git.delta.rocks / unique-network / refs/commits / 4fa2a42ac6ac

difftreelog

fix cargo fmt

PraetorP2022-07-11parent: #0766e08.patch.diff
in: master

1 file changed

modifiedpallets/fungible/src/lib.rsdiffbeforeafterboth
before · pallets/fungible/src/lib.rs
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//! # Fungible Pallet18//!19//! The Fungible pallet provides functionality for dealing with fungible assets.20//!21//! - [`CreateItemData`]22//! - [`Config`]23//! - [`FungibleHandle`]24//! - [`Pallet`]25//! - [`TotalSupply`]26//! - [`Balance`]27//! - [`Allowance`]28//! - [`Error`]29//!30//! ## Fungible tokens31//!32//! Fungible tokens or assets are divisible and non-unique. For instance,33//! fiat currencies like the dollar are fungible: A $1 bill34//! in New York City has the same value as a $1 bill in Miami.35//! A fungible token can also be a cryptocurrency like Bitcoin: 1 BTC is worth 1 BTC,36//! no matter where it is issued. Thus, the fungibility refers to a specific currency’s37//! ability to maintain one standard value. As well, it needs to have uniform acceptance.38//! This means that a currency’s history should not be able to affect its value,39//! and this is due to the fact that each piece that is a part of the currency is equal40//! in value when compared to every other piece of that exact same currency.41//! In the world of cryptocurrencies, this is essentially a coin or a token42//! that can be replaced by another identical coin or token, and they are43//! both mutually interchangeable. A popular implementation of fungible tokens is44//! the ERC-20 token standard.45//!46//! ### ERC-2047//!48//! The [ERC-20](https://ethereum.org/en/developers/docs/standards/tokens/erc-20/) (Ethereum Request for Comments 20), proposed by Fabian Vogelsteller in November 2015,49//! is a Token Standard that implements an API for tokens within Smart Contracts.50//!51//! Example functionalities ERC-20 provides:52//!53//! * transfer tokens from one account to another54//! * get the current token balance of an account55//! * get the total supply of the token available on the network56//! * approve whether an amount of token from an account can be spent by a third-party account57//!58//! ## Overview59//!60//! The module provides functionality for asset management of fungible asset, supports ERC-20 standart, includes:61//!62//! * Asset Issuance63//! * Asset Transferal64//! * Asset Destruction65//! * Delegated Asset Transfers66//!67//! **NOTE:** The created fungible asset always has `token_id` = 0.68//! So `tokenA` and `tokenB` will have different `collection_id`.69//!70//! ### Implementations71//!72//! The Fungible pallet provides implementations for the following traits.73//!74//! - [`WithRecorder`](pallet_evm_coder_substrate::WithRecorder):75//! - [`CommonCollectionOperations`](pallet_common::CommonCollectionOperations): Functions for dealing with collections76//!	- [`CommonWeightInfo`](pallet_common::CommonWeightInfo): Functions for retrieval of transaction weight77//! - [`CommonEvmHandler`](pallet_common::erc::CommonEvmHandler): Function for handling EVM runtime calls7879#![cfg_attr(not(feature = "std"), no_std)]8081use core::ops::Deref;82use evm_coder::ToLog;83use frame_support::{ensure};84use pallet_evm::account::CrossAccountId;85use up_data_structs::{86	AccessMode, CollectionId, TokenId, CreateCollectionData, mapping::TokenAddressMapping,87	budget::Budget,88};89use pallet_common::{90	Error as CommonError, Event as CommonEvent, Pallet as PalletCommon,91	eth::collection_id_to_address,92};93use pallet_evm::Pallet as PalletEvm;94use pallet_structure::Pallet as PalletStructure;95use pallet_evm_coder_substrate::WithRecorder;96use sp_core::H160;97use sp_runtime::{ArithmeticError, DispatchError, DispatchResult};98use sp_std::{collections::btree_map::BTreeMap};99100pub use pallet::*;101102use crate::erc::ERC20Events;103#[cfg(feature = "runtime-benchmarks")]104pub mod benchmarking;105pub mod common;106pub mod erc;107pub mod weights;108109pub type CreateItemData<T> = (<T as pallet_evm::account::Config>::CrossAccountId, u128);110pub(crate) type SelfWeightOf<T> = <T as Config>::WeightInfo;111112#[frame_support::pallet]113pub mod pallet {114	use frame_support::{Blake2_128, Blake2_128Concat, Twox64Concat, pallet_prelude::*, storage::Key};115	use up_data_structs::CollectionId;116	use super::weights::WeightInfo;117118	#[pallet::error]119	pub enum Error<T> {120		/// Not Fungible item data used to mint in Fungible collection.121		NotFungibleDataUsedToMintFungibleCollectionToken,122		/// Not default id passed as TokenId argument.123		FungibleItemsHaveNoId,124		/// Tried to set data for fungible item.125		FungibleItemsDontHaveData,126		/// Fungible token does not support nesting.127		FungibleDisallowsNesting,128		/// Setting item properties is not allowed.129		SettingPropertiesNotAllowed,130	}131132	#[pallet::config]133	pub trait Config:134		frame_system::Config + pallet_common::Config + pallet_structure::Config + pallet_evm::Config135	{136		type WeightInfo: WeightInfo;137	}138139	#[pallet::pallet]140	#[pallet::generate_store(pub(super) trait Store)]141	pub struct Pallet<T>(_);142143	/// Total amount of fungible tokens inside a collection.144	#[pallet::storage]145	pub type TotalSupply<T: Config> =146		StorageMap<Hasher = Twox64Concat, Key = CollectionId, Value = u128, QueryKind = ValueQuery>;147148	/// Amount of tokens owned by an account inside a collection.149	#[pallet::storage]150	pub type Balance<T: Config> = StorageNMap<151		Key = (152			Key<Twox64Concat, CollectionId>,153			Key<Blake2_128Concat, T::CrossAccountId>,154		),155		Value = u128,156		QueryKind = ValueQuery,157	>;158159	/// Storage for delegated assets.160	#[pallet::storage]161	pub type Allowance<T: Config> = StorageNMap<162		Key = (163			Key<Twox64Concat, CollectionId>,164			Key<Blake2_128, T::CrossAccountId>,165			Key<Blake2_128Concat, T::CrossAccountId>,166		),167		Value = u128,168		QueryKind = ValueQuery,169	>;170}171/// Handler for fungible assets.172pub struct FungibleHandle<T: Config>(pallet_common::CollectionHandle<T>);173impl<T: Config> FungibleHandle<T> {174	/// Casts [pallet_common::CollectionHandle] into [FungibleHandle].175	pub fn cast(inner: pallet_common::CollectionHandle<T>) -> Self {176		Self(inner)177	}178179	/// Casts [FungibleHandle] into [pallet_common::CollectionHandle].180	pub fn into_inner(self) -> pallet_common::CollectionHandle<T> {181		self.0182	}183	/// Returns a mutable reference to the internal [pallet_common::CollectionHandle].184	pub fn common_mut(&mut self) -> &mut pallet_common::CollectionHandle<T> {185		&mut self.0186	}187}188impl<T: Config> WithRecorder<T> for FungibleHandle<T> {189	fn recorder(&self) -> &pallet_evm_coder_substrate::SubstrateRecorder<T> {190		self.0.recorder()191	}192	fn into_recorder(self) -> pallet_evm_coder_substrate::SubstrateRecorder<T> {193		self.0.into_recorder()194	}195}196impl<T: Config> Deref for FungibleHandle<T> {197	type Target = pallet_common::CollectionHandle<T>;198199	fn deref(&self) -> &Self::Target {200		&self.0201	}202}203204/// Pallet implementation for fungible assets205impl<T: Config> Pallet<T> {206	/// Initializes the collection. Returns [CollectionId] on success, [DispatchError] otherwise.207	pub fn init_collection(208		owner: T::CrossAccountId,209		data: CreateCollectionData<T::AccountId>,210	) -> Result<CollectionId, DispatchError> {211		<PalletCommon<T>>::init_collection(owner, data, false)212	}213214	/// Destroys a collection.215	pub fn destroy_collection(216		collection: FungibleHandle<T>,217		sender: &T::CrossAccountId,218	) -> DispatchResult {219		let id = collection.id;220221		if Self::collection_has_tokens(id) {222			return Err(<CommonError<T>>::CantDestroyNotEmptyCollection.into());223		}224225		// =========226227		PalletCommon::destroy_collection(collection.0, sender)?;228229		<TotalSupply<T>>::remove(id);230		<Balance<T>>::remove_prefix((id,), None);231		<Allowance<T>>::remove_prefix((id,), None);232		Ok(())233	}234235	///Checks if collection has tokens. Return `true` if it has.236	fn collection_has_tokens(collection_id: CollectionId) -> bool {237		<TotalSupply<T>>::get(collection_id) != 0238	}239240	/// Burns the specified amount of the token. If the token balance241	/// or total supply is less than the given value,242	/// it will return [DispatchError].243	pub fn burn(244		collection: &FungibleHandle<T>,245		owner: &T::CrossAccountId,246		amount: u128,247	) -> DispatchResult {248		let total_supply = <TotalSupply<T>>::get(collection.id)249			.checked_sub(amount)250			.ok_or(<CommonError<T>>::TokenValueTooLow)?;251252		let balance = <Balance<T>>::get((collection.id, owner))253			.checked_sub(amount)254			.ok_or(<CommonError<T>>::TokenValueTooLow)?;255256		if collection.permissions.access() == AccessMode::AllowList {257			collection.check_allowlist(owner)?;258		}259260		// =========261262		if balance == 0 {263			<Balance<T>>::remove((collection.id, owner));264			<PalletStructure<T>>::unnest_if_nested(owner, collection.id, TokenId::default());265		} else {266			<Balance<T>>::insert((collection.id, owner), balance);267		}268		<TotalSupply<T>>::insert(collection.id, total_supply);269270		<PalletEvm<T>>::deposit_log(271			ERC20Events::Transfer {272				from: *owner.as_eth(),273				to: H160::default(),274				value: amount.into(),275			}276			.to_log(collection_id_to_address(collection.id)),277		);278		<PalletCommon<T>>::deposit_event(CommonEvent::ItemDestroyed(279			collection.id,280			TokenId::default(),281			owner.clone(),282			amount,283		));284		Ok(())285	}286287	/// Transfers the specified amount of tokens. Will check that288	/// the transfer is allowed for the token.289	pub fn transfer(290		collection: &FungibleHandle<T>,291		from: &T::CrossAccountId,292		to: &T::CrossAccountId,293		amount: u128,294		nesting_budget: &dyn Budget,295	) -> DispatchResult {296		ensure!(297			collection.limits.transfers_enabled(),298			<CommonError<T>>::TransferNotAllowed,299		);300301		if collection.permissions.access() == AccessMode::AllowList {302			collection.check_allowlist(from)?;303			collection.check_allowlist(to)?;304		}305		<PalletCommon<T>>::ensure_correct_receiver(to)?;306307		let balance_from = <Balance<T>>::get((collection.id, from))308			.checked_sub(amount)309			.ok_or(<CommonError<T>>::TokenValueTooLow)?;310		let balance_to = if from != to {311			Some(312				<Balance<T>>::get((collection.id, to))313					.checked_add(amount)314					.ok_or(ArithmeticError::Overflow)?,315			)316		} else {317			None318		};319320		// =========321322		<PalletStructure<T>>::nest_if_sent_to_token(323			from.clone(),324			to,325			collection.id,326			TokenId::default(),327			nesting_budget,328		)?;329330		if let Some(balance_to) = balance_to {331			// from != to332			if balance_from == 0 {333				<Balance<T>>::remove((collection.id, from));334				<PalletStructure<T>>::unnest_if_nested(from, collection.id, TokenId::default());335			} else {336				<Balance<T>>::insert((collection.id, from), balance_from);337			}338			<Balance<T>>::insert((collection.id, to), balance_to);339		}340341		<PalletEvm<T>>::deposit_log(342			ERC20Events::Transfer {343				from: *from.as_eth(),344				to: *to.as_eth(),345				value: amount.into(),346			}347			.to_log(collection_id_to_address(collection.id)),348		);349		<PalletCommon<T>>::deposit_event(CommonEvent::Transfer(350			collection.id,351			TokenId::default(),352			from.clone(),353			to.clone(),354			amount,355		));356		Ok(())357	}358359	/// Minting tokens for multiple IDs.360	pub fn create_multiple_items(361		collection: &FungibleHandle<T>,362		sender: &T::CrossAccountId,363		data: BTreeMap<T::CrossAccountId, u128>,364		nesting_budget: &dyn Budget,365	) -> DispatchResult {366		if !collection.is_owner_or_admin(sender) {367			ensure!(368				collection.permissions.mint_mode(),369				<CommonError<T>>::PublicMintingNotAllowed370			);371			collection.check_allowlist(sender)?;372373			for (owner, _) in data.iter() {374				collection.check_allowlist(owner)?;375			}376		}377378		let total_supply = data379			.iter()380			.map(|(_, v)| *v)381			.try_fold(<TotalSupply<T>>::get(collection.id), |acc, v| {382				acc.checked_add(v)383			})384			.ok_or(ArithmeticError::Overflow)?;385386		let mut balances = data;387		for (k, v) in balances.iter_mut() {388			*v = <Balance<T>>::get((collection.id, &k))389				.checked_add(*v)390				.ok_or(ArithmeticError::Overflow)?;391		}392393		for (to, _) in balances.iter() {394			<PalletStructure<T>>::check_nesting(395				sender.clone(),396				to,397				collection.id,398				TokenId::default(),399				nesting_budget,400			)?;401		}402403		// =========404405		<TotalSupply<T>>::insert(collection.id, total_supply);406		for (user, amount) in balances {407			<Balance<T>>::insert((collection.id, &user), amount);408			<PalletStructure<T>>::nest_if_sent_to_token_unchecked(409				&user,410				collection.id,411				TokenId::default(),412			);413			<PalletEvm<T>>::deposit_log(414				ERC20Events::Transfer {415					from: H160::default(),416					to: *user.as_eth(),417					value: amount.into(),418				}419				.to_log(collection_id_to_address(collection.id)),420			);421			<PalletCommon<T>>::deposit_event(CommonEvent::ItemCreated(422				collection.id,423				TokenId::default(),424				user.clone(),425				amount,426			));427		}428429		Ok(())430	}431432	fn set_allowance_unchecked(433		collection: &FungibleHandle<T>,434		owner: &T::CrossAccountId,435		spender: &T::CrossAccountId,436		amount: u128,437	) {438		if amount == 0 {439			<Allowance<T>>::remove((collection.id, owner, spender));440		} else {441			<Allowance<T>>::insert((collection.id, owner, spender), amount);442		}443444		<PalletEvm<T>>::deposit_log(445			ERC20Events::Approval {446				owner: *owner.as_eth(),447				spender: *spender.as_eth(),448				value: amount.into(),449			}450			.to_log(collection_id_to_address(collection.id)),451		);452		<PalletCommon<T>>::deposit_event(CommonEvent::Approved(453			collection.id,454			TokenId(0),455			owner.clone(),456			spender.clone(),457			amount,458		));459	}460461	/// Sets the amount of owner tokens that the spender can manage.462	pub fn set_allowance(463		collection: &FungibleHandle<T>,464		owner: &T::CrossAccountId,465		spender: &T::CrossAccountId,466		amount: u128,467	) -> DispatchResult {468		if collection.permissions.access() == AccessMode::AllowList {469			collection.check_allowlist(owner)?;470			collection.check_allowlist(spender)?;471		}472473		if <Balance<T>>::get((collection.id, owner)) < amount {474			ensure!(475				collection.ignores_owned_amount(owner),476				<CommonError<T>>::CantApproveMoreThanOwned477			);478		}479480		// =========481482		Self::set_allowance_unchecked(collection, owner, spender, amount);483		Ok(())484	}485486	fn check_allowed(487		collection: &FungibleHandle<T>,488		spender: &T::CrossAccountId,489		from: &T::CrossAccountId,490		amount: u128,491		nesting_budget: &dyn Budget,492	) -> Result<Option<u128>, DispatchError> {493		if spender.conv_eq(from) {494			return Ok(None);495		}496		if collection.permissions.access() == AccessMode::AllowList {497			// `from`, `to` checked in [`transfer`]498			collection.check_allowlist(spender)?;499		}500		if let Some(source) = T::CrossTokenAddressMapping::address_to_token(from) {501			// TODO: should collection owner be allowed to perform this transfer?502			ensure!(503				<PalletStructure<T>>::check_indirectly_owned(504					spender.clone(),505					source.0,506					source.1,507					None,508					nesting_budget509				)?,510				<CommonError<T>>::ApprovedValueTooLow,511			);512			return Ok(None);513		}514		let allowance = <Allowance<T>>::get((collection.id, from, spender)).checked_sub(amount);515		if allowance.is_none() {516			ensure!(517				collection.ignores_allowance(spender),518				<CommonError<T>>::ApprovedValueTooLow519			);520		}521522		Ok(allowance)523	}524525	/// Transfers of tokens that `from` gave to `spender` to manage, to `to` ID.526	pub fn transfer_from(527		collection: &FungibleHandle<T>,528		spender: &T::CrossAccountId,529		from: &T::CrossAccountId,530		to: &T::CrossAccountId,531		amount: u128,532		nesting_budget: &dyn Budget,533	) -> DispatchResult {534		let allowance = Self::check_allowed(collection, spender, from, amount, nesting_budget)?;535536		// =========537538		Self::transfer(collection, from, to, amount, nesting_budget)?;539		if let Some(allowance) = allowance {540			Self::set_allowance_unchecked(collection, from, spender, allowance);541		}542		Ok(())543	}544545	/// Burns managed tokens.546	pub fn burn_from(547		collection: &FungibleHandle<T>,548		spender: &T::CrossAccountId,549		from: &T::CrossAccountId,550		amount: u128,551		nesting_budget: &dyn Budget,552	) -> DispatchResult {553		let allowance = Self::check_allowed(collection, spender, from, amount, nesting_budget)?;554555		// =========556557		Self::burn(collection, from, amount)?;558		if let Some(allowance) = allowance {559			Self::set_allowance_unchecked(collection, from, spender, allowance);560		}561		Ok(())562	}563564	/// Delegated to `create_multiple_items`565	pub fn create_item(566		collection: &FungibleHandle<T>,567		sender: &T::CrossAccountId,568		data: CreateItemData<T>,569		nesting_budget: &dyn Budget,570	) -> DispatchResult {571		Self::create_multiple_items(572			collection,573			sender,574			[(data.0, data.1)].into_iter().collect(),575			nesting_budget,576		)577	}578}
after · pallets/fungible/src/lib.rs
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//! # Fungible Pallet18//!19//! The Fungible pallet provides functionality for dealing with fungible assets.20//!21//! - [`CreateItemData`]22//! - [`Config`]23//! - [`FungibleHandle`]24//! - [`Pallet`]25//! - [`TotalSupply`]26//! - [`Balance`]27//! - [`Allowance`]28//! - [`Error`]29//!30//! ## Fungible tokens31//!32//! Fungible tokens or assets are divisible and non-unique. For instance,33//! fiat currencies like the dollar are fungible: A $1 bill34//! in New York City has the same value as a $1 bill in Miami.35//! A fungible token can also be a cryptocurrency like Bitcoin: 1 BTC is worth 1 BTC,36//! no matter where it is issued. Thus, the fungibility refers to a specific currency’s37//! ability to maintain one standard value. As well, it needs to have uniform acceptance.38//! This means that a currency’s history should not be able to affect its value,39//! and this is due to the fact that each piece that is a part of the currency is equal40//! in value when compared to every other piece of that exact same currency.41//! In the world of cryptocurrencies, this is essentially a coin or a token42//! that can be replaced by another identical coin or token, and they are43//! both mutually interchangeable. A popular implementation of fungible tokens is44//! the ERC-20 token standard.45//!46//! ### ERC-2047//!48//! The [ERC-20](https://ethereum.org/en/developers/docs/standards/tokens/erc-20/) (Ethereum Request for Comments 20), proposed by Fabian Vogelsteller in November 2015,49//! is a Token Standard that implements an API for tokens within Smart Contracts.50//!51//! Example functionalities ERC-20 provides:52//!53//! * transfer tokens from one account to another54//! * get the current token balance of an account55//! * get the total supply of the token available on the network56//! * approve whether an amount of token from an account can be spent by a third-party account57//!58//! ## Overview59//!60//! The module provides functionality for asset management of fungible asset, supports ERC-20 standart, includes:61//!62//! * Asset Issuance63//! * Asset Transferal64//! * Asset Destruction65//! * Delegated Asset Transfers66//!67//! **NOTE:** The created fungible asset always has `token_id` = 0.68//! So `tokenA` and `tokenB` will have different `collection_id`.69//!70//! ### Implementations71//!72//! The Fungible pallet provides implementations for the following traits.73//!74//! - [`WithRecorder`](pallet_evm_coder_substrate::WithRecorder):75//! - [`CommonCollectionOperations`](pallet_common::CommonCollectionOperations): Functions for dealing with collections76//!	- [`CommonWeightInfo`](pallet_common::CommonWeightInfo): Functions for retrieval of transaction weight77//! - [`CommonEvmHandler`](pallet_common::erc::CommonEvmHandler): Function for handling EVM runtime calls7879#![cfg_attr(not(feature = "std"), no_std)]8081use core::ops::Deref;82use evm_coder::ToLog;83use frame_support::{ensure};84use pallet_evm::account::CrossAccountId;85use up_data_structs::{86	AccessMode, CollectionId, TokenId, CreateCollectionData, mapping::TokenAddressMapping,87	budget::Budget,88};89use pallet_common::{90	Error as CommonError, Event as CommonEvent, Pallet as PalletCommon,91	eth::collection_id_to_address,92};93use pallet_evm::Pallet as PalletEvm;94use pallet_structure::Pallet as PalletStructure;95use pallet_evm_coder_substrate::WithRecorder;96use sp_core::H160;97use sp_runtime::{ArithmeticError, DispatchError, DispatchResult};98use sp_std::{collections::btree_map::BTreeMap};99100pub use pallet::*;101102use crate::erc::ERC20Events;103#[cfg(feature = "runtime-benchmarks")]104pub mod benchmarking;105pub mod common;106pub mod erc;107pub mod weights;108109pub type CreateItemData<T> = (<T as pallet_evm::account::Config>::CrossAccountId, u128);110pub(crate) type SelfWeightOf<T> = <T as Config>::WeightInfo;111112#[frame_support::pallet]113pub mod pallet {114	use frame_support::{Blake2_128, Blake2_128Concat, Twox64Concat, pallet_prelude::*, storage::Key};115	use up_data_structs::CollectionId;116	use super::weights::WeightInfo;117118	#[pallet::error]119	pub enum Error<T> {120		/// Not Fungible item data used to mint in Fungible collection.121		NotFungibleDataUsedToMintFungibleCollectionToken,122		/// Not default id passed as TokenId argument.123		/// The default value of TokenId for Fungible collection is 0.124		FungibleItemsHaveNoId,125		/// Tried to set data for fungible item.126		FungibleItemsDontHaveData,127		/// Fungible token does not support nesting.128		FungibleDisallowsNesting,129		/// Setting item properties is not allowed.130		SettingPropertiesNotAllowed,131	}132133	#[pallet::config]134	pub trait Config:135		frame_system::Config + pallet_common::Config + pallet_structure::Config + pallet_evm::Config136	{137		type WeightInfo: WeightInfo;138	}139140	#[pallet::pallet]141	#[pallet::generate_store(pub(super) trait Store)]142	pub struct Pallet<T>(_);143144	/// Total amount of fungible tokens inside a collection.145	#[pallet::storage]146	pub type TotalSupply<T: Config> =147		StorageMap<Hasher = Twox64Concat, Key = CollectionId, Value = u128, QueryKind = ValueQuery>;148149	/// Amount of tokens owned by an account inside a collection.150	#[pallet::storage]151	pub type Balance<T: Config> = StorageNMap<152		Key = (153			Key<Twox64Concat, CollectionId>,154			Key<Blake2_128Concat, T::CrossAccountId>,155		),156		Value = u128,157		QueryKind = ValueQuery,158	>;159160	/// Storage for delegated assets.161	#[pallet::storage]162	pub type Allowance<T: Config> = StorageNMap<163		Key = (164			Key<Twox64Concat, CollectionId>,165			Key<Blake2_128, T::CrossAccountId>,166			Key<Blake2_128Concat, T::CrossAccountId>,167		),168		Value = u128,169		QueryKind = ValueQuery,170	>;171}172/// Handler for fungible assets.173pub struct FungibleHandle<T: Config>(pallet_common::CollectionHandle<T>);174impl<T: Config> FungibleHandle<T> {175	/// Casts [pallet_common::CollectionHandle] into [FungibleHandle].176	pub fn cast(inner: pallet_common::CollectionHandle<T>) -> Self {177		Self(inner)178	}179180	/// Casts [FungibleHandle] into [pallet_common::CollectionHandle].181	pub fn into_inner(self) -> pallet_common::CollectionHandle<T> {182		self.0183	}184	/// Returns a mutable reference to the internal [pallet_common::CollectionHandle].185	pub fn common_mut(&mut self) -> &mut pallet_common::CollectionHandle<T> {186		&mut self.0187	}188}189impl<T: Config> WithRecorder<T> for FungibleHandle<T> {190	fn recorder(&self) -> &pallet_evm_coder_substrate::SubstrateRecorder<T> {191		self.0.recorder()192	}193	fn into_recorder(self) -> pallet_evm_coder_substrate::SubstrateRecorder<T> {194		self.0.into_recorder()195	}196}197impl<T: Config> Deref for FungibleHandle<T> {198	type Target = pallet_common::CollectionHandle<T>;199200	fn deref(&self) -> &Self::Target {201		&self.0202	}203}204205/// Pallet implementation for fungible assets206impl<T: Config> Pallet<T> {207	/// Initializes the collection. Returns [CollectionId] on success, [DispatchError] otherwise.208	pub fn init_collection(209		owner: T::CrossAccountId,210		data: CreateCollectionData<T::AccountId>,211	) -> Result<CollectionId, DispatchError> {212		<PalletCommon<T>>::init_collection(owner, data, false)213	}214215	/// Destroys a collection.216	pub fn destroy_collection(217		collection: FungibleHandle<T>,218		sender: &T::CrossAccountId,219	) -> DispatchResult {220		let id = collection.id;221222		if Self::collection_has_tokens(id) {223			return Err(<CommonError<T>>::CantDestroyNotEmptyCollection.into());224		}225226		// =========227228		PalletCommon::destroy_collection(collection.0, sender)?;229230		<TotalSupply<T>>::remove(id);231		<Balance<T>>::remove_prefix((id,), None);232		<Allowance<T>>::remove_prefix((id,), None);233		Ok(())234	}235236	///Checks if collection has tokens. Return `true` if it has.237	fn collection_has_tokens(collection_id: CollectionId) -> bool {238		<TotalSupply<T>>::get(collection_id) != 0239	}240241	/// Burns the specified amount of the token. If the token balance242	/// or total supply is less than the given value,243	/// it will return [DispatchError].244	pub fn burn(245		collection: &FungibleHandle<T>,246		owner: &T::CrossAccountId,247		amount: u128,248	) -> DispatchResult {249		let total_supply = <TotalSupply<T>>::get(collection.id)250			.checked_sub(amount)251			.ok_or(<CommonError<T>>::TokenValueTooLow)?;252253		let balance = <Balance<T>>::get((collection.id, owner))254			.checked_sub(amount)255			.ok_or(<CommonError<T>>::TokenValueTooLow)?;256257		if collection.permissions.access() == AccessMode::AllowList {258			collection.check_allowlist(owner)?;259		}260261		// =========262263		if balance == 0 {264			<Balance<T>>::remove((collection.id, owner));265			<PalletStructure<T>>::unnest_if_nested(owner, collection.id, TokenId::default());266		} else {267			<Balance<T>>::insert((collection.id, owner), balance);268		}269		<TotalSupply<T>>::insert(collection.id, total_supply);270271		<PalletEvm<T>>::deposit_log(272			ERC20Events::Transfer {273				from: *owner.as_eth(),274				to: H160::default(),275				value: amount.into(),276			}277			.to_log(collection_id_to_address(collection.id)),278		);279		<PalletCommon<T>>::deposit_event(CommonEvent::ItemDestroyed(280			collection.id,281			TokenId::default(),282			owner.clone(),283			amount,284		));285		Ok(())286	}287288	/// Transfers the specified amount of tokens. Will check that289	/// the transfer is allowed for the token.290	pub fn transfer(291		collection: &FungibleHandle<T>,292		from: &T::CrossAccountId,293		to: &T::CrossAccountId,294		amount: u128,295		nesting_budget: &dyn Budget,296	) -> DispatchResult {297		ensure!(298			collection.limits.transfers_enabled(),299			<CommonError<T>>::TransferNotAllowed,300		);301302		if collection.permissions.access() == AccessMode::AllowList {303			collection.check_allowlist(from)?;304			collection.check_allowlist(to)?;305		}306		<PalletCommon<T>>::ensure_correct_receiver(to)?;307308		let balance_from = <Balance<T>>::get((collection.id, from))309			.checked_sub(amount)310			.ok_or(<CommonError<T>>::TokenValueTooLow)?;311		let balance_to = if from != to {312			Some(313				<Balance<T>>::get((collection.id, to))314					.checked_add(amount)315					.ok_or(ArithmeticError::Overflow)?,316			)317		} else {318			None319		};320321		// =========322323		<PalletStructure<T>>::nest_if_sent_to_token(324			from.clone(),325			to,326			collection.id,327			TokenId::default(),328			nesting_budget,329		)?;330331		if let Some(balance_to) = balance_to {332			// from != to333			if balance_from == 0 {334				<Balance<T>>::remove((collection.id, from));335				<PalletStructure<T>>::unnest_if_nested(from, collection.id, TokenId::default());336			} else {337				<Balance<T>>::insert((collection.id, from), balance_from);338			}339			<Balance<T>>::insert((collection.id, to), balance_to);340		}341342		<PalletEvm<T>>::deposit_log(343			ERC20Events::Transfer {344				from: *from.as_eth(),345				to: *to.as_eth(),346				value: amount.into(),347			}348			.to_log(collection_id_to_address(collection.id)),349		);350		<PalletCommon<T>>::deposit_event(CommonEvent::Transfer(351			collection.id,352			TokenId::default(),353			from.clone(),354			to.clone(),355			amount,356		));357		Ok(())358	}359360	/// Minting tokens for multiple IDs.361	pub fn create_multiple_items(362		collection: &FungibleHandle<T>,363		sender: &T::CrossAccountId,364		data: BTreeMap<T::CrossAccountId, u128>,365		nesting_budget: &dyn Budget,366	) -> DispatchResult {367		if !collection.is_owner_or_admin(sender) {368			ensure!(369				collection.permissions.mint_mode(),370				<CommonError<T>>::PublicMintingNotAllowed371			);372			collection.check_allowlist(sender)?;373374			for (owner, _) in data.iter() {375				collection.check_allowlist(owner)?;376			}377		}378379		let total_supply = data380			.iter()381			.map(|(_, v)| *v)382			.try_fold(<TotalSupply<T>>::get(collection.id), |acc, v| {383				acc.checked_add(v)384			})385			.ok_or(ArithmeticError::Overflow)?;386387		let mut balances = data;388		for (k, v) in balances.iter_mut() {389			*v = <Balance<T>>::get((collection.id, &k))390				.checked_add(*v)391				.ok_or(ArithmeticError::Overflow)?;392		}393394		for (to, _) in balances.iter() {395			<PalletStructure<T>>::check_nesting(396				sender.clone(),397				to,398				collection.id,399				TokenId::default(),400				nesting_budget,401			)?;402		}403404		// =========405406		<TotalSupply<T>>::insert(collection.id, total_supply);407		for (user, amount) in balances {408			<Balance<T>>::insert((collection.id, &user), amount);409			<PalletStructure<T>>::nest_if_sent_to_token_unchecked(410				&user,411				collection.id,412				TokenId::default(),413			);414			<PalletEvm<T>>::deposit_log(415				ERC20Events::Transfer {416					from: H160::default(),417					to: *user.as_eth(),418					value: amount.into(),419				}420				.to_log(collection_id_to_address(collection.id)),421			);422			<PalletCommon<T>>::deposit_event(CommonEvent::ItemCreated(423				collection.id,424				TokenId::default(),425				user.clone(),426				amount,427			));428		}429430		Ok(())431	}432433	fn set_allowance_unchecked(434		collection: &FungibleHandle<T>,435		owner: &T::CrossAccountId,436		spender: &T::CrossAccountId,437		amount: u128,438	) {439		if amount == 0 {440			<Allowance<T>>::remove((collection.id, owner, spender));441		} else {442			<Allowance<T>>::insert((collection.id, owner, spender), amount);443		}444445		<PalletEvm<T>>::deposit_log(446			ERC20Events::Approval {447				owner: *owner.as_eth(),448				spender: *spender.as_eth(),449				value: amount.into(),450			}451			.to_log(collection_id_to_address(collection.id)),452		);453		<PalletCommon<T>>::deposit_event(CommonEvent::Approved(454			collection.id,455			TokenId(0),456			owner.clone(),457			spender.clone(),458			amount,459		));460	}461462	/// Sets the amount of owner tokens that the spender can manage.463	pub fn set_allowance(464		collection: &FungibleHandle<T>,465		owner: &T::CrossAccountId,466		spender: &T::CrossAccountId,467		amount: u128,468	) -> DispatchResult {469		if collection.permissions.access() == AccessMode::AllowList {470			collection.check_allowlist(owner)?;471			collection.check_allowlist(spender)?;472		}473474		if <Balance<T>>::get((collection.id, owner)) < amount {475			ensure!(476				collection.ignores_owned_amount(owner),477				<CommonError<T>>::CantApproveMoreThanOwned478			);479		}480481		// =========482483		Self::set_allowance_unchecked(collection, owner, spender, amount);484		Ok(())485	}486487	fn check_allowed(488		collection: &FungibleHandle<T>,489		spender: &T::CrossAccountId,490		from: &T::CrossAccountId,491		amount: u128,492		nesting_budget: &dyn Budget,493	) -> Result<Option<u128>, DispatchError> {494		if spender.conv_eq(from) {495			return Ok(None);496		}497		if collection.permissions.access() == AccessMode::AllowList {498			// `from`, `to` checked in [`transfer`]499			collection.check_allowlist(spender)?;500		}501		if let Some(source) = T::CrossTokenAddressMapping::address_to_token(from) {502			// TODO: should collection owner be allowed to perform this transfer?503			ensure!(504				<PalletStructure<T>>::check_indirectly_owned(505					spender.clone(),506					source.0,507					source.1,508					None,509					nesting_budget510				)?,511				<CommonError<T>>::ApprovedValueTooLow,512			);513			return Ok(None);514		}515		let allowance = <Allowance<T>>::get((collection.id, from, spender)).checked_sub(amount);516		if allowance.is_none() {517			ensure!(518				collection.ignores_allowance(spender),519				<CommonError<T>>::ApprovedValueTooLow520			);521		}522523		Ok(allowance)524	}525526	/// Transfers of tokens that `from` gave to `spender` to manage, to `to` ID.527	pub fn transfer_from(528		collection: &FungibleHandle<T>,529		spender: &T::CrossAccountId,530		from: &T::CrossAccountId,531		to: &T::CrossAccountId,532		amount: u128,533		nesting_budget: &dyn Budget,534	) -> DispatchResult {535		let allowance = Self::check_allowed(collection, spender, from, amount, nesting_budget)?;536537		// =========538539		Self::transfer(collection, from, to, amount, nesting_budget)?;540		if let Some(allowance) = allowance {541			Self::set_allowance_unchecked(collection, from, spender, allowance);542		}543		Ok(())544	}545546	/// Burns managed tokens.547	pub fn burn_from(548		collection: &FungibleHandle<T>,549		spender: &T::CrossAccountId,550		from: &T::CrossAccountId,551		amount: u128,552		nesting_budget: &dyn Budget,553	) -> DispatchResult {554		let allowance = Self::check_allowed(collection, spender, from, amount, nesting_budget)?;555556		// =========557558		Self::burn(collection, from, amount)?;559		if let Some(allowance) = allowance {560			Self::set_allowance_unchecked(collection, from, spender, allowance);561		}562		Ok(())563	}564565	/// Delegated to `create_multiple_items`566	pub fn create_item(567		collection: &FungibleHandle<T>,568		sender: &T::CrossAccountId,569		data: CreateItemData<T>,570		nesting_budget: &dyn Budget,571	) -> DispatchResult {572		Self::create_multiple_items(573			collection,574			sender,575			[(data.0, data.1)].into_iter().collect(),576			nesting_budget,577		)578	}579}