123use crate::{4 Collection, ChainLimit, CollectionById, Config, NftTransferBasket, FungibleTransferBasket,5 eth::account::EvmBackwardsAddressMapping,6};7use evm_coder::abi::AbiReader;8use frame_support::{9 storage::{StorageMap, StorageDoubleMap, StorageValue},10 traits::Currency,11};12use pallet_evm::{EVMCurrencyAdapter, WithdrawReason};13use sp_core::{H160, U256};14use sp_std::prelude::*;15use super::{16 account::CrossAccountId,17 erc::{UniqueFungibleCall, UniqueNFTCall, ERC721Call, ERC20Call, ERC721UniqueExtensionsCall},18};19use core::convert::TryInto;2021type NegativeImbalanceOf<C, T> =22 <C as Currency<<T as frame_system::Config>::AccountId>>::NegativeImbalance;2324pub struct ChargeEvmTransaction;25pub struct ChargeEvmLiquidityInfo<T>26where27 T: Config,28 T: pallet_evm::Config,29{30 who: H160,31 negative_imbalance: NegativeImbalanceOf<<T as Config>::Currency, T>,32}3334struct AnyError;3536fn try_sponsor<T: Config>(37 caller: &H160,38 collection_id: u32,39 collection: &Collection<T>,40 call: &[u8],41) -> Result<(), AnyError> {42 let (method_id, mut reader) = AbiReader::new_call(call).map_err(|_| AnyError)?;43 match &collection.mode {44 crate::CollectionMode::NFT => {45 let call: UniqueNFTCall = UniqueNFTCall::parse(method_id, &mut reader)46 .map_err(|_| AnyError)?47 .ok_or(AnyError)?;48 match call {49 UniqueNFTCall::ERC721UniqueExtensions(ERC721UniqueExtensionsCall::Transfer {50 token_id,51 ..52 })53 | UniqueNFTCall::ERC721(ERC721Call::TransferFrom { token_id, .. }) => {54 let token_id: u32 = token_id.try_into().map_err(|_| AnyError)?;55 let block_number = <frame_system::Pallet<T>>::block_number() as T::BlockNumber;56 let collection_limits = &collection.limits;57 let limit: u32 = if collection_limits.sponsor_transfer_timeout > 0 {58 collection_limits.sponsor_transfer_timeout59 } else {60 ChainLimit::get().nft_sponsor_transfer_timeout61 };6263 let mut sponsor = true;64 if <NftTransferBasket<T>>::contains_key(collection_id, token_id) {65 let last_tx_block = <NftTransferBasket<T>>::get(collection_id, token_id);66 let limit_time = last_tx_block + limit.into();67 if block_number <= limit_time {68 sponsor = false;69 }70 }71 if sponsor {72 <NftTransferBasket<T>>::insert(collection_id, token_id, block_number);73 return Ok(());74 }75 }76 _ => {}77 }78 }79 crate::CollectionMode::Fungible(_) => {80 let call: UniqueFungibleCall = UniqueFungibleCall::parse(method_id, &mut reader)81 .map_err(|_| AnyError)?82 .ok_or(AnyError)?;83 #[allow(clippy::single_match)]84 match call {85 UniqueFungibleCall::ERC20(ERC20Call::Transfer { .. }) => {86 let who = T::CrossAccountId::from_eth(*caller);87 let collection_limits = &collection.limits;88 let limit: u32 = if collection_limits.sponsor_transfer_timeout > 0 {89 collection_limits.sponsor_transfer_timeout90 } else {91 ChainLimit::get().fungible_sponsor_transfer_timeout92 };9394 let block_number = <frame_system::Pallet<T>>::block_number() as T::BlockNumber;95 let mut sponsored = true;96 if <FungibleTransferBasket<T>>::contains_key(collection_id, who.as_sub()) {97 let last_tx_block =98 <FungibleTransferBasket<T>>::get(collection_id, who.as_sub());99 let limit_time = last_tx_block + limit.into();100 if block_number <= limit_time {101 sponsored = false;102 }103 }104 if sponsored {105 <FungibleTransferBasket<T>>::insert(106 collection_id,107 who.as_sub(),108 block_number,109 );110 return Ok(());111 }112 }113 _ => {}114 }115 }116 _ => {}117 }118 Err(AnyError)119}120121impl<T> pallet_evm::OnChargeEVMTransaction<T> for ChargeEvmTransaction122where123 T: Config,124 T: pallet_evm::Config,125{126 type LiquidityInfo = Option<ChargeEvmLiquidityInfo<T>>;127128 fn withdraw_fee(129 who: &H160,130 reason: WithdrawReason,131 fee: U256,132 ) -> Result<Self::LiquidityInfo, pallet_evm::Error<T>> {133 let mut who_pays_fee = *who;134 if let WithdrawReason::Call { target, input } = &reason {135 if let Some(collection_id) = crate::eth::map_eth_to_id(target) {136 if let Some(collection) = <CollectionById<T>>::get(collection_id) {137 if let Some(sponsor) = collection.sponsorship.sponsor() {138 if try_sponsor(who, collection_id, &collection, input).is_ok() {139 who_pays_fee =140 T::EvmBackwardsAddressMapping::from_account_id(sponsor.clone());141 }142 }143 }144 }145 }146147 148 let negative_imbalance = EVMCurrencyAdapter::<<T as Config>::Currency, ()>::withdraw_fee(149 &who_pays_fee,150 reason,151 fee,152 )?;153 Ok(negative_imbalance.map(|i| ChargeEvmLiquidityInfo {154 who: who_pays_fee,155 negative_imbalance: i,156 }))157 }158159 fn correct_and_deposit_fee(160 who: &H160,161 corrected_fee: U256,162 already_withdrawn: Self::LiquidityInfo,163 ) -> Result<(), pallet_evm::Error<T>> {164 EVMCurrencyAdapter::<<T as Config>::Currency, ()>::correct_and_deposit_fee(165 &already_withdrawn.as_ref().map(|e| e.who).unwrap_or(*who),166 corrected_fee,167 already_withdrawn.map(|e| e.negative_imbalance),168 )169 }170}