git.delta.rocks / unique-network / refs/commits / 4b7d82846fd8

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//! ### Dispatchable 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 token53//!54//! ## Assumptions55//!56//! * Total issued balanced of all accounts should be less than `Config::Balance::max_value()`.5758#![cfg_attr(not(feature = "std"), no_std)]5960use pallet_common::CommonCollectionOperations;61use sp_std::collections::btree_set::BTreeSet;6263use frame_support::dispatch::{DispatchError, DispatchResult, DispatchResultWithPostInfo};64use frame_support::fail;65pub use pallet::*;66use pallet_common::{dispatch::CollectionDispatch, CollectionHandle};67use up_data_structs::{CollectionId, TokenId, mapping::TokenAddressMapping, budget::Budget};6869#[cfg(feature = "runtime-benchmarks")]70pub mod benchmarking;71pub mod weights;7273pub type SelfWeightOf<T> = <T as crate::Config>::WeightInfo;7475#[frame_support::pallet]76pub mod pallet {77	use frame_support::Parameter;78	use frame_support::dispatch::{GetDispatchInfo, UnfilteredDispatchable};79	use frame_support::pallet_prelude::*;8081	use super::*;8283	#[pallet::error]84	pub enum Error<T> {85		/// While searched for owner, got already checked account86		OuroborosDetected,87		/// While searched for owner, encountered depth limit88		DepthLimit,89		/// While iterating over children, encountered breadth limit90		BreadthLimit,91		/// While searched for owner, found token owner by not-yet-existing token92		TokenNotFound,93	}9495	#[pallet::event]96	pub enum Event<T> {97		/// Executed call on behalf of token98		Executed(DispatchResult),99	}100101	#[pallet::config]102	pub trait Config: frame_system::Config + pallet_common::Config {103		type WeightInfo: weights::WeightInfo;104		type Event: IsType<<Self as frame_system::Config>::Event> + From<Event<Self>>;105		type Call: Parameter + UnfilteredDispatchable<Origin = Self::Origin> + GetDispatchInfo;106	}107108	#[pallet::pallet]109	pub struct Pallet<T>(_);110111	#[pallet::call]112	impl<T: Config> Pallet<T> {113		// #[pallet::weight({114		// 	let dispatch_info = call.get_dispatch_info();115116		// 	(117		// 		dispatch_info.weight118		// 			// Cost of dereferencing parent119		// 			.saturating_add(T::DbWeight::get().reads(2 * *max_depth as Weight))120		// 			.saturating_add(4000 * *max_depth as Weight),121		// 		dispatch_info.class)122		// })]123		// pub fn execute(124		// 	origin: OriginFor<T>,125		// 	call: Box<<T as Config>::Call>,126		// 	max_depth: u32,127		// ) -> DispatchResult {128	}129}130131#[derive(PartialEq)]132pub enum Parent<CrossAccountId> {133	/// Token owned by normal account134	User(CrossAccountId),135	/// Passed token not found136	TokenNotFound,137	/// Token owner is another token (target token still may not exist)138	Token(CollectionId, TokenId),139}140141impl<T: Config> Pallet<T> {142	/// Find account owning the `token` or a token that the `token` is nested in.143	///144	/// Returns the enum that have three variants:145	/// - [`User`](crate::Parent<T>::User): Contains account.146	/// - [`Token`](crate::Parent<T>::Token): Contains token id and collection id.147	/// - [`TokenNotFound`](crate::Parent<T>::TokenNotFound): Indicates that parent was not found148	pub fn find_parent(149		collection: CollectionId,150		token: TokenId,151	) -> Result<Parent<T::CrossAccountId>, DispatchError> {152		// TODO: Reduce cost by not reading collection config153		let handle = match CollectionHandle::try_get(collection) {154			Ok(v) => v,155			Err(_) => return Ok(Parent::TokenNotFound),156		};157		let handle = T::CollectionDispatch::dispatch(handle);158		let handle = handle.as_dyn();159160		Ok(match handle.token_owner(token) {161			Some(owner) => match T::CrossTokenAddressMapping::address_to_token(&owner) {162				Some((collection, token)) => Parent::Token(collection, token),163				None => Parent::User(owner),164			},165			None => Parent::TokenNotFound,166		})167	}168169	/// Find chain of parents of current token170	///171	/// Returns the parent of the current token, than the parent of the parent and so on until token without a parent172	/// is returned. Returns error if cycle is detected.173	pub fn parent_chain(174		mut collection: CollectionId,175		mut token: TokenId,176	) -> impl Iterator<Item = Result<Parent<T::CrossAccountId>, DispatchError>> {177		let mut finished = false;178		let mut visited = BTreeSet::new();179		visited.insert((collection, token));180		core::iter::from_fn(move || {181			if finished {182				return None;183			}184			let parent = Self::find_parent(collection, token);185			match parent {186				Ok(Parent::Token(new_collection, new_token)) => {187					collection = new_collection;188					token = new_token;189					if !visited.insert((new_collection, new_token)) {190						finished = true;191						return Some(Err(<Error<T>>::OuroborosDetected.into()));192					}193				}194				_ => finished = true,195			}196			Some(parent as Result<_, DispatchError>)197		})198	}199200	/// Try to dereference address, until finding top level owner201	///202	/// May return token address if parent token not yet exists203	///204	/// - `budget`: Limit for searching parents in depth.205	pub fn find_topmost_owner(206		collection: CollectionId,207		token: TokenId,208		budget: &dyn Budget,209	) -> Result<T::CrossAccountId, DispatchError> {210		let owner = Self::parent_chain(collection, token)211			.take_while(|_| budget.consume())212			.find(|p| matches!(p, Ok(Parent::User(_) | Parent::TokenNotFound)))213			.ok_or(<Error<T>>::DepthLimit)??;214215		Ok(match owner {216			Parent::User(v) => v,217			_ => fail!(<Error<T>>::TokenNotFound),218		})219	}220221	/// Find the topmost parent and check that assigning `for_nest` token as a parent for222	/// any token in the parents chain wouldn't create a cycle.223	///224	/// - `budget`: Limit for searching parents in depth.225	pub fn get_checked_topmost_owner(226		collection: CollectionId,227		token: TokenId,228		for_nest: Option<(CollectionId, TokenId)>,229		budget: &dyn Budget,230	) -> Result<T::CrossAccountId, DispatchError> {231		// Tried to nest token in itself232		if Some((collection, token)) == for_nest {233			return Err(<Error<T>>::OuroborosDetected.into());234		}235236		for parent in Self::parent_chain(collection, token).take_while(|_| budget.consume()) {237			match parent? {238				// Tried to nest token in chain, which has this token as one of parents239				Parent::Token(collection, token) if Some((collection, token)) == for_nest => {240					return Err(<Error<T>>::OuroborosDetected.into())241				}242				// Token is owned by other user243				Parent::User(user) => return Ok(user),244				Parent::TokenNotFound => return Err(<Error<T>>::TokenNotFound.into()),245				// Continue parent chain246				Parent::Token(_, _) => {}247			}248		}249250		Err(<Error<T>>::DepthLimit.into())251	}252253	/// Burn token and all of it's nested tokens254	///255	/// - `self_budget`: Limit for searching children in depth.256	/// - `breadth_budget`: Limit of breadth of searching children.257	pub fn burn_item_recursively(258		from: T::CrossAccountId,259		collection: CollectionId,260		token: TokenId,261		self_budget: &dyn Budget,262		breadth_budget: &dyn Budget,263	) -> DispatchResultWithPostInfo {264		let handle = <CollectionHandle<T>>::try_get(collection)?;265		let dispatch = T::CollectionDispatch::dispatch(handle);266		let dispatch = dispatch.as_dyn();267		dispatch.burn_item_recursively(from.clone(), token, self_budget, breadth_budget)268	}269270	/// Check if `token` indirectly owned by `user`271	///272	/// Returns `true` if `user` is `token`'s owner. Or If token is provided as `user` then273	/// check that `user` and `token` have same owner.274	/// Checks that assigning `for_nest` token as a parent for any token in the `token`'s275	/// parents chain wouldn't create a cycle.276	///277	/// - `budget`: Limit for searching parents in depth.278	pub fn check_indirectly_owned(279		user: T::CrossAccountId,280		collection: CollectionId,281		token: TokenId,282		for_nest: Option<(CollectionId, TokenId)>,283		budget: &dyn Budget,284	) -> Result<bool, DispatchError> {285		let target_parent = match T::CrossTokenAddressMapping::address_to_token(&user) {286			Some((collection, token)) => Self::find_topmost_owner(collection, token, budget)?,287			None => user,288		};289290		Self::get_checked_topmost_owner(collection, token, for_nest, budget)291			.map(|indirect_owner| indirect_owner == target_parent)292	}293294	/// Checks that `under` is valid token and that `token_id` could be nested under it295	/// and that `from` is `under`'s owner296	///297	/// Returns OK if `under` is not a token298	///299	/// - `nesting_budget`: Limit for searching parents in depth.300	pub fn check_nesting(301		from: T::CrossAccountId,302		under: &T::CrossAccountId,303		collection_id: CollectionId,304		token_id: TokenId,305		nesting_budget: &dyn Budget,306	) -> DispatchResult {307		Self::try_exec_if_owner_is_valid_nft(under, |collection, parent_id| {308			collection.check_nesting(from, (collection_id, token_id), parent_id, nesting_budget)309		})310	}311312	/// Nests `token_id` under `under` token313	///314	/// Returns OK if `under` is not a token. Checks that nesting is possible.315	///316	/// - `nesting_budget`: Limit for searching parents in depth.317	pub fn nest_if_sent_to_token(318		from: T::CrossAccountId,319		under: &T::CrossAccountId,320		collection_id: CollectionId,321		token_id: TokenId,322		nesting_budget: &dyn Budget,323	) -> DispatchResult {324		Self::try_exec_if_owner_is_valid_nft(under, |collection, parent_id| {325			collection.check_nesting(from, (collection_id, token_id), parent_id, nesting_budget)?;326327			collection.nest(parent_id, (collection_id, token_id));328329			Ok(())330		})331	}332333	/// Nests `token_id` under `owner` token334	///335	/// Caller should check that nesting wouldn't cause recursion in nesting336	pub fn nest_if_sent_to_token_unchecked(337		owner: &T::CrossAccountId,338		collection_id: CollectionId,339		token_id: TokenId,340	) {341		Self::exec_if_owner_is_valid_nft(owner, |collection, parent_id| {342			collection.nest(parent_id, (collection_id, token_id))343		});344	}345346	/// Unnests `token_id` from `owner`.347	pub fn unnest_if_nested(348		owner: &T::CrossAccountId,349		collection_id: CollectionId,350		token_id: TokenId,351	) {352		Self::exec_if_owner_is_valid_nft(owner, |collection, parent_id| {353			collection.unnest(parent_id, (collection_id, token_id))354		});355	}356357	fn exec_if_owner_is_valid_nft(358		account: &T::CrossAccountId,359		action: impl FnOnce(&dyn CommonCollectionOperations<T>, TokenId),360	) {361		Self::try_exec_if_owner_is_valid_nft(account, |collection, id| {362			action(collection, id);363			Ok(())364		})365		.unwrap();366	}367368	fn try_exec_if_owner_is_valid_nft(369		account: &T::CrossAccountId,370		action: impl FnOnce(&dyn CommonCollectionOperations<T>, TokenId) -> DispatchResult,371	) -> DispatchResult {372		let account = T::CrossTokenAddressMapping::address_to_token(account);373374		if account.is_none() {375			return Ok(());376		}377378		let account = account.unwrap();379380		let handle = <CollectionHandle<T>>::try_get(account.0);381382		if handle.is_err() {383			return Ok(());384		}385386		let handle = handle.unwrap();387388		let dispatch = T::CollectionDispatch::dispatch(handle);389		let dispatch = dispatch.as_dyn();390391		action(dispatch, account.1)392	}393}