MNT Part 1: feat(types): add QuarkChain MNT account and token types

core/types/state_account.go

@@ -20,19 +20,28 @@ import (
 	"bytes"
 
 	"github.com/ethereum/go-ethereum/common"
+	qkccommon "github.com/ethereum/go-ethereum/qkc/common"
 	"github.com/ethereum/go-ethereum/rlp"
 	"github.com/holiman/uint256"
 )
 
-//go:generate go run ../../rlp/rlpgen -type StateAccount -out gen_account_rlp.go
+// NOTE: StateAccount uses a hand-written QuarkChain codec (EncodeRLP/DecodeRLP in
+// state_account_qkc.go) for the 6-element MNT account format. The rlpgen go:generate
+// directive was intentionally removed: regenerating gen_account_rlp.go would create a
+// conflicting standard 4-field codec and silently drop MntBalances / FullShardKey.
 
 // StateAccount is the Ethereum consensus representation of accounts.
 // These objects are stored in the main account trie.
 type StateAccount struct {
-	Nonce    uint64
-	Balance  *uint256.Int
-	Root     common.Hash // merkle root of the storage trie
-	CodeHash []byte
+	Nonce        uint64
+	Balance      *uint256.Int
+	Root         common.Hash // merkle root of the storage trie
+	CodeHash     []byte
+	MntBalances  *qkccommon.TokenBalances // Non-QKC balances.
+	FullShardKey uint32                   // QuarkChain shard key; set on first tx, preserved thereafter
+	// balanceUpdateCount keeps a changed zero QKC balance encoded as 00c0. Using
+	// a counter ensures that reverting one update does not clear earlier updates.
+	balanceUpdateCount uint64
 }
 
 // NewEmptyStateAccount constructs an empty state account.
@@ -50,36 +59,86 @@ func (acct *StateAccount) Copy() *StateAccount {
 	if acct.Balance != nil {
 		balance = new(uint256.Int).Set(acct.Balance)
 	}
+	var mnt *qkccommon.TokenBalances
+	if acct.MntBalances != nil {
+		mnt = acct.MntBalances.Copy()
+	}
 	return &StateAccount{
-		Nonce:    acct.Nonce,
-		Balance:  balance,
-		Root:     acct.Root,
-		CodeHash: common.CopyBytes(acct.CodeHash),
+		Nonce:              acct.Nonce,
+		Balance:            balance,
+		Root:               acct.Root,
+		CodeHash:           common.CopyBytes(acct.CodeHash),
+		MntBalances:        mnt,
+		FullShardKey:       acct.FullShardKey,
+		balanceUpdateCount: acct.balanceUpdateCount,
+	}
+}
+
+// IsBalanceUpdated reports whether the QKC balance has been explicitly updated.
+func (acct *StateAccount) IsBalanceUpdated() bool {
+	return acct.balanceUpdateCount > 0
+}
+
+// AddBalanceUpdate records a QKC balance update.
+func (acct *StateAccount) AddBalanceUpdate() {
+	acct.balanceUpdateCount++
+}
+
+// RevertBalanceUpdate removes a reverted QKC balance update.
+func (acct *StateAccount) RevertBalanceUpdate() {
+	if acct.balanceUpdateCount == 0 {
+		panic("reverting untracked QKC balance update")
+	}
+	acct.balanceUpdateCount--
+}
+
+// FinaliseBalanceUpdates keeps committed update presence without retaining
+// the number of updates from journals that can no longer be reverted.
+func (acct *StateAccount) FinaliseBalanceUpdates() {
+	if acct.balanceUpdateCount > 0 {
+		acct.balanceUpdateCount = 1
 	}
 }
 
-// SlimAccount is a modified version of an Account, where the root is replaced
-// with a byte slice. This format can be used to represent full-consensus format
-// or slim format which replaces the empty root and code hash as nil byte slice.
+// SlimAccount is the compact RLP account format used by state snapshots,
+// pathdb readers, and account iterators. To support snapshots in goshard, the
+// standard format must be extended with FullShardKey and MntBal so snapshots
+// preserve QuarkChain-specific account state. The added fields are optional
+// trailing RLP fields, keeping old snapshots readable and leaving room for
+// future extensions without changing the existing account format.
 type SlimAccount struct {
 	Nonce    uint64
 	Balance  *uint256.Int
 	Root     []byte // Nil if root equals to types.EmptyRootHash
 	CodeHash []byte // Nil if hash equals to types.EmptyCodeHash
+	// QKC-specific fields; both optional so old snapshots remain readable.
+	FullShardKey uint32 `rlp:"optional"` // QuarkChain shard key
+	MntBal       []byte `rlp:"optional"` // Non-QKC TokenBalances.SerializeToBytes output
 }
 
 // SlimAccountRLP encodes the state account in 'slim RLP' format.
 func SlimAccountRLP(account StateAccount) []byte {
 	slim := SlimAccount{
-		Nonce:   account.Nonce,
-		Balance: account.Balance,
+		Nonce:        account.Nonce,
+		Balance:      account.Balance,
+		FullShardKey: account.FullShardKey,
 	}
 	if account.Root != EmptyRootHash {
 		slim.Root = account.Root[:]
 	}
 	if !bytes.Equal(account.CodeHash, EmptyCodeHash[:]) {
 		slim.CodeHash = account.CodeHash
 	}
+	if account.MntBalances != nil {
+		mntBal, err := account.MntBalances.SerializeToBytes()
+		if err != nil {
+			panic(err)
+		}
+		slim.MntBal = mntBal
+	}
+	if len(slim.MntBal) == 0 && account.IsBalanceUpdated() {
+		slim.MntBal = []byte{0x00, 0xc0}
+	}
 	data, err := rlp.EncodeToBytes(slim)
 	if err != nil {
 		panic(err)
@@ -95,7 +154,20 @@ func FullAccount(data []byte) (*StateAccount, error) {
 		return nil, err
 	}
 	var account StateAccount
-	account.Nonce, account.Balance = slim.Nonce, slim.Balance
+	account.Nonce, account.Balance, account.FullShardKey = slim.Nonce, slim.Balance, slim.FullShardKey
+	if len(slim.MntBal) > 0 {
+		tb, err := qkccommon.NewTokenBalances(slim.MntBal)
+		if err != nil {
+			return nil, err
+		}
+		if tb.Len() == 0 {
+			// SlimAccount uses 00c0 to preserve a zero-balance update. Restore the
+			// update marker instead of creating an empty MNT balance set.
+			account.AddBalanceUpdate()
+		} else {
+			account.MntBalances = tb
+		}
+	}
 
 	// Interpret the storage root and code hash in slim format.
 	if len(slim.Root) == 0 {

core/types/state_account_qkc.go

@@ -0,0 +1,99 @@
+// Copyright 2026-2027, QuarkChain.
+
+package types
+
+import (
+	"errors"
+	"io"
+
+	"github.com/ethereum/go-ethereum/common"
+	qkccommon "github.com/ethereum/go-ethereum/qkc/common"
+	"github.com/ethereum/go-ethereum/rlp"
+	"github.com/holiman/uint256"
+)
+
+// qkcAccountRLP is the wire struct for QuarkChain's 6-element account format:
+// [Nonce, TokenBal(bytes), Root, CodeHash, FullShardKey(4B fixed), Optional].
+// TokenBal is stored as raw serialized bytes (matching pyquarkchain's `binary` type),
+// so nil encodes as 0x80 (empty string), not 0xC0 (empty list).
+type qkcAccountRLP struct {
+	Nonce        uint64
+	TokenBal     []byte // SerializeToBytes output; nil = no balances
+	Root         common.Hash
+	CodeHash     []byte
+	FullShardKey qkccommon.Uint32
+	Optional     []byte
+}
+
+// tokenBalancesForEncoding combines the split QKC and MNT balances into the
+// unified token table used by the wire format.
+func (acct *StateAccount) tokenBalancesForEncoding() *qkccommon.TokenBalances {
+	merged := qkccommon.NewEmptyTokenBalances()
+	qkcIsZero := acct.Balance == nil || acct.Balance.IsZero()
+	if !qkcIsZero || acct.IsBalanceUpdated() {
+		merged.SetValue(acct.Balance, qkccommon.DefaultTokenID)
+	}
+	if acct.MntBalances != nil && acct.MntBalances.Len() > 0 {
+		for id, bal := range acct.MntBalances.GetBalanceMap() {
+			merged.SetValue(bal, id)
+		}
+	}
+	return merged
+}
+
+// EncodeRLP implements rlp.Encoder for StateAccount using QuarkChain's
+// 6-element format. Root is always written as 32 bytes (no nil optimization).
+func (acct *StateAccount) EncodeRLP(w io.Writer) error {
+	tokenBal, err := acct.tokenBalancesForEncoding().SerializeToBytes()
+	if err != nil {
+		return err
+	}
+	qkc := &qkcAccountRLP{
+		Nonce:        acct.Nonce,
+		Root:         acct.Root,
+		CodeHash:     acct.CodeHash,
+		TokenBal:     tokenBal,
+		FullShardKey: qkccommon.Uint32(acct.FullShardKey),
+		Optional:     nil,
+	}
+	return rlp.Encode(w, qkc)
+}
+
+// DecodeRLP implements rlp.Decoder for StateAccount using QuarkChain's
+// 6-element format.
+func (acct *StateAccount) DecodeRLP(s *rlp.Stream) error {
+	raw, err := s.Raw()
+	if err != nil {
+		return err
+	}
+	var qkc qkcAccountRLP
+	if err := rlp.DecodeBytes(raw, &qkc); err != nil {
+		return err
+	}
+	acct.Nonce = qkc.Nonce
+	acct.CodeHash = qkc.CodeHash
+	acct.Root = qkc.Root
+	acct.FullShardKey = uint32(qkc.FullShardKey)
+	if len(qkc.Optional) != 0 {
+		return errors.New("unsupported non-empty QuarkChain account optional field")
+	}
+	acct.Balance = new(uint256.Int)
+	acct.MntBalances = nil
+	acct.balanceUpdateCount = 0
+	if len(qkc.TokenBal) > 0 {
+		tb, err := qkccommon.NewTokenBalances(qkc.TokenBal)
+		if err != nil {
+			return err
+		}
+		balMap := tb.GetBalanceMap()
+		qkcBal, hasQKC := balMap[qkccommon.DefaultTokenID]
+		if hasQKC {
+			acct.Balance.Set(qkcBal)
+			delete(balMap, qkccommon.DefaultTokenID)
+		}
+		if len(balMap) != 0 {
+			acct.MntBalances = qkccommon.NewTokenBalancesWithMap(balMap)
+		}
+	}
+	return nil
+}