// Copyright 2016 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 vm

import (
	"github.com/ethereum/go-ethereum/common"
	"github.com/ethereum/go-ethereum/core/state"
	"github.com/ethereum/go-ethereum/core/stateless"
	"github.com/ethereum/go-ethereum/core/tracing"
	"github.com/ethereum/go-ethereum/core/types"
	"github.com/ethereum/go-ethereum/params"
	"github.com/holiman/uint256"
)

// StateDB is an EVM database for full state querying.
type StateDB interface {
	CreateAccount(common.Address)
	CreateContract(common.Address)

	SubBalance(common.Address, *uint256.Int, tracing.BalanceChangeReason) uint256.Int
	AddBalance(common.Address, *uint256.Int, tracing.BalanceChangeReason) uint256.Int
	GetBalance(common.Address) *uint256.Int

	GetNonce(common.Address) uint64
	SetNonce(common.Address, uint64, tracing.NonceChangeReason)

	GetCodeHash(common.Address) common.Hash
	GetCode(common.Address) []byte

	// SetCode sets the new code for the address, and returns the previous code, if any.
	SetCode(common.Address, []byte, tracing.CodeChangeReason) []byte
	GetCodeSize(common.Address) int

	AddRefund(uint64)
	SubRefund(uint64)
	GetRefund() uint64

	GetStateAndCommittedState(common.Address, common.Hash) (common.Hash, common.Hash)
	GetState(common.Address, common.Hash) common.Hash
	SetState(common.Address, common.Hash, common.Hash) common.Hash
	GetStorageRoot(addr common.Address) common.Hash

	GetTransientState(addr common.Address, key common.Hash) common.Hash
	SetTransientState(addr common.Address, key, value common.Hash)

	SelfDestruct(common.Address)
	HasSelfDestructed(common.Address) bool

	// Exist reports whether the given account exists in state.
	// Notably this also returns true for self-destructed accounts within the current transaction.
	Exist(common.Address) bool

	// IsNewContract reports whether the contract at the given address was deployed
	// during the current transaction.
	IsNewContract(addr common.Address) bool

	// Empty returns whether the given account is empty. Empty
	// is defined according to EIP161 (balance = nonce = code = 0).
	Empty(common.Address) bool

	AddressInAccessList(addr common.Address) bool
	SlotInAccessList(addr common.Address, slot common.Hash) (addressOk bool, slotOk bool)
	// AddAddressToAccessList adds the given address to the access list. This operation is safe to perform
	// even if the feature/fork is not active yet
	AddAddressToAccessList(addr common.Address)
	// AddSlotToAccessList adds the given (address,slot) to the access list. This operation is safe to perform
	// even if the feature/fork is not active yet
	AddSlotToAccessList(addr common.Address, slot common.Hash)

	Prepare(rules params.Rules, sender, coinbase common.Address, dest *common.Address, precompiles []common.Address, txAccesses types.AccessList)

	RevertToSnapshot(int)
	Snapshot() int

	AddLog(*types.Log)
	AddPreimage(common.Hash, []byte)

	Witness() *stateless.Witness

	AccessEvents() *state.AccessEvents

	// Finalise must be invoked at the end of a transaction
	Finalise(bool)
}