# DelayedReveal

> Delayed Reveal

Thirdweb's `DelayedReveal` is a contract extension for base NFT contracts. It lets you create batches of 'delayed-reveal' NFTs. You can learn more about the usage of delayed reveal NFTs here - <https://blog.thirdweb.com/delayed-reveal-nfts>

## Methods

### encryptDecrypt

```solidity
function encryptDecrypt(bytes data, bytes key) external pure returns (bytes result)
```

Encrypt/decrypt data on chain.

*Encrypt/decrypt given `data` with `key`. Uses inline assembly. See: <https://ethereum.stackexchange.com/questions/69825/decrypt-message-on-chain>*

#### Parameters

| Name | Type  | Description                                          |
| ---- | ----- | ---------------------------------------------------- |
| data | bytes | Bytes of data to encrypt/decrypt.                    |
| key  | bytes | Secure key used by caller for encryption/decryption. |

#### Returns

| Name   | Type  | Description                                       |
| ------ | ----- | ------------------------------------------------- |
| result | bytes | Output after encryption/decryption of given data. |

### encryptedData

```solidity
function encryptedData(uint256) external view returns (bytes)
```

*Mapping from tokenId of a batch of tokens => to delayed reveal data.*

#### Parameters

| Name | Type    | Description |
| ---- | ------- | ----------- |
| \_0  | uint256 | undefined   |

#### Returns

| Name | Type  | Description |
| ---- | ----- | ----------- |
| \_0  | bytes | undefined   |

### getRevealURI

```solidity
function getRevealURI(uint256 _batchId, bytes _key) external view returns (string revealedURI)
```

Returns revealed URI for a batch of NFTs.

*Reveal encrypted base URI for `_batchId` with caller/admin's `_key` used for encryption. Reverts if there's no encrypted URI for `_batchId`. See {encryptDecrypt}.*

#### Parameters

| Name      | Type    | Description                                                |
| --------- | ------- | ---------------------------------------------------------- |
| \_batchId | uint256 | ID of the batch for which URI is being revealed.           |
| \_key     | bytes   | Secure key used by caller/admin for encryption of baseURI. |

#### Returns

| Name        | Type   | Description         |
| ----------- | ------ | ------------------- |
| revealedURI | string | Decrypted base URI. |

### isEncryptedBatch

```solidity
function isEncryptedBatch(uint256 _batchId) external view returns (bool)
```

Returns whether the relvant batch of NFTs is subject to a delayed reveal.

*Returns `true` if `_batchId`'s base URI is encrypted.*

#### Parameters

| Name      | Type    | Description            |
| --------- | ------- | ---------------------- |
| \_batchId | uint256 | ID of a batch of NFTs. |

#### Returns

| Name | Type | Description |
| ---- | ---- | ----------- |
| \_0  | bool | undefined   |

### reveal

```solidity
function reveal(uint256 identifier, bytes key) external nonpayable returns (string revealedURI)
```

Reveals a batch of delayed reveal NFTs.

#### Parameters

| Name       | Type    | Description                                                                   |
| ---------- | ------- | ----------------------------------------------------------------------------- |
| identifier | uint256 | The ID for the batch of delayed-reveal NFTs to reveal.                        |
| key        | bytes   | The key with which the base URI for the relevant batch of NFTs was encrypted. |

#### Returns

| Name        | Type   | Description |
| ----------- | ------ | ----------- |
| revealedURI | string | undefined   |

## Events

### TokenURIRevealed

```solidity
event TokenURIRevealed(uint256 indexed index, string revealedURI)
```

#### Parameters

| Name            | Type    | Description |
| --------------- | ------- | ----------- |
| index `indexed` | uint256 | undefined   |
| revealedURI     | string  | undefined   |