feat(v1_5_0): add OnRamp fee sweep changesets with WETH auto-unwrap

chains/evm/deployment/v1_0_0/operations/weth/weth.go

@@ -1,10 +1,18 @@
 package weth
 
 import (
+	"encoding/json"
+	"fmt"
+	"math/big"
+
 	"github.com/Masterminds/semver/v3"
+	"github.com/ethereum/go-ethereum/accounts/abi/bind"
 	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core/types"
+
 	"github.com/smartcontractkit/chainlink-ccip/chains/evm/deployment/utils/operations/contract"
 	cldf_deployment "github.com/smartcontractkit/chainlink-deployments-framework/deployment"
+	mcms_types "github.com/smartcontractkit/mcms/types"
 	"github.com/smartcontractkit/chainlink-evm/gethwrappers/shared/generated/initial/weth9"
 )
 
@@ -24,3 +32,109 @@ var Deploy = contract.NewDeploy(contract.DeployParams[ConstructorArgs]{
 	},
 	Validate: func(ConstructorArgs) error { return nil },
 })
+
+// =============================================================================
+// WETH Withdraw Operation (Unwrap WETH to Native ETH)
+// =============================================================================
+
+// WithdrawInput specifies the amount of WETH to unwrap to native ETH.
+// The native ETH will be sent to msg.sender (the MCMS timelock).
+type WithdrawInput struct {
+	Amount *big.Int // Amount in wei to unwrap
+}
+
+// Withdraw unwraps WETH to native ETH. The ETH is sent to msg.sender.
+// This operation should be called by the MCMS timelock after receiving WETH
+// from fee withdrawals.
+var Withdraw = contract.NewWrite(contract.WriteParams[WithdrawInput, *weth9.WETH9]{
+	Name:            "weth:withdraw",
+	Version:         semver.MustParse("1.0.0"),
+	Description:     "Unwraps WETH to native ETH, sending ETH to msg.sender",
+	ContractType:    ContractType,
+	ContractABI:     weth9.WETH9ABI,
+	NewContract:     weth9.NewWETH9,
+	// Always return false - withdraw is meant to be called by MCMS timelock as part of
+	// atomic batch operations (e.g., sweep-and-unwrap). The timelock receives WETH from
+	// earlier transactions in the batch, so we can't execute directly with deployer key.
+	IsAllowedCaller: func(_ *weth9.WETH9, _ *bind.CallOpts, _ common.Address, _ WithdrawInput) (bool, error) { return false, nil },
+	Validate:        func(args WithdrawInput) error { return nil },
+	CallContract: func(weth *weth9.WETH9, opts *bind.TransactOpts, args WithdrawInput) (*types.Transaction, error) {
+		return weth.Withdraw(opts, args.Amount)
+	},
+})
+
+// =============================================================================
+// WETH Balance Read Operation
+// =============================================================================
+
+// BalanceOf reads the WETH balance of an account
+var BalanceOf = contract.NewRead(contract.ReadParams[common.Address, *big.Int, *weth9.WETH9]{
+	Name:         "weth:balance-of",
+	Version:      semver.MustParse("1.0.0"),
+	Description:  "Reads the WETH balance of an account",
+	ContractType: ContractType,
+	NewContract:  weth9.NewWETH9,
+	CallContract: func(weth *weth9.WETH9, opts *bind.CallOpts, account common.Address) (*big.Int, error) {
+		return weth.BalanceOf(opts, account)
+	},
+})
+
+// =============================================================================
+// Native ETH Transfer Helper
+// =============================================================================
+
+// CreateNativeETHTransfer creates an MCMS transaction that transfers native ETH.
+// This is used after unwrapping WETH to send the native ETH to the treasury.
+// The MCMS timelock will execute this as a simple value transfer.
+func CreateNativeETHTransfer(chainSelector uint64, to common.Address, amount *big.Int) (mcms_types.BatchOperation, error) {
+	if amount == nil || amount.Sign() <= 0 {
+		return mcms_types.BatchOperation{}, fmt.Errorf("amount must be positive, got %v", amount)
+	}
+	if to == (common.Address{}) {
+		return mcms_types.BatchOperation{}, fmt.Errorf("recipient address cannot be zero")
+	}
+
+	// Create AdditionalFields with the ETH value as a number (not quoted string)
+	// MCMS expects {"value": 123} not {"value": "123"}
+	additionalFields := json.RawMessage(fmt.Sprintf(`{"value": %s}`, amount.String()))
+
+	return mcms_types.BatchOperation{
+		ChainSelector: mcms_types.ChainSelector(chainSelector),
+		Transactions: []mcms_types.Transaction{
+			{
+				OperationMetadata: mcms_types.OperationMetadata{
+					ContractType: "NativeETHTransfer",
+				},
+				To:               to.Hex(),
+				Data:             []byte{}, // Empty but non-nil for MCMS validation
+				AdditionalFields: additionalFields,
+			},
+		},
+	}, nil
+}
+
+// CreateNativeETHTransferTx creates a single Transaction for native ETH transfer.
+// Unlike CreateNativeETHTransfer (which returns BatchOperation), this returns a
+// Transaction that can be combined with other transactions in a single atomic batch.
+// Use this when building multi-step atomic operations.
+func CreateNativeETHTransferTx(to common.Address, amount *big.Int) (mcms_types.Transaction, error) {
+	if amount == nil || amount.Sign() <= 0 {
+		return mcms_types.Transaction{}, fmt.Errorf("amount must be positive, got %v", amount)
+	}
+	if to == (common.Address{}) {
+		return mcms_types.Transaction{}, fmt.Errorf("recipient address cannot be zero")
+	}
+
+	// Create AdditionalFields with the ETH value as a number (not quoted string)
+	// MCMS expects {"value": 123} not {"value": "123"}
+	additionalFields := json.RawMessage(fmt.Sprintf(`{"value": %s}`, amount.String()))
+
+	return mcms_types.Transaction{
+		OperationMetadata: mcms_types.OperationMetadata{
+			ContractType: "NativeETHTransfer",
+		},
+		To:               to.Hex(),
+		Data:             []byte{}, // Empty but non-nil for MCMS validation
+		AdditionalFields: additionalFields,
+	}, nil
+}