# Nimbus

# Copyright (c) 2024 Status Research & Development GmbH

# Licensed and distributed under either of

# * MIT license (license terms in the root directory or at https://opensource.org/licenses/MIT).

# * Apache v2 license (license terms in the root directory or at https://www.apache.org/licenses/LICENSE-2.0).

# at your option. This file may not be copied, modified, or distributed except according to those terms.

{.push raises: [].}

import

std/tables,

stint,

eth/[common, rlp],

stew/results,

../nimbus/db/[core_db, state_db],

./[tree_from_witness, witness_types]

export results

type

BlockWitness* = seq[byte]

AccountData* = object

account*: Account

code* : seq[byte]

storage*: Table[UInt256, UInt256]

proc buildAccountsTableFromKeys(

db: ReadOnlyStateDB,

keys: openArray[AccountAndSlots]): TableRef[EthAddress, AccountData] {.raises: [RlpError].} =

var accounts = newTable[EthAddress, AccountData]()

for key in keys:

let account = db.getAccount(key.address)

let code = if key.codeLen > 0:

db.getTrie().parent().kvt().get(account.codeHash.data)

else: @[]

var storage = initTable[UInt256, UInt256]()

for slot in key.slots:

let slotKey = fromBytesBE(UInt256, slot)

let (slotValue, slotExists) = db.getStorage(key.address, slotKey)

if slotExists:

storage[slotKey] = slotValue

accounts[key.address] = AccountData(

account: account,

code: code,

storage: storage)

return accounts

proc verifyWitness*(

trustedStateRoot: KeccakHash,

witness: BlockWitness,

flags: WitnessFlags): Result[TableRef[EthAddress, AccountData], string] =

if witness.len() == 0:

return err("witness is empty")

let db = newCoreDbRef(LegacyDbMemory)

var tb = initTreeBuilder(witness, db, flags)

try:

let stateRoot = tb.buildTree()

if stateRoot != trustedStateRoot:

return err("witness stateRoot doesn't match trustedStateRoot")

let ac = newAccountStateDB(db, trustedStateRoot, false)

let accounts = buildAccountsTableFromKeys(ReadOnlyStateDB(ac), tb.keys)

ok(accounts)

except Exception as e:

err(e.msg)