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@farzaa
Created September 25, 2021 00:39
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pragma solidity 0.8.0;
import "@openzeppelin/contracts/utils/Strings.sol";
import "@openzeppelin/contracts/token/ERC721/extensions/ERC721URIStorage.sol";
import "@openzeppelin/contracts/utils/Counters.sol";
import "hardhat/console.sol";
import { Base64 } from "./libraries/Base64.sol";
contract MyEpicNFT is ERC721URIStorage {
using Counters for Counters.Counter;
Counters.Counter private _tokenIds;
string baseSvg = "<svg xmlns='http://www.w3.org/2000/svg' preserveAspectRatio='xMinYMin meet' viewBox='0 0 350 350'><style>.base { fill: white; font-family: serif; font-size: 24px; }</style><rect width='100%' height='100%' fill='black' /><text x='50%' y='50%' class='base' dominant-baseline='middle' text-anchor='middle'>";
string[3] firstWords = ["BLAH", "BLAH", "BLAH"];
string[3] secondWords = ["BLAH", "BLAH", "BLAH"];
string[3] thirdWords = ["BLAH", "BLAH", "BLAH"];
event NewEpicNFTMinted(address sender, uint256 tokenId);
constructor() ERC721 ("SquareNFT", "SQUARE") {
console.log("This is my NFT contract. Woah!");
}
function pickRandomFirstWord(uint256 tokenId) public view returns (string memory) {
uint256 rand = random(string(abi.encodePacked("FIRST_WORD", Strings.toString(tokenId))));
rand = rand % firstWords.length;
return firstWords[rand];
}
function pickRandomSecondWord(uint256 tokenId) public view returns (string memory) {
uint256 rand = random(string(abi.encodePacked("SECOND_WORD", Strings.toString(tokenId))));
rand = rand % secondWords.length;
return secondWords[rand];
}
function pickRandomThirdWord(uint256 tokenId) public view returns (string memory) {
uint256 rand = random(string(abi.encodePacked("THIRD_WORD", Strings.toString(tokenId))));
rand = rand % thirdWords.length;
return thirdWords[rand];
}
function random(string memory input) internal pure returns (uint256) {
return uint256(keccak256(abi.encodePacked(input)));
}
function makeAnEpicNFT() public {
uint256 newItemId = _tokenIds.current();
string memory first = pickRandomFirstWord(newItemId);
string memory second = pickRandomSecondWord(newItemId);
string memory third = pickRandomThirdWord(newItemId);
string memory combinedWord = string(abi.encodePacked(first, second, third));
string memory finalSvg = string(abi.encodePacked(baseSvg, combinedWord, "</text></svg>"));
// Get all the JSON metadata in place and base64 encode it.
string memory json = Base64.encode(
bytes(
string(
abi.encodePacked(
'{"name": "',
// We set the title of our NFT as the generated word.
combinedWord,
'", "description": "A highly acclaimed collection of squares.", "image": "data:image/svg+xml;base64,',
// We add data:image/svg+xml;base64 and then append our base64 encode our svg.
Base64.encode(bytes(finalSvg)),
'"}'
)
)
)
);
// Just like before, we prepend data:application/json;base64, to our data.
string memory finalTokenUri = string(
abi.encodePacked("data:application/json;base64,", json)
);
console.log("\n--------------------");
console.log(finalTokenUri);
console.log("--------------------\n");
_safeMint(msg.sender, newItemId);
_setTokenURI(newItemId, finalTokenUri);
_tokenIds.increment();
console.log("An NFT w/ ID %s has been minted to %s", newItemId, msg.sender);
emit NewEpicNFTMinted(msg.sender, newItemId);
}
}
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