> ## Documentation Index
> Fetch the complete documentation index at: https://docs.mellow.finance/llms.txt
> Use this file to discover all available pages before exploring further.

# StakingModule

The `StakingModule` contract facilitates the conversion and staking of Ethereum-based tokens, specifically WETH, stETH, and wstETH. It leverages the `DefaultModule` structure whilintegrating closely with security and withdrawal management systems of Lido protocol.

### Key Features

* **Token Conversion**: Supports the conversion of WETH to stETH and subsequently to wstETH.
* **Secure Staking**: Interfaces with a `DepositSecurityModule` for secure staking operations.
* **Withdrawal Management**: Coordinates with a `WithdrawalQueue` to manage staking withdrawals.

### Constructor

* Initializes the contract with the relevant Ethereum-based token addresses and modules.
  * **Parameters**:
    * **weth\_**: Address of the WETH token.
    * **steth\_**: Address of the stETH token.
    * **wsteth\_**: Address of the wstETH token.
    * **depositSecurityModule\_**: The deposit security module for additional security during deposits.
    * **withdrawalQueue\_**: The withdrawal queue module to manage withdrawals.
    * **stakingModuleId\_**: A unique identifier for the staking module.

### Core Methods

1. **Token Conversion**
   * `convert(uint256)`: Converts a specified amount of WETH to wstETH.
     * **amount**: The amount of WETH to convert.
   * `convertAndDeposit(uint256, uint256, bytes32, bytes32, uint256, bytes, IDepositSecurityModule.Signature[])`: Converts WETH to wstETH and deposits it using the provided security parameters.
     * **amount**: The amount of WETH to convert and deposit.
     * **blockNumber**: The block number to reference for the deposit.
     * **blockHash**: The hash of the block.
     * **depositRoot**: The root of the deposit.
     * **nonce**: A nonce to ensure the uniqueness of the deposit.
     * **depositCalldata**: Additional calldata required for the deposit.
     * **sortedGuardianSignatures**: Signatures from guardians to validate the deposit.
2. **Private Helper Functions**
   * `_wethToWSteth(uint256)`: Internal function to convert WETH directly to wstETH, handling intermediate steps.
     * **amount**: The amount of WETH to convert.

### Modifiers

* **onlyDelegateCall**: Ensures that certain functions are only callable through delegate calls to prevent direct interaction that might bypass security checks.

### Error Handling

* **NotEnoughWeth**: Triggered if there is insufficient WETH for the requested operation.
* **InvalidWithdrawalQueueState**: Indicates a mismatch in the expected state of withdrawals, potentially blocking operations if the conditions are unsafe.