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# NavImpactLib

## NavImpactLib

Provides percentage-based NAV impact validation for cross-chain transfers

*Used by both AIntents (source) and ECrosschain (destination) for consistent validation*

### EffectiveSupplyTooLow

```solidity
error EffectiveSupplyTooLow()
```

### NavImpactTooHigh

```solidity
error NavImpactTooHigh()
```

Thrown when transfer amount exceeds maximum allowed NAV impact

*Impact is calculated as (transferValue \* 10000) / totalAssetsValue in basis points*

### MINIMUM\_SUPPLY\_RATIO

```solidity
uint256 MINIMUM_SUPPLY_RATIO
```

Minimum ratio of effective supply to total supply (1/20 = 5%)

*When virtual supply is negative, effective supply must be at least totalSupply / MINIMUM\_SUPPLY\_RATIO*

### validateNavImpact

```solidity
function validateNavImpact(address token, uint256 amount, uint256 toleranceBps) internal view
```

Validates that transfer amount doesn't exceed NAV impact tolerance

*Calculates percentage impact: (transferValue \* 10000) / totalAssetsValue vs toleranceBps*

#### Parameters

| Name         | Type    | Description                                                   |
| ------------ | ------- | ------------------------------------------------------------- |
| token        | address | Token being transferred                                       |
| amount       | uint256 | Amount being transferred                                      |
| toleranceBps | uint256 | Maximum allowed NAV impact in basis points (e.g., 1000 = 10%) |

### validateSupply

```solidity
function validateSupply(uint256 totalSupply, int256 virtualSupply) internal pure
```

Validates that effective supply meets minimum threshold when virtual supply is negative