// Copyright 2023 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library 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 Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.

package state

// BalanceChangeReason is used to indicate the reason for a balance change, useful
// for tracing and reporting.
type BalanceChangeReason byte

const (
	BalanceChangeUnspecified BalanceChangeReason = 0

	// Issuance
	// BalanceIncreaseRewardMineUncle is a reward for mining an uncle block.
	BalanceIncreaseRewardMineUncle BalanceChangeReason = 1
	// BalanceIncreaseRewardMineBlock is a reward for mining a block.
	BalanceIncreaseRewardMineBlock BalanceChangeReason = 2
	// BalanceIncreaseWithdrawal is ether withdrawn from the beacon chain.
	BalanceChangeWithdrawal BalanceChangeReason = 3
	// BalanceIncreaseGenesisBalance is ether allocated at the genesis block.
	BalanceIncreaseGenesisBalance BalanceChangeReason = 4

	// Transaction fees
	// BalanceIncreaseRewardTransactionFee is the transaction tip increasing block builder's balance.
	BalanceIncreaseRewardTransactionFee BalanceChangeReason = 5
	// BalanceDecreaseGasBuy is spent to purchase gas for execution a transaction.
	// Part of this gas will be burnt as per EIP-1559 rules.
	BalanceDecreaseGasBuy BalanceChangeReason = 6
	// BalanceIncreaseGasReturn is ether returned for unused gas at the end of execution.
	BalanceIncreaseGasReturn BalanceChangeReason = 7

	// DAO fork
	// BalanceIncreaseDaoContract is ether sent to the DAO refund contract.
	BalanceIncreaseDaoContract BalanceChangeReason = 8
	// BalanceDecreaseDaoAccount is ether taken from a DAO account to be moved to the refund contract.
	BalanceDecreaseDaoAccount BalanceChangeReason = 9

	// BalanceChangeTransfer is ether transfered via a call.
	// it is a decrease for the sender and an increase for the recipient.
	BalanceChangeTransfer BalanceChangeReason = 10
	// BalanceChangeTouchAccount is a transfer of zero value. It is only there to
	// touch-create an account.
	BalanceChangeTouchAccount BalanceChangeReason = 11

	// BalanceIncreaseSelfdestruct is added to the recipient as indicated by a selfdestructing account.
	BalanceIncreaseSelfdestruct BalanceChangeReason = 12
	// BalanceDecreaseSelfdestruct is deducted from a contract due to self-destruct.
	BalanceDecreaseSelfdestruct BalanceChangeReason = 13
	// BalanceDecreaseSelfdestructBurn is ether that is sent to an already self-destructed
	// account within the same tx (captured at end of tx).
	// Note it doesn't account for a self-destruct which appoints itself as recipient.
	BalanceDecreaseSelfdestructBurn BalanceChangeReason = 14
)