git.delta.rocks / unique-network / refs/commits / ec332a0b04f6

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)]131#[deprecated(since = "0.2.0", note = "ItemData is no more contains usefull data")]132pub struct ItemData {133	pub const_data: BoundedVec<u8, CustomDataLimit>,134135	#[version(..2)]136	pub variable_data: BoundedVec<u8, CustomDataLimit>,137}138139#[frame_support::pallet]140pub mod pallet {141	use super::*;142	use frame_support::{143		Blake2_128, Blake2_128Concat, Twox64Concat, pallet_prelude::*, storage::Key,144		traits::StorageVersion,145	};146	use frame_system::pallet_prelude::*;147	use up_data_structs::{CollectionId, TokenId};148	use super::weights::WeightInfo;149150	#[pallet::error]151	pub enum Error<T> {152		/// Not Refungible item data used to mint in Refungible collection.153		NotRefungibleDataUsedToMintFungibleCollectionToken,154		/// Maximum refungibility exceeded.155		WrongRefungiblePieces,156		/// Refungible token can't be repartitioned by user who isn't owns all pieces.157		RepartitionWhileNotOwningAllPieces,158		/// Refungible token can't nest other tokens.159		RefungibleDisallowsNesting,160		/// Setting item properties is not allowed.161		SettingPropertiesNotAllowed,162	}163164	#[pallet::config]165	pub trait Config:166		frame_system::Config + pallet_common::Config + pallet_structure::Config167	{168		type WeightInfo: WeightInfo;169	}170171	const STORAGE_VERSION: StorageVersion = StorageVersion::new(2);172173	#[pallet::pallet]174	#[pallet::storage_version(STORAGE_VERSION)]175	#[pallet::generate_store(pub(super) trait Store)]176	pub struct Pallet<T>(_);177178	/// Total amount of minted tokens in a collection.179	#[pallet::storage]180	pub type TokensMinted<T: Config> =181		StorageMap<Hasher = Twox64Concat, Key = CollectionId, Value = u32, QueryKind = ValueQuery>;182183	/// Amount of tokens burnt in a collection.184	#[pallet::storage]185	pub type TokensBurnt<T: Config> =186		StorageMap<Hasher = Twox64Concat, Key = CollectionId, Value = u32, QueryKind = ValueQuery>;187188	/// Token data, used to partially describe a token.189	// TODO: remove190	#[pallet::storage]191	#[deprecated(since = "0.2.0", note = "ItemData is no more contains usefull data")]192	pub type TokenData<T: Config> = StorageNMap<193		Key = (Key<Twox64Concat, CollectionId>, Key<Twox64Concat, TokenId>),194		Value = ItemData,195		QueryKind = ValueQuery,196	>;197198	/// Amount of pieces a refungible token is split into.199	#[pallet::storage]200	#[pallet::getter(fn token_properties)]201	pub type TokenProperties<T: Config> = StorageNMap<202		Key = (Key<Twox64Concat, CollectionId>, Key<Twox64Concat, TokenId>),203		Value = up_data_structs::Properties,204		QueryKind = ValueQuery,205		OnEmpty = up_data_structs::TokenProperties,206	>;207208	/// Total amount of pieces for token209	#[pallet::storage]210	pub type TotalSupply<T: Config> = StorageNMap<211		Key = (Key<Twox64Concat, CollectionId>, Key<Twox64Concat, TokenId>),212		Value = u128,213		QueryKind = ValueQuery,214	>;215216	/// Used to enumerate tokens owned by account.217	#[pallet::storage]218	pub type Owned<T: Config> = StorageNMap<219		Key = (220			Key<Twox64Concat, CollectionId>,221			Key<Blake2_128Concat, T::CrossAccountId>,222			Key<Twox64Concat, TokenId>,223		),224		Value = bool,225		QueryKind = ValueQuery,226	>;227228	/// Amount of tokens (not pieces) partially owned by an account within a collection.229	#[pallet::storage]230	pub type AccountBalance<T: Config> = StorageNMap<231		Key = (232			Key<Twox64Concat, CollectionId>,233			// Owner234			Key<Blake2_128Concat, T::CrossAccountId>,235		),236		Value = u32,237		QueryKind = ValueQuery,238	>;239240	/// Amount of token pieces owned by account.241	#[pallet::storage]242	pub type Balance<T: Config> = StorageNMap<243		Key = (244			Key<Twox64Concat, CollectionId>,245			Key<Twox64Concat, TokenId>,246			// Owner247			Key<Blake2_128Concat, T::CrossAccountId>,248		),249		Value = u128,250		QueryKind = ValueQuery,251	>;252253	/// Allowance set by a token owner for another user to perform one of certain transactions on a number of pieces of a token.254	#[pallet::storage]255	pub type Allowance<T: Config> = StorageNMap<256		Key = (257			Key<Twox64Concat, CollectionId>,258			Key<Twox64Concat, TokenId>,259			// Owner260			Key<Blake2_128, T::CrossAccountId>,261			// Spender262			Key<Blake2_128Concat, T::CrossAccountId>,263		),264		Value = u128,265		QueryKind = ValueQuery,266	>;267268	#[pallet::hooks]269	impl<T: Config> Hooks<BlockNumberFor<T>> for Pallet<T> {270		fn on_runtime_upgrade() -> Weight {271			let storage_version = StorageVersion::get::<Pallet<T>>();272			if storage_version < StorageVersion::new(2) {273				<TokenData<T>>::remove_all(None);274			}275			StorageVersion::new(2).put::<Pallet<T>>();276277			0278		}279	}280}281282pub struct RefungibleHandle<T: Config>(pallet_common::CollectionHandle<T>);283impl<T: Config> RefungibleHandle<T> {284	pub fn cast(inner: pallet_common::CollectionHandle<T>) -> Self {285		Self(inner)286	}287	pub fn into_inner(self) -> pallet_common::CollectionHandle<T> {288		self.0289	}290	pub fn common_mut(&mut self) -> &mut pallet_common::CollectionHandle<T> {291		&mut self.0292	}293}294295impl<T: Config> Deref for RefungibleHandle<T> {296	type Target = pallet_common::CollectionHandle<T>;297298	fn deref(&self) -> &Self::Target {299		&self.0300	}301}302303impl<T: Config> WithRecorder<T> for RefungibleHandle<T> {304	fn recorder(&self) -> &pallet_evm_coder_substrate::SubstrateRecorder<T> {305		self.0.recorder()306	}307	fn into_recorder(self) -> pallet_evm_coder_substrate::SubstrateRecorder<T> {308		self.0.into_recorder()309	}310}311312impl<T: Config> Pallet<T> {313	/// Get number of RFT tokens in collection314	pub fn total_supply(collection: &RefungibleHandle<T>) -> u32 {315		<TokensMinted<T>>::get(collection.id) - <TokensBurnt<T>>::get(collection.id)316	}317318	/// Check that RFT token exists319	///320	/// - `token`: Token ID.321	pub fn token_exists(collection: &RefungibleHandle<T>, token: TokenId) -> bool {322		<TotalSupply<T>>::contains_key((collection.id, token))323	}324325	pub fn set_scoped_token_property(326		collection_id: CollectionId,327		token_id: TokenId,328		scope: PropertyScope,329		property: Property,330	) -> DispatchResult {331		TokenProperties::<T>::try_mutate((collection_id, token_id), |properties| {332			properties.try_scoped_set(scope, property.key, property.value)333		})334		.map_err(<CommonError<T>>::from)?;335336		Ok(())337	}338339	pub fn set_scoped_token_properties(340		collection_id: CollectionId,341		token_id: TokenId,342		scope: PropertyScope,343		properties: impl Iterator<Item = Property>,344	) -> DispatchResult {345		TokenProperties::<T>::try_mutate((collection_id, token_id), |stored_properties| {346			stored_properties.try_scoped_set_from_iter(scope, properties)347		})348		.map_err(<CommonError<T>>::from)?;349350		Ok(())351	}352}353354// unchecked calls skips any permission checks355impl<T: Config> Pallet<T> {356	/// Create RFT collection357	///358	/// `init_collection` will take non-refundable deposit for collection creation.359	///360	/// - `data`: Contains settings for collection limits and permissions.361	pub fn init_collection(362		owner: T::CrossAccountId,363		data: CreateCollectionData<T::AccountId>,364	) -> Result<CollectionId, DispatchError> {365		<PalletCommon<T>>::init_collection(owner, data, false)366	}367368	/// Destroy RFT collection369	///370	/// `destroy_collection` will throw error if collection contains any tokens.371	/// Only owner can destroy collection.372	pub fn destroy_collection(373		collection: RefungibleHandle<T>,374		sender: &T::CrossAccountId,375	) -> DispatchResult {376		let id = collection.id;377378		if Self::collection_has_tokens(id) {379			return Err(<CommonError<T>>::CantDestroyNotEmptyCollection.into());380		}381382		// =========383384		PalletCommon::destroy_collection(collection.0, sender)?;385386		<TokensMinted<T>>::remove(id);387		<TokensBurnt<T>>::remove(id);388		<TotalSupply<T>>::remove_prefix((id,), None);389		<Balance<T>>::remove_prefix((id,), None);390		<Allowance<T>>::remove_prefix((id,), None);391		<Owned<T>>::remove_prefix((id,), None);392		<AccountBalance<T>>::remove_prefix((id,), None);393		Ok(())394	}395396	fn collection_has_tokens(collection_id: CollectionId) -> bool {397		<TotalSupply<T>>::iter_prefix((collection_id,))398			.next()399			.is_some()400	}401402	pub fn burn_token_unchecked(403		collection: &RefungibleHandle<T>,404		owner: &T::CrossAccountId,405		token_id: TokenId,406	) -> DispatchResult {407		let burnt = <TokensBurnt<T>>::get(collection.id)408			.checked_add(1)409			.ok_or(ArithmeticError::Overflow)?;410411		<TokensBurnt<T>>::insert(collection.id, burnt);412		<TokenProperties<T>>::remove((collection.id, token_id));413		<TotalSupply<T>>::remove((collection.id, token_id));414		<Balance<T>>::remove_prefix((collection.id, token_id), None);415		<Allowance<T>>::remove_prefix((collection.id, token_id), None);416417		<PalletEvm<T>>::deposit_log(418			ERC721Events::Transfer {419				from: *owner.as_eth(),420				to: H160::default(),421				token_id: token_id.into(),422			}423			.to_log(collection_id_to_address(collection.id)),424		);425		Ok(())426	}427428	/// Burn RFT token pieces429	///430	/// `burn` will decrease total amount of token pieces and amount owned by sender.431	/// `burn` can be called even if there are multiple owners of the RFT token.432	/// If sender wouldn't have any pieces left after `burn` than she will stop being433	/// one of the owners of the token. If there is no account that owns any pieces of434	/// the token than token will be burned too.435	///436	/// - `amount`: Amount of token pieces to burn.437	/// - `token`: Token who's pieces should be burned438	/// - `collection`: Collection that contains the token439	pub fn burn(440		collection: &RefungibleHandle<T>,441		owner: &T::CrossAccountId,442		token: TokenId,443		amount: u128,444	) -> DispatchResult {445		let total_supply = <TotalSupply<T>>::get((collection.id, token))446			.checked_sub(amount)447			.ok_or(<CommonError<T>>::TokenValueTooLow)?;448449		// This was probally last owner of this token?450		if total_supply == 0 {451			// Ensure user actually owns this amount452			ensure!(453				<Balance<T>>::get((collection.id, token, owner)) == amount,454				<CommonError<T>>::TokenValueTooLow455			);456			let account_balance = <AccountBalance<T>>::get((collection.id, owner))457				.checked_sub(1)458				// Should not occur459				.ok_or(ArithmeticError::Underflow)?;460461			// =========462463			<Owned<T>>::remove((collection.id, owner, token));464			<PalletStructure<T>>::unnest_if_nested(owner, collection.id, token);465			<AccountBalance<T>>::insert((collection.id, owner), account_balance);466			Self::burn_token_unchecked(collection, owner, token)?;467			<PalletEvm<T>>::deposit_log(468				ERC20Events::Transfer {469					from: *owner.as_eth(),470					to: H160::default(),471					value: amount.into(),472				}473				.to_log(collection_id_to_address(collection.id)),474			);475			<PalletCommon<T>>::deposit_event(CommonEvent::ItemDestroyed(476				collection.id,477				token,478				owner.clone(),479				amount,480			));481			return Ok(());482		}483484		let balance = <Balance<T>>::get((collection.id, token, owner))485			.checked_sub(amount)486			.ok_or(<CommonError<T>>::TokenValueTooLow)?;487		let account_balance = if balance == 0 {488			<AccountBalance<T>>::get((collection.id, owner))489				.checked_sub(1)490				// Should not occur491				.ok_or(ArithmeticError::Underflow)?492		} else {493			0494		};495496		// =========497498		if balance == 0 {499			<Owned<T>>::remove((collection.id, owner, token));500			<PalletStructure<T>>::unnest_if_nested(owner, collection.id, token);501			<Balance<T>>::remove((collection.id, token, owner));502			<AccountBalance<T>>::insert((collection.id, owner), account_balance);503504			if let Some(user) = Self::token_owner(collection.id, token) {505				<PalletEvm<T>>::deposit_log(506					ERC721Events::Transfer {507						from: erc::ADDRESS_FOR_PARTIALLY_OWNED_TOKENS,508						to: *user.as_eth(),509						token_id: token.into(),510					}511					.to_log(collection_id_to_address(collection.id)),512				);513			}514		} else {515			<Balance<T>>::insert((collection.id, token, owner), balance);516		}517		<TotalSupply<T>>::insert((collection.id, token), total_supply);518519		<PalletEvm<T>>::deposit_log(520			ERC20Events::Transfer {521				from: *owner.as_eth(),522				to: H160::default(),523				value: amount.into(),524			}525			.to_log(T::EvmTokenAddressMapping::token_to_address(526				collection.id,527				token,528			)),529		);530		<PalletCommon<T>>::deposit_event(CommonEvent::ItemDestroyed(531			collection.id,532			token,533			owner.clone(),534			amount,535		));536		Ok(())537	}538539	#[transactional]540	fn modify_token_properties(541		collection: &RefungibleHandle<T>,542		sender: &T::CrossAccountId,543		token_id: TokenId,544		properties: impl Iterator<Item = (PropertyKey, Option<PropertyValue>)>,545		is_token_create: bool,546		nesting_budget: &dyn Budget,547	) -> DispatchResult {548		let is_collection_admin = || collection.is_owner_or_admin(sender);549		let is_token_owner = || -> Result<bool, DispatchError> {550			let balance = collection.balance(sender.clone(), token_id);551			let total_pieces: u128 =552				Self::total_pieces(collection.id, token_id).unwrap_or(u128::MAX);553			if balance != total_pieces {554				return Ok(false);555			}556557			let is_bundle_owner = <PalletStructure<T>>::check_indirectly_owned(558				sender.clone(),559				collection.id,560				token_id,561				None,562				nesting_budget,563			)?;564565			Ok(is_bundle_owner)566		};567568		for (key, value) in properties {569			let permission = <PalletCommon<T>>::property_permissions(collection.id)570				.get(&key)571				.cloned()572				.unwrap_or_else(PropertyPermission::none);573574			let is_property_exists = TokenProperties::<T>::get((collection.id, token_id))575				.get(&key)576				.is_some();577578			match permission {579				PropertyPermission { mutable: false, .. } if is_property_exists => {580					return Err(<CommonError<T>>::NoPermission.into());581				}582583				PropertyPermission {584					collection_admin,585					token_owner,586					..587				} => {588					//TODO: investigate threats during public minting.589					let is_token_create =590						is_token_create && (collection_admin || token_owner) && value.is_some();591					if !(is_token_create592						|| (collection_admin && is_collection_admin())593						|| (token_owner && is_token_owner()?))594					{595						fail!(<CommonError<T>>::NoPermission);596					}597				}598			}599600			match value {601				Some(value) => {602					<TokenProperties<T>>::try_mutate((collection.id, token_id), |properties| {603						properties.try_set(key.clone(), value)604					})605					.map_err(<CommonError<T>>::from)?;606607					<PalletCommon<T>>::deposit_event(CommonEvent::TokenPropertySet(608						collection.id,609						token_id,610						key,611					));612				}613				None => {614					<TokenProperties<T>>::try_mutate((collection.id, token_id), |properties| {615						properties.remove(&key)616					})617					.map_err(<CommonError<T>>::from)?;618619					<PalletCommon<T>>::deposit_event(CommonEvent::TokenPropertyDeleted(620						collection.id,621						token_id,622						key,623					));624				}625			}626		}627628		Ok(())629	}630631	pub fn set_token_properties(632		collection: &RefungibleHandle<T>,633		sender: &T::CrossAccountId,634		token_id: TokenId,635		properties: impl Iterator<Item = Property>,636		is_token_create: bool,637		nesting_budget: &dyn Budget,638	) -> DispatchResult {639		Self::modify_token_properties(640			collection,641			sender,642			token_id,643			properties.map(|p| (p.key, Some(p.value))),644			is_token_create,645			nesting_budget,646		)647	}648649	pub fn set_token_property(650		collection: &RefungibleHandle<T>,651		sender: &T::CrossAccountId,652		token_id: TokenId,653		property: Property,654		nesting_budget: &dyn Budget,655	) -> DispatchResult {656		let is_token_create = false;657658		Self::set_token_properties(659			collection,660			sender,661			token_id,662			[property].into_iter(),663			is_token_create,664			nesting_budget,665		)666	}667668	pub fn delete_token_properties(669		collection: &RefungibleHandle<T>,670		sender: &T::CrossAccountId,671		token_id: TokenId,672		property_keys: impl Iterator<Item = PropertyKey>,673		nesting_budget: &dyn Budget,674	) -> DispatchResult {675		let is_token_create = false;676677		Self::modify_token_properties(678			collection,679			sender,680			token_id,681			property_keys.into_iter().map(|key| (key, None)),682			is_token_create,683			nesting_budget,684		)685	}686687	pub fn delete_token_property(688		collection: &RefungibleHandle<T>,689		sender: &T::CrossAccountId,690		token_id: TokenId,691		property_key: PropertyKey,692		nesting_budget: &dyn Budget,693	) -> DispatchResult {694		Self::delete_token_properties(695			collection,696			sender,697			token_id,698			[property_key].into_iter(),699			nesting_budget,700		)701	}702703	/// Transfer RFT token pieces from one account to another.704	///705	/// If the sender is no longer owns any pieces after the `transfer` than she stops being an owner of the token.706	///707	/// - `from`: Owner of token pieces to transfer.708	/// - `to`: Recepient of transfered token pieces.709	/// - `amount`: Amount of token pieces to transfer.710	/// - `token`: Token whos pieces should be transfered711	/// - `collection`: Collection that contains the token712	pub fn transfer(713		collection: &RefungibleHandle<T>,714		from: &T::CrossAccountId,715		to: &T::CrossAccountId,716		token: TokenId,717		amount: u128,718		nesting_budget: &dyn Budget,719	) -> DispatchResult {720		ensure!(721			collection.limits.transfers_enabled(),722			<CommonError<T>>::TransferNotAllowed723		);724725		if collection.permissions.access() == AccessMode::AllowList {726			collection.check_allowlist(from)?;727			collection.check_allowlist(to)?;728		}729		<PalletCommon<T>>::ensure_correct_receiver(to)?;730731		let initial_balance_from = <Balance<T>>::get((collection.id, token, from));732		let updated_balance_from = initial_balance_from733			.checked_sub(amount)734			.ok_or(<CommonError<T>>::TokenValueTooLow)?;735		let mut create_target = false;736		let from_to_differ = from != to;737		let updated_balance_to = if from != to {738			let old_balance = <Balance<T>>::get((collection.id, token, to));739			if old_balance == 0 {740				create_target = true;741			}742			Some(743				old_balance744					.checked_add(amount)745					.ok_or(ArithmeticError::Overflow)?,746			)747		} else {748			None749		};750751		let account_balance_from = if updated_balance_from == 0 {752			Some(753				<AccountBalance<T>>::get((collection.id, from))754					.checked_sub(1)755					// Should not occur756					.ok_or(ArithmeticError::Underflow)?,757			)758		} else {759			None760		};761		// Account data is created in token, AccountBalance should be increased762		// But only if from != to as we shouldn't check overflow in this case763		let account_balance_to = if create_target && from_to_differ {764			let account_balance_to = <AccountBalance<T>>::get((collection.id, to))765				.checked_add(1)766				.ok_or(ArithmeticError::Overflow)?;767			ensure!(768				account_balance_to < collection.limits.account_token_ownership_limit(),769				<CommonError<T>>::AccountTokenLimitExceeded,770			);771772			Some(account_balance_to)773		} else {774			None775		};776777		// =========778779		<PalletStructure<T>>::nest_if_sent_to_token(780			from.clone(),781			to,782			collection.id,783			token,784			nesting_budget,785		)?;786787		if let Some(updated_balance_to) = updated_balance_to {788			// from != to789			if updated_balance_from == 0 {790				<Balance<T>>::remove((collection.id, token, from));791				<PalletStructure<T>>::unnest_if_nested(from, collection.id, token);792			} else {793				<Balance<T>>::insert((collection.id, token, from), updated_balance_from);794			}795			<Balance<T>>::insert((collection.id, token, to), updated_balance_to);796			if let Some(account_balance_from) = account_balance_from {797				<AccountBalance<T>>::insert((collection.id, from), account_balance_from);798				<Owned<T>>::remove((collection.id, from, token));799			}800			if let Some(account_balance_to) = account_balance_to {801				<AccountBalance<T>>::insert((collection.id, to), account_balance_to);802				<Owned<T>>::insert((collection.id, to, token), true);803			}804		}805806		<PalletEvm<T>>::deposit_log(807			ERC20Events::Transfer {808				from: *from.as_eth(),809				to: *to.as_eth(),810				value: amount.into(),811			}812			.to_log(T::EvmTokenAddressMapping::token_to_address(813				collection.id,814				token,815			)),816		);817818		<PalletCommon<T>>::deposit_event(CommonEvent::Transfer(819			collection.id,820			token,821			from.clone(),822			to.clone(),823			amount,824		));825826		let total_supply = <TotalSupply<T>>::get((collection.id, token));827828		if amount == total_supply {829			// if token was fully owned by `from` and will be fully owned by `to` after transfer830			<PalletEvm<T>>::deposit_log(831				ERC721Events::Transfer {832					from: *from.as_eth(),833					to: *to.as_eth(),834					token_id: token.into(),835				}836				.to_log(collection_id_to_address(collection.id)),837			);838		} else if let Some(updated_balance_to) = updated_balance_to {839			// if `from` not equals `to`. This condition is needed to avoid sending event840			// when `from` fully owns token and sends part of token pieces to itself.841			if initial_balance_from == total_supply {842				// if token was fully owned by `from` and will be only partially owned by `to`843				// and `from` after transfer844				<PalletEvm<T>>::deposit_log(845					ERC721Events::Transfer {846						from: *from.as_eth(),847						to: erc::ADDRESS_FOR_PARTIALLY_OWNED_TOKENS,848						token_id: token.into(),849					}850					.to_log(collection_id_to_address(collection.id)),851				);852			} else if updated_balance_to == total_supply {853				// if token was partially owned by `from` and will be fully owned by `to` after transfer854				<PalletEvm<T>>::deposit_log(855					ERC721Events::Transfer {856						from: erc::ADDRESS_FOR_PARTIALLY_OWNED_TOKENS,857						to: *to.as_eth(),858						token_id: token.into(),859					}860					.to_log(collection_id_to_address(collection.id)),861				);862			}863		}864865		Ok(())866	}867868	/// Batched operation to create multiple RFT tokens.869	///870	/// Same as `create_item` but creates multiple tokens.871	///872	/// - `data`: Same as 'data` in `create_item` but contains data for multiple tokens.873	pub fn create_multiple_items(874		collection: &RefungibleHandle<T>,875		sender: &T::CrossAccountId,876		data: Vec<CreateItemData<T>>,877		nesting_budget: &dyn Budget,878	) -> DispatchResult {879		if !collection.is_owner_or_admin(sender) {880			ensure!(881				collection.permissions.mint_mode(),882				<CommonError<T>>::PublicMintingNotAllowed883			);884			collection.check_allowlist(sender)?;885886			for item in data.iter() {887				for user in item.users.keys() {888					collection.check_allowlist(user)?;889				}890			}891		}892893		for item in data.iter() {894			for (owner, _) in item.users.iter() {895				<PalletCommon<T>>::ensure_correct_receiver(owner)?;896			}897		}898899		// Total pieces per tokens900		let totals = data901			.iter()902			.map(|data| {903				Ok(data904					.users905					.iter()906					.map(|u| u.1)907					.try_fold(0u128, |acc, v| acc.checked_add(*v))908					.ok_or(ArithmeticError::Overflow)?)909			})910			.collect::<Result<Vec<_>, DispatchError>>()?;911		for total in &totals {912			ensure!(913				*total <= MAX_REFUNGIBLE_PIECES,914				<Error<T>>::WrongRefungiblePieces915			);916		}917918		let first_token_id = <TokensMinted<T>>::get(collection.id);919		let tokens_minted = first_token_id920			.checked_add(data.len() as u32)921			.ok_or(ArithmeticError::Overflow)?;922		ensure!(923			tokens_minted < collection.limits.token_limit(),924			<CommonError<T>>::CollectionTokenLimitExceeded925		);926927		let mut balances = BTreeMap::new();928		for data in &data {929			for owner in data.users.keys() {930				let balance = balances931					.entry(owner)932					.or_insert_with(|| <AccountBalance<T>>::get((collection.id, owner)));933				*balance = balance.checked_add(1).ok_or(ArithmeticError::Overflow)?;934935				ensure!(936					*balance <= collection.limits.account_token_ownership_limit(),937					<CommonError<T>>::AccountTokenLimitExceeded,938				);939			}940		}941942		for (i, token) in data.iter().enumerate() {943			let token_id = TokenId(first_token_id + i as u32 + 1);944			for (to, _) in token.users.iter() {945				<PalletStructure<T>>::check_nesting(946					sender.clone(),947					to,948					collection.id,949					token_id,950					nesting_budget,951				)?;952			}953		}954955		// =========956957		with_transaction(|| {958			for (i, data) in data.iter().enumerate() {959				let token_id = first_token_id + i as u32 + 1;960				<TotalSupply<T>>::insert((collection.id, token_id), totals[i]);961962				for (user, amount) in data.users.iter() {963					if *amount == 0 {964						continue;965					}966					<Balance<T>>::insert((collection.id, token_id, &user), amount);967					<Owned<T>>::insert((collection.id, &user, TokenId(token_id)), true);968					<PalletStructure<T>>::nest_if_sent_to_token_unchecked(969						user,970						collection.id,971						TokenId(token_id),972					);973				}974975				if let Err(e) = Self::set_token_properties(976					collection,977					sender,978					TokenId(token_id),979					data.properties.clone().into_iter(),980					true,981					nesting_budget,982				) {983					return TransactionOutcome::Rollback(Err(e));984				}985			}986			TransactionOutcome::Commit(Ok(()))987		})?;988989		<TokensMinted<T>>::insert(collection.id, tokens_minted);990991		for (account, balance) in balances {992			<AccountBalance<T>>::insert((collection.id, account), balance);993		}994995		for (i, token) in data.into_iter().enumerate() {996			let token_id = first_token_id + i as u32 + 1;997998			let receivers = token999				.users1000				.into_iter()1001				.filter(|(_, amount)| *amount > 0)1002				.collect::<Vec<_>>();10031004			if let [(user, _)] = receivers.as_slice() {1005				// if there is exactly one receiver1006				<PalletEvm<T>>::deposit_log(1007					ERC721Events::Transfer {1008						from: H160::default(),1009						to: *user.as_eth(),1010						token_id: token_id.into(),1011					}1012					.to_log(collection_id_to_address(collection.id)),1013				);1014			} else if let [_, ..] = receivers.as_slice() {1015				// if there is more than one receiver1016				<PalletEvm<T>>::deposit_log(1017					ERC721Events::Transfer {1018						from: H160::default(),1019						to: erc::ADDRESS_FOR_PARTIALLY_OWNED_TOKENS,1020						token_id: token_id.into(),1021					}1022					.to_log(collection_id_to_address(collection.id)),1023				);1024			}10251026			for (user, amount) in receivers.into_iter() {1027				<PalletEvm<T>>::deposit_log(1028					ERC20Events::Transfer {1029						from: H160::default(),1030						to: *user.as_eth(),1031						value: amount.into(),1032					}1033					.to_log(T::EvmTokenAddressMapping::token_to_address(1034						collection.id,1035						TokenId(token_id),1036					)),1037				);1038				<PalletCommon<T>>::deposit_event(CommonEvent::ItemCreated(1039					collection.id,1040					TokenId(token_id),1041					user,1042					amount,1043				));1044			}1045		}1046		Ok(())1047	}10481049	pub fn set_allowance_unchecked(1050		collection: &RefungibleHandle<T>,1051		sender: &T::CrossAccountId,1052		spender: &T::CrossAccountId,1053		token: TokenId,1054		amount: u128,1055	) {1056		if amount == 0 {1057			<Allowance<T>>::remove((collection.id, token, sender, spender));1058		} else {1059			<Allowance<T>>::insert((collection.id, token, sender, spender), amount);1060		}10611062		<PalletEvm<T>>::deposit_log(1063			ERC20Events::Approval {1064				owner: *sender.as_eth(),1065				spender: *spender.as_eth(),1066				value: amount.into(),1067			}1068			.to_log(T::EvmTokenAddressMapping::token_to_address(1069				collection.id,1070				token,1071			)),1072		);1073		<PalletCommon<T>>::deposit_event(CommonEvent::Approved(1074			collection.id,1075			token,1076			sender.clone(),1077			spender.clone(),1078			amount,1079		))1080	}10811082	/// Set allowance for the spender to `transfer` or `burn` sender's token pieces.1083	///1084	/// - `amount`: Amount of token pieces the spender is allowed to `transfer` or `burn.1085	pub fn set_allowance(1086		collection: &RefungibleHandle<T>,1087		sender: &T::CrossAccountId,1088		spender: &T::CrossAccountId,1089		token: TokenId,1090		amount: u128,1091	) -> DispatchResult {1092		if collection.permissions.access() == AccessMode::AllowList {1093			collection.check_allowlist(sender)?;1094			collection.check_allowlist(spender)?;1095		}10961097		<PalletCommon<T>>::ensure_correct_receiver(spender)?;10981099		if <Balance<T>>::get((collection.id, token, sender)) < amount {1100			ensure!(1101				collection.ignores_owned_amount(sender) && Self::token_exists(collection, token),1102				<CommonError<T>>::CantApproveMoreThanOwned1103			);1104		}11051106		// =========11071108		Self::set_allowance_unchecked(collection, sender, spender, token, amount);1109		Ok(())1110	}11111112	/// Returns allowance, which should be set after transaction1113	fn check_allowed(1114		collection: &RefungibleHandle<T>,1115		spender: &T::CrossAccountId,1116		from: &T::CrossAccountId,1117		token: TokenId,1118		amount: u128,1119		nesting_budget: &dyn Budget,1120	) -> Result<Option<u128>, DispatchError> {1121		if spender.conv_eq(from) {1122			return Ok(None);1123		}1124		if collection.permissions.access() == AccessMode::AllowList {1125			// `from`, `to` checked in [`transfer`]1126			collection.check_allowlist(spender)?;1127		}1128		if let Some(source) = T::CrossTokenAddressMapping::address_to_token(from) {1129			// TODO: should collection owner be allowed to perform this transfer?1130			ensure!(1131				<PalletStructure<T>>::check_indirectly_owned(1132					spender.clone(),1133					source.0,1134					source.1,1135					None,1136					nesting_budget1137				)?,1138				<CommonError<T>>::ApprovedValueTooLow,1139			);1140			return Ok(None);1141		}1142		let allowance =1143			<Allowance<T>>::get((collection.id, token, from, &spender)).checked_sub(amount);1144		if allowance.is_none() {1145			ensure!(1146				collection.ignores_allowance(spender),1147				<CommonError<T>>::ApprovedValueTooLow1148			);1149		}1150		Ok(allowance)1151	}11521153	/// Transfer RFT token pieces from one account to another.1154	///1155	/// Same as the [`transfer`] but spender doesn't needs to be an owner of the token pieces.1156	/// The owner should set allowance for the spender to transfer pieces.1157	///1158	/// [`transfer`]: struct.Pallet.html#method.transfer1159	pub fn transfer_from(1160		collection: &RefungibleHandle<T>,1161		spender: &T::CrossAccountId,1162		from: &T::CrossAccountId,1163		to: &T::CrossAccountId,1164		token: TokenId,1165		amount: u128,1166		nesting_budget: &dyn Budget,1167	) -> DispatchResult {1168		let allowance =1169			Self::check_allowed(collection, spender, from, token, amount, nesting_budget)?;11701171		// =========11721173		Self::transfer(collection, from, to, token, amount, nesting_budget)?;1174		if let Some(allowance) = allowance {1175			Self::set_allowance_unchecked(collection, from, spender, token, allowance);1176		}1177		Ok(())1178	}11791180	/// Burn RFT token pieces from the account.1181	///1182	/// Same as the [`burn`] but spender doesn't need to be an owner of the token pieces. The owner should1183	/// set allowance for the spender to burn pieces1184	///1185	/// [`burn`]: struct.Pallet.html#method.burn1186	pub fn burn_from(1187		collection: &RefungibleHandle<T>,1188		spender: &T::CrossAccountId,1189		from: &T::CrossAccountId,1190		token: TokenId,1191		amount: u128,1192		nesting_budget: &dyn Budget,1193	) -> DispatchResult {1194		let allowance =1195			Self::check_allowed(collection, spender, from, token, amount, nesting_budget)?;11961197		// =========11981199		Self::burn(collection, from, token, amount)?;1200		if let Some(allowance) = allowance {1201			Self::set_allowance_unchecked(collection, from, spender, token, allowance);1202		}1203		Ok(())1204	}12051206	/// Create RFT token.1207	///1208	/// The sender should be the owner/admin of the collection or collection should be configured1209	/// to allow public minting.1210	///1211	/// - `data`: Contains list of users who will become the owners of the token pieces and amount1212	///   of token pieces they will receive.1213	pub fn create_item(1214		collection: &RefungibleHandle<T>,1215		sender: &T::CrossAccountId,1216		data: CreateItemData<T>,1217		nesting_budget: &dyn Budget,1218	) -> DispatchResult {1219		Self::create_multiple_items(collection, sender, vec![data], nesting_budget)1220	}12211222	/// Repartition RFT token.1223	///1224	/// `repartition` will set token balance of the sender and total amount of token pieces.1225	/// Sender should own all of the token pieces. `repartition' could be done even if some1226	/// token pieces were burned before.1227	///1228	/// - `amount`: Total amount of token pieces that the token will have after `repartition`.1229	pub fn repartition(1230		collection: &RefungibleHandle<T>,1231		owner: &T::CrossAccountId,1232		token: TokenId,1233		amount: u128,1234	) -> DispatchResult {1235		ensure!(1236			amount <= MAX_REFUNGIBLE_PIECES,1237			<Error<T>>::WrongRefungiblePieces1238		);1239		ensure!(amount > 0, <CommonError<T>>::TokenValueTooLow);1240		// Ensure user owns all pieces1241		let total_pieces = Self::total_pieces(collection.id, token).unwrap_or(u128::MAX);1242		let balance = <Balance<T>>::get((collection.id, token, owner));1243		ensure!(1244			total_pieces == balance,1245			<Error<T>>::RepartitionWhileNotOwningAllPieces1246		);12471248		<Balance<T>>::insert((collection.id, token, owner), amount);1249		<TotalSupply<T>>::insert((collection.id, token), amount);12501251		if amount > total_pieces {1252			let mint_amount = amount - total_pieces;1253			<PalletEvm<T>>::deposit_log(1254				ERC20Events::Transfer {1255					from: H160::default(),1256					to: *owner.as_eth(),1257					value: mint_amount.into(),1258				}1259				.to_log(T::EvmTokenAddressMapping::token_to_address(1260					collection.id,1261					token,1262				)),1263			);1264			<PalletCommon<T>>::deposit_event(CommonEvent::ItemCreated(1265				collection.id,1266				token,1267				owner.clone(),1268				mint_amount,1269			));1270		} else if total_pieces > amount {1271			let burn_amount = total_pieces - amount;1272			<PalletEvm<T>>::deposit_log(1273				ERC20Events::Transfer {1274					from: *owner.as_eth(),1275					to: H160::default(),1276					value: burn_amount.into(),1277				}1278				.to_log(T::EvmTokenAddressMapping::token_to_address(1279					collection.id,1280					token,1281				)),1282			);1283			<PalletCommon<T>>::deposit_event(CommonEvent::ItemDestroyed(1284				collection.id,1285				token,1286				owner.clone(),1287				burn_amount,1288			));1289		}12901291		Ok(())1292	}12931294	fn token_owner(collection_id: CollectionId, token_id: TokenId) -> Option<T::CrossAccountId> {1295		let mut owner = None;1296		let mut count = 0;1297		for key in Balance::<T>::iter_key_prefix((collection_id, token_id)) {1298			count += 1;1299			if count > 1 {1300				return None;1301			}1302			owner = Some(key);1303		}1304		owner1305	}13061307	fn total_pieces(collection_id: CollectionId, token_id: TokenId) -> Option<u128> {1308		<TotalSupply<T>>::try_get((collection_id, token_id)).ok()1309	}13101311	pub fn set_collection_properties(1312		collection: &RefungibleHandle<T>,1313		sender: &T::CrossAccountId,1314		properties: Vec<Property>,1315	) -> DispatchResult {1316		<PalletCommon<T>>::set_collection_properties(collection, sender, properties)1317	}13181319	pub fn delete_collection_properties(1320		collection: &RefungibleHandle<T>,1321		sender: &T::CrossAccountId,1322		property_keys: Vec<PropertyKey>,1323	) -> DispatchResult {1324		<PalletCommon<T>>::delete_collection_properties(collection, sender, property_keys)1325	}13261327	pub fn set_token_property_permissions(1328		collection: &RefungibleHandle<T>,1329		sender: &T::CrossAccountId,1330		property_permissions: Vec<PropertyKeyPermission>,1331	) -> DispatchResult {1332		<PalletCommon<T>>::set_token_property_permissions(collection, sender, property_permissions)1333	}13341335	/// Returns 10 token in no particular order.1336	///1337	/// There is no direct way to get token holders in ascending order,1338	/// since `iter_prefix` returns values in no particular order.1339	/// Therefore, getting the 10 largest holders with a large value of holders1340	/// can lead to impact memory allocation + sorting with  `n * log (n)`.1341	pub fn token_owners(1342		collection_id: CollectionId,1343		token: TokenId,1344	) -> Option<Vec<T::CrossAccountId>> {1345		let res: Vec<T::CrossAccountId> = <Balance<T>>::iter_prefix((collection_id, token))1346			.map(|(owner, _amount)| owner)1347			.take(10)1348			.collect();13491350		if res.is_empty() {1351			None1352		} else {1353			Some(res)1354		}1355	}1356}