You cannot select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

64 lines
2.0 KiB
Solidity

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC1155/extensions/ERC1155URIStorage.sol)
pragma solidity ^0.8.0;
import "../../../utils/Strings.sol";
import "../ERC1155.sol";
/**
* @dev ERC1155 token with storage based token URI management.
* Inspired by the ERC721URIStorage extension
*
* _Available since v4.6._
*/
abstract contract ERC1155URIStorage is ERC1155 {
using Strings for uint256;
// Optional base URI
string private _baseURI = "";
// Optional mapping for token URIs
mapping(uint256 => string) private _tokenURIs;
/**
* @dev See {IERC1155MetadataURI-uri}.
*
* This implementation returns the concatenation of the `_baseURI`
* and the token-specific uri if the latter is set
*
* This enables the following behaviors:
*
* - if `_tokenURIs[tokenId]` is set, then the result is the concatenation
* of `_baseURI` and `_tokenURIs[tokenId]` (keep in mind that `_baseURI`
* is empty per default);
*
* - if `_tokenURIs[tokenId]` is NOT set then we fallback to `super.uri()`
* which in most cases will contain `ERC1155._uri`;
*
* - if `_tokenURIs[tokenId]` is NOT set, and if the parents do not have a
* uri value set, then the result is empty.
*/
function uri(uint256 tokenId) public view virtual override returns (string memory) {
string memory tokenURI = _tokenURIs[tokenId];
// If token URI is set, concatenate base URI and tokenURI (via abi.encodePacked).
return bytes(tokenURI).length > 0 ? string(abi.encodePacked(_baseURI, tokenURI)) : super.uri(tokenId);
}
/**
* @dev Sets `tokenURI` as the tokenURI of `tokenId`.
*/
function _setURI(uint256 tokenId, string memory tokenURI) internal virtual {
_tokenURIs[tokenId] = tokenURI;
emit URI(uri(tokenId), tokenId);
}
/**
* @dev Sets `baseURI` as the `_baseURI` for all tokens
*/
function _setBaseURI(string memory baseURI) internal virtual {
_baseURI = baseURI;
}
}