# Oracle

### setExternalOracle

Defines the underlying asset symbol and oracle address for a pool. Only called by the owner.

```javascript
function setExternalOracle(string[] calldata symbols, address[] calldata oracles_) external onlyOwner 
```

**Params:**

| **Name**  | **Type** | **Description**                                   |
| --------- | -------- | ------------------------------------------------- |
| symbols   | string   | The asset symbol for which to retrieve price feed |
| oracles\_ | address  | The external oracle address                       |

### setFixPrice

Sets the price for an asset.

```javascript
function setFixPrice(string memory symbol, uint256 ts, uint256 price) external onlyOwner 
```

**Params:**

| **Name** | **Type**                                                        | **Description**                               |
| -------- | --------------------------------------------------------------- | --------------------------------------------- |
| symbol   | string The symbol of the asset for which the price is being set |                                               |
| ts       | uint256                                                         | The timestamp associated with the asset price |
| price    | uint256                                                         | The retrieved price of the asset              |

### getPriceByExternal

Gets and computes price from external oracles

```javascript
function getPriceByExternal(address cOracleAddr, uint256 ts) external view returns (uint256 price, uint256 actualTs)
```

**Params:**

| **Name**    | **Type** | **Description**                                 |
| ----------- | -------- | ----------------------------------------------- |
| cOracleAddr | address  | The contract address for a chainlink price feed |
| ts          | uint256  | Timestamp for the asset price                   |

**Returns:**

| **Name** | **Type** | **Description**                                           |
| -------- | -------- | --------------------------------------------------------- |
| price    | uint256  | The retrieved price                                       |
| actualTs | uint256  | The timestamp at which the price is updated by the oracle |

### \_getPrice

This internal helper function retrieves the underlying price from an external oracle.

```javascript
    function _getPrice(
        AggregatorV3Interface cOracle,
        uint80 id,
        uint256 ts,
        uint256 decimalDiff
    )
        private
        view
        returns (uint256 finalPrice, uint256 finalTs)
```

**Params:**

| **Name**    | **Type**              | **Description**                                        |
| ----------- | --------------------- | ------------------------------------------------------ |
| cOracle     | AggregatorV3Interface | Oracle interface for retrieving price feed             |
| id          | uint80                | The roundId using which price is retrieved             |
| ts          | uint256               | Timestamp for the asset price                          |
| decimalDiff | uint256               | Precision differences for the number of decimal places |

**Returns:**

| **Name**   | **Type** | **Description**                                           |
| ---------- | -------- | --------------------------------------------------------- |
| finalPrice | uint256  | The computed price                                        |
| finalTs    | uint256  | The timestamp at which the price is updated by the oracle |

### getCOracle

Returns the address of the chainlink oracle for an underlying asset

```javascript
function getCOracle(string memory symbol) public view returns (address)
```

**Params:**

| **Name** | **Type** | **Description**                                          |
| -------- | -------- | -------------------------------------------------------- |
| symbol   | string   | The symbol of the asset for which the price is being set |

**Returns:**

| **Type** | **Description**                                 |
| -------- | ----------------------------------------------- |
| address  | The contract address for a chainlink price feed |

### \_getPhaseIdFromRoundId

Returns the phaseId from the given roundId used by the external oracle

```javascript
function _getPhaseIdFromRoundId(uint80 roundId) internal pure returns (uint80) 
```

**Params:**

| **Name** | **Type** | **Description**   |
| -------- | -------- | ----------------- |
| roundId  | uint80   | The given roundId |

**Returns:**

| **Type** | **Description**                 |
| -------- | ------------------------------- |
| uint80   | The phaseId for the given round |

### \_getStartRoundId

Returns the start roundId given a phaseId

```javascript
function _getStartRoundId(uint80 phaseId) internal pure returns (uint80)
```

**Params:**

| **Name** | **Type** | **Description**   |
| -------- | -------- | ----------------- |
| phaseId  | uint80   | The given phaseId |

**Returns:**

| **Type** | **Description**   |
| -------- | ----------------- |
| uint80   | The start roundId |

### \_getPriceInPhase

Helper for getting the

```javascript
    function _getPriceInPhase(
        AggregatorV3Interface cOracle,
        uint80 start,
        uint80 end,
        uint256 ts,
        uint256 decimalDiff
    )
        internal
        view
        returns (uint256 price, uint256 actualTs)
```

**Params:**

| **Name**    | **Type**              | **Description**                                        |
| ----------- | --------------------- | ------------------------------------------------------ |
| cOracle     | AggregatorV3Interface | Oracle interface for retrieving price feed             |
| start       | uint80                | The start phaseId                                      |
| end         | uint80                | The end phaseId                                        |
| ts          | uint256               | Timestamp for the underlying price                     |
| decimalDiff | uint256               | Precision differences for the number of decimal places |

**Returns:**

| **Name** | **Type** | **Description**                                           |
| -------- | -------- | --------------------------------------------------------- |
| Price    | uint256  | The computed price                                        |
| actualTs | uint256  | The timestamp at which the price is updated by the oracle |