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// Copyright 2023 Centrifuge Foundation (centrifuge.io).
//
// This file is part of the Centrifuge chain project.
// Centrifuge is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version (see http://www.gnu.org/licenses).
// Centrifuge is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

use core::marker::PhantomData;

use frame_support::traits::Get;
use pallet_evm_precompile_balances_erc20::{Erc20BalancesPrecompile, Erc20Metadata};
use pallet_evm_precompile_blake2::Blake2F;
use pallet_evm_precompile_bn128::{Bn128Add, Bn128Mul, Bn128Pairing};
use pallet_evm_precompile_dispatch::Dispatch;
use pallet_evm_precompile_modexp::Modexp;
use pallet_evm_precompile_sha3fips::Sha3FIPS256;
use pallet_evm_precompile_simple::{ECRecover, ECRecoverPublicKey, Identity, Ripemd160, Sha256};
use precompile_utils::precompile_set::*;
use sp_core::H160;

pub struct NativeErc20Metadata<Symbol>(PhantomData<Symbol>);
impl<Symbol: Get<&'static str>> Erc20Metadata for NativeErc20Metadata<Symbol> {
	fn name() -> &'static str {
		Symbol::get()
	}

	fn symbol() -> &'static str {
		Symbol::get()
	}

	fn decimals() -> u8 {
		18
	}

	fn is_native_currency() -> bool {
		true
	}
}

type EthereumPrecompilesChecks = (AcceptDelegateCall, CallableByContract, CallableByPrecompile);

// Address numbers linked with:
// - https://docs.moonbeam.network/builders/pallets-precompiles/precompiles/overview/#precompiled-contract-addresses
// - https://github.com/centrifuge/liquidity-pools/blob/release-v1.0/src/gateway/routers/axelar/Forwarder.sol#L29

pub const LP_AXELAR_GATEWAY: u64 = 0x800;

#[precompile_utils::precompile_name_from_address]
pub type RuntimePrecompilesAt<R, Symbol> = (
	// Ethereum precompiles:
	// We allow DELEGATECALL to stay compliant with Ethereum behavior.
	PrecompileAt<AddressU64<0x1>, ECRecover, EthereumPrecompilesChecks>,
	PrecompileAt<AddressU64<0x2>, Sha256, EthereumPrecompilesChecks>,
	PrecompileAt<AddressU64<0x3>, Ripemd160, EthereumPrecompilesChecks>,
	PrecompileAt<AddressU64<0x4>, Identity, EthereumPrecompilesChecks>,
	PrecompileAt<AddressU64<0x5>, Modexp, EthereumPrecompilesChecks>,
	PrecompileAt<AddressU64<0x6>, Bn128Add, EthereumPrecompilesChecks>,
	PrecompileAt<AddressU64<0x7>, Bn128Mul, EthereumPrecompilesChecks>,
	PrecompileAt<AddressU64<0x8>, Bn128Pairing, EthereumPrecompilesChecks>,
	PrecompileAt<AddressU64<0x9>, Blake2F, EthereumPrecompilesChecks>,
	// Non-Moonbeam specific nor Ethereum precompiles:
	PrecompileAt<AddressU64<0x400>, Sha3FIPS256, (CallableByContract, CallableByPrecompile)>,
	PrecompileAt<AddressU64<0x401>, Dispatch<R>>,
	PrecompileAt<AddressU64<0x402>, ECRecoverPublicKey, (CallableByContract, CallableByPrecompile)>,
	// Moonbeam specific precompiles:
	PrecompileAt<
		AddressU64<0x802>,
		Erc20BalancesPrecompile<R, NativeErc20Metadata<Symbol>>,
		(CallableByContract, CallableByPrecompile),
	>,
	// Centrifuge specific precompiles:
	PrecompileAt<
		AddressU64<LP_AXELAR_GATEWAY>,
		pallet_axelar_router::Pallet<R>,
		CallableByContract,
	>,
);

pub type Precompiles<R, Symbol> = PrecompileSetBuilder<R, RuntimePrecompilesAt<R, Symbol>>;

pub trait H160Addresses {
	fn h160_addresses() -> impl Iterator<Item = H160>;
}

impl<R, P: PrecompileSetFragment> H160Addresses for PrecompileSetBuilder<R, P> {
	fn h160_addresses() -> impl Iterator<Item = H160> {
		P::new().used_addresses().into_iter()
	}
}

pub mod utils {
	use sp_core::H160;
	use sp_std::collections::btree_map::BTreeMap;

	use super::H160Addresses;

	// From Moonbeam:
	//   This is the simplest bytecode to revert without returning any data.
	//   We will pre-deploy it under all of our precompiles to ensure they can be
	//   called from within contracts.
	//
	//   (PUSH1 0x00 PUSH1 0x00 REVERT)
	pub const REVERT_BYTECODE: [u8; 5] = [0x60, 0x00, 0x60, 0x00, 0xFD];

	/// Initialize all required accounts for precompiles.
	/// Used for migrations
	#[allow(dead_code)]
	pub fn initialize_accounts<T>() -> (u64, u64)
	where
		T: pallet_evm::Config,
		<T as pallet_evm::Config>::PrecompilesType: H160Addresses,
	{
		let (mut reads, mut writes) = (0, 0);
		for addr in T::PrecompilesType::h160_addresses() {
			reads += 1;
			if !pallet_evm::AccountCodes::<T>::contains_key(addr) {
				writes += 1;
				pallet_evm::AccountCodes::<T>::insert(addr, REVERT_BYTECODE.to_vec());
			}
		}
		(reads, writes)
	}

	pub fn precompile_account_genesis<PrecompileSet: H160Addresses>(
	) -> BTreeMap<H160, fp_evm::GenesisAccount> {
		PrecompileSet::h160_addresses()
			.map(|addr| {
				(
					addr,
					fp_evm::GenesisAccount {
						nonce: Default::default(),
						balance: Default::default(),
						storage: Default::default(),
						code: REVERT_BYTECODE.to_vec(),
					},
				)
			})
			.collect()
	}
}