set 1000 sats as minimum amount that can be withdrawn

x/crosschain/keeper/evm_hooks.go

@@ -20,6 +20,7 @@ import (
 	"github.com/zeta-chain/zetacore/cmd/zetacored/config"
 	"github.com/zeta-chain/zetacore/pkg/chains"
 	"github.com/zeta-chain/zetacore/pkg/coin"
+	"github.com/zeta-chain/zetacore/pkg/constant"
 	"github.com/zeta-chain/zetacore/x/crosschain/types"
 	fungibletypes "github.com/zeta-chain/zetacore/x/fungible/types"
 	observertypes "github.com/zeta-chain/zetacore/x/observer/types"
@@ -327,7 +328,7 @@ func ValidateZrc20WithdrawEvent(event *zrc20.ZRC20Withdrawal, chainID int64) err
 	// The event was parsed; that means the user has deposited tokens to the contract.
 
 	if chains.IsBitcoinChain(chainID) {
-		if event.Value.Cmp(big.NewInt(0)) <= 0 {
+		if event.Value.Cmp(big.NewInt(constant.BTCWithdrawalDustAmount)) <= 0 {
 			return fmt.Errorf("ParseZRC20WithdrawalEvent: invalid amount %s", event.Value.String())
 		}
 		addr, err := chains.DecodeBtcAddress(string(event.To), chainID)

x/crosschain/keeper/evm_hooks_test.go

@@ -15,6 +15,7 @@ import (
 
 	"github.com/zeta-chain/zetacore/cmd/zetacored/config"
 	"github.com/zeta-chain/zetacore/pkg/chains"
+	"github.com/zeta-chain/zetacore/pkg/constant"
 	keepertest "github.com/zeta-chain/zetacore/testutil/keeper"
 	"github.com/zeta-chain/zetacore/testutil/sample"
 	crosschainkeeper "github.com/zeta-chain/zetacore/x/crosschain/keeper"
@@ -169,7 +170,9 @@ func TestValidateZrc20WithdrawEvent(t *testing.T) {
 			*sample.GetValidZRC20WithdrawToBTC(t).Logs[3],
 		)
 		require.NoError(t, err)
-		btcMainNetWithdrawalEvent.Value = big.NewInt(0)
+
+		// 1000 satoshis is the minimum amount that can be withdrawn
+		btcMainNetWithdrawalEvent.Value = big.NewInt(constant.BTCWithdrawalDustAmount - 1)
 		err = crosschainkeeper.ValidateZrc20WithdrawEvent(btcMainNetWithdrawalEvent, chains.BitcoinMainnet.ChainId)
 		require.ErrorContains(t, err, "ParseZRC20WithdrawalEvent: invalid amount")
 	})