1#![cfg_attr(not(feature = "std"), no_std)]23pub use pallet::*;4use up_evm_mapping::EvmBackwardsAddressMapping;56#[frame_support::pallet]7pub mod pallet {8 use core::marker::PhantomData;9 use frame_support::traits::Currency;10 use pallet_evm::EVMCurrencyAdapter;11 use fp_evm::WithdrawReason;12 use sp_core::{H160, U256};13 use sp_runtime::TransactionOutcome;14 use up_sponsorship::SponsorshipHandler;15 use sp_std::vec::Vec;1617 type NegativeImbalanceOf<C, T> =18 <C as Currency<<T as frame_system::Config>::AccountId>>::NegativeImbalance;1920 #[pallet::config]21 pub trait Config: frame_system::Config {22 type SponsorshipHandler: SponsorshipHandler<H160, (H160, Vec<u8>)>;23 type Currency: Currency<Self::AccountId>;24 type EvmBackwardsAddressMapping: EvmBackwardsAddressMapping<Self::AccountId>;25 }2627 #[pallet::pallet]28 #[pallet::generate_store(pub(super) trait Store)]29 pub struct Pallet<T>(_);3031 pub struct ChargeEvmLiquidityInfo<T>32 where33 T: Config,34 T: pallet_evm::Config,35 {36 who: H160,37 negative_imbalance: NegativeImbalanceOf<<T as Config>::Currency, T>,38 }3940 pub struct TransactionValidityHack<T: Config>(PhantomData<*const T>);41 impl<T: Config> fp_evm::TransactionValidityHack for TransactionValidityHack<T> {42 fn who_pays_fee(origin: H160, reason: &WithdrawReason) -> Option<H160> {43 match reason {44 WithdrawReason::Call { target, input } => {45 46 frame_support::storage::with_transaction(|| {47 TransactionOutcome::Rollback(T::SponsorshipHandler::get_sponsor(48 &origin,49 &(*target, input.clone()),50 ))51 })52 }53 _ => None,54 }55 }56 }5758 pub struct OnChargeTransaction<T: Config>(PhantomData<*const T>);59 impl<T> pallet_evm::OnChargeEVMTransaction<T> for OnChargeTransaction<T>60 where61 T: Config,62 T: pallet_evm::Config,63 {64 type LiquidityInfo = Option<ChargeEvmLiquidityInfo<T>>;6566 fn withdraw_fee(67 who: &H160,68 reason: WithdrawReason,69 fee: U256,70 ) -> core::result::Result<Self::LiquidityInfo, pallet_evm::Error<T>> {71 let mut who_pays_fee = *who;72 if let WithdrawReason::Call { target, input } = &reason {73 who_pays_fee = T::SponsorshipHandler::get_sponsor(who, &(*target, input.clone()))74 .unwrap_or(who_pays_fee);75 }76 let negative_imbalance =77 EVMCurrencyAdapter::<<T as Config>::Currency, ()>::withdraw_fee(78 &who_pays_fee,79 reason,80 fee,81 )?;82 Ok(negative_imbalance.map(|i| ChargeEvmLiquidityInfo {83 who: who_pays_fee,84 negative_imbalance: i,85 }))86 }8788 fn correct_and_deposit_fee(89 who: &H160,90 corrected_fee: U256,91 already_withdrawn: Self::LiquidityInfo,92 ) {93 <EVMCurrencyAdapter<<T as Config>::Currency, ()> as pallet_evm::OnChargeEVMTransaction<T>>::correct_and_deposit_fee(94 &already_withdrawn.as_ref().map(|e| e.who).unwrap_or(*who),95 corrected_fee,96 already_withdrawn.map(|e| e.negative_imbalance),97 )98 }99 }100}