn burn(450		collection: &RefungibleHandle<T>,451		owner: &T::CrossAccountId,452		token: TokenId,453		amount: u128,454	) -> DispatchResult {455		let total_supply = <TotalSupply<T>>::get((collection.id, token))456			.checked_sub(amount)457			.ok_or(<CommonError<T>>::TokenValueTooLow)?;458459		// This was probally last owner of this token?460		if total_supply == 0 {461			// Ensure user actually owns this amount462			ensure!(463				<Balance<T>>::get((collection.id, token, owner)) == amount,464				<CommonError<T>>::TokenValueTooLow465			);466			let account_balance = <AccountBalance<T>>::get((collection.id, owner))467				.checked_sub(1)468				// Should not occur469				.ok_or(ArithmeticError::Underflow)?;470471			// =========472473			<Owned<T>>::remove((collection.id, owner, token));474			<PalletStructure<T>>::unnest_if_nested(owner, collection.id, token);475			<AccountBalance<T>>::insert((collection.id, owner), account_balance);476			Self::burn_token_unchecked(collection, owner, token)?;477			<PalletEvm<T>>::deposit_log(478				ERC20Events::Transfer {479					from: *owner.as_eth(),480					to: H160::default(),481					value: amount.into(),482				}483				.to_log(collection_id_to_address(collection.id)),484			);485			<PalletCommon<T>>::deposit_event(CommonEvent::ItemDestroyed(486				collection.id,487				token,488				owner.clone(),489				amount,490			));491			return Ok(());492		}493494		let balance = <Balance<T>>::get((collection.id, token, owner))495			.checked_sub(amount)496			.ok_or(<CommonError<T>>::TokenValueTooLow)?;497		let account_balance = if balance == 0 {498			<AccountBalance<T>>::get((collection.id, owner))499				.checked_sub(1)500				// Should not occur501				.ok_or(ArithmeticError::Underflow)?502		} else {503			0504		};505506		// =========507508		if balance == 0 {509			<Owned<T>>::remove((collection.id, owner, token));510			<PalletStructure<T>>::unnest_if_nested(owner, collection.id, token);511			<Balance<T>>::remove((collection.id, token, owner));512			<AccountBalance<T>>::insert((collection.id, owner), account_balance);513514			if let Some(user) = Self::token_owner(collection.id, token) {515				<PalletEvm<T>>::deposit_log(516					ERC721Events::Transfer {517						from: erc::ADDRESS_FOR_PARTIALLY_OWNED_TOKENS,518						to: *user.as_eth(),519						token_id: token.into(),520					}521					.to_log(collection_id_to_address(collection.id)),522				);523			}524		} else {525			<Balance<T>>::insert((collection.id, token, owner), balance);526		}527		<TotalSupply<T>>::insert((collection.id, token), total_supply);528529		<PalletEvm<T>>::deposit_log(530			ERC20Events::Transfer {531				from: *owner.as_eth(),532				to: H160::default(),533				value: amount.into(),534			}535			.to_log(T::EvmTokenAddressMapping::token_to_address(536				collection.id,537				token,538			)),539		);540		<PalletCommon<T>>::deposit_event(CommonEvent::ItemDestroyed(541			collection.id,542			token,543			owner.clone(),544			amount,545		));546		Ok(())547	}548549	#[transactional]550	fn modify_token_properties(551		collection: &RefungibleHandle<T>,552		sender: &T::CrossAccountId,553		token_id: TokenId,554		properties: impl Iterator<Item = (PropertyKey, Option<PropertyValue>)>,555		is_token_create: bool,556		nesting_budget: &dyn Budget,557	) -> DispatchResult {558		let is_collection_admin = || collection.is_owner_or_admin(sender);559		let is_token_owner = || -> Result<bool, DispatchError> {560			let balance = collection.balance(sender.clone(), token_id);561			let total_pieces: u128 =562				Self::total_pieces(collection.id, token_id).unwrap_or(u128::MAX);563			if balance != total_pieces {564				return Ok(false);565			}566567			let is_bundle_owner = <PalletStructure<T>>::check_indirectly_owned(568				sender.clone(),569				collection.id,570				token_id,571				None,572				nesting_budget,573			)?;574575			Ok(is_bundle_owner)576		};577578		for (key, value) in properties {579			let permission = <PalletCommon<T>>::property_permissions(collection.id)580				.get(&key)581				.cloned()582				.unwrap_or_else(PropertyPermission::none);583584			let is_property_exists = TokenProperties::<T>::get((collection.id, token_id))585				.get(&key)586				.is_some();587588			match permission {589				PropertyPermission { mutable: false, .. } if is_property_exists => {590					return Err(<CommonError<T>>::NoPermission.into());591				}592593				PropertyPermission {594					collection_admin,595					token_owner,596					..597				} => {598					//TODO: investigate threats during public minting.599					let is_token_create =600						is_token_create && (collection_admin || token_owner) && value.is_some();601					if !(is_token_create602						|| (collection_admin && is_collection_admin())603						|| (token_owner && is_token_owner()?))604					{605						fail!(<CommonError<T>>::NoPermission);606					}607				}608			}609610			match value {611				Some(value) => {612					<TokenProperties<T>>::try_mutate((collection.id, token_id), |properties| {613						properties.try_set(key.clone(), value)614					})615					.map_err(<CommonError<T>>::from)?;616617					<PalletCommon<T>>::deposit_event(CommonEvent::TokenPropertySet(618						collection.id,619						token_id,620						key,621					));622				}623				None => {624					<TokenProperties<T>>::try_mutate((collection.id, token_id), |properties| {625						properties.remove(&key)626					})627					.map_err(<CommonError<T>>::from)?;628629					<PalletCommon<T>>::deposit_event(CommonEvent::TokenPropertyDeleted(630						collection.id,631						token_id,632						key,633					));634				}635			}636		}637638		Ok(())639	}640641	pub fn set_token_properties(642		collection: &RefungibleHandle<T>,643		sender: &T::CrossAccountId,644		token_id: TokenId,645		properties: impl Iterator<Item = Property>,646		is_token_create: bool,647		nesting_budget: &dyn Budget,648	) -> DispatchResult {649		Self::modify_token_properties(650			collection,651			sender,652			token_id,653			properties.map(|p| (p.key, Some(p.value))),654			is_token_create,655			nesting_budget,656		)657	}658659	pub fn set_token_property(660		collection: &RefungibleHandle<T>,661		sender: &T::CrossAccountId,662		token_id: TokenId,663		property: Property,664		nesting_budget: &dyn Budget,665	) -> DispatchResult {666		let is_token_create = false;667668		Self::set_token_properties(669			collection,670			sender,671			token_id,672			[property].into_iter(),673			is_token_create,674			nesting_budget,675		)676	}677678	pub fn delete_token_properties(679		collection: &RefungibleHandle<T>,680		sender: &T::CrossAccountId,681		token_id: TokenId,682		property_keys: impl Iterator<Item = PropertyKey>,683		nesting_budget: &dyn Budget,684	) -> DispatchResult {685		let is_token_create = false;686687		Self::modify_token_properties(688			collection,689			sender,690			token_id,691			property_keys.into_iter().map(|key| (key, None)),692			is_token_create,693			nesting_budget,694		)695	}696697	pub fn delete_token_property(698		collection: &RefungibleHandle<T>,699		sender: &T::CrossAccountId,700		token_id: TokenId,701		property_key: PropertyKey,702		nesting_budget: &dyn Budget,703	) -> DispatchResult {704		Self::delete_token_properties(705			collection,706			sender,707			token_id,708			[property_key].into_iter(),709			nesting_budget,710		)711	}712713	/// Transfer RFT token pieces from one account to another.714	///715	/// If the sender is no longer owns any pieces after the `transfer` than she stops being an owner of the token.716	///717	/// - `from`: Owner of token pieces to transfer.718	/// - `to`: Recepient of transfered token pieces.719	/// - `amount`: Amount of token pieces to transfer.720	/// - `token`: Token whos pieces should be transfered721	/// - `collection`: Collection that contains the token722	pub fn transfer(723		collection: &RefungibleHandle<T>,724		from: &T::CrossAccountId,725		to: &T::CrossAccountId,726		token: TokenId,727		amount: u128,728		nesting_budget: &dyn Budget,729	) -> DispatchResult {730		ensure!(731			collection.limits.transfers_enabled(),732			<CommonError<T>>::TransferNotAllowed733		);734735		if collection.permissions.access() == AccessMode::AllowList {736			collection.check_allowlist(from)?;737			collection.check_allowlist(to)?;738		}739		<PalletCommon<T>>::ensure_correct_receiver(to)?;740741		let initial_balance_from = <Balance<T>>::get((collection.id, token, from));742		let updated_balance_from = initial_balance_from743			.checked_sub(amount)744			.ok_or(<CommonError<T>>::TokenValueTooLow)?;745		let mut create_target = false;746		let from_to_differ = from != to;747		let updated_balance_to = if from != to {748			let old_balance = <Balance<T>>::get((collection.id, token, to));749			if old_balance == 0 {750				create_target = true;751			}752			Some(753				old_balance754					.checked_add(amount)755					.ok_or(ArithmeticError::Overflow)?,756			)757		} else {758			None759		};760761		let account_balance_from = if updated_balance_from == 0 {762			Some(763				<AccountBalance<T>>::get((collection.id, from))764					.checked_sub(1)765					// Should not occur766					.ok_or(ArithmeticError::Underflow)?,767			)768		} else {769			None770		};771		// Account data is created in token, AccountBalance should be increased772		// But only if from != to as we shouldn't check overflow in this case773		let account_balance_to = if create_target && from_to_differ {774			let account_balance_to = <AccountBalance<T>>::get((collection.id, to))775				.checked_add(1)776				.ok_or(ArithmeticError::Overflow)?;777			ensure!(778				account_balance_to < collection.limits.account_token_ownership_limit(),779				<CommonError<T>>::AccountTokenLimitExceeded,780			);781782			Some(account_balance_to)783		} else {784			None785		};786787		// =========788789		<PalletStructure<T>>::nest_if_sent_to_token(790			from.clone(),791			to,792			collection.id,793			token,794			nesting_budget,795		)?;796797		if let Some(updated_balance_to) = updated_balance_to {798			// from != to799			if updated_balance_from == 0 {800				<Balance<T>>::remove((collection.id, token, from));801				<PalletStructure<T>>::unnest_if_nested(from, collection.id, token);802			} else {803				<Balance<T>>::insert((collection.id, token, from), updated_balance_from);804			}805			<Balance<T>>::insert((collection.id, token, to), updated_balance_to);806			if let Some(account_balance_from) = account_balance_from {807				<AccountBalance<T>>::insert((collection.id, from), account_balance_from);808				<Owned<T>>::remove((collection.id, from, token));809			}810			if let Some(account_balance_to) = account_balance_to {811				<AccountBalance<T>>::insert((collection.id, to), account_balance_to);812				<Owned<T>>::insert((collection.id, to, token), true);813			}814		}815816		<PalletEvm<T>>::deposit_log(817			ERC20Events::Transfer {818				from: *from.as_eth(),819				to: *to.as_eth(),820				value: amount.into(),821			}822			.to_log(T::EvmTokenAddressMapping::token_to_address(823				collection.id,824				token,825			)),826		);827828		<PalletCommon<T>>::deposit_event(CommonEvent::Transfer(829			collection.id,830			token,831			from.clone(),832			to.clone(),833			amount,834		));835836		let total_supply = <TotalSupply<T>>::get((collection.id, token));837838		if amount == total_supply {839			// if token was fully owned by `from` and will be fully owned by `to` after transfer840			<PalletEvm<T>>::deposit_log(841				ERC721Events::Transfer {842					from: *from.as_eth(),843					to: *to.as_eth(),844					token_id: token.into(),845				}846				.to_log(collection_id_to_address(collection.id)),847			);848		} else if let Some(updated_balance_to) = updated_balance_to {849			// if `from` not equals `to`. This condition is needed to avoid sending event850			// when `from` fully owns token and sends part of token pieces to itself.851			if initial_balance_from == total_supply {852				// if token was fully owned by `from` and will be only partially owned by `to`853				// and `from` after transfer854				<PalletEvm<T>>::deposit_log(855					ERC721Events::Transfer {856						from: *from.as_eth(),857						to: erc::ADDRESS_FOR_PARTIALLY_OWNED_TOKENS,858						token_id: token.into(),859					}860					.to_log(collection_id_to_address(collection.id)),861				);862			} else if updated_balance_to == total_supply {863				// if token was partially owned by `from` and will be fully owned by `to` after transfer864				<PalletEvm<T>>::deposit_log(865					ERC721Events::Transfer {866						from: erc::ADDRESS_FOR_PARTIALLY_OWNED_TOKENS,867						to: *to.as_eth(),868						token_id: token.into(),869					}870					.to_log(collection_id_to_address(collection.id)),871				);872			}873		}874875		Ok(())876	}877878	/// Batched operation to create multiple RFT tokens.879	///880	/// Same as `create_item` but creates multiple tokens.881	///882	/// - `data`: Same as 'data` in `create_item` but contains data for multiple tokens.883	pub fn create_multiple_items(884		collection: &RefungibleHandle<T>,885		sender: &T::CrossAccountId,886		data: Vec<CreateItemData<T::CrossAccountId>>,887		nesting_budget: &dyn Budget,888	) -> DispatchResult {889		if !collection.is_owner_or_admin(sender) {890			ensure!(891				collection.permissions.mint_mode(),892				<CommonError<T>>::PublicMintingNotAllowed893			);894			collection.check_allowlist(sender)?;895896			for item in data.iter() {897				for user in item.users.keys() {898					collection.check_allowlist(user)?;899				}900			}901		}902903		for item in data.iter() {904			for (owner, _) in item.users.iter() {905				<PalletCommon<T>>::ensure_correct_receiver(owner)?;906			}907		}908909		// Total pieces per tokens910		let totals = data911			.iter()912			.map(|data| {913				Ok(data914					.users915					.iter()916					.map(|u| u.1)917					.try_fold(0u128, |acc, v| acc.checked_add(*v))918					.ok_or(ArithmeticError::Overflow)?)919			})920			.collect::<Result<Vec<_>, DispatchError>>()?;921		for total in &totals {922			ensure!(923				*total <= MAX_REFUNGIBLE_PIECES,924				<Error<T>>::WrongRefungiblePieces925			);926		}927928		let first_token_id = <TokensMinted<T>>::get(collection.id);929		let tokens_minted = first_token_id930			.checked_add(data.len() as u32)931			.ok_or(ArithmeticError::Overflow)?;932		ensure!(933			tokens_minted < collection.limits.token_limit(),934			<CommonError<T>>::CollectionTokenLimitExceeded935		);936937		let mut balances = BTreeMap::new();938		for data in &data {939			for owner in data.users.keys() {940				let balance = balances941					.entry(owner)942					.or_insert_with(|| <AccountBalance<T>>::get((collection.id, owner)));943				*balance = balance.checked_add(1).ok_or(ArithmeticError::Overflow)?;944945				ensure!(946					*balance <= collection.limits.account_token_ownership_limit(),947					<CommonError<T>>::AccountTokenLimitExceeded,948				);949			}950		}951952		for (i, token) in data.iter().enumerate() {953			let token_id = TokenId(first_token_id + i as u32 + 1);954			for (to, _) in token.users.iter() {955				<PalletStructure<T>>::check_nesting(956					sender.clone(),957					to,958					collection.id,959					token_id,960					nesting_budget,961				)?;962			}963		}964965		// =========966967		with_transaction(|| {968			for (i, data) in data.iter().enumerate() {969				let token_id = first_token_id + i as u32 + 1;970				<TotalSupply<T>>::insert((collection.id, token_id), totals[i]);971972				for (user, amount) in data.users.iter() {973					if *amount == 0 {974						continue;975					}976					<Balance<T>>::insert((collection.id, token_id, &user), amount);977					<Owned<T>>::insert((collection.id, &user, TokenId(token_id)), true);978					<PalletStructure<T>>::nest_if_sent_to_token_unchecked(979						user,980						collection.id,981						TokenId(token_id),982					);983				}984985				if let Err(e) = Self::set_token_properties(986					collection,987					sender,988					TokenId(token_id),989					data.properties.clone().into_iter(),990					true,991					nesting_budget,992				) {993					return TransactionOutcome::Rollback(Err(e));994				}995			}996			TransactionOutcome::Commit(Ok(()))997		})?;998999		<TokensMinted<T>>::insert(collection.id, tokens_minted);10001001		for (account, balance) in balances {1002			<AccountBalance<T>>::insert((collection.id, account), balance);1003		}10041005		for (i, token) in data.into_iter().enumerate() {1006			let token_id = first_token_id + i as u32 + 1;10071008			let receivers = token1009				.users1010				.into_iter()1011				.filter(|(_, amount)| *amount > 0)1012				.collect::<Vec<_>>();10131014			if let [(user, _)] = receivers.as_slice() {1015				// if there is exactly one receiver1016				<PalletEvm<T>>::deposit_log(1017					ERC721Events::Transfer {1018						from: H160::default(),1019						to: *user.as_eth(),1020						token_id: token_id.into(),1021					}1022					.to_log(collection_id_to_address(collection.id)),1023				);1024			} else if let [_, ..] = receivers.as_slice() {1025				// if there is more than one receiver1026				<PalletEvm<T>>::deposit_log(1027					ERC721Events::Transfer {1028						from: H160::default(),1029						to: erc::ADDRESS_FOR_PARTIALLY_OWNED_TOKENS,1030						token_id: token_id.into(),1031					}1032					.to_log(collection_id_to_address(collection.id)),1033				);1034			}10351036			for (user, amount) in receivers.into_iter() {1037				<PalletEvm<T>>::deposit_log(1038					ERC20Events::Transfer {1039						from: H160::default(),1040						to: *user.as_eth(),1041						value: amount.into(),1042					}1043					.to_log(T::EvmTokenAddressMapping::token_to_address(1044						collection.id,1045						TokenId(token_id),1046					)),1047				);1048				<PalletCommon<T>>::deposit_event(CommonEvent::ItemCreated(1049					collection.id,1050					TokenId(token_id),1051					user,1052					amount,1053				));1054			}1055		}1056		Ok(())1057	}10581059	pub fn set_allowance_unchecked(1060		collection: &RefungibleHandle<T>,1061		sender: &T::CrossAccountId,1062		spender: &T::CrossAccountId,1063		token: TokenId,1064		amount: u128,1065	) {1066		if amount == 0 {1067			<Allowance<T>>::remove((collection.id, token, sender, spender));1068		} else {1069			<Allowance<T>>::insert((collection.id, token, sender, spender), amount);1070		}10711072		<PalletEvm<T>>::deposit_log(1073			ERC20Events::Approval {1074				owner: *sender.as_eth(),1075				spender: *spender.as_eth(),1076				value: amount.into(),1077			}1078			.to_log(T::EvmTokenAddressMapping::token_to_address(1079				collection.id,1080				token,1081			)),1082		);1083		<PalletCommon<T>>::deposit_event(CommonEvent::Approved(1084			collection.id,1085			token,1086			sender.clone(),1087			spender.clone(),1088			amount,1089		))1090	}10911092	/// Set allowance for the spender to `transfer` or `burn` sender's token pieces.1093	///1094	/// - `amount`: Amount of token pieces the spender is allowed to `transfer` or `burn.1095	pub fn set_allowance(1096		collection: &RefungibleHandle<T>,1097		sender: &T::CrossAccountId,1098		spender: &T::CrossAccountId,1099		token: TokenId,1100		amount: u128,1101	) -> DispatchResult {1102		if collection.permissions.access() == AccessMode::AllowList {1103			collection.check_allowlist(sender)?;1104			collection.check_allowlist(spender)?;1105		}11061107		<PalletCommon<T>>::ensure_correct_receiver(spender)?;11081109		if <Balance<T>>::get((collection.id, token, sender)) < amount {1110			ensure!(1111				collection.ignores_owned_amount(sender) && Self::token_exists(collection, token),1112				<CommonError<T>>::CantApproveMoreThanOwned1113			);1114		}11151116		// =========11171118		Self::set_allowance_unchecked(collection, sender, spender, token, amount);1119		Ok(())1120	}11211122	/// Returns allowance, which should be set after transaction1123	fn check_allowed(1124		collection: &RefungibleHandle<T>,1125		spender: &T::CrossAccountId,1126		from: &T::CrossAccountId,1127		token: TokenId,1128		amount: u128,1129		nesting_budget: &dyn Budget,1130	) -> Result<Option<u128>, DispatchError> {1131		if spender.conv_eq(from) {1132			return Ok(None);1133		}1134		if collection.permissions.access() == AccessMode::AllowList {1135			// `from`, `to` checked in [`transfer`]1136			collection.check_allowlist(spender)?;1137		}1138		if let Some(source) = T::CrossTokenAddressMapping::address_to_token(from) {1139			// TODO: should collection owner be allowed to perform this transfer?1140			ensure!(1141				<PalletStructure<T>>::check_indirectly_owned(1142					spender.clone(),1143					source.0,1144					source.1,1145					None,1146					nesting_budget1147				)?,1148				<CommonError<T>>::ApprovedValueTooLow,1149			);1150			return Ok(None);1151		}1152		let allowance =1153			<Allowance<T>>::get((collection.id, token, from, &spender)).checked_sub(amount);1154		if allowance.is_none() {1155			ensure!(1156				collection.ignores_allowance(spender),1157				<CommonError<T>>::ApprovedValueTooLow1158			);1159		}1160		Ok(allowance)1161	}11621163	/// Transfer RFT token pieces from one account to another.1164	///1165	/// Same as the [`transfer`] but spender doesn't needs to be an owner of the token pieces.1166	/// The owner should set allowance for the spender to transfer pieces.1167	///1168	/// [`transfer`]: struct.Pallet.html#method.transfer1169	pub fn transfer_from(1170		collection: &RefungibleHandle<T>,1171		spender: &T::CrossAccountId,1172		from: &T::CrossAccountId,1173		to: &T::CrossAccountId,1174		token: TokenId,1175		amount: u128,1176		nesting_budget: &dyn Budget,1177	) -> DispatchResult {1178		let allowance =1179			Self::check_allowed(collection, spender, from, token, amount, nesting_budget)?;11801181		// =========11821183		Self::transfer(collection, from, to, token, amount, nesting_budget)?;1184		if let Some(allowance) = allowance {1185			Self::set_allowance_unchecked(collection, from, spender, token, allowance);1186		}1187		Ok(())1188	}11891190	/// Burn RFT token pieces from the account.1191	///1192	/// Same as the [`burn`] but spender doesn't need to be an owner of the token pieces. The owner should1193	/// set allowance for the spender to burn pieces1194	///1195	/// [`burn`]: struct.Pallet.html#method.burn1196	pub fn burn_from(1197		collection: &RefungibleHandle<T>,1198		spender: &T::CrossAccountId,1199		from: &T::CrossAccountId,1200		token: TokenId,1201		amount: u128,1202		nesting_budget: &dyn Budget,1203	) -> DispatchResult {1204		let allowance =1205			Self::check_allowed(collection, spender, from, token, amount, nesting_budget)?;12061207		// =========12081209		Self::burn(collection, from, token, amount)?;1210		if let Some(allowance) = allowance {1211			Self::set_allowance_unchecked(collection, from, spender, token, allowance);1212		}1213		Ok(())1214	}12151216	/// Create RFT token.1217	///1218	/// The sender should be the owner/admin of the collection or collection should be configured1219	/// to allow public minting.1220	///1221	/// - `data`: Contains list of users who will become the owners of the token pieces and amount1222	///   of token pieces they will receive.1223	pub fn create_item(1224		collection: &RefungibleHandle<T>,1225		sender: &T::CrossAccountId,1226		data: CreateItemData<T::CrossAccountId>,1227		nesting_budget: &dyn Budget,1228	) -> DispatchResult {1229		Self::create_multiple_items(collection, sender, vec![data], nesting_budget)1230	}12311232	/// Repartition RFT token.1233	///1234	/// `repartition` will set token balance of the sender and total amount of token pieces.1235	/// Sender should own all of the token pieces. `repartition' could be done even if some1236	/// token pieces were burned before.1237	///1238	/// - `amount`: Total amount of token pieces that the token will have after `repartition`.1239	pub fn repartition(1240		collection: &RefungibleHandle<T>,1241		owner: &T::CrossAccountId,1242		token: TokenId,1243		amount: u128,1244	) -> DispatchResult {1245		ensure!(1246			amount <= MAX_REFUNGIBLE_PIECES,1247			<Error<T>>::WrongRefungiblePieces1248		);1249		ensure!(amount > 0, <CommonError<T>>::TokenValueTooLow);1250		// Ensure user owns all pieces1251		let total_pieces = Self::total_pieces(collection.id, token).unwrap_or(u128::MAX);1252		let balance = <Balance<T>>::get((collection.id, token, owner));1253		ensure!(1254			total_pieces == balance,1255			<Error<T>>::RepartitionWhileNotOwningAllPieces1256		);12571258		<Balance<T>>::insert((collection.id, token, owner), amount);1259		<TotalSupply<T>>::insert((collection.id, token), amount);12601261		if amount > total_pieces {1262			let mint_amount = amount - total_pieces;1263			<PalletEvm<T>>::deposit_log(1264				ERC20Events::Transfer {1265					from: H160::default(),1266					to: *owner.as_eth(),1267					value: mint_amount.into(),1268				}1269				.to_log(T::EvmTokenAddressMapping::token_to_address(1270					collection.id,1271					token,1272				)),1273			);1274			<PalletCommon<T>>::deposit_event(CommonEvent::ItemCreated(1275				collection.id,1276				token,1277				owner.clone(),1278				mint_amount,1279			));1280		} else if total_pieces > amount {1281			let burn_amount = total_pieces - amount;1282			<PalletEvm<T>>::deposit_log(1283				ERC20Events::Transfer {1284					from: *owner.as_eth(),1285					to: H160::default(),1286					value: burn_amount.into(),1287				}1288				.to_log(T::EvmTokenAddressMapping::token_to_address(1289					collection.id,1290					token,1291				)),1292			);1293			<PalletCommon<T>>::deposit_event(CommonEvent::ItemDestroyed(1294				collection.id,1295				token,1296				owner.clone(),1297				burn_amount,1298			));1299		}13001301		Ok(())1302	}13031304	fn token_owner(collection_id: CollectionId, token_id: TokenId) -> Option<T::CrossAccountId> {1305		let mut owner = None;1306		let mut count = 0;1307		for key in Balance::<T>::iter_key_prefix((collection_id, token_id)) {1308			count += 1;1309			if count > 1 {1310				return None;1311			}1312			owner = Some(key);1313		}1314		owner1315	}13161317	fn total_pieces(collection_id: CollectionId, token_id: TokenId) -> Option<u128> {1318		<TotalSupply<T>>::try_get((collection_id, token_id)).ok()1319	}13201321	pub fn set_collection_properties(1322		collection: &RefungibleHandle<T>,1323		sender: &T::CrossAccountId,1324		properties: Vec<Property>,1325	) -> DispatchResult {1326		<PalletCommon<T>>::set_collection_properties(collection, sender, properties)1327	}13281329	pub fn delete_collection_properties(1330		collection: &RefungibleHandle<T>,1331		sender: &T::CrossAccountId,1332		property_keys: Vec<PropertyKey>,1333	) -> DispatchResult {1334		<PalletCommon<T>>::delete_collection_properties(collection, sender, property_keys)1335	}13361337	pub fn set_token_property_permissions(1338		collection: &RefungibleHandle<T>,1339		sender: &T::CrossAccountId,1340		property_permissions: Vec<PropertyKeyPermission>,1341	) -> DispatchResult {1342		<PalletCommon<T>>::set_token_property_permissions(collection, sender, property_permissions)1343	}13441345	pub fn set_scoped_token_property_permissions(1346		collection: &RefungibleHandle<T>,1347		sender: &T::CrossAccountId,1348		scope: PropertyScope,1349		property_permissions: Vec<PropertyKeyPermission>,1350	) -> DispatchResult {1351		<PalletCommon<T>>::set_scoped_token_property_permissions(1352			collection,1353			sender,1354			scope,1355			property_permissions,1356		)1357	}13581359	/// Returns 10 token in no particular order.1360	///1361	/// There is no direct way to get token holders in ascending order,1362	/// since `iter_prefix` returns values in no particular order.1363	/// Therefore, getting the 10 largest holders with a large value of holders1364	/// can lead to impact memory allocation + sorting with  `n * log (n)`.1365	pub fn token_owners(1366		collection_id: CollectionId,1367		token: TokenId,1368	) -> Option<Vec<T::CrossAccountId>> {1369		let res: Vec<T::CrossAccountId> = <Balance<T>>::iter_prefix((collection_id, token))1370			.map(|(owner, _amount)| owner)1371			.take(10)1372			.collect();13731374		if res.is_empty() {1375			None1376		} else {1377			Some(res)1378		}1379	}1380}