git.delta.rocks / unique-network / refs/commits / 2203d0f0ed69

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//! # Structure Pallet18//!19//! The Structure pallet provides functionality for handling tokens nesting an unnesting.20//!21//! - [`Config`]22//! - [`Pallet`]23//!24//! ## Overview25//!26//! The Structure pallet provides functions for:27//!28//! - Searching for token parents, children and owners. Actual implementation of searching for29//!   parent/child is done by pallets corresponding to token's collection type.30//! - Nesting and unnesting tokens. Actual implementation of nesting is done by pallets corresponding31//!   to token's collection type.32//!33//! ### Terminology34//!35//! - **Nesting:** Setting up parent-child relationship between tokens. Nested tokens are inhereting36//!   owner from their parent. There could be multiple levels of nesting. Token couldn't be nested in37//!   it's child token i.e. parent-child relationship graph shouldn't have38//!39//! - **Parent:** Token that current token is nested in.40//!41//! - **Owner:** Account that owns the token and all nested tokens.42//!43//! ## Interface44//!45//! ### Available Functions46//!47//! - `find_parent` - Find parent of the token. It could be an account or another token.48//! - `parent_chain` - Find chain of parents of the token.49//! - `find_topmost_owner` - Find account or token in the end of the chain of parents.50//! - `check_nesting` - Check if the token could be nested in the other token51//! - `nest_if_sent_to_token` - Nest the token in the other token52//! - `unnest_if_nested` - Unnest the token from the other token5354#![cfg_attr(not(feature = "std"), no_std)]5556use pallet_common::CommonCollectionOperations;57use sp_std::collections::btree_set::BTreeSet;5859use frame_support::dispatch::{DispatchError, DispatchResult, DispatchResultWithPostInfo};60use frame_support::fail;61pub use pallet::*;62use pallet_common::{dispatch::CollectionDispatch, CollectionHandle};63use up_data_structs::{CollectionId, TokenId, mapping::TokenAddressMapping, budget::Budget};6465#[cfg(feature = "runtime-benchmarks")]66pub mod benchmarking;67pub mod weights;6869pub type SelfWeightOf<T> = <T as crate::Config>::WeightInfo;7071#[frame_support::pallet]72pub mod pallet {73	use frame_support::Parameter;74	use frame_support::dispatch::{GetDispatchInfo, UnfilteredDispatchable};75	use frame_support::pallet_prelude::*;7677	use super::*;7879	#[pallet::error]80	pub enum Error<T> {81		/// While nesting, encountered an already checked account, detecting a loop.82		OuroborosDetected,83		/// While nesting, reached the depth limit of nesting, exceeding the provided budget.84		DepthLimit,85		/// While nesting, reached the breadth limit of nesting, exceeding the provided budget.86		BreadthLimit,87		/// Couldn't find the token owner that is itself a token.88		TokenNotFound,89	}9091	#[pallet::event]92	pub enum Event<T> {93		/// Executed call on behalf of the token.94		Executed(DispatchResult),95	}9697	#[pallet::config]98	pub trait Config: frame_system::Config + pallet_common::Config {99		type WeightInfo: weights::WeightInfo;100		type Event: IsType<<Self as frame_system::Config>::Event> + From<Event<Self>>;101		type Call: Parameter + UnfilteredDispatchable<Origin = Self::Origin> + GetDispatchInfo;102	}103104	#[pallet::pallet]105	pub struct Pallet<T>(_);106107	#[pallet::call]108	impl<T: Config> Pallet<T> {109		// #[pallet::weight({110		// 	let dispatch_info = call.get_dispatch_info();111112		// 	(113		// 		dispatch_info.weight114		// 			// Cost of dereferencing parent115		// 			.saturating_add(T::DbWeight::get().reads(2 * *max_depth as Weight))116		// 			.saturating_add(4000 * *max_depth as Weight),117		// 		dispatch_info.class)118		// })]119		// pub fn execute(120		// 	origin: OriginFor<T>,121		// 	call: Box<<T as Config>::Call>,122		// 	max_depth: u32,123		// ) -> DispatchResult {124	}125}126127#[derive(PartialEq)]128pub enum Parent<CrossAccountId> {129	/// Token owned by a normal account.130	User(CrossAccountId),131	/// Could not find the token provided as the owner.132	TokenNotFound,133	/// Token owner is another token (still, the target token may not exist).134	Token(CollectionId, TokenId),135}136137impl<T: Config> Pallet<T> {138	/// Find account owning the `token` or a token that the `token` is nested in.139	///140	/// Returns the enum that have three variants:141	/// - [`User`](crate::Parent<T>::User): Contains account.142	/// - [`Token`](crate::Parent<T>::Token): Contains token id and collection id.143	/// - [`TokenNotFound`](crate::Parent<T>::TokenNotFound): Indicates that parent was not found144	pub fn find_parent(145		collection: CollectionId,146		token: TokenId,147	) -> Result<Parent<T::CrossAccountId>, DispatchError> {148		// TODO: Reduce cost by not reading collection config149		let handle = match CollectionHandle::try_get(collection) {150			Ok(v) => v,151			Err(_) => return Ok(Parent::TokenNotFound),152		};153		let handle = T::CollectionDispatch::dispatch(handle);154		let handle = handle.as_dyn();155156		Ok(match handle.token_owner(token) {157			Some(owner) => match T::CrossTokenAddressMapping::address_to_token(&owner) {158				Some((collection, token)) => Parent::Token(collection, token),159				None => Parent::User(owner),160			},161			None => Parent::TokenNotFound,162		})163	}164165	/// Get the chain of parents of a token in the nesting hierarchy166	///167	/// Returns an iterator of addresses of the owning tokens and the owning account,168	/// starting from the immediate parent token, ending with the account.169	/// Returns error if cycle is detected.170	pub fn parent_chain(171		mut collection: CollectionId,172		mut token: TokenId,173	) -> impl Iterator<Item = Result<Parent<T::CrossAccountId>, DispatchError>> {174		let mut finished = false;175		let mut visited = BTreeSet::new();176		visited.insert((collection, token));177		core::iter::from_fn(move || {178			if finished {179				return None;180			}181			let parent = Self::find_parent(collection, token);182			match parent {183				Ok(Parent::Token(new_collection, new_token)) => {184					collection = new_collection;185					token = new_token;186					if !visited.insert((new_collection, new_token)) {187						finished = true;188						return Some(Err(<Error<T>>::OuroborosDetected.into()));189					}190				}191				_ => finished = true,192			}193			Some(parent as Result<_, DispatchError>)194		})195	}196197	/// Try to dereference address, until finding top level owner198	///199	/// May return token address if parent token not yet exists200	///201	/// - `budget`: Limit for searching parents in depth.202	pub fn find_topmost_owner(203		collection: CollectionId,204		token: TokenId,205		budget: &dyn Budget,206	) -> Result<T::CrossAccountId, DispatchError> {207		let owner = Self::parent_chain(collection, token)208			.take_while(|_| budget.consume())209			.find(|p| matches!(p, Ok(Parent::User(_) | Parent::TokenNotFound)))210			.ok_or(<Error<T>>::DepthLimit)??;211212		Ok(match owner {213			Parent::User(v) => v,214			_ => fail!(<Error<T>>::TokenNotFound),215		})216	}217218	/// Find the topmost parent and check that assigning `for_nest` token as a child for219	/// `token` wouldn't create a cycle.220	///221	/// - `budget`: Limit for searching parents in depth.222	pub fn get_checked_topmost_owner(223		collection: CollectionId,224		token: TokenId,225		for_nest: Option<(CollectionId, TokenId)>,226		budget: &dyn Budget,227	) -> Result<T::CrossAccountId, DispatchError> {228		// Tried to nest token in itself229		if Some((collection, token)) == for_nest {230			return Err(<Error<T>>::OuroborosDetected.into());231		}232233		for parent in Self::parent_chain(collection, token).take_while(|_| budget.consume()) {234			match parent? {235				// Tried to nest token in chain, which has this token as one of parents236				Parent::Token(collection, token) if Some((collection, token)) == for_nest => {237					return Err(<Error<T>>::OuroborosDetected.into())238				}239				// Token is owned by other user240				Parent::User(user) => return Ok(user),241				Parent::TokenNotFound => return Err(<Error<T>>::TokenNotFound.into()),242				// Continue parent chain243				Parent::Token(_, _) => {}244			}245		}246247		Err(<Error<T>>::DepthLimit.into())248	}249250	/// Burn token and all of it's nested tokens251	///252	/// - `self_budget`: Limit for searching children in depth.253	/// - `breadth_budget`: Limit of breadth of searching children.254	pub fn burn_item_recursively(255		from: T::CrossAccountId,256		collection: CollectionId,257		token: TokenId,258		self_budget: &dyn Budget,259		breadth_budget: &dyn Budget,260	) -> DispatchResultWithPostInfo {261		let handle = <CollectionHandle<T>>::try_get(collection)?;262		let dispatch = T::CollectionDispatch::dispatch(handle);263		let dispatch = dispatch.as_dyn();264		dispatch.burn_item_recursively(from.clone(), token, self_budget, breadth_budget)265	}266267	/// Check if `token` indirectly owned by `user`268	///269	/// Returns `true` if `user` is `token`'s owner. Or If token is provided as `user` then270	/// check that `user` and `token` have same owner.271	/// Checks that assigning `for_nest` token as a child for `token` wouldn't create a cycle.272	///273	/// - `budget`: Limit for searching parents in depth.274	pub fn check_indirectly_owned(275		user: T::CrossAccountId,276		collection: CollectionId,277		token: TokenId,278		for_nest: Option<(CollectionId, TokenId)>,279		budget: &dyn Budget,280	) -> Result<bool, DispatchError> {281		let target_parent = match T::CrossTokenAddressMapping::address_to_token(&user) {282			Some((collection, token)) => Self::find_topmost_owner(collection, token, budget)?,283			None => user,284		};285286		Self::get_checked_topmost_owner(collection, token, for_nest, budget)287			.map(|indirect_owner| indirect_owner == target_parent)288	}289290	/// Checks that `under` is valid token and that `token_id` could be nested under it291	/// and that `from` is `under`'s owner292	///293	/// Returns OK if `under` is not a token294	///295	/// - `nesting_budget`: Limit for searching parents in depth.296	pub fn check_nesting(297		from: T::CrossAccountId,298		under: &T::CrossAccountId,299		collection_id: CollectionId,300		token_id: TokenId,301		nesting_budget: &dyn Budget,302	) -> DispatchResult {303		Self::try_exec_if_owner_is_valid_nft(under, |collection, parent_id| {304			collection.check_nesting(from, (collection_id, token_id), parent_id, nesting_budget)305		})306	}307308	/// Nests `token_id` under `under` token309	///310	/// Returns OK if `under` is not a token. Checks that nesting is possible.311	///312	/// - `nesting_budget`: Limit for searching parents in depth.313	pub fn nest_if_sent_to_token(314		from: T::CrossAccountId,315		under: &T::CrossAccountId,316		collection_id: CollectionId,317		token_id: TokenId,318		nesting_budget: &dyn Budget,319	) -> DispatchResult {320		Self::try_exec_if_owner_is_valid_nft(under, |collection, parent_id| {321			collection.check_nesting(from, (collection_id, token_id), parent_id, nesting_budget)?;322323			collection.nest(parent_id, (collection_id, token_id));324325			Ok(())326		})327	}328329	/// Nests `token_id` under `owner` token330	///331	/// Caller should check that nesting wouldn't cause recursion in nesting332	pub fn nest_if_sent_to_token_unchecked(333		owner: &T::CrossAccountId,334		collection_id: CollectionId,335		token_id: TokenId,336	) {337		Self::exec_if_owner_is_valid_nft(owner, |collection, parent_id| {338			collection.nest(parent_id, (collection_id, token_id))339		});340	}341342	/// Unnests `token_id` from `owner`.343	pub fn unnest_if_nested(344		owner: &T::CrossAccountId,345		collection_id: CollectionId,346		token_id: TokenId,347	) {348		Self::exec_if_owner_is_valid_nft(owner, |collection, parent_id| {349			collection.unnest(parent_id, (collection_id, token_id))350		});351	}352353	fn exec_if_owner_is_valid_nft(354		account: &T::CrossAccountId,355		action: impl FnOnce(&dyn CommonCollectionOperations<T>, TokenId),356	) {357		Self::try_exec_if_owner_is_valid_nft(account, |collection, id| {358			action(collection, id);359			Ok(())360		})361		.unwrap();362	}363364	fn try_exec_if_owner_is_valid_nft(365		account: &T::CrossAccountId,366		action: impl FnOnce(&dyn CommonCollectionOperations<T>, TokenId) -> DispatchResult,367	) -> DispatchResult {368		let account = T::CrossTokenAddressMapping::address_to_token(account);369370		if account.is_none() {371			return Ok(());372		}373374		let account = account.unwrap();375376		let handle = <CollectionHandle<T>>::try_get(account.0);377378		if handle.is_err() {379			return Ok(());380		}381382		let handle = handle.unwrap();383384		let dispatch = T::CollectionDispatch::dispatch(handle);385		let dispatch = dispatch.as_dyn();386387		action(dispatch, account.1)388	}389}