gasLimit, err := client.EstimateGas(context.Background(), ethereum.CallMsg{
		To:   &toAddress,
		Data: data,
	})

package main

import (
	"context"
	"crypto/ecdsa"
	"fmt"
	"log"
	"math/big"

	"github.com/ethereum/go-ethereum"
	"github.com/ethereum/go-ethereum/common"
	"github.com/ethereum/go-ethereum/common/hexutil"
	"github.com/ethereum/go-ethereum/core/types"
	"github.com/ethereum/go-ethereum/crypto"
	"github.com/ethereum/go-ethereum/crypto/sha3"
	"github.com/ethereum/go-ethereum/ethclient"
)

func main() {
	client, err := ethclient.Dial("http://127.0.0.1:7545")
	if err != nil {
		log.Fatal(err)
	}

	privateKey, err := crypto.HexToECDSA("51b24d0a29940af4b7f346f23b840c4c45d50ab0bb34d821cc41e766fc189016")
	if err != nil {
		log.Fatal(err)
	}

	publicKey := privateKey.Public()
	publicKeyECDSA, ok := publicKey.(*ecdsa.PublicKey)
	if !ok {
		log.Fatal("error casting public key to ECDSA")
	}

	fromAddress := crypto.PubkeyToAddress(*publicKeyECDSA)
	nonce, err := client.PendingNonceAt(context.Background(), fromAddress)
	if err != nil {
		log.Fatal(err)
	}

	value := big.NewInt(0) // in wei (0 eth)
	gasPrice, err := client.SuggestGasPrice(context.Background())
	if err != nil {
		log.Fatal(err)
	}

        // Адрес получателя
	toAddress := common.HexToAddress("0xeFDB9E216F42424B54eB591AD086F20165830ad7")

        // Адрес контракта
	tokenAddress := common.HexToAddress("0xBACeE245e9a6b1846d225d9D21B1F5E22C374741")

	transferFnSignature := []byte("transfer(address,uint256)")
	hash := sha3.NewKeccak256()
	hash.Write(transferFnSignature)
	methodID := hash.Sum(nil)[:4]
	fmt.Println(hexutil.Encode(methodID)) // 0xa9059cbb

	paddedAddress := common.LeftPadBytes(toAddress.Bytes(), 32)
	fmt.Println(hexutil.Encode(paddedAddress)) 

	amount := new(big.Int)
	amount.SetString("1000000000000000000000", 10) // 1000 tokens
	paddedAmount := common.LeftPadBytes(amount.Bytes(), 32)
	fmt.Println(hexutil.Encode(paddedAmount))

	var data []byte
	data = append(data, methodID...)
	data = append(data, paddedAddress...)
	data = append(data, paddedAmount...)

	gasLimit, err := client.EstimateGas(context.Background(), ethereum.CallMsg{
		To:   &toAddress,
		Data: data,
	})
	if err != nil {
		log.Fatal(err)
	}
	fmt.Println(gasLimit)

	tx := types.NewTransaction(nonce, tokenAddress, value, gasLimit, gasPrice, data)

	chainID, err := client.NetworkID(context.Background())
	if err != nil {
		log.Fatal(err)
	}

	signedTx, err := types.SignTx(tx, types.NewEIP155Signer(chainID), privateKey)
	if err != nil {
		log.Fatal(err)
	}

	err = client.SendTransaction(context.Background(), signedTx)
	if err != nil {
		log.Fatal(err)
	}

	fmt.Printf("tx sent: %s", signedTx.Hash().Hex())
}

	gasLimit, err := client.EstimateGas(context.Background(), ethereum.CallMsg{
		To:   &toAddress,
		Data: data,
	})