# PolicyFacet

## PolicyFacet

This facet contract contains all the external pre-hook functions related to vToken

## Solidity API

#### mintAllowed

Checks if the account should be allowed to mint tokens in the given market

```solidity
function mintAllowed(address vToken, address minter, uint256 mintAmount) external returns (uint256)
```

**Parameters**

| Name       | Type    | Description                                                                  |
| ---------- | ------- | ---------------------------------------------------------------------------- |
| vToken     | address | The market to verify the mint against                                        |
| minter     | address | The account which would get the minted tokens                                |
| mintAmount | uint256 | The amount of underlying being supplied to the market in exchange for tokens |

**Return Values**

| Name | Type    | Description                                                                          |
| ---- | ------- | ------------------------------------------------------------------------------------ |
| \[0] | uint256 | 0 if the mint is allowed, otherwise a semi-opaque error code (See ErrorReporter.sol) |

***

#### mintVerify

Validates mint, accrues interest and updates score in prime. Reverts on rejection. May emit logs.

```solidity
function mintVerify(address vToken, address minter, uint256 actualMintAmount, uint256 mintTokens) external
```

**Parameters**

| Name             | Type    | Description                                     |
| ---------------- | ------- | ----------------------------------------------- |
| vToken           | address | Asset being minted                              |
| minter           | address | The address minting the tokens                  |
| actualMintAmount | uint256 | The amount of the underlying asset being minted |
| mintTokens       | uint256 | The number of tokens being minted               |

***

#### redeemAllowed

Checks if the account should be allowed to redeem tokens in the given market

```solidity
function redeemAllowed(address vToken, address redeemer, uint256 redeemTokens) external returns (uint256)
```

**Parameters**

| Name         | Type    | Description                                                              |
| ------------ | ------- | ------------------------------------------------------------------------ |
| vToken       | address | The market to verify the redeem against                                  |
| redeemer     | address | The account which would redeem the tokens                                |
| redeemTokens | uint256 | The number of vTokens to exchange for the underlying asset in the market |

**Return Values**

| Name | Type    | Description                                                                            |
| ---- | ------- | -------------------------------------------------------------------------------------- |
| \[0] | uint256 | 0 if the redeem is allowed, otherwise a semi-opaque error code (See ErrorReporter.sol) |

***

#### redeemVerify

Validates redeem, accrues interest and updates score in prime. Reverts on rejection. May emit logs.

```solidity
function redeemVerify(address vToken, address redeemer, uint256 redeemAmount, uint256 redeemTokens) external
```

**Parameters**

| Name         | Type    | Description                                       |
| ------------ | ------- | ------------------------------------------------- |
| vToken       | address | Asset being redeemed                              |
| redeemer     | address | The address redeeming the tokens                  |
| redeemAmount | uint256 | The amount of the underlying asset being redeemed |
| redeemTokens | uint256 | The number of tokens being redeemed               |

***

#### borrowAllowed

Checks if the account should be allowed to borrow the underlying asset of the given market

```solidity
function borrowAllowed(address vToken, address borrower, uint256 borrowAmount) external returns (uint256)
```

**Parameters**

| Name         | Type    | Description                                       |
| ------------ | ------- | ------------------------------------------------- |
| vToken       | address | The market to verify the borrow against           |
| borrower     | address | The account which would borrow the asset          |
| borrowAmount | uint256 | The amount of underlying the account would borrow |

**Return Values**

| Name | Type    | Description                                                                            |
| ---- | ------- | -------------------------------------------------------------------------------------- |
| \[0] | uint256 | 0 if the borrow is allowed, otherwise a semi-opaque error code (See ErrorReporter.sol) |

***

#### borrowVerify

Validates borrow, accrues interest and updates score in prime. Reverts on rejection. May emit logs.

```solidity
function borrowVerify(address vToken, address borrower, uint256 borrowAmount) external
```

**Parameters**

| Name         | Type    | Description                                            |
| ------------ | ------- | ------------------------------------------------------ |
| vToken       | address | Asset whose underlying is being borrowed               |
| borrower     | address | The address borrowing the underlying                   |
| borrowAmount | uint256 | The amount of the underlying asset requested to borrow |

***

#### repayBorrowAllowed

Checks if the account should be allowed to repay a borrow in the given market

```solidity
function repayBorrowAllowed(address vToken, address payer, address borrower, uint256 repayAmount) external returns (uint256)
```

**Parameters**

| Name        | Type    | Description                                                |
| ----------- | ------- | ---------------------------------------------------------- |
| vToken      | address | The market to verify the repay against                     |
| payer       | address | The account which would repay the asset                    |
| borrower    | address | The account which borrowed the asset                       |
| repayAmount | uint256 | The amount of the underlying asset the account would repay |

**Return Values**

| Name | Type    | Description                                                                           |
| ---- | ------- | ------------------------------------------------------------------------------------- |
| \[0] | uint256 | 0 if the repay is allowed, otherwise a semi-opaque error code (See ErrorReporter.sol) |

***

#### repayBorrowVerify

Validates repayBorrow, accrues interest and updates score in prime. Reverts on rejection. May emit logs.

```solidity
function repayBorrowVerify(address vToken, address payer, address borrower, uint256 actualRepayAmount, uint256 borrowerIndex) external
```

**Parameters**

| Name              | Type    | Description                           |
| ----------------- | ------- | ------------------------------------- |
| vToken            | address | Asset being repaid                    |
| payer             | address | The address repaying the borrow       |
| borrower          | address | The address of the borrower           |
| actualRepayAmount | uint256 | The amount of underlying being repaid |
| borrowerIndex     | uint256 |                                       |

***

#### liquidateBorrowAllowed

Checks if the liquidation should be allowed to occur

```solidity
function liquidateBorrowAllowed(address vTokenBorrowed, address vTokenCollateral, address liquidator, address borrower, uint256 repayAmount) external view returns (uint256)
```

**Parameters**

| Name             | Type    | Description                                                |
| ---------------- | ------- | ---------------------------------------------------------- |
| vTokenBorrowed   | address | Asset which was borrowed by the borrower                   |
| vTokenCollateral | address | Asset which was used as collateral and will be seized      |
| liquidator       | address | The address repaying the borrow and seizing the collateral |
| borrower         | address | The address of the borrower                                |
| repayAmount      | uint256 | The amount of underlying being repaid                      |

***

#### liquidateBorrowVerify

Validates liquidateBorrow, accrues interest and updates score in prime. Reverts on rejection. May emit logs.

```solidity
function liquidateBorrowVerify(address vTokenBorrowed, address vTokenCollateral, address liquidator, address borrower, uint256 actualRepayAmount, uint256 seizeTokens) external
```

**Parameters**

| Name              | Type    | Description                                                |
| ----------------- | ------- | ---------------------------------------------------------- |
| vTokenBorrowed    | address | Asset which was borrowed by the borrower                   |
| vTokenCollateral  | address | Asset which was used as collateral and will be seized      |
| liquidator        | address | The address repaying the borrow and seizing the collateral |
| borrower          | address | The address of the borrower                                |
| actualRepayAmount | uint256 | The amount of underlying being repaid                      |
| seizeTokens       | uint256 | The amount of collateral token that will be seized         |

***

#### seizeAllowed

Checks if the seizing of assets should be allowed to occur

```solidity
function seizeAllowed(address vTokenCollateral, address vTokenBorrowed, address liquidator, address borrower, uint256 seizeTokens) external returns (uint256)
```

**Parameters**

| Name             | Type    | Description                                                |
| ---------------- | ------- | ---------------------------------------------------------- |
| vTokenCollateral | address | Asset which was used as collateral and will be seized      |
| vTokenBorrowed   | address | Asset which was borrowed by the borrower                   |
| liquidator       | address | The address repaying the borrow and seizing the collateral |
| borrower         | address | The address of the borrower                                |
| seizeTokens      | uint256 | The number of collateral tokens to seize                   |

***

#### seizeVerify

Validates seize, accrues interest and updates score in prime. Reverts on rejection. May emit logs.

```solidity
function seizeVerify(address vTokenCollateral, address vTokenBorrowed, address liquidator, address borrower, uint256 seizeTokens) external
```

**Parameters**

| Name             | Type    | Description                                                |
| ---------------- | ------- | ---------------------------------------------------------- |
| vTokenCollateral | address | Asset which was used as collateral and will be seized      |
| vTokenBorrowed   | address | Asset which was borrowed by the borrower                   |
| liquidator       | address | The address repaying the borrow and seizing the collateral |
| borrower         | address | The address of the borrower                                |
| seizeTokens      | uint256 | The number of collateral tokens to seize                   |

***

#### transferAllowed

Checks if the account should be allowed to transfer tokens in the given market

```solidity
function transferAllowed(address vToken, address src, address dst, uint256 transferTokens) external returns (uint256)
```

**Parameters**

| Name           | Type    | Description                               |
| -------------- | ------- | ----------------------------------------- |
| vToken         | address | The market to verify the transfer against |
| src            | address | The account which sources the tokens      |
| dst            | address | The account which receives the tokens     |
| transferTokens | uint256 | The number of vTokens to transfer         |

**Return Values**

| Name | Type    | Description                                                                              |
| ---- | ------- | ---------------------------------------------------------------------------------------- |
| \[0] | uint256 | 0 if the transfer is allowed, otherwise a semi-opaque error code (See ErrorReporter.sol) |

***

#### transferVerify

Validates transfer, accrues interest and updates score in prime. Reverts on rejection. May emit logs.

```solidity
function transferVerify(address vToken, address src, address dst, uint256 transferTokens) external
```

**Parameters**

| Name           | Type    | Description                           |
| -------------- | ------- | ------------------------------------- |
| vToken         | address | Asset being transferred               |
| src            | address | The account which sources the tokens  |
| dst            | address | The account which receives the tokens |
| transferTokens | uint256 | The number of vTokens to transfer     |

***

#### getBorrowingPower

Alias to getAccountLiquidity to support the Isolated Lending Comptroller Interface

```solidity
function getBorrowingPower(address account) external view returns (uint256, uint256, uint256)
```

**Parameters**

| Name    | Type    | Description                   |
| ------- | ------- | ----------------------------- |
| account | address | The account get liquidity for |

**Return Values**

| Name | Type    | Description                                                                                                                                  |
| ---- | ------- | -------------------------------------------------------------------------------------------------------------------------------------------- |
| \[0] | uint256 | (possible error code (semi-opaque), account liquidity in excess of collateral requirements, account shortfall below collateral requirements) |
| \[1] | uint256 |                                                                                                                                              |
| \[2] | uint256 |                                                                                                                                              |

***

#### getAccountLiquidity

Determine the current account liquidity wrt liquidation threshold requirements

```solidity
function getAccountLiquidity(address account) external view returns (uint256, uint256, uint256)
```

**Parameters**

| Name    | Type    | Description                   |
| ------- | ------- | ----------------------------- |
| account | address | The account get liquidity for |

**Return Values**

| Name | Type    | Description                                                                                                                                                        |
| ---- | ------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| \[0] | uint256 | (possible error code (semi-opaque), account liquidity in excess of liquidation threshold requirements, account shortfall below liquidation threshold requirements) |
| \[1] | uint256 |                                                                                                                                                                    |
| \[2] | uint256 |                                                                                                                                                                    |

***

#### getHypotheticalAccountLiquidity

Determine what the account liquidity would be if the given amounts were redeemed/borrowed

```solidity
function getHypotheticalAccountLiquidity(address account, address vTokenModify, uint256 redeemTokens, uint256 borrowAmount) external view returns (uint256, uint256, uint256)
```

**Parameters**

| Name         | Type    | Description                                       |
| ------------ | ------- | ------------------------------------------------- |
| account      | address | The account to determine liquidity for            |
| vTokenModify | address | The market to hypothetically redeem/borrow in     |
| redeemTokens | uint256 | The number of tokens to hypothetically redeem     |
| borrowAmount | uint256 | The amount of underlying to hypothetically borrow |

**Return Values**

| Name | Type    | Description                                                                                                                                                            |
| ---- | ------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| \[0] | uint256 | (possible error code (semi-opaque), hypothetical account liquidity in excess of collateral requirements, hypothetical account shortfall below collateral requirements) |
| \[1] | uint256 |                                                                                                                                                                        |
| \[2] | uint256 |                                                                                                                                                                        |

***

#### \_setVenusSpeeds

Set XVS speed for a single market

```solidity
function _setVenusSpeeds(contract VToken[] vTokens, uint256[] supplySpeeds, uint256[] borrowSpeeds) external
```

**Parameters**

| Name         | Type               | Description                          |
| ------------ | ------------------ | ------------------------------------ |
| vTokens      | contract VToken\[] | The market whose XVS speed to update |
| supplySpeeds | uint256\[]         | New XVS speed for supply             |
| borrowSpeeds | uint256\[]         | New XVS speed for borrow             |

***


---

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