# Ethereum IBC protocol

## Deposit

If you want to send ERC20 token to the Orbit IBC contract, you should check that the token is registered

`decimal(address tokenAddr)`

Send a deposit transaction to the Orbit IBC contract on the Ethereum MAINNET/ROPSTEN 

```javascript
// deposit ETH
function deposit(address toAddr, address extraToAddr) payable public
// deposit ERC20 TOKEN
function depositToken(address token, address toAddr, uint amount, address extraToAddr) public
```

If your transaction succeed, 

```javascript
event Deposit(address tokenAddr, address addr, address toAddr, uint amount, uint depositId, address extraToAddr);
```

Deposit event occur in your transaction 

Then, Ethereum IBC operator and Validator begin to proceed this deposit

When deposit is completed in the Orbit chain, DepositValidated and BalanceChange event occur

```javascript
// EthpeggingContract
event DepositValidated(address mainAddr, address tokenAddr, address addr, address toAddr, uint amount, uint depositId, address extraToAddr)
// BalanceContract
event BalanceChange(address indexed user, bytes32 indexed tokenId, uint balance);
```

## Withdrawal

Send a withdrawal transaction to OrbitChain BalanceContract

```javascript
function withdrawBySignature(bytes32[] memory bytes32s, uint[] memory uints, address fromAddr, bytes memory destination, bytes memory comment, uint8 v) public
function withdraw(bytes32 tokenId, bytes memory destination, uint amount, bytes memory comment) public
```

Then, Ethereum IBC operator and Validator begin to proceed this withdrawal

When withdrawal is completed in Ethereum, Withdrawal event occur

```javascript
event Withdraw(address tokenAddr, address addr, address toAddr, uint amount, bytes32 whash, uint withdrawId, bytes comment);
```

## Contract Methods

### addToken

{% hint style="info" %}
Only owner address can execute this function.
{% endhint %}

{% code title="Smart Contract" %}

```javascript
function addToken(address _tokenAddr) public onlyOwner;
```

{% endcode %}

| Parameter    | Type    |             Description |
| ------------ | ------- | ----------------------: |
| tokenAddress | address | Token address to append |

### removeToken

{% hint style="info" %}
Only owner address can execute this function.
{% endhint %}

{% code title="Smart Contract" %}

```javascript
function removeToken(address _tokenAddr) public onlyOwner;
```

{% endcode %}

| Parameter    | Type    |             Description |
| ------------ | ------- | ----------------------: |
| tokenAddress | address | Token address to remove |

### relayDepositToken

{% code title="Smart Contract" %}

```javascript
function relayDepositToken(address mainAddr, address fromAddr, address toAddr, address token, uint amount, uint depositId, address extraToAddr) public;
```

{% endcode %}

| Parameter   | Type    |                                       Description |
| ----------- | ------- | ------------------------------------------------: |
| mainAddr    | address | Ethereum reserve contract address on main network |
| fromAddr    | address |                                 Address of sender |
| toAddr      | address |                    Receiver address on OrbitChain |
| token       | address |                                  Address of token |
| amount      | uint256 |                                   Amount of token |
| depositId   | uint256 |                             Identifier of deposit |
| extraToAddr | address |              Extra receiver address on OrbitChain |

### validateDepositToken

{% code title="Smart Contract" %}

```javascript
function validateDepositToken(address mainAddr, address fromAddr, address toAddr, address token, uint amount, uint depositId, address extraToAddr, address validator, uint8 v, bytes32 r, bytes32 s) public;
```

{% endcode %}

You should hash following parameters to sign or validate deposit request.

{% code title="" %}

```
sha256(mainAddr, fromAddr, toAddr, token, amount, depositId, extraToAddr);
```

{% endcode %}

| Parameter   | Type    |                                       Description |
| ----------- | ------- | ------------------------------------------------: |
| mainAddr    | address | Ethereum reserve contract address on main network |
| fromAddr    | address |                                 Address of sender |
| toAddr      | address |                    Receiver address on OrbitChain |
| token       | address |                                  Address of token |
| amount      | uint256 |                                   Amount of token |
| depositId   | uint256 |                             Identifier of deposit |
| extraToAddr | address |              Extra receiver address on OrbitChain |
| validator   | address |                       Address of signer/validator |
| v           | uint8   |                                    v of signature |
| r           | bytes32 |                                    r of signature |
| s           | bytes32 |                                    s of signature |

### checkValidateDepositToken

{% code title="Smart Contract" %}

```javascript
function checkValidateDepositToken(address mainAddr, address fromAddr, address toAddr, address token, uint amount, uint depositId, address extraToAddr) public;
```

{% endcode %}

| Parameter   | Type    |                                       Description |
| ----------- | ------- | ------------------------------------------------: |
| mainAddr    | address | Ethereum reserve contract address on main network |
| fromAddr    | address |                                 Address of sender |
| toAddr      | address |                    Receiver address on OrbitChain |
| token       | address |                                  Address of token |
| amount      | uint256 |                                   Amount of token |
| depositId   | uint256 |                             Identifier of deposit |
| extraToAddr | address |              Extra receiver address on OrbitChain |

### withdraw

{% hint style="info" %}
Only BalanceContract can execute this function.
{% endhint %}

{% code title="Smart Contract" %}

```javascript
function withdraw(uint withdrawId, address user, bytes32 tokenSummary, bytes memory destination, uint amount, bytes memory comment) public;
```

{% endcode %}

| Parameter    | Type    |                              Description |
| ------------ | ------- | ---------------------------------------: |
| withdrawId   | uint256 | Identifier of BalanceContract withdrawal |
| user         | address |             Sender address on OrbitChain |
| tokenSummary | bytes32 |                            Token summary |
| destination  | bytes   |        Address of withdrawal destination |
| uint256      | amount  |                     Amount of withdrawal |
| bytes        | comment |                               Extra data |

### withdraw

{% hint style="info" %}
Only BalanceContract can execute this function.
{% endhint %}

{% code title="Smart Contract" %}

```javascript
function withdraw(uint withdrawId, address user, address extraUser, bytes32 tokenSummary, bytes memory destination, uint amount, bytes memory comment) public;
```

{% endcode %}

| Parameter    | Type    |                                       Description |
| ------------ | ------- | ------------------------------------------------: |
| withdrawId   | uint256 |          Identifier of BalanceContract withdrawal |
| user         | address |                      Sender address on OrbitChain |
| extraUser    | address | Extra sender address on OrbitChain (for Giveback) |
| tokenSummary | bytes32 |                                     Token summary |
| destination  | bytes   |                 Address of withdrawal destination |
| uint256      | amount  |                              Amount of withdrawal |
| bytes        | comment |                                        Extra data |

### relayWithdraw

{% code title="Smart Contract" %}

```javascript
function relayWithdraw(uint withdrawId) public;
```

{% endcode %}

| Parameter  | Type    | Description |
| ---------- | ------- | ----------: |
| withdrawId | uint256 | Withdraw ID |

### validateWithdraw

{% code title="Smart Contract" %}

```javascript
function validateWithdraw(uint withdrawId, address validator, uint8 v, bytes32 r, bytes32 s) public;
```

{% endcode %}

| Parameter  | Type    |                 Description |
| ---------- | ------- | --------------------------: |
| withdrawId | uint256 |                 Withdraw ID |
| validator  | address | Address of signer/validator |

### checkValidateWithdraw

{% code title="Smart Contract" %}

```javascript
function validateWithdraw(uint withdrawId) public;
```

{% endcode %}

| Parameter  | Type    | Description |
| ---------- | ------- | ----------: |
| withdrawId | uint256 | Withdraw ID |

### \_

{% code title="Smart Contract" %}

```javascript
```

{% endcode %}

| Parameter | Type | Description |
| --------- | ---- | ----------: |
|           |      |             |