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

# Fees

> Calculates, validates, and securely distributes royalties and fees according to economic parameters.

```rust theme={null}
use std::string;
use std::type_name;
use sui::coin;
use sui::sui;
use sage_admin::admin;
use sage_admin::apps;
```

<Tip>
  Explore this module further in the Mover Registry: @sage/admin
</Tip>

## Structs

### `Royalties`

Holds the configuration for how royalties may be paid out when fees are collected within the protocol.

```rust theme={null}
public struct Royalties has key
```

<Expandable title="Fields">
  ```rust theme={null}
    id: sui::object::UID,
    app: address,
    custom_coin_type: std::type_name::TypeName,
    partner_fee: u64,
    partner_treasury: address,
    protocol_fee: u64,
    protocol_treasury: address
  ```
</Expandable>

## Constants

Upper limit of what percentage can be collected by partner and protocol treasuries from a royalty payment, equivalent to 98%.

```rust theme={null}
const FEE_LIMIT: u64 = 9800;
```

Scale used to determine the percentage for the `FEE_LIMIT`.

```rust theme={null}
const SCALE: u64 = 10000;
```

Error encountered when attempting to set fee ranges within royalty payments that are out of bounds.

```rust theme={null}
const EInvalidFeeValue: u64 = 370;
```

## Functions

### `collect_payment`

Transfers collected payments to the protocol treasury.

```rust theme={null}
public fun collect_payment<CoinType>(custom_coin: Coin<CoinType>, sui_coin: Coin<SUI>)
```

<Expandable title="Implementation">
  ```rust theme={null}
    public fun collect_payment<CoinType> (
        custom_coin: Coin<CoinType>,
        sui_coin: Coin<SUI>
    ) {
        transfer::public_transfer(
            custom_coin,
            @treasury
        );

        transfer::public_transfer(
            sui_coin,
            @treasury
        );
    }
  ```
</Expandable>

### `distribute_payment`

Transfers collected payments to the protocol treasury.

```rust theme={null}
public fun distribute_payment<CoinType>(royalties: &Royalties, custom_payment: Coin<CoinType>, sui_payment: Coin<SUI>, recipient: address, ctx: &mut TxContext)
```

<Expandable title="Implementation">
  ```rust theme={null}
    public fun distribute_payment<CoinType> (
        royalties: &Royalties,
        custom_payment: Coin<CoinType>,
        sui_payment: Coin<SUI>,
        recipient: address,
        ctx: &mut TxContext
    ) {
        let custom_payment_value = custom_payment.value();

        let custom_payment = if (
            royalties.partner_fee > 0
        ) {
            distribute_royalty<CoinType>(
                royalties.partner_fee,
                custom_payment,
                custom_payment_value,
                royalties.partner_treasury,
                ctx
            )
        } else {
            custom_payment
        };

        let custom_payment = if (
            royalties.protocol_fee > 0
        ) {
            distribute_royalty<CoinType>(
                royalties.protocol_fee,
                custom_payment,
                custom_payment_value,
                royalties.protocol_treasury,
                ctx
            )
        } else {
            custom_payment
        };

        transfer::public_transfer(custom_payment, recipient);
        transfer::public_transfer(sui_payment, @treasury);
    }
  ```
</Expandable>