From d9b4da31a1c9fc77325c26ba3c18b3658778091e Mon Sep 17 00:00:00 2001
From: Zsolt Felfoldi <zsfelfoldi@gmail.com>
Date: Thu, 30 May 2024 08:45:27 +0200
Subject: [PATCH] ethclient/lightclient: implement SendTransaction and
 PendingNonceAt

---
 ethclient/lightclient/lightclient.go  | 44 +++++++++++++++++++++++++++
 ethclient/lightclient/transactions.go | 15 +++++++++
 2 files changed, 59 insertions(+)

diff --git a/ethclient/lightclient/lightclient.go b/ethclient/lightclient/lightclient.go
index f11db0abfe..7c763818ed 100644
--- a/ethclient/lightclient/lightclient.go
+++ b/ethclient/lightclient/lightclient.go
@@ -241,6 +241,9 @@ func (c *Client) CodeAt(ctx context.Context, account common.Address, blockNumber
 }
 
 func (c *Client) NonceAt(ctx context.Context, account common.Address, blockNumber *big.Int) (uint64, error) {
+	if blockNumber.IsInt64() && rpc.BlockNumber(blockNumber.Int64()) == rpc.PendingBlockNumber {
+		return c.PendingNonceAt(ctx, account)
+	}
 	proof, _, err := c.state.getProof(ctx, blockNumber, account, nil, false)
 	if err != nil {
 		return 0, err
@@ -255,3 +258,44 @@ func (c *Client) BlockReceipts(ctx context.Context, blockNrOrHash rpc.BlockNumbe
 	}
 	return c.txAndReceipts.getBlockReceipts(ctx, hash)
 }
+
+// TransactionSender interface {
+func (c *Client) SendTransaction(ctx context.Context, tx *types.Transaction) error {
+	return c.txAndReceipts.sendTransaction(ctx, tx)
+	//TODO
+}
+
+// PendingStateReader interface {
+func (c *Client) PendingBalanceAt(ctx context.Context, account common.Address) (*big.Int, error) {
+	return c.BalanceAt(ctx, account, big.NewInt(int64(rpc.LatestBlockNumber)))
+	//TODO subtract upper estimate for pending tx costs?
+}
+
+func (c *Client) PendingStorageAt(ctx context.Context, account common.Address, key common.Hash) ([]byte, error) {
+	return c.StorageAt(ctx, account, key, big.NewInt(int64(rpc.LatestBlockNumber)))
+}
+
+func (c *Client) PendingCodeAt(ctx context.Context, account common.Address) ([]byte, error) {
+	return c.CodeAt(ctx, account, big.NewInt(int64(rpc.LatestBlockNumber)))
+}
+
+func (c *Client) PendingNonceAt(ctx context.Context, account common.Address) (uint64, error) {
+	nonce, err := c.NonceAt(ctx, account, big.NewInt(int64(rpc.LatestBlockNumber)))
+	if err != nil {
+		return 0, err
+	}
+	//TODO
+	return nonce, err
+}
+
+func (c *Client) PendingTransactionCount(ctx context.Context) (uint, error) {
+	return 0, nil //TODO
+}
+
+// BlockNumberReader interface {
+func (c *Client) BlockNumber(ctx context.Context) (uint64, error) {
+	if head := c.canonicalChain.getHead(); head != nil {
+		return head.BlockNumber(), nil
+	}
+	return 0, errors.New("chain head unknown")
+}
diff --git a/ethclient/lightclient/transactions.go b/ethclient/lightclient/transactions.go
index c542ba032f..d6bc7f6281 100644
--- a/ethclient/lightclient/transactions.go
+++ b/ethclient/lightclient/transactions.go
@@ -25,6 +25,7 @@ import (
 
 	"github.com/ethereum/go-ethereum"
 	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/common/hexutil"
 	"github.com/ethereum/go-ethereum/common/lru"
 	"github.com/ethereum/go-ethereum/consensus/misc/eip4844"
 	"github.com/ethereum/go-ethereum/core/types"
@@ -251,3 +252,17 @@ func (t *txAndReceipts) cacheBlockTxPositions(block *types.Block) {
 		t.txPosCache.Add(tx.Hash(), txInBlock{blockNumber: blockNumber, blockHash: blockHash, index: uint(i)})
 	}
 }
+
+func (t *txAndReceipts) sendTransaction(ctx context.Context, tx *types.Transaction) error {
+	data, err := tx.MarshalBinary()
+	if err != nil {
+		return err
+	}
+	if err := t.client.CallContext(ctx, nil, "eth_sendRawTransaction", hexutil.Encode(data)); err != nil {
+		return err
+	}
+	/*t.sentTxLock.Lock()
+	t.sentTxs[tx.]
+	t.sentTxLock.Unlock()*/
+	return nil
+}