// SPDX-License-Identifier: MIT
pragma solidity >=0.6.2 <0.8.0;
/**
* @dev Collection of functions related to the address type
*/
library Address {
/**
* @dev Returns true if `account` is a contract.
*
* [IMPORTANT]
* ====
* It is unsafe to assume that an address for which this function returns
* false is an externally-owned account (EOA) and not a contract.
*
* Among others, `isContract` will return false for the following
* types of addresses:
*
* - an externally-owned account
* - a contract in construction
* - an address where a contract will be created
* - an address where a contract lived, but was destroyed
* ====
*/
function isContract(address account) internal view returns (bool) {
// This method relies on extcodesize, which returns 0 for contracts in
// construction, since the code is only stored at the end of the
// constructor execution.
uint256 size;
// solhint-disable-next-line no-inline-assembly
assembly { size := extcodesize(account) }
return size > 0;
}
/**
* @dev Replacement for Solidity's `transfer`: sends `amount` wei to
* `recipient`, forwarding all available gas and reverting on errors.
*
* https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
* of certain opcodes, possibly making contracts go over the 2300 gas limit
* imposed by `transfer`, making them unable to receive funds via
* `transfer`. {sendValue} removes this limitation.
*
* https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
*
* IMPORTANT: because control is transferred to `recipient`, care must be
* taken to not create reentrancy vulnerabilities. Consider using
* {ReentrancyGuard} or the
* https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
*/
function sendValue(address payable recipient, uint256 amount) internal {
require(address(this).balance >= amount, "Address: insufficient balance");
// solhint-disable-next-line avoid-low-level-calls, avoid-call-value
(bool success, ) = recipient.call{ value: amount }("");
require(success, "Address: unable to send value, recipient may have reverted");
}
/**
* @dev Performs a Solidity function call using a low level `call`. A
* plain`call` is an unsafe replacement for a function call: use this
* function instead.
*
* If `target` reverts with a revert reason, it is bubbled up by this
* function (like regular Solidity function calls).
*
* Returns the raw returned data. To convert to the expected return value,
* use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
*
* Requirements:
*
* - `target` must be a contract.
* - calling `target` with `data` must not revert.
*
* _Available since v3.1._
*/
function functionCall(address target, bytes memory data) internal returns (bytes memory) {
return functionCall(target, data, "Address: low-level call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
* `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
return functionCallWithValue(target, data, 0, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but also transferring `value` wei to `target`.
*
* Requirements:
*
* - the calling contract must have an ETH balance of at least `value`.
* - the called Solidity function must be `payable`.
*
* _Available since v3.1._
*/
function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
}
/**
* @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
* with `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {
require(address(this).balance >= value, "Address: insufficient balance for call");
require(isContract(target), "Address: call to non-contract");
// solhint-disable-next-line avoid-low-level-calls
(bool success, bytes memory returndata) = target.call{ value: value }(data);
return _verifyCallResult(success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/
function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
return functionStaticCall(target, data, "Address: low-level static call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/
function functionStaticCall(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {
require(isContract(target), "Address: static call to non-contract");
// solhint-disable-next-line avoid-low-level-calls
(bool success, bytes memory returndata) = target.staticcall(data);
return _verifyCallResult(success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a delegate call.
*
* _Available since v3.4._
*/
function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
return functionDelegateCall(target, data, "Address: low-level delegate call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
* but performing a delegate call.
*
* _Available since v3.4._
*/
function functionDelegateCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
require(isContract(target), "Address: delegate call to non-contract");
// solhint-disable-next-line avoid-low-level-calls
(bool success, bytes memory returndata) = target.delegatecall(data);
return _verifyCallResult(success, returndata, errorMessage);
}
function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {
if (success) {
return returndata;
} else {
// Look for revert reason and bubble it up if present
if (returndata.length > 0) {
// The easiest way to bubble the revert reason is using memory via assembly
// solhint-disable-next-line no-inline-assembly
assembly {
let returndata_size := mload(returndata)
revert(add(32, returndata), returndata_size)
}
} else {
revert(errorMessage);
}
}
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.6.0;
/**
* @dev A library for working with mutable byte buffers in Solidity.
*
* Byte buffers are mutable and expandable, and provide a variety of primitives
* for writing to them. At any time you can fetch a bytes object containing the
* current contents of the buffer. The bytes object should not be stored between
* operations, as it may change due to resizing of the buffer.
*/
library BufferChainlink {
/**
* @dev Represents a mutable buffer. Buffers have a current value (buf) and
* a capacity. The capacity may be longer than the current value, in
* which case it can be extended without the need to allocate more memory.
*/
struct buffer {
bytes buf;
uint capacity;
}
/**
* @dev Initializes a buffer with an initial capacity.
* @param buf The buffer to initialize.
* @param capacity The number of bytes of space to allocate the buffer.
* @return The buffer, for chaining.
*/
function init(buffer memory buf, uint capacity) internal pure returns(buffer memory) {
if (capacity % 32 != 0) {
capacity += 32 - (capacity % 32);
}
// Allocate space for the buffer data
buf.capacity = capacity;
assembly {
let ptr := mload(0x40)
mstore(buf, ptr)
mstore(ptr, 0)
mstore(0x40, add(32, add(ptr, capacity)))
}
return buf;
}
/**
* @dev Initializes a new buffer from an existing bytes object.
* Changes to the buffer may mutate the original value.
* @param b The bytes object to initialize the buffer with.
* @return A new buffer.
*/
function fromBytes(bytes memory b) internal pure returns(buffer memory) {
buffer memory buf;
buf.buf = b;
buf.capacity = b.length;
return buf;
}
function resize(buffer memory buf, uint capacity) private pure {
bytes memory oldbuf = buf.buf;
init(buf, capacity);
append(buf, oldbuf);
}
function max(uint a, uint b) private pure returns(uint) {
if (a > b) {
return a;
}
return b;
}
/**
* @dev Sets buffer length to 0.
* @param buf The buffer to truncate.
* @return The original buffer, for chaining..
*/
function truncate(buffer memory buf) internal pure returns (buffer memory) {
assembly {
let bufptr := mload(buf)
mstore(bufptr, 0)
}
return buf;
}
/**
* @dev Writes a byte string to a buffer. Resizes if doing so would exceed
* the capacity of the buffer.
* @param buf The buffer to append to.
* @param off The start offset to write to.
* @param data The data to append.
* @param len The number of bytes to copy.
* @return The original buffer, for chaining.
*/
function write(buffer memory buf, uint off, bytes memory data, uint len) internal pure returns(buffer memory) {
require(len <= data.length);
if (off + len > buf.capacity) {
resize(buf, max(buf.capacity, len + off) * 2);
}
uint dest;
uint src;
assembly {
// Memory address of the buffer data
let bufptr := mload(buf)
// Length of existing buffer data
let buflen := mload(bufptr)
// Start address = buffer address + offset + sizeof(buffer length)
dest := add(add(bufptr, 32), off)
// Update buffer length if we're extending it
if gt(add(len, off), buflen) {
mstore(bufptr, add(len, off))
}
src := add(data, 32)
}
// Copy word-length chunks while possible
for (; len >= 32; len -= 32) {
assembly {
mstore(dest, mload(src))
}
dest += 32;
src += 32;
}
// Copy remaining bytes
uint mask = 256 ** (32 - len) - 1;
assembly {
let srcpart := and(mload(src), not(mask))
let destpart := and(mload(dest), mask)
mstore(dest, or(destpart, srcpart))
}
return buf;
}
/**
* @dev Appends a byte string to a buffer. Resizes if doing so would exceed
* the capacity of the buffer.
* @param buf The buffer to append to.
* @param data The data to append.
* @param len The number of bytes to copy.
* @return The original buffer, for chaining.
*/
function append(buffer memory buf, bytes memory data, uint len) internal pure returns (buffer memory) {
return write(buf, buf.buf.length, data, len);
}
/**
* @dev Appends a byte string to a buffer. Resizes if doing so would exceed
* the capacity of the buffer.
* @param buf The buffer to append to.
* @param data The data to append.
* @return The original buffer, for chaining.
*/
function append(buffer memory buf, bytes memory data) internal pure returns (buffer memory) {
return write(buf, buf.buf.length, data, data.length);
}
/**
* @dev Writes a byte to the buffer. Resizes if doing so would exceed the
* capacity of the buffer.
* @param buf The buffer to append to.
* @param off The offset to write the byte at.
* @param data The data to append.
* @return The original buffer, for chaining.
*/
function writeUint8(buffer memory buf, uint off, uint8 data) internal pure returns(buffer memory) {
if (off >= buf.capacity) {
resize(buf, buf.capacity * 2);
}
assembly {
// Memory address of the buffer data
let bufptr := mload(buf)
// Length of existing buffer data
let buflen := mload(bufptr)
// Address = buffer address + sizeof(buffer length) + off
let dest := add(add(bufptr, off), 32)
mstore8(dest, data)
// Update buffer length if we extended it
if eq(off, buflen) {
mstore(bufptr, add(buflen, 1))
}
}
return buf;
}
/**
* @dev Appends a byte to the buffer. Resizes if doing so would exceed the
* capacity of the buffer.
* @param buf The buffer to append to.
* @param data The data to append.
* @return The original buffer, for chaining.
*/
function appendUint8(buffer memory buf, uint8 data) internal pure returns(buffer memory) {
return writeUint8(buf, buf.buf.length, data);
}
/**
* @dev Writes up to 32 bytes to the buffer. Resizes if doing so would
* exceed the capacity of the buffer.
* @param buf The buffer to append to.
* @param off The offset to write at.
* @param data The data to append.
* @param len The number of bytes to write (left-aligned).
* @return The original buffer, for chaining.
*/
function write(buffer memory buf, uint off, bytes32 data, uint len) private pure returns(buffer memory) {
if (len + off > buf.capacity) {
resize(buf, (len + off) * 2);
}
uint mask = 256 ** len - 1;
// Right-align data
data = data >> (8 * (32 - len));
assembly {
// Memory address of the buffer data
let bufptr := mload(buf)
// Address = buffer address + sizeof(buffer length) + off + len
let dest := add(add(bufptr, off), len)
mstore(dest, or(and(mload(dest), not(mask)), data))
// Update buffer length if we extended it
if gt(add(off, len), mload(bufptr)) {
mstore(bufptr, add(off, len))
}
}
return buf;
}
/**
* @dev Writes a bytes20 to the buffer. Resizes if doing so would exceed the
* capacity of the buffer.
* @param buf The buffer to append to.
* @param off The offset to write at.
* @param data The data to append.
* @return The original buffer, for chaining.
*/
function writeBytes20(buffer memory buf, uint off, bytes20 data) internal pure returns (buffer memory) {
return write(buf, off, bytes32(data), 20);
}
/**
* @dev Appends a bytes20 to the buffer. Resizes if doing so would exceed
* the capacity of the buffer.
* @param buf The buffer to append to.
* @param data The data to append.
* @return The original buffer, for chhaining.
*/
function appendBytes20(buffer memory buf, bytes20 data) internal pure returns (buffer memory) {
return write(buf, buf.buf.length, bytes32(data), 20);
}
/**
* @dev Appends a bytes32 to the buffer. Resizes if doing so would exceed
* the capacity of the buffer.
* @param buf The buffer to append to.
* @param data The data to append.
* @return The original buffer, for chaining.
*/
function appendBytes32(buffer memory buf, bytes32 data) internal pure returns (buffer memory) {
return write(buf, buf.buf.length, data, 32);
}
/**
* @dev Writes an integer to the buffer. Resizes if doing so would exceed
* the capacity of the buffer.
* @param buf The buffer to append to.
* @param off The offset to write at.
* @param data The data to append.
* @param len The number of bytes to write (right-aligned).
* @return The original buffer, for chaining.
*/
function writeInt(buffer memory buf, uint off, uint data, uint len) private pure returns(buffer memory) {
if (len + off > buf.capacity) {
resize(buf, (len + off) * 2);
}
uint mask = 256 ** len - 1;
assembly {
// Memory address of the buffer data
let bufptr := mload(buf)
// Address = buffer address + off + sizeof(buffer length) + len
let dest := add(add(bufptr, off), len)
mstore(dest, or(and(mload(dest), not(mask)), data))
// Update buffer length if we extended it
if gt(add(off, len), mload(bufptr)) {
mstore(bufptr, add(off, len))
}
}
return buf;
}
/**
* @dev Appends a byte to the end of the buffer. Resizes if doing so would
* exceed the capacity of the buffer.
* @param buf The buffer to append to.
* @param data The data to append.
* @return The original buffer.
*/
function appendInt(buffer memory buf, uint data, uint len) internal pure returns(buffer memory) {
return writeInt(buf, buf.buf.length, data, len);
}
}
// SPDX-License-Identifier: MIT
pragma solidity >= 0.4.19 < 0.7.0;
import { BufferChainlink } from "./BufferChainlink.sol";
library CBORChainlink {
using BufferChainlink for BufferChainlink.buffer;
uint8 private constant MAJOR_TYPE_INT = 0;
uint8 private constant MAJOR_TYPE_NEGATIVE_INT = 1;
uint8 private constant MAJOR_TYPE_BYTES = 2;
uint8 private constant MAJOR_TYPE_STRING = 3;
uint8 private constant MAJOR_TYPE_ARRAY = 4;
uint8 private constant MAJOR_TYPE_MAP = 5;
uint8 private constant MAJOR_TYPE_TAG = 6;
uint8 private constant MAJOR_TYPE_CONTENT_FREE = 7;
uint8 private constant TAG_TYPE_BIGNUM = 2;
uint8 private constant TAG_TYPE_NEGATIVE_BIGNUM = 3;
function encodeType(BufferChainlink.buffer memory buf, uint8 major, uint value) private pure {
if(value <= 23) {
buf.appendUint8(uint8((major << 5) | value));
} else if(value <= 0xFF) {
buf.appendUint8(uint8((major << 5) | 24));
buf.appendInt(value, 1);
} else if(value <= 0xFFFF) {
buf.appendUint8(uint8((major << 5) | 25));
buf.appendInt(value, 2);
} else if(value <= 0xFFFFFFFF) {
buf.appendUint8(uint8((major << 5) | 26));
buf.appendInt(value, 4);
} else if(value <= 0xFFFFFFFFFFFFFFFF) {
buf.appendUint8(uint8((major << 5) | 27));
buf.appendInt(value, 8);
}
}
function encodeIndefiniteLengthType(BufferChainlink.buffer memory buf, uint8 major) private pure {
buf.appendUint8(uint8((major << 5) | 31));
}
function encodeUInt(BufferChainlink.buffer memory buf, uint value) internal pure {
encodeType(buf, MAJOR_TYPE_INT, value);
}
function encodeInt(BufferChainlink.buffer memory buf, int value) internal pure {
if(value < -0x10000000000000000) {
encodeSignedBigNum(buf, value);
} else if(value > 0xFFFFFFFFFFFFFFFF) {
encodeBigNum(buf, value);
} else if(value >= 0) {
encodeType(buf, MAJOR_TYPE_INT, uint(value));
} else {
encodeType(buf, MAJOR_TYPE_NEGATIVE_INT, uint(-1 - value));
}
}
function encodeBytes(BufferChainlink.buffer memory buf, bytes memory value) internal pure {
encodeType(buf, MAJOR_TYPE_BYTES, value.length);
buf.append(value);
}
function encodeBigNum(BufferChainlink.buffer memory buf, int value) internal pure {
buf.appendUint8(uint8((MAJOR_TYPE_TAG << 5) | TAG_TYPE_BIGNUM));
encodeBytes(buf, abi.encode(uint(value)));
}
function encodeSignedBigNum(BufferChainlink.buffer memory buf, int input) internal pure {
buf.appendUint8(uint8((MAJOR_TYPE_TAG << 5) | TAG_TYPE_NEGATIVE_BIGNUM));
encodeBytes(buf, abi.encode(uint(-1 - input)));
}
function encodeString(BufferChainlink.buffer memory buf, string memory value) internal pure {
encodeType(buf, MAJOR_TYPE_STRING, bytes(value).length);
buf.append(bytes(value));
}
function startArray(BufferChainlink.buffer memory buf) internal pure {
encodeIndefiniteLengthType(buf, MAJOR_TYPE_ARRAY);
}
function startMap(BufferChainlink.buffer memory buf) internal pure {
encodeIndefiniteLengthType(buf, MAJOR_TYPE_MAP);
}
function endSequence(BufferChainlink.buffer memory buf) internal pure {
encodeIndefiniteLengthType(buf, MAJOR_TYPE_CONTENT_FREE);
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.6.0;
import { CBORChainlink } from "./vendor/CBORChainlink.sol";
import { BufferChainlink } from "./vendor/BufferChainlink.sol";
/**
* @title Library for common Chainlink functions
* @dev Uses imported CBOR library for encoding to buffer
*/
library Chainlink {
uint256 internal constant defaultBufferSize = 256; // solhint-disable-line const-name-snakecase
using CBORChainlink for BufferChainlink.buffer;
struct Request {
bytes32 id;
address callbackAddress;
bytes4 callbackFunctionId;
uint256 nonce;
BufferChainlink.buffer buf;
}
/**
* @notice Initializes a Chainlink request
* @dev Sets the ID, callback address, and callback function signature on the request
* @param self The uninitialized request
* @param _id The Job Specification ID
* @param _callbackAddress The callback address
* @param _callbackFunction The callback function signature
* @return The initialized request
*/
function initialize(
Request memory self,
bytes32 _id,
address _callbackAddress,
bytes4 _callbackFunction
) internal pure returns (Chainlink.Request memory) {
BufferChainlink.init(self.buf, defaultBufferSize);
self.id = _id;
self.callbackAddress = _callbackAddress;
self.callbackFunctionId = _callbackFunction;
return self;
}
/**
* @notice Sets the data for the buffer without encoding CBOR on-chain
* @dev CBOR can be closed with curly-brackets {} or they can be left off
* @param self The initialized request
* @param _data The CBOR data
*/
function setBuffer(Request memory self, bytes memory _data)
internal pure
{
BufferChainlink.init(self.buf, _data.length);
BufferChainlink.append(self.buf, _data);
}
/**
* @notice Adds a string value to the request with a given key name
* @param self The initialized request
* @param _key The name of the key
* @param _value The string value to add
*/
function add(Request memory self, string memory _key, string memory _value)
internal pure
{
self.buf.encodeString(_key);
self.buf.encodeString(_value);
}
/**
* @notice Adds a bytes value to the request with a given key name
* @param self The initialized request
* @param _key The name of the key
* @param _value The bytes value to add
*/
function addBytes(Request memory self, string memory _key, bytes memory _value)
internal pure
{
self.buf.encodeString(_key);
self.buf.encodeBytes(_value);
}
/**
* @notice Adds a int256 value to the request with a given key name
* @param self The initialized request
* @param _key The name of the key
* @param _value The int256 value to add
*/
function addInt(Request memory self, string memory _key, int256 _value)
internal pure
{
self.buf.encodeString(_key);
self.buf.encodeInt(_value);
}
/**
* @notice Adds a uint256 value to the request with a given key name
* @param self The initialized request
* @param _key The name of the key
* @param _value The uint256 value to add
*/
function addUint(Request memory self, string memory _key, uint256 _value)
internal pure
{
self.buf.encodeString(_key);
self.buf.encodeUInt(_value);
}
/**
* @notice Adds an array of strings to the request with a given key name
* @param self The initialized request
* @param _key The name of the key
* @param _values The array of string values to add
*/
function addStringArray(Request memory self, string memory _key, string[] memory _values)
internal pure
{
self.buf.encodeString(_key);
self.buf.startArray();
for (uint256 i = 0; i < _values.length; i++) {
self.buf.encodeString(_values[i]);
}
self.buf.endSequence();
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.6.0;
import "./Chainlink.sol";
import "./interfaces/ENSInterface.sol";
import "./interfaces/LinkTokenInterface.sol";
import "./interfaces/ChainlinkRequestInterface.sol";
import "./interfaces/PointerInterface.sol";
import { ENSResolver as ENSResolver_Chainlink } from "./vendor/ENSResolver.sol";
/**
* @title The ChainlinkClient contract
* @notice Contract writers can inherit this contract in order to create requests for the
* Chainlink network
*/
contract ChainlinkClient {
using Chainlink for Chainlink.Request;
uint256 constant internal LINK = 10**18;
uint256 constant private AMOUNT_OVERRIDE = 0;
address constant private SENDER_OVERRIDE = address(0);
uint256 constant private ARGS_VERSION = 1;
bytes32 constant private ENS_TOKEN_SUBNAME = keccak256("link");
bytes32 constant private ENS_ORACLE_SUBNAME = keccak256("oracle");
address constant private LINK_TOKEN_POINTER = 0xC89bD4E1632D3A43CB03AAAd5262cbe4038Bc571;
ENSInterface private ens;
bytes32 private ensNode;
LinkTokenInterface private link;
ChainlinkRequestInterface private oracle;
uint256 private requestCount = 1;
mapping(bytes32 => address) private pendingRequests;
event ChainlinkRequested(bytes32 indexed id);
event ChainlinkFulfilled(bytes32 indexed id);
event ChainlinkCancelled(bytes32 indexed id);
/**
* @notice Creates a request that can hold additional parameters
* @param _specId The Job Specification ID that the request will be created for
* @param _callbackAddress The callback address that the response will be sent to
* @param _callbackFunctionSignature The callback function signature to use for the callback address
* @return A Chainlink Request struct in memory
*/
function buildChainlinkRequest(
bytes32 _specId,
address _callbackAddress,
bytes4 _callbackFunctionSignature
) internal pure returns (Chainlink.Request memory) {
Chainlink.Request memory req;
return req.initialize(_specId, _callbackAddress, _callbackFunctionSignature);
}
/**
* @notice Creates a Chainlink request to the stored oracle address
* @dev Calls `chainlinkRequestTo` with the stored oracle address
* @param _req The initialized Chainlink Request
* @param _payment The amount of LINK to send for the request
* @return requestId The request ID
*/
function sendChainlinkRequest(Chainlink.Request memory _req, uint256 _payment)
internal
returns (bytes32)
{
return sendChainlinkRequestTo(address(oracle), _req, _payment);
}
/**
* @notice Creates a Chainlink request to the specified oracle address
* @dev Generates and stores a request ID, increments the local nonce, and uses `transferAndCall` to
* send LINK which creates a request on the target oracle contract.
* Emits ChainlinkRequested event.
* @param _oracle The address of the oracle for the request
* @param _req The initialized Chainlink Request
* @param _payment The amount of LINK to send for the request
* @return requestId The request ID
*/
function sendChainlinkRequestTo(address _oracle, Chainlink.Request memory _req, uint256 _payment)
internal
returns (bytes32 requestId)
{
requestId = keccak256(abi.encodePacked(this, requestCount));
_req.nonce = requestCount;
pendingRequests[requestId] = _oracle;
emit ChainlinkRequested(requestId);
require(link.transferAndCall(_oracle, _payment, encodeRequest(_req)), "unable to transferAndCall to oracle");
requestCount += 1;
return requestId;
}
/**
* @notice Allows a request to be cancelled if it has not been fulfilled
* @dev Requires keeping track of the expiration value emitted from the oracle contract.
* Deletes the request from the `pendingRequests` mapping.
* Emits ChainlinkCancelled event.
* @param _requestId The request ID
* @param _payment The amount of LINK sent for the request
* @param _callbackFunc The callback function specified for the request
* @param _expiration The time of the expiration for the request
*/
function cancelChainlinkRequest(
bytes32 _requestId,
uint256 _payment,
bytes4 _callbackFunc,
uint256 _expiration
)
internal
{
ChainlinkRequestInterface requested = ChainlinkRequestInterface(pendingRequests[_requestId]);
delete pendingRequests[_requestId];
emit ChainlinkCancelled(_requestId);
requested.cancelOracleRequest(_requestId, _payment, _callbackFunc, _expiration);
}
/**
* @notice Sets the stored oracle address
* @param _oracle The address of the oracle contract
*/
function setChainlinkOracle(address _oracle) internal {
oracle = ChainlinkRequestInterface(_oracle);
}
/**
* @notice Sets the LINK token address
* @param _link The address of the LINK token contract
*/
function setChainlinkToken(address _link) internal {
link = LinkTokenInterface(_link);
}
/**
* @notice Sets the Chainlink token address for the public
* network as given by the Pointer contract
*/
function setPublicChainlinkToken() internal {
setChainlinkToken(PointerInterface(LINK_TOKEN_POINTER).getAddress());
}
/**
* @notice Retrieves the stored address of the LINK token
* @return The address of the LINK token
*/
function chainlinkTokenAddress()
internal
view
returns (address)
{
return address(link);
}
/**
* @notice Retrieves the stored address of the oracle contract
* @return The address of the oracle contract
*/
function chainlinkOracleAddress()
internal
view
returns (address)
{
return address(oracle);
}
/**
* @notice Allows for a request which was created on another contract to be fulfilled
* on this contract
* @param _oracle The address of the oracle contract that will fulfill the request
* @param _requestId The request ID used for the response
*/
function addChainlinkExternalRequest(address _oracle, bytes32 _requestId)
internal
notPendingRequest(_requestId)
{
pendingRequests[_requestId] = _oracle;
}
/**
* @notice Sets the stored oracle and LINK token contracts with the addresses resolved by ENS
* @dev Accounts for subnodes having different resolvers
* @param _ens The address of the ENS contract
* @param _node The ENS node hash
*/
function useChainlinkWithENS(address _ens, bytes32 _node)
internal
{
ens = ENSInterface(_ens);
ensNode = _node;
bytes32 linkSubnode = keccak256(abi.encodePacked(ensNode, ENS_TOKEN_SUBNAME));
ENSResolver_Chainlink resolver = ENSResolver_Chainlink(ens.resolver(linkSubnode));
setChainlinkToken(resolver.addr(linkSubnode));
updateChainlinkOracleWithENS();
}
/**
* @notice Sets the stored oracle contract with the address resolved by ENS
* @dev This may be called on its own as long as `useChainlinkWithENS` has been called previously
*/
function updateChainlinkOracleWithENS()
internal
{
bytes32 oracleSubnode = keccak256(abi.encodePacked(ensNode, ENS_ORACLE_SUBNAME));
ENSResolver_Chainlink resolver = ENSResolver_Chainlink(ens.resolver(oracleSubnode));
setChainlinkOracle(resolver.addr(oracleSubnode));
}
/**
* @notice Encodes the request to be sent to the oracle contract
* @dev The Chainlink node expects values to be in order for the request to be picked up. Order of types
* will be validated in the oracle contract.
* @param _req The initialized Chainlink Request
* @return The bytes payload for the `transferAndCall` method
*/
function encodeRequest(Chainlink.Request memory _req)
private
view
returns (bytes memory)
{
return abi.encodeWithSelector(
oracle.oracleRequest.selector,
SENDER_OVERRIDE, // Sender value - overridden by onTokenTransfer by the requesting contract's address
AMOUNT_OVERRIDE, // Amount value - overridden by onTokenTransfer by the actual amount of LINK sent
_req.id,
_req.callbackAddress,
_req.callbackFunctionId,
_req.nonce,
ARGS_VERSION,
_req.buf.buf);
}
/**
* @notice Ensures that the fulfillment is valid for this contract
* @dev Use if the contract developer prefers methods instead of modifiers for validation
* @param _requestId The request ID for fulfillment
*/
function validateChainlinkCallback(bytes32 _requestId)
internal
recordChainlinkFulfillment(_requestId)
// solhint-disable-next-line no-empty-blocks
{}
/**
* @dev Reverts if the sender is not the oracle of the request.
* Emits ChainlinkFulfilled event.
* @param _requestId The request ID for fulfillment
*/
modifier recordChainlinkFulfillment(bytes32 _requestId) {
require(msg.sender == pendingRequests[_requestId],
"Source must be the oracle of the request");
delete pendingRequests[_requestId];
emit ChainlinkFulfilled(_requestId);
_;
}
/**
* @dev Reverts if the request is already pending
* @param _requestId The request ID for fulfillment
*/
modifier notPendingRequest(bytes32 _requestId) {
require(pendingRequests[_requestId] == address(0), "Request is already pending");
_;
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.6.0;
interface ChainlinkRequestInterface {
function oracleRequest(
address sender,
uint256 requestPrice,
bytes32 serviceAgreementID,
address callbackAddress,
bytes4 callbackFunctionId,
uint256 nonce,
uint256 dataVersion,
bytes calldata data
) external;
function cancelOracleRequest(
bytes32 requestId,
uint256 payment,
bytes4 callbackFunctionId,
uint256 expiration
) external;
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
/*
* @dev Provides information about the current execution context, including the
* sender of the transaction and its data. While these are generally available
* via msg.sender and msg.data, they should not be accessed in such a direct
* manner, since when dealing with GSN meta-transactions the account sending and
* paying for execution may not be the actual sender (as far as an application
* is concerned).
*
* This contract is only required for intermediate, library-like contracts.
*/
abstract contract Context {
function _msgSender() internal view virtual returns (address payable) {
return msg.sender;
}
function _msgData() internal view virtual returns (bytes memory) {
this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
return msg.data;
}
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
import "../math/SafeMath.sol";
/**
* @title Counters
* @author Matt Condon (@shrugs)
* @dev Provides counters that can only be incremented or decremented by one. This can be used e.g. to track the number
* of elements in a mapping, issuing ERC721 ids, or counting request ids.
*
* Include with `using Counters for Counters.Counter;`
* Since it is not possible to overflow a 256 bit integer with increments of one, `increment` can skip the {SafeMath}
* overflow check, thereby saving gas. This does assume however correct usage, in that the underlying `_value` is never
* directly accessed.
*/
library Counters {
using SafeMath for uint256;
struct Counter {
// This variable should never be directly accessed by users of the library: interactions must be restricted to
// the library's function. As of Solidity v0.5.2, this cannot be enforced, though there is a proposal to add
// this feature: see https://github.com/ethereum/solidity/issues/4637
uint256 _value; // default: 0
}
function current(Counter storage counter) internal view returns (uint256) {
return counter._value;
}
function increment(Counter storage counter) internal {
// The {SafeMath} overflow check can be skipped here, see the comment at the top
counter._value += 1;
}
function decrement(Counter storage counter) internal {
counter._value = counter._value.sub(1);
}
}
// SPDX-License-Identifier: MIT
pragma solidity 0.6.6;
// Truffle
import "@openzeppelin/contracts/token/ERC721/ERC721.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/utils/Counters.sol";
import "@chainlink/contracts/v0.6/ChainlinkClient.sol";
// import "@chainlink/contracts/src/v0.6/VRFConsumerBase.sol";
// Modified VRFConsumerBase to not conflict with ChainlinkClient.
import "./VRFConsumerBase.sol";
// Remix
//import "https://github.com/OpenZeppelin/openzeppelin-contracts/blob/v3.4.0/contracts/token/ERC721/ERC721.sol";
//import "https://github.com/OpenZeppelin/openzeppelin-contracts/blob/v3.4.0/contracts/access/Ownable.sol";
//import "https://github.com/OpenZeppelin/openzeppelin-contracts/blob/v3.4.0/contracts/utils/Counters.sol";
//import "https://github.com/smartcontractkit/chainlink/blob/develop/evm-contracts/src/v0.6/ChainlinkClient.sol";
//import "https://github.com/smartcontractkit/chainlink/blob/develop/evm-contracts/src/v0.6/VRFConsumerBase.sol";
contract CryptoTrunks is ERC721, Ownable, ChainlinkClient, VRFConsumerBase {
using Counters for Counters.Counter;
// Pausable.
bool private _paused;
// Represents a minting user, for lookup from Chainlink fulfill.
struct User {
uint256 tokenId;
address addr;
}
// Generative
uint16 constant private generativeSupply = 19500;
Counters.Counter private generativeMinted;
// Genesis
uint16 constant private genesisSupply = 1500;
Counters.Counter private genesisMinted;
uint256 constant private genesisPrime = 22801763477; // Prime chosen at random (10 millionth)
// Chainlink internals.
address private oracle;
bytes32 private jobId;
uint256 private fee;
// Chainlink VRF constants.
bytes32 internal keyHash;
uint256 internal vrfFee;
// Returned from VRF.
uint256 private genesisRandomSeed;
// Mapping from Chainlink `requestId` to the user who triggered it.
mapping (bytes32 => User) private users;
// Mapping from address to the fee the user will pay next.
mapping (address => uint256) private nextFeeTiers;
// Mapping from address to minted count.
mapping (address => uint16) private mintedCount;
// Events
event RemoteMintFulfilled(bytes32 requestId, uint256 tokenId, uint256 resultId);
event RemoteMintTwentyFulfilled(bytes32 requestId, uint256 firstTokenId, uint256 resultId);
/**
* Constructor
*/
// TODO: Change VRFConsumerBase to mainnet .
constructor() public
ERC721("CryptoTrunks", "CT")
VRFConsumerBase(
0xf0d54349aDdcf704F77AE15b96510dEA15cb7952, // VRF Coordinator
0x514910771AF9Ca656af840dff83E8264EcF986CA // LINK Token
)
{
// Metadata setup.
_setBaseURI("https://service.cryptotrunks.co/token/");
// Chainlink setup.
setPublicChainlinkToken();
// Our node
// oracle = 0xDAca12D022D5fe11c857d6f583Bb43D01a8f5B73;
// jobId = "d562d13f83a947d4bb720be4a2682978";
// fee = 1 * 10 ** 18; // 1 * 10 ** 18 = 1 Link
// Kovan
// oracle = 0xAA1DC356dc4B18f30C347798FD5379F3D77ABC5b;
// jobId = "c7dd72ca14b44f0c9b6cfcd4b7ec0a2c";
// fee = 0.1 * 10 ** 18; // 1 * 10 ** 18 = 1 Link
// VRF setup.
// Kovan network.
// TODO: Change this to mainnet
keyHash = 0xAA77729D3466CA35AE8D28B3BBAC7CC36A5031EFDC430821C02BC31A238AF445;
vrfFee = 2 * 10 ** 18; // 1 * 10 ** 18 = 1 Link
}
/**
* Payout
*/
function withdraw() external onlyOwner {
address payable payableOwner = payable(owner());
payableOwner.transfer(address(this).balance);
}
function withdrawLink() external onlyOwner {
LinkTokenInterface link = LinkTokenInterface(chainlinkTokenAddress());
address payable payableOwner = payable(owner());
link.transfer(payableOwner, link.balanceOf(address(this)));
}
/**
* Pausing
*/
function paused() external view returns (bool) {
return _paused;
}
function togglePaused() external onlyOwner {
_paused = !_paused;
}
/**
* Updating Oracle
*/
function getOracle() external view returns (address, bytes32, uint256) {
return (oracle, jobId, fee);
}
function updateOracle(address _oracle, bytes32 _jobId, uint256 _fee) external onlyOwner {
oracle = _oracle;
jobId = _jobId;
fee = _fee;
}
/**
* Methods for Web3
*/
function getGenerativeMinted() external view returns (uint256) {
return generativeMinted.current();
}
function getGenesisMinted() external view returns (uint256) {
return genesisMinted.current();
}
function getGenesisRandomSeed() external view returns (uint256) {
return genesisRandomSeed;
}
/**
* Generative minting
*/
function mintTrunk(uint256 randomSeed, bool isBasic) external payable returns (uint256 tokenId) {
// Enforce tiered fees.
require(msg.value >= getBaseFeeTier());
require(msg.value >= getFeeTier());
// In pause, prevent "free" mints.
if (_paused) {
require(msg.value >= (0.05 ether));
}
// Update minted count.
mintedCount[msg.sender] = (mintedCount[msg.sender] + 1);
// Limit supply.
require(generativeMinted.current() < generativeSupply); // 0 ..< 19,500
generativeMinted.increment(); // Start at 1 (tokens 1 ..< 19,501)
// Get current token, starting after the last genesis trunk (i.e. 1,501).
uint256 _tokenId = genesisSupply + generativeMinted.current(); // 1,501 ..< 21,001
// Mint token itself.
_safeMint(msg.sender, _tokenId);
// In order to save Link for the most basic combination (Sapling + Noon),
// we skip remoteMint, since no-one would fake the most basic level.
if (isBasic) {
// Skip oracle step for basic trunks.
// Since we aren't storing this with the oracle, set the seed as the token URI.
completeMint(0x00, _tokenId, randomSeed);
} else {
// Generate art on remote URL.
bytes32 requestId = remoteMint(randomSeed, _tokenId);
// Store token to mapping for when request completes.
users[requestId] = User(_tokenId, msg.sender);
}
// Returned so web3 can filter on it.
return _tokenId;
}
function mintTwentyTrunks() external payable returns (uint256 tokenId) {
// Enforce tiered fees.
require(msg.value >= 1 ether);
// Limit supply.
require(generativeMinted.current() + 20 <= generativeSupply);
// First token ID, one more than current.
uint256 firstTokenId = genesisSupply + generativeMinted.current() + 1;
for (uint8 i = 0; i < 20; i++) {
// Mint token itself.
generativeMinted.increment();
_safeMint(msg.sender, (genesisSupply + generativeMinted.current()));
}
// Generate art (x20) on remote URL.
bytes32 requestId = remoteMintTwenty(firstTokenId);
// Store token to mapping for when request completes.
users[requestId] = User(firstTokenId, msg.sender);
// Returned so web3 can filter on it.
return firstTokenId;
}
function getFeeTier() public view returns (uint256 feeTier) {
// Fee tier generated from value returned from our service.
uint256 nextFeeTier = nextFeeTiers[msg.sender];
if (nextFeeTier == 0) {
return 0;
} else {
return nextFeeTier;
}
}
function getBaseFeeTier() public view returns (uint256 baseFeeTier) {
// Fallback check to guard the base price.
uint16 minted = mintedCount[msg.sender];
if (minted == 0) {
return 0;
} else {
// Multiplier is divided by 10 at the end to avoid floating point.
uint256 multiplier = 10;
if (minted < 5) {
multiplier = 10;
} else if (minted < 20) {
multiplier = 15;
} else if (minted < 50) {
multiplier = 20;
} else if (minted < 100) {
multiplier = 25;
} else {
multiplier = 30;
}
return ((0.05 ether) * multiplier) / 10;
}
}
/**
* Genesis minting
*/
function mintGenesisTrunk(uint256 numberToMint) external payable returns (uint256[] memory tokenIds) {
// Minting constraints.
require(numberToMint >= 1);
require(numberToMint <= 20);
require(numberToMint <= (genesisSupply - genesisMinted.current()));
// Ensure we collect enough eth!
require(msg.value >= (0.5 ether) * numberToMint);
// Loop minting.
uint256[] memory _tokenIds = new uint256[](numberToMint);
for (uint256 i = 0; i < numberToMint; i++) {
uint256 tokenId = mintGenesisTrunk();
_tokenIds[i] = tokenId;
}
return _tokenIds;
}
function mintGenesisTrunk() private returns (uint256 tokenId) {
// Limit supply.
require(genesisMinted.current() < genesisSupply); // 0 ..< 1,500
genesisMinted.increment(); // Start at 1 (tokens 1 ..< 1,501)
// Check we seeded the genesis random seed.
require(genesisRandomSeed != 0);
// Get current token.
// Turns 1 ..< 1,501 into a random (but unminted) number in that range.
uint256 _tokenId = getRandomGenesisTrunk(genesisMinted.current());
// Mint token itself.
_safeMint(msg.sender, _tokenId);
// Returned so web3 can filter on it.
return _tokenId;
}
// Required to be called before first mint to populate genesisRandomSeed.
function fetchGenesisSeedFromVRF() external onlyOwner {
getRandomNumber();
}
// "Shuffles" our list, from random seed, without using much storage, starting at 1.
// This works because (a x + b) modulo n visits all integers in 0..<n exactly once
// as x iterates through the integers in 0..<n, so long as a is coprime with n.
function getRandomGenesisTrunk(uint256 index) private view returns (uint256) {
return (((index * genesisPrime) + genesisRandomSeed) % genesisSupply) + 1;
}
// Updates
function setBaseURI(string calldata baseURI_) external onlyOwner {
// Allows us to update the baseURI after deploy, so we can move to IPFS if we choose to.
_setBaseURI(baseURI_);
}
/**
* Chainlink fetch
*/
// Regular
function remoteMint(uint256 randomSeed, uint256 tokenId) private returns (bytes32 requestId) {
// Make the Chainlink request.
Chainlink.Request memory request = buildChainlinkRequest(jobId, address(this), this.fulfill.selector);
string memory url = string(
abi.encodePacked(
"https://service.cryptotrunks.co/mint?address=", toString(msg.sender),
"&seed=", randomSeed.toString(),
"&token=", tokenId.toString()
)
);
request.add("get", url);
request.add("path", "result"); // jsonpath.com
return sendChainlinkRequestTo(oracle, request, fee);
}
function fulfill(bytes32 _requestId, uint256 _resultId) public recordChainlinkFulfillment(_requestId) {
require(_resultId > 0);
// Retrieve user from mapping.
User memory user = users[_requestId];
require(user.addr != address(0));
// _resultId is made up of returned token id + next minting fee.
// e.g. if token = 1234 and fee = 0.15 ether, oracle returns 1234150.
// Inlined below to save space.
// uint256 returnedFeeTier = _resultId % 1000; // Get last digits.
// uint256 returnedTokenId = _resultId / 1000; // Get other digits.
// Store tree age for future mints.
nextFeeTiers[user.addr] = ((_resultId % 1000) * 1 ether) / 1000;
completeMint(_requestId, user.tokenId, (_resultId / 1000));
}
function completeMint(bytes32 _requestId, uint256 _tokenId, uint256 _returnedTokenId) private {
// Update our token URI in case it changed.
_setTokenURI(_tokenId, _returnedTokenId.toString());
// Emit event for Web3.
emit RemoteMintFulfilled(_requestId, _tokenId, _returnedTokenId);
}
// Minting 20 ("Gamble")
function remoteMintTwenty(uint256 tokenId) private returns (bytes32 requestId) {
// Make the Chainlink request.
Chainlink.Request memory request = buildChainlinkRequest(jobId, address(this), this.fulfillTwenty.selector);
string memory url = string(
abi.encodePacked(
"https://service.cryptotrunks.co/mint_twenty?address=", toString(msg.sender),
"&token=", tokenId.toString()
)
);
request.add("get", url);
request.add("path", "result"); // jsonpath.com
return sendChainlinkRequestTo(oracle, request, fee);
}
function fulfillTwenty(bytes32 _requestId, uint256 _resultId) public recordChainlinkFulfillment(_requestId) {
require(_resultId > 0);
// Retrieve user from mapping.
User memory user = users[_requestId];
require(user.addr != address(0));
// Gambling doesn't affect fee tier.
// Since we can't afford the gas, the service will assume token ID is the baseURI,
// i.e. we're not going make 20 _setTokenURI() calls here.
// Emit event for Web3.
emit RemoteMintTwentyFulfilled(_requestId, user.tokenId, _resultId);
}
/**
* Chainlink VRF
*/
function getRandomNumber() private returns (bytes32 requestId) {
// Only permit if this has never been run.
require(genesisRandomSeed == 0);
return requestRandomness(keyHash, vrfFee, block.number);
}
function fulfillRandomness(bytes32 /* requestId */, uint256 randomness) internal override {
genesisRandomSeed = randomness;
}
/**
* Utils
*/
function toString(address account) private pure returns (string memory) {
return toString(abi.encodePacked(account));
}
// https://ethereum.stackexchange.com/a/58341/68257
function toString(bytes memory data) private pure returns (string memory) {
bytes memory alphabet = "0123456789abcdef";
bytes memory str = new bytes(2 + data.length * 2);
str[0] = "0";
str[1] = "x";
for (uint i = 0; i < data.length; i++) {
str[2+i*2] = alphabet[uint(uint8(data[i] >> 4))];
str[3+i*2] = alphabet[uint(uint8(data[i] & 0x0f))];
}
return string(str);
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.6.0;
interface ENSInterface {
// Logged when the owner of a node assigns a new owner to a subnode.
event NewOwner(bytes32 indexed node, bytes32 indexed label, address owner);
// Logged when the owner of a node transfers ownership to a new account.
event Transfer(bytes32 indexed node, address owner);
// Logged when the resolver for a node changes.
event NewResolver(bytes32 indexed node, address resolver);
// Logged when the TTL of a node changes
event NewTTL(bytes32 indexed node, uint64 ttl);
function setSubnodeOwner(bytes32 node, bytes32 label, address _owner) external;
function setResolver(bytes32 node, address _resolver) external;
function setOwner(bytes32 node, address _owner) external;
function setTTL(bytes32 node, uint64 _ttl) external;
function owner(bytes32 node) external view returns (address);
function resolver(bytes32 node) external view returns (address);
function ttl(bytes32 node) external view returns (uint64);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.6.0;
abstract contract ENSResolver {
function addr(bytes32 node) public view virtual returns (address);
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
import "./IERC165.sol";
/**
* @dev Implementation of the {IERC165} interface.
*
* Contracts may inherit from this and call {_registerInterface} to declare
* their support of an interface.
*/
abstract contract ERC165 is IERC165 {
/*
* bytes4(keccak256('supportsInterface(bytes4)')) == 0x01ffc9a7
*/
bytes4 private constant _INTERFACE_ID_ERC165 = 0x01ffc9a7;
/**
* @dev Mapping of interface ids to whether or not it's supported.
*/
mapping(bytes4 => bool) private _supportedInterfaces;
constructor () internal {
// Derived contracts need only register support for their own interfaces,
// we register support for ERC165 itself here
_registerInterface(_INTERFACE_ID_ERC165);
}
/**
* @dev See {IERC165-supportsInterface}.
*
* Time complexity O(1), guaranteed to always use less than 30 000 gas.
*/
function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
return _supportedInterfaces[interfaceId];
}
/**
* @dev Registers the contract as an implementer of the interface defined by
* `interfaceId`. Support of the actual ERC165 interface is automatic and
* registering its interface id is not required.
*
* See {IERC165-supportsInterface}.
*
* Requirements:
*
* - `interfaceId` cannot be the ERC165 invalid interface (`0xffffffff`).
*/
function _registerInterface(bytes4 interfaceId) internal virtual {
require(interfaceId != 0xffffffff, "ERC165: invalid interface id");
_supportedInterfaces[interfaceId] = true;
}
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
import "../../utils/Context.sol";
import "./IERC721.sol";
import "./IERC721Metadata.sol";
import "./IERC721Enumerable.sol";
import "./IERC721Receiver.sol";
import "../../introspection/ERC165.sol";
import "../../math/SafeMath.sol";
import "../../utils/Address.sol";
import "../../utils/EnumerableSet.sol";
import "../../utils/EnumerableMap.sol";
import "../../utils/Strings.sol";
/**
* @title ERC721 Non-Fungible Token Standard basic implementation
* @dev see https://eips.ethereum.org/EIPS/eip-721
*/
contract ERC721 is Context, ERC165, IERC721, IERC721Metadata, IERC721Enumerable {
using SafeMath for uint256;
using Address for address;
using EnumerableSet for EnumerableSet.UintSet;
using EnumerableMap for EnumerableMap.UintToAddressMap;
using Strings for uint256;
// Equals to `bytes4(keccak256("onERC721Received(address,address,uint256,bytes)"))`
// which can be also obtained as `IERC721Receiver(0).onERC721Received.selector`
bytes4 private constant _ERC721_RECEIVED = 0x150b7a02;
// Mapping from holder address to their (enumerable) set of owned tokens
mapping (address => EnumerableSet.UintSet) private _holderTokens;
// Enumerable mapping from token ids to their owners
EnumerableMap.UintToAddressMap private _tokenOwners;
// Mapping from token ID to approved address
mapping (uint256 => address) private _tokenApprovals;
// Mapping from owner to operator approvals
mapping (address => mapping (address => bool)) private _operatorApprovals;
// Token name
string private _name;
// Token symbol
string private _symbol;
// Optional mapping for token URIs
mapping (uint256 => string) private _tokenURIs;
// Base URI
string private _baseURI;
/*
* bytes4(keccak256('balanceOf(address)')) == 0x70a08231
* bytes4(keccak256('ownerOf(uint256)')) == 0x6352211e
* bytes4(keccak256('approve(address,uint256)')) == 0x095ea7b3
* bytes4(keccak256('getApproved(uint256)')) == 0x081812fc
* bytes4(keccak256('setApprovalForAll(address,bool)')) == 0xa22cb465
* bytes4(keccak256('isApprovedForAll(address,address)')) == 0xe985e9c5
* bytes4(keccak256('transferFrom(address,address,uint256)')) == 0x23b872dd
* bytes4(keccak256('safeTransferFrom(address,address,uint256)')) == 0x42842e0e
* bytes4(keccak256('safeTransferFrom(address,address,uint256,bytes)')) == 0xb88d4fde
*
* => 0x70a08231 ^ 0x6352211e ^ 0x095ea7b3 ^ 0x081812fc ^
* 0xa22cb465 ^ 0xe985e9c5 ^ 0x23b872dd ^ 0x42842e0e ^ 0xb88d4fde == 0x80ac58cd
*/
bytes4 private constant _INTERFACE_ID_ERC721 = 0x80ac58cd;
/*
* bytes4(keccak256('name()')) == 0x06fdde03
* bytes4(keccak256('symbol()')) == 0x95d89b41
* bytes4(keccak256('tokenURI(uint256)')) == 0xc87b56dd
*
* => 0x06fdde03 ^ 0x95d89b41 ^ 0xc87b56dd == 0x5b5e139f
*/
bytes4 private constant _INTERFACE_ID_ERC721_METADATA = 0x5b5e139f;
/*
* bytes4(keccak256('totalSupply()')) == 0x18160ddd
* bytes4(keccak256('tokenOfOwnerByIndex(address,uint256)')) == 0x2f745c59
* bytes4(keccak256('tokenByIndex(uint256)')) == 0x4f6ccce7
*
* => 0x18160ddd ^ 0x2f745c59 ^ 0x4f6ccce7 == 0x780e9d63
*/
bytes4 private constant _INTERFACE_ID_ERC721_ENUMERABLE = 0x780e9d63;
/**
* @dev Initializes the contract by setting a `name` and a `symbol` to the token collection.
*/
constructor (string memory name_, string memory symbol_) public {
_name = name_;
_symbol = symbol_;
// register the supported interfaces to conform to ERC721 via ERC165
_registerInterface(_INTERFACE_ID_ERC721);
_registerInterface(_INTERFACE_ID_ERC721_METADATA);
_registerInterface(_INTERFACE_ID_ERC721_ENUMERABLE);
}
/**
* @dev See {IERC721-balanceOf}.
*/
function balanceOf(address owner) public view virtual override returns (uint256) {
require(owner != address(0), "ERC721: balance query for the zero address");
return _holderTokens[owner].length();
}
/**
* @dev See {IERC721-ownerOf}.
*/
function ownerOf(uint256 tokenId) public view virtual override returns (address) {
return _tokenOwners.get(tokenId, "ERC721: owner query for nonexistent token");
}
/**
* @dev See {IERC721Metadata-name}.
*/
function name() public view virtual override returns (string memory) {
return _name;
}
/**
* @dev See {IERC721Metadata-symbol}.
*/
function symbol() public view virtual override returns (string memory) {
return _symbol;
}
/**
* @dev See {IERC721Metadata-tokenURI}.
*/
function tokenURI(uint256 tokenId) public view virtual override returns (string memory) {
require(_exists(tokenId), "ERC721Metadata: URI query for nonexistent token");
string memory _tokenURI = _tokenURIs[tokenId];
string memory base = baseURI();
// If there is no base URI, return the token URI.
if (bytes(base).length == 0) {
return _tokenURI;
}
// If both are set, concatenate the baseURI and tokenURI (via abi.encodePacked).
if (bytes(_tokenURI).length > 0) {
return string(abi.encodePacked(base, _tokenURI));
}
// If there is a baseURI but no tokenURI, concatenate the tokenID to the baseURI.
return string(abi.encodePacked(base, tokenId.toString()));
}
/**
* @dev Returns the base URI set via {_setBaseURI}. This will be
* automatically added as a prefix in {tokenURI} to each token's URI, or
* to the token ID if no specific URI is set for that token ID.
*/
function baseURI() public view virtual returns (string memory) {
return _baseURI;
}
/**
* @dev See {IERC721Enumerable-tokenOfOwnerByIndex}.
*/
function tokenOfOwnerByIndex(address owner, uint256 index) public view virtual override returns (uint256) {
return _holderTokens[owner].at(index);
}
/**
* @dev See {IERC721Enumerable-totalSupply}.
*/
function totalSupply() public view virtual override returns (uint256) {
// _tokenOwners are indexed by tokenIds, so .length() returns the number of tokenIds
return _tokenOwners.length();
}
/**
* @dev See {IERC721Enumerable-tokenByIndex}.
*/
function tokenByIndex(uint256 index) public view virtual override returns (uint256) {
(uint256 tokenId, ) = _tokenOwners.at(index);
return tokenId;
}
/**
* @dev See {IERC721-approve}.
*/
function approve(address to, uint256 tokenId) public virtual override {
address owner = ERC721.ownerOf(tokenId);
require(to != owner, "ERC721: approval to current owner");
require(_msgSender() == owner || ERC721.isApprovedForAll(owner, _msgSender()),
"ERC721: approve caller is not owner nor approved for all"
);
_approve(to, tokenId);
}
/**
* @dev See {IERC721-getApproved}.
*/
function getApproved(uint256 tokenId) public view virtual override returns (address) {
require(_exists(tokenId), "ERC721: approved query for nonexistent token");
return _tokenApprovals[tokenId];
}
/**
* @dev See {IERC721-setApprovalForAll}.
*/
function setApprovalForAll(address operator, bool approved) public virtual override {
require(operator != _msgSender(), "ERC721: approve to caller");
_operatorApprovals[_msgSender()][operator] = approved;
emit ApprovalForAll(_msgSender(), operator, approved);
}
/**
* @dev See {IERC721-isApprovedForAll}.
*/
function isApprovedForAll(address owner, address operator) public view virtual override returns (bool) {
return _operatorApprovals[owner][operator];
}
/**
* @dev See {IERC721-transferFrom}.
*/
function transferFrom(address from, address to, uint256 tokenId) public virtual override {
//solhint-disable-next-line max-line-length
require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: transfer caller is not owner nor approved");
_transfer(from, to, tokenId);
}
/**
* @dev See {IERC721-safeTransferFrom}.
*/
function safeTransferFrom(address from, address to, uint256 tokenId) public virtual override {
safeTransferFrom(from, to, tokenId, "");
}
/**
* @dev See {IERC721-safeTransferFrom}.
*/
function safeTransferFrom(address from, address to, uint256 tokenId, bytes memory _data) public virtual override {
require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: transfer caller is not owner nor approved");
_safeTransfer(from, to, tokenId, _data);
}
/**
* @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients
* are aware of the ERC721 protocol to prevent tokens from being forever locked.
*
* `_data` is additional data, it has no specified format and it is sent in call to `to`.
*
* This internal function is equivalent to {safeTransferFrom}, and can be used to e.g.
* implement alternative mechanisms to perform token transfer, such as signature-based.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `tokenId` token must exist and be owned by `from`.
* - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
*
* Emits a {Transfer} event.
*/
function _safeTransfer(address from, address to, uint256 tokenId, bytes memory _data) internal virtual {
_transfer(from, to, tokenId);
require(_checkOnERC721Received(from, to, tokenId, _data), "ERC721: transfer to non ERC721Receiver implementer");
}
/**
* @dev Returns whether `tokenId` exists.
*
* Tokens can be managed by their owner or approved accounts via {approve} or {setApprovalForAll}.
*
* Tokens start existing when they are minted (`_mint`),
* and stop existing when they are burned (`_burn`).
*/
function _exists(uint256 tokenId) internal view virtual returns (bool) {
return _tokenOwners.contains(tokenId);
}
/**
* @dev Returns whether `spender` is allowed to manage `tokenId`.
*
* Requirements:
*
* - `tokenId` must exist.
*/
function _isApprovedOrOwner(address spender, uint256 tokenId) internal view virtual returns (bool) {
require(_exists(tokenId), "ERC721: operator query for nonexistent token");
address owner = ERC721.ownerOf(tokenId);
return (spender == owner || getApproved(tokenId) == spender || ERC721.isApprovedForAll(owner, spender));
}
/**
* @dev Safely mints `tokenId` and transfers it to `to`.
*
* Requirements:
d*
* - `tokenId` must not exist.
* - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
*
* Emits a {Transfer} event.
*/
function _safeMint(address to, uint256 tokenId) internal virtual {
_safeMint(to, tokenId, "");
}
/**
* @dev Same as {xref-ERC721-_safeMint-address-uint256-}[`_safeMint`], with an additional `data` parameter which is
* forwarded in {IERC721Receiver-onERC721Received} to contract recipients.
*/
function _safeMint(address to, uint256 tokenId, bytes memory _data) internal virtual {
_mint(to, tokenId);
require(_checkOnERC721Received(address(0), to, tokenId, _data), "ERC721: transfer to non ERC721Receiver implementer");
}
/**
* @dev Mints `tokenId` and transfers it to `to`.
*
* WARNING: Usage of this method is discouraged, use {_safeMint} whenever possible
*
* Requirements:
*
* - `tokenId` must not exist.
* - `to` cannot be the zero address.
*
* Emits a {Transfer} event.
*/
function _mint(address to, uint256 tokenId) internal virtual {
require(to != address(0), "ERC721: mint to the zero address");
require(!_exists(tokenId), "ERC721: token already minted");
_beforeTokenTransfer(address(0), to, tokenId);
_holderTokens[to].add(tokenId);
_tokenOwners.set(tokenId, to);
emit Transfer(address(0), to, tokenId);
}
/**
* @dev Destroys `tokenId`.
* The approval is cleared when the token is burned.
*
* Requirements:
*
* - `tokenId` must exist.
*
* Emits a {Transfer} event.
*/
function _burn(uint256 tokenId) internal virtual {
address owner = ERC721.ownerOf(tokenId); // internal owner
_beforeTokenTransfer(owner, address(0), tokenId);
// Clear approvals
_approve(address(0), tokenId);
// Clear metadata (if any)
if (bytes(_tokenURIs[tokenId]).length != 0) {
delete _tokenURIs[tokenId];
}
_holderTokens[owner].remove(tokenId);
_tokenOwners.remove(tokenId);
emit Transfer(owner, address(0), tokenId);
}
/**
* @dev Transfers `tokenId` from `from` to `to`.
* As opposed to {transferFrom}, this imposes no restrictions on msg.sender.
*
* Requirements:
*
* - `to` cannot be the zero address.
* - `tokenId` token must be owned by `from`.
*
* Emits a {Transfer} event.
*/
function _transfer(address from, address to, uint256 tokenId) internal virtual {
require(ERC721.ownerOf(tokenId) == from, "ERC721: transfer of token that is not own"); // internal owner
require(to != address(0), "ERC721: transfer to the zero address");
_beforeTokenTransfer(from, to, tokenId);
// Clear approvals from the previous owner
_approve(address(0), tokenId);
_holderTokens[from].remove(tokenId);
_holderTokens[to].add(tokenId);
_tokenOwners.set(tokenId, to);
emit Transfer(from, to, tokenId);
}
/**
* @dev Sets `_tokenURI` as the tokenURI of `tokenId`.
*
* Requirements:
*
* - `tokenId` must exist.
*/
function _setTokenURI(uint256 tokenId, string memory _tokenURI) internal virtual {
require(_exists(tokenId), "ERC721Metadata: URI set of nonexistent token");
_tokenURIs[tokenId] = _tokenURI;
}
/**
* @dev Internal function to set the base URI for all token IDs. It is
* automatically added as a prefix to the value returned in {tokenURI},
* or to the token ID if {tokenURI} is empty.
*/
function _setBaseURI(string memory baseURI_) internal virtual {
_baseURI = baseURI_;
}
/**
* @dev Internal function to invoke {IERC721Receiver-onERC721Received} on a target address.
* The call is not executed if the target address is not a contract.
*
* @param from address representing the previous owner of the given token ID
* @param to target address that will receive the tokens
* @param tokenId uint256 ID of the token to be transferred
* @param _data bytes optional data to send along with the call
* @return bool whether the call correctly returned the expected magic value
*/
function _checkOnERC721Received(address from, address to, uint256 tokenId, bytes memory _data)
private returns (bool)
{
if (!to.isContract()) {
return true;
}
bytes memory returndata = to.functionCall(abi.encodeWithSelector(
IERC721Receiver(to).onERC721Received.selector,
_msgSender(),
from,
tokenId,
_data
), "ERC721: transfer to non ERC721Receiver implementer");
bytes4 retval = abi.decode(returndata, (bytes4));
return (retval == _ERC721_RECEIVED);
}
/**
* @dev Approve `to` to operate on `tokenId`
*
* Emits an {Approval} event.
*/
function _approve(address to, uint256 tokenId) internal virtual {
_tokenApprovals[tokenId] = to;
emit Approval(ERC721.ownerOf(tokenId), to, tokenId); // internal owner
}
/**
* @dev Hook that is called before any token transfer. This includes minting
* and burning.
*
* Calling conditions:
*
* - When `from` and `to` are both non-zero, ``from``'s `tokenId` will be
* transferred to `to`.
* - When `from` is zero, `tokenId` will be minted for `to`.
* - When `to` is zero, ``from``'s `tokenId` will be burned.
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
*
* To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
*/
function _beforeTokenTransfer(address from, address to, uint256 tokenId) internal virtual { }
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
/**
* @dev Library for managing an enumerable variant of Solidity's
* https://solidity.readthedocs.io/en/latest/types.html#mapping-types[`mapping`]
* type.
*
* Maps have the following properties:
*
* - Entries are added, removed, and checked for existence in constant time
* (O(1)).
* - Entries are enumerated in O(n). No guarantees are made on the ordering.
*
* ```
* contract Example {
* // Add the library methods
* using EnumerableMap for EnumerableMap.UintToAddressMap;
*
* // Declare a set state variable
* EnumerableMap.UintToAddressMap private myMap;
* }
* ```
*
* As of v3.0.0, only maps of type `uint256 -> address` (`UintToAddressMap`) are
* supported.
*/
library EnumerableMap {
// To implement this library for multiple types with as little code
// repetition as possible, we write it in terms of a generic Map type with
// bytes32 keys and values.
// The Map implementation uses private functions, and user-facing
// implementations (such as Uint256ToAddressMap) are just wrappers around
// the underlying Map.
// This means that we can only create new EnumerableMaps for types that fit
// in bytes32.
struct MapEntry {
bytes32 _key;
bytes32 _value;
}
struct Map {
// Storage of map keys and values
MapEntry[] _entries;
// Position of the entry defined by a key in the `entries` array, plus 1
// because index 0 means a key is not in the map.
mapping (bytes32 => uint256) _indexes;
}
/**
* @dev Adds a key-value pair to a map, or updates the value for an existing
* key. O(1).
*
* Returns true if the key was added to the map, that is if it was not
* already present.
*/
function _set(Map storage map, bytes32 key, bytes32 value) private returns (bool) {
// We read and store the key's index to prevent multiple reads from the same storage slot
uint256 keyIndex = map._indexes[key];
if (keyIndex == 0) { // Equivalent to !contains(map, key)
map._entries.push(MapEntry({ _key: key, _value: value }));
// The entry is stored at length-1, but we add 1 to all indexes
// and use 0 as a sentinel value
map._indexes[key] = map._entries.length;
return true;
} else {
map._entries[keyIndex - 1]._value = value;
return false;
}
}
/**
* @dev Removes a key-value pair from a map. O(1).
*
* Returns true if the key was removed from the map, that is if it was present.
*/
function _remove(Map storage map, bytes32 key) private returns (bool) {
// We read and store the key's index to prevent multiple reads from the same storage slot
uint256 keyIndex = map._indexes[key];
if (keyIndex != 0) { // Equivalent to contains(map, key)
// To delete a key-value pair from the _entries array in O(1), we swap the entry to delete with the last one
// in the array, and then remove the last entry (sometimes called as 'swap and pop').
// This modifies the order of the array, as noted in {at}.
uint256 toDeleteIndex = keyIndex - 1;
uint256 lastIndex = map._entries.length - 1;
// When the entry to delete is the last one, the swap operation is unnecessary. However, since this occurs
// so rarely, we still do the swap anyway to avoid the gas cost of adding an 'if' statement.
MapEntry storage lastEntry = map._entries[lastIndex];
// Move the last entry to the index where the entry to delete is
map._entries[toDeleteIndex] = lastEntry;
// Update the index for the moved entry
map._indexes[lastEntry._key] = toDeleteIndex + 1; // All indexes are 1-based
// Delete the slot where the moved entry was stored
map._entries.pop();
// Delete the index for the deleted slot
delete map._indexes[key];
return true;
} else {
return false;
}
}
/**
* @dev Returns true if the key is in the map. O(1).
*/
function _contains(Map storage map, bytes32 key) private view returns (bool) {
return map._indexes[key] != 0;
}
/**
* @dev Returns the number of key-value pairs in the map. O(1).
*/
function _length(Map storage map) private view returns (uint256) {
return map._entries.length;
}
/**
* @dev Returns the key-value pair stored at position `index` in the map. O(1).
*
* Note that there are no guarantees on the ordering of entries inside the
* array, and it may change when more entries are added or removed.
*
* Requirements:
*
* - `index` must be strictly less than {length}.
*/
function _at(Map storage map, uint256 index) private view returns (bytes32, bytes32) {
require(map._entries.length > index, "EnumerableMap: index out of bounds");
MapEntry storage entry = map._entries[index];
return (entry._key, entry._value);
}
/**
* @dev Tries to returns the value associated with `key`. O(1).
* Does not revert if `key` is not in the map.
*/
function _tryGet(Map storage map, bytes32 key) private view returns (bool, bytes32) {
uint256 keyIndex = map._indexes[key];
if (keyIndex == 0) return (false, 0); // Equivalent to contains(map, key)
return (true, map._entries[keyIndex - 1]._value); // All indexes are 1-based
}
/**
* @dev Returns the value associated with `key`. O(1).
*
* Requirements:
*
* - `key` must be in the map.
*/
function _get(Map storage map, bytes32 key) private view returns (bytes32) {
uint256 keyIndex = map._indexes[key];
require(keyIndex != 0, "EnumerableMap: nonexistent key"); // Equivalent to contains(map, key)
return map._entries[keyIndex - 1]._value; // All indexes are 1-based
}
/**
* @dev Same as {_get}, with a custom error message when `key` is not in the map.
*
* CAUTION: This function is deprecated because it requires allocating memory for the error
* message unnecessarily. For custom revert reasons use {_tryGet}.
*/
function _get(Map storage map, bytes32 key, string memory errorMessage) private view returns (bytes32) {
uint256 keyIndex = map._indexes[key];
require(keyIndex != 0, errorMessage); // Equivalent to contains(map, key)
return map._entries[keyIndex - 1]._value; // All indexes are 1-based
}
// UintToAddressMap
struct UintToAddressMap {
Map _inner;
}
/**
* @dev Adds a key-value pair to a map, or updates the value for an existing
* key. O(1).
*
* Returns true if the key was added to the map, that is if it was not
* already present.
*/
function set(UintToAddressMap storage map, uint256 key, address value) internal returns (bool) {
return _set(map._inner, bytes32(key), bytes32(uint256(uint160(value))));
}
/**
* @dev Removes a value from a set. O(1).
*
* Returns true if the key was removed from the map, that is if it was present.
*/
function remove(UintToAddressMap storage map, uint256 key) internal returns (bool) {
return _remove(map._inner, bytes32(key));
}
/**
* @dev Returns true if the key is in the map. O(1).
*/
function contains(UintToAddressMap storage map, uint256 key) internal view returns (bool) {
return _contains(map._inner, bytes32(key));
}
/**
* @dev Returns the number of elements in the map. O(1).
*/
function length(UintToAddressMap storage map) internal view returns (uint256) {
return _length(map._inner);
}
/**
* @dev Returns the element stored at position `index` in the set. O(1).
* Note that there are no guarantees on the ordering of values inside the
* array, and it may change when more values are added or removed.
*
* Requirements:
*
* - `index` must be strictly less than {length}.
*/
function at(UintToAddressMap storage map, uint256 index) internal view returns (uint256, address) {
(bytes32 key, bytes32 value) = _at(map._inner, index);
return (uint256(key), address(uint160(uint256(value))));
}
/**
* @dev Tries to returns the value associated with `key`. O(1).
* Does not revert if `key` is not in the map.
*
* _Available since v3.4._
*/
function tryGet(UintToAddressMap storage map, uint256 key) internal view returns (bool, address) {
(bool success, bytes32 value) = _tryGet(map._inner, bytes32(key));
return (success, address(uint160(uint256(value))));
}
/**
* @dev Returns the value associated with `key`. O(1).
*
* Requirements:
*
* - `key` must be in the map.
*/
function get(UintToAddressMap storage map, uint256 key) internal view returns (address) {
return address(uint160(uint256(_get(map._inner, bytes32(key)))));
}
/**
* @dev Same as {get}, with a custom error message when `key` is not in the map.
*
* CAUTION: This function is deprecated because it requires allocating memory for the error
* message unnecessarily. For custom revert reasons use {tryGet}.
*/
function get(UintToAddressMap storage map, uint256 key, string memory errorMessage) internal view returns (address) {
return address(uint160(uint256(_get(map._inner, bytes32(key), errorMessage))));
}
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
/**
* @dev Library for managing
* https://en.wikipedia.org/wiki/Set_(abstract_data_type)[sets] of primitive
* types.
*
* Sets have the following properties:
*
* - Elements are added, removed, and checked for existence in constant time
* (O(1)).
* - Elements are enumerated in O(n). No guarantees are made on the ordering.
*
* ```
* contract Example {
* // Add the library methods
* using EnumerableSet for EnumerableSet.AddressSet;
*
* // Declare a set state variable
* EnumerableSet.AddressSet private mySet;
* }
* ```
*
* As of v3.3.0, sets of type `bytes32` (`Bytes32Set`), `address` (`AddressSet`)
* and `uint256` (`UintSet`) are supported.
*/
library EnumerableSet {
// To implement this library for multiple types with as little code
// repetition as possible, we write it in terms of a generic Set type with
// bytes32 values.
// The Set implementation uses private functions, and user-facing
// implementations (such as AddressSet) are just wrappers around the
// underlying Set.
// This means that we can only create new EnumerableSets for types that fit
// in bytes32.
struct Set {
// Storage of set values
bytes32[] _values;
// Position of the value in the `values` array, plus 1 because index 0
// means a value is not in the set.
mapping (bytes32 => uint256) _indexes;
}
/**
* @dev Add a value to a set. O(1).
*
* Returns true if the value was added to the set, that is if it was not
* already present.
*/
function _add(Set storage set, bytes32 value) private returns (bool) {
if (!_contains(set, value)) {
set._values.push(value);
// The value is stored at length-1, but we add 1 to all indexes
// and use 0 as a sentinel value
set._indexes[value] = set._values.length;
return true;
} else {
return false;
}
}
/**
* @dev Removes a value from a set. O(1).
*
* Returns true if the value was removed from the set, that is if it was
* present.
*/
function _remove(Set storage set, bytes32 value) private returns (bool) {
// We read and store the value's index to prevent multiple reads from the same storage slot
uint256 valueIndex = set._indexes[value];
if (valueIndex != 0) { // Equivalent to contains(set, value)
// To delete an element from the _values array in O(1), we swap the element to delete with the last one in
// the array, and then remove the last element (sometimes called as 'swap and pop').
// This modifies the order of the array, as noted in {at}.
uint256 toDeleteIndex = valueIndex - 1;
uint256 lastIndex = set._values.length - 1;
// When the value to delete is the last one, the swap operation is unnecessary. However, since this occurs
// so rarely, we still do the swap anyway to avoid the gas cost of adding an 'if' statement.
bytes32 lastvalue = set._values[lastIndex];
// Move the last value to the index where the value to delete is
set._values[toDeleteIndex] = lastvalue;
// Update the index for the moved value
set._indexes[lastvalue] = toDeleteIndex + 1; // All indexes are 1-based
// Delete the slot where the moved value was stored
set._values.pop();
// Delete the index for the deleted slot
delete set._indexes[value];
return true;
} else {
return false;
}
}
/**
* @dev Returns true if the value is in the set. O(1).
*/
function _contains(Set storage set, bytes32 value) private view returns (bool) {
return set._indexes[value] != 0;
}
/**
* @dev Returns the number of values on the set. O(1).
*/
function _length(Set storage set) private view returns (uint256) {
return set._values.length;
}
/**
* @dev Returns the value stored at position `index` in the set. O(1).
*
* Note that there are no guarantees on the ordering of values inside the
* array, and it may change when more values are added or removed.
*
* Requirements:
*
* - `index` must be strictly less than {length}.
*/
function _at(Set storage set, uint256 index) private view returns (bytes32) {
require(set._values.length > index, "EnumerableSet: index out of bounds");
return set._values[index];
}
// Bytes32Set
struct Bytes32Set {
Set _inner;
}
/**
* @dev Add a value to a set. O(1).
*
* Returns true if the value was added to the set, that is if it was not
* already present.
*/
function add(Bytes32Set storage set, bytes32 value) internal returns (bool) {
return _add(set._inner, value);
}
/**
* @dev Removes a value from a set. O(1).
*
* Returns true if the value was removed from the set, that is if it was
* present.
*/
function remove(Bytes32Set storage set, bytes32 value) internal returns (bool) {
return _remove(set._inner, value);
}
/**
* @dev Returns true if the value is in the set. O(1).
*/
function contains(Bytes32Set storage set, bytes32 value) internal view returns (bool) {
return _contains(set._inner, value);
}
/**
* @dev Returns the number of values in the set. O(1).
*/
function length(Bytes32Set storage set) internal view returns (uint256) {
return _length(set._inner);
}
/**
* @dev Returns the value stored at position `index` in the set. O(1).
*
* Note that there are no guarantees on the ordering of values inside the
* array, and it may change when more values are added or removed.
*
* Requirements:
*
* - `index` must be strictly less than {length}.
*/
function at(Bytes32Set storage set, uint256 index) internal view returns (bytes32) {
return _at(set._inner, index);
}
// AddressSet
struct AddressSet {
Set _inner;
}
/**
* @dev Add a value to a set. O(1).
*
* Returns true if the value was added to the set, that is if it was not
* already present.
*/
function add(AddressSet storage set, address value) internal returns (bool) {
return _add(set._inner, bytes32(uint256(uint160(value))));
}
/**
* @dev Removes a value from a set. O(1).
*
* Returns true if the value was removed from the set, that is if it was
* present.
*/
function remove(AddressSet storage set, address value) internal returns (bool) {
return _remove(set._inner, bytes32(uint256(uint160(value))));
}
/**
* @dev Returns true if the value is in the set. O(1).
*/
function contains(AddressSet storage set, address value) internal view returns (bool) {
return _contains(set._inner, bytes32(uint256(uint160(value))));
}
/**
* @dev Returns the number of values in the set. O(1).
*/
function length(AddressSet storage set) internal view returns (uint256) {
return _length(set._inner);
}
/**
* @dev Returns the value stored at position `index` in the set. O(1).
*
* Note that there are no guarantees on the ordering of values inside the
* array, and it may change when more values are added or removed.
*
* Requirements:
*
* - `index` must be strictly less than {length}.
*/
function at(AddressSet storage set, uint256 index) internal view returns (address) {
return address(uint160(uint256(_at(set._inner, index))));
}
// UintSet
struct UintSet {
Set _inner;
}
/**
* @dev Add a value to a set. O(1).
*
* Returns true if the value was added to the set, that is if it was not
* already present.
*/
function add(UintSet storage set, uint256 value) internal returns (bool) {
return _add(set._inner, bytes32(value));
}
/**
* @dev Removes a value from a set. O(1).
*
* Returns true if the value was removed from the set, that is if it was
* present.
*/
function remove(UintSet storage set, uint256 value) internal returns (bool) {
return _remove(set._inner, bytes32(value));
}
/**
* @dev Returns true if the value is in the set. O(1).
*/
function contains(UintSet storage set, uint256 value) internal view returns (bool) {
return _contains(set._inner, bytes32(value));
}
/**
* @dev Returns the number of values on the set. O(1).
*/
function length(UintSet storage set) internal view returns (uint256) {
return _length(set._inner);
}
/**
* @dev Returns the value stored at position `index` in the set. O(1).
*
* Note that there are no guarantees on the ordering of values inside the
* array, and it may change when more values are added or removed.
*
* Requirements:
*
* - `index` must be strictly less than {length}.
*/
function at(UintSet storage set, uint256 index) internal view returns (uint256) {
return uint256(_at(set._inner, index));
}
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
/**
* @dev Interface of the ERC165 standard, as defined in the
* https://eips.ethereum.org/EIPS/eip-165[EIP].
*
* Implementers can declare support of contract interfaces, which can then be
* queried by others ({ERC165Checker}).
*
* For an implementation, see {ERC165}.
*/
interface IERC165 {
/**
* @dev Returns true if this contract implements the interface defined by
* `interfaceId`. See the corresponding
* https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
* to learn more about how these ids are created.
*
* This function call must use less than 30 000 gas.
*/
function supportsInterface(bytes4 interfaceId) external view returns (bool);
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.2 <0.8.0;
import "../../introspection/IERC165.sol";
/**
* @dev Required interface of an ERC721 compliant contract.
*/
interface IERC721 is IERC165 {
/**
* @dev Emitted when `tokenId` token is transferred from `from` to `to`.
*/
event Transfer(address indexed from, address indexed to, uint256 indexed tokenId);
/**
* @dev Emitted when `owner` enables `approved` to manage the `tokenId` token.
*/
event Approval(address indexed owner, address indexed approved, uint256 indexed tokenId);
/**
* @dev Emitted when `owner` enables or disables (`approved`) `operator` to manage all of its assets.
*/
event ApprovalForAll(address indexed owner, address indexed operator, bool approved);
/**
* @dev Returns the number of tokens in ``owner``'s account.
*/
function balanceOf(address owner) external view returns (uint256 balance);
/**
* @dev Returns the owner of the `tokenId` token.
*
* Requirements:
*
* - `tokenId` must exist.
*/
function ownerOf(uint256 tokenId) external view returns (address owner);
/**
* @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients
* are aware of the ERC721 protocol to prevent tokens from being forever locked.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `tokenId` token must exist and be owned by `from`.
* - If the caller is not `from`, it must be have been allowed to move this token by either {approve} or {setApprovalForAll}.
* - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
*
* Emits a {Transfer} event.
*/
function safeTransferFrom(address from, address to, uint256 tokenId) external;
/**
* @dev Transfers `tokenId` token from `from` to `to`.
*
* WARNING: Usage of this method is discouraged, use {safeTransferFrom} whenever possible.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `tokenId` token must be owned by `from`.
* - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
*
* Emits a {Transfer} event.
*/
function transferFrom(address from, address to, uint256 tokenId) external;
/**
* @dev Gives permission to `to` to transfer `tokenId` token to another account.
* The approval is cleared when the token is transferred.
*
* Only a single account can be approved at a time, so approving the zero address clears previous approvals.
*
* Requirements:
*
* - The caller must own the token or be an approved operator.
* - `tokenId` must exist.
*
* Emits an {Approval} event.
*/
function approve(address to, uint256 tokenId) external;
/**
* @dev Returns the account approved for `tokenId` token.
*
* Requirements:
*
* - `tokenId` must exist.
*/
function getApproved(uint256 tokenId) external view returns (address operator);
/**
* @dev Approve or remove `operator` as an operator for the caller.
* Operators can call {transferFrom} or {safeTransferFrom} for any token owned by the caller.
*
* Requirements:
*
* - The `operator` cannot be the caller.
*
* Emits an {ApprovalForAll} event.
*/
function setApprovalForAll(address operator, bool _approved) external;
/**
* @dev Returns if the `operator` is allowed to manage all of the assets of `owner`.
*
* See {setApprovalForAll}
*/
function isApprovedForAll(address owner, address operator) external view returns (bool);
/**
* @dev Safely transfers `tokenId` token from `from` to `to`.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `tokenId` token must exist and be owned by `from`.
* - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
* - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
*
* Emits a {Transfer} event.
*/
function safeTransferFrom(address from, address to, uint256 tokenId, bytes calldata data) external;
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.2 <0.8.0;
import "./IERC721.sol";
/**
* @title ERC-721 Non-Fungible Token Standard, optional enumeration extension
* @dev See https://eips.ethereum.org/EIPS/eip-721
*/
interface IERC721Enumerable is IERC721 {
/**
* @dev Returns the total amount of tokens stored by the contract.
*/
function totalSupply() external view returns (uint256);
/**
* @dev Returns a token ID owned by `owner` at a given `index` of its token list.
* Use along with {balanceOf} to enumerate all of ``owner``'s tokens.
*/
function tokenOfOwnerByIndex(address owner, uint256 index) external view returns (uint256 tokenId);
/**
* @dev Returns a token ID at a given `index` of all the tokens stored by the contract.
* Use along with {totalSupply} to enumerate all tokens.
*/
function tokenByIndex(uint256 index) external view returns (uint256);
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.2 <0.8.0;
import "./IERC721.sol";
/**
* @title ERC-721 Non-Fungible Token Standard, optional metadata extension
* @dev See https://eips.ethereum.org/EIPS/eip-721
*/
interface IERC721Metadata is IERC721 {
/**
* @dev Returns the token collection name.
*/
function name() external view returns (string memory);
/**
* @dev Returns the token collection symbol.
*/
function symbol() external view returns (string memory);
/**
* @dev Returns the Uniform Resource Identifier (URI) for `tokenId` token.
*/
function tokenURI(uint256 tokenId) external view returns (string memory);
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
/**
* @title ERC721 token receiver interface
* @dev Interface for any contract that wants to support safeTransfers
* from ERC721 asset contracts.
*/
interface IERC721Receiver {
/**
* @dev Whenever an {IERC721} `tokenId` token is transferred to this contract via {IERC721-safeTransferFrom}
* by `operator` from `from`, this function is called.
*
* It must return its Solidity selector to confirm the token transfer.
* If any other value is returned or the interface is not implemented by the recipient, the transfer will be reverted.
*
* The selector can be obtained in Solidity with `IERC721.onERC721Received.selector`.
*/
function onERC721Received(address operator, address from, uint256 tokenId, bytes calldata data) external returns (bytes4);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.6.0;
interface LinkTokenInterface {
function allowance(address owner, address spender) external view returns (uint256 remaining);
function approve(address spender, uint256 value) external returns (bool success);
function balanceOf(address owner) external view returns (uint256 balance);
function decimals() external view returns (uint8 decimalPlaces);
function decreaseApproval(address spender, uint256 addedValue) external returns (bool success);
function increaseApproval(address spender, uint256 subtractedValue) external;
function name() external view returns (string memory tokenName);
function symbol() external view returns (string memory tokenSymbol);
function totalSupply() external view returns (uint256 totalTokensIssued);
function transfer(address to, uint256 value) external returns (bool success);
function transferAndCall(address to, uint256 value, bytes calldata data) external returns (bool success);
function transferFrom(address from, address to, uint256 value) external returns (bool success);
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
import "../utils/Context.sol";
/**
* @dev Contract module which provides a basic access control mechanism, where
* there is an account (an owner) that can be granted exclusive access to
* specific functions.
*
* By default, the owner account will be the one that deploys the contract. This
* can later be changed with {transferOwnership}.
*
* This module is used through inheritance. It will make available the modifier
* `onlyOwner`, which can be applied to your functions to restrict their use to
* the owner.
*/
abstract contract Ownable is Context {
address private _owner;
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
/**
* @dev Initializes the contract setting the deployer as the initial owner.
*/
constructor () internal {
address msgSender = _msgSender();
_owner = msgSender;
emit OwnershipTransferred(address(0), msgSender);
}
/**
* @dev Returns the address of the current owner.
*/
function owner() public view virtual returns (address) {
return _owner;
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
require(owner() == _msgSender(), "Ownable: caller is not the owner");
_;
}
/**
* @dev Leaves the contract without owner. It will not be possible to call
* `onlyOwner` functions anymore. Can only be called by the current owner.
*
* NOTE: Renouncing ownership will leave the contract without an owner,
* thereby removing any functionality that is only available to the owner.
*/
function renounceOwnership() public virtual onlyOwner {
emit OwnershipTransferred(_owner, address(0));
_owner = address(0);
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Can only be called by the current owner.
*/
function transferOwnership(address newOwner) public virtual onlyOwner {
require(newOwner != address(0), "Ownable: new owner is the zero address");
emit OwnershipTransferred(_owner, newOwner);
_owner = newOwner;
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.6.0;
interface PointerInterface {
function getAddress() external view returns (address);
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
/**
* @dev Wrappers over Solidity's arithmetic operations with added overflow
* checks.
*
* Arithmetic operations in Solidity wrap on overflow. This can easily result
* in bugs, because programmers usually assume that an overflow raises an
* error, which is the standard behavior in high level programming languages.
* `SafeMath` restores this intuition by reverting the transaction when an
* operation overflows.
*
* Using this library instead of the unchecked operations eliminates an entire
* class of bugs, so it's recommended to use it always.
*/
library SafeMath {
/**
* @dev Returns the addition of two unsigned integers, with an overflow flag.
*
* _Available since v3.4._
*/
function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
uint256 c = a + b;
if (c < a) return (false, 0);
return (true, c);
}
/**
* @dev Returns the substraction of two unsigned integers, with an overflow flag.
*
* _Available since v3.4._
*/
function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
if (b > a) return (false, 0);
return (true, a - b);
}
/**
* @dev Returns the multiplication of two unsigned integers, with an overflow flag.
*
* _Available since v3.4._
*/
function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
// Gas optimization: this is cheaper than requiring 'a' not being zero, but the
// benefit is lost if 'b' is also tested.
// See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
if (a == 0) return (true, 0);
uint256 c = a * b;
if (c / a != b) return (false, 0);
return (true, c);
}
/**
* @dev Returns the division of two unsigned integers, with a division by zero flag.
*
* _Available since v3.4._
*/
function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
if (b == 0) return (false, 0);
return (true, a / b);
}
/**
* @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
*
* _Available since v3.4._
*/
function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
if (b == 0) return (false, 0);
return (true, a % b);
}
/**
* @dev Returns the addition of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `+` operator.
*
* Requirements:
*
* - Addition cannot overflow.
*/
function add(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a + b;
require(c >= a, "SafeMath: addition overflow");
return c;
}
/**
* @dev Returns the subtraction of two unsigned integers, reverting on
* overflow (when the result is negative).
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
*
* - Subtraction cannot overflow.
*/
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
require(b <= a, "SafeMath: subtraction overflow");
return a - b;
}
/**
* @dev Returns the multiplication of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `*` operator.
*
* Requirements:
*
* - Multiplication cannot overflow.
*/
function mul(uint256 a, uint256 b) internal pure returns (uint256) {
if (a == 0) return 0;
uint256 c = a * b;
require(c / a == b, "SafeMath: multiplication overflow");
return c;
}
/**
* @dev Returns the integer division of two unsigned integers, reverting on
* division by zero. The result is rounded towards zero.
*
* Counterpart to Solidity's `/` operator. Note: this function uses a
* `revert` opcode (which leaves remaining gas untouched) while Solidity
* uses an invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
*
* - The divisor cannot be zero.
*/
function div(uint256 a, uint256 b) internal pure returns (uint256) {
require(b > 0, "SafeMath: division by zero");
return a / b;
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* reverting when dividing by zero.
*
* Counterpart to Solidity's `%` operator. This function uses a `revert`
* opcode (which leaves remaining gas untouched) while Solidity uses an
* invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
*
* - The divisor cannot be zero.
*/
function mod(uint256 a, uint256 b) internal pure returns (uint256) {
require(b > 0, "SafeMath: modulo by zero");
return a % b;
}
/**
* @dev Returns the subtraction of two unsigned integers, reverting with custom message on
* overflow (when the result is negative).
*
* CAUTION: This function is deprecated because it requires allocating memory for the error
* message unnecessarily. For custom revert reasons use {trySub}.
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
*
* - Subtraction cannot overflow.
*/
function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
require(b <= a, errorMessage);
return a - b;
}
/**
* @dev Returns the integer division of two unsigned integers, reverting with custom message on
* division by zero. The result is rounded towards zero.
*
* CAUTION: This function is deprecated because it requires allocating memory for the error
* message unnecessarily. For custom revert reasons use {tryDiv}.
*
* Counterpart to Solidity's `/` operator. Note: this function uses a
* `revert` opcode (which leaves remaining gas untouched) while Solidity
* uses an invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
*
* - The divisor cannot be zero.
*/
function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
require(b > 0, errorMessage);
return a / b;
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* reverting with custom message when dividing by zero.
*
* CAUTION: This function is deprecated because it requires allocating memory for the error
* message unnecessarily. For custom revert reasons use {tryMod}.
*
* Counterpart to Solidity's `%` operator. This function uses a `revert`
* opcode (which leaves remaining gas untouched) while Solidity uses an
* invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
*
* - The divisor cannot be zero.
*/
function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
require(b > 0, errorMessage);
return a % b;
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.6.0;
/**
* @dev Wrappers over Solidity's arithmetic operations with added overflow
* checks.
*
* Arithmetic operations in Solidity wrap on overflow. This can easily result
* in bugs, because programmers usually assume that an overflow raises an
* error, which is the standard behavior in high level programming languages.
* `SafeMath` restores this intuition by reverting the transaction when an
* operation overflows.
*
* Using this library instead of the unchecked operations eliminates an entire
* class of bugs, so it's recommended to use it always.
*/
library SafeMathChainlink {
/**
* @dev Returns the addition of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `+` operator.
*
* Requirements:
* - Addition cannot overflow.
*/
function add(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a + b;
require(c >= a, "SafeMath: addition overflow");
return c;
}
/**
* @dev Returns the subtraction of two unsigned integers, reverting on
* overflow (when the result is negative).
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
* - Subtraction cannot overflow.
*/
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
require(b <= a, "SafeMath: subtraction overflow");
uint256 c = a - b;
return c;
}
/**
* @dev Returns the multiplication of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `*` operator.
*
* Requirements:
* - Multiplication cannot overflow.
*/
function mul(uint256 a, uint256 b) internal pure returns (uint256) {
// Gas optimization: this is cheaper than requiring 'a' not being zero, but the
// benefit is lost if 'b' is also tested.
// See: https://github.com/OpenZeppelin/openzeppelin-solidity/pull/522
if (a == 0) {
return 0;
}
uint256 c = a * b;
require(c / a == b, "SafeMath: multiplication overflow");
return c;
}
/**
* @dev Returns the integer division of two unsigned integers. Reverts on
* division by zero. The result is rounded towards zero.
*
* Counterpart to Solidity's `/` operator. Note: this function uses a
* `revert` opcode (which leaves remaining gas untouched) while Solidity
* uses an invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
* - The divisor cannot be zero.
*/
function div(uint256 a, uint256 b) internal pure returns (uint256) {
// Solidity only automatically asserts when dividing by 0
require(b > 0, "SafeMath: division by zero");
uint256 c = a / b;
// assert(a == b * c + a % b); // There is no case in which this doesn't hold
return c;
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* Reverts when dividing by zero.
*
* Counterpart to Solidity's `%` operator. This function uses a `revert`
* opcode (which leaves remaining gas untouched) while Solidity uses an
* invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
* - The divisor cannot be zero.
*/
function mod(uint256 a, uint256 b) internal pure returns (uint256) {
require(b != 0, "SafeMath: modulo by zero");
return a % b;
}
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
/**
* @dev String operations.
*/
library Strings {
/**
* @dev Converts a `uint256` to its ASCII `string` representation.
*/
function toString(uint256 value) internal pure returns (string memory) {
// Inspired by OraclizeAPI's implementation - MIT licence
// https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol
if (value == 0) {
return "0";
}
uint256 temp = value;
uint256 digits;
while (temp != 0) {
digits++;
temp /= 10;
}
bytes memory buffer = new bytes(digits);
uint256 index = digits - 1;
temp = value;
while (temp != 0) {
buffer[index--] = bytes1(uint8(48 + temp % 10));
temp /= 10;
}
return string(buffer);
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.6.0;
import "@chainlink/contracts/v0.6/vendor/SafeMathChainlink.sol";
import "@chainlink/contracts/v0.6/interfaces/LinkTokenInterface.sol";
import "@chainlink/contracts/v0.6/VRFRequestIDBase.sol";
// import "./vendor/SafeMathChainlink.sol";
// import "./interfaces/LinkTokenInterface.sol";
// import "./VRFRequestIDBase.sol";
/** ****************************************************************************
* @notice Interface for contracts using VRF randomness
* *****************************************************************************
* @dev PURPOSE
*
* @dev Reggie the Random Oracle (not his real job) wants to provide randomness
* @dev to Vera the verifier in such a way that Vera can be sure he's not
* @dev making his output up to suit himself. Reggie provides Vera a public key
* @dev to which he knows the secret key. Each time Vera provides a seed to
* @dev Reggie, he gives back a value which is computed completely
* @dev deterministically from the seed and the secret key.
*
* @dev Reggie provides a proof by which Vera can verify that the output was
* @dev correctly computed once Reggie tells it to her, but without that proof,
* @dev the output is indistinguishable to her from a uniform random sample
* @dev from the output space.
*
* @dev The purpose of this contract is to make it easy for unrelated contracts
* @dev to talk to Vera the verifier about the work Reggie is doing, to provide
* @dev simple access to a verifiable source of randomness.
* *****************************************************************************
* @dev USAGE
*
* @dev Calling contracts must inherit from VRFConsumerBase, and can
* @dev initialize VRFConsumerBase's attributes in their constructor as
* @dev shown:
*
* @dev contract VRFConsumer {
* @dev constuctor(<other arguments>, address _vrfCoordinator, address _link)
* @dev VRFConsumerBase(_vrfCoordinator, _link) public {
* @dev <initialization with other arguments goes here>
* @dev }
* @dev }
*
* @dev The oracle will have given you an ID for the VRF keypair they have
* @dev committed to (let's call it keyHash), and have told you the minimum LINK
* @dev price for VRF service. Make sure your contract has sufficient LINK, and
* @dev call requestRandomness(keyHash, fee, seed), where seed is the input you
* @dev want to generate randomness from.
*
* @dev Once the VRFCoordinator has received and validated the oracle's response
* @dev to your request, it will call your contract's fulfillRandomness method.
*
* @dev The randomness argument to fulfillRandomness is the actual random value
* @dev generated from your seed.
*
* @dev The requestId argument is generated from the keyHash and the seed by
* @dev makeRequestId(keyHash, seed). If your contract could have concurrent
* @dev requests open, you can use the requestId to track which seed is
* @dev associated with which randomness. See VRFRequestIDBase.sol for more
* @dev details. (See "SECURITY CONSIDERATIONS" for principles to keep in mind,
* @dev if your contract could have multiple requests in flight simultaneously.)
*
* @dev Colliding `requestId`s are cryptographically impossible as long as seeds
* @dev differ. (Which is critical to making unpredictable randomness! See the
* @dev next section.)
*
* *****************************************************************************
* @dev SECURITY CONSIDERATIONS
*
* @dev A method with the ability to call your fulfillRandomness method directly
* @dev could spoof a VRF response with any random value, so it's critical that
* @dev it cannot be directly called by anything other than this base contract
* @dev (specifically, by the VRFConsumerBase.rawFulfillRandomness method).
*
* @dev For your users to trust that your contract's random behavior is free
* @dev from malicious interference, it's best if you can write it so that all
* @dev behaviors implied by a VRF response are executed *during* your
* @dev fulfillRandomness method. If your contract must store the response (or
* @dev anything derived from it) and use it later, you must ensure that any
* @dev user-significant behavior which depends on that stored value cannot be
* @dev manipulated by a subsequent VRF request.
*
* @dev Similarly, both miners and the VRF oracle itself have some influence
* @dev over the order in which VRF responses appear on the blockchain, so if
* @dev your contract could have multiple VRF requests in flight simultaneously,
* @dev you must ensure that the order in which the VRF responses arrive cannot
* @dev be used to manipulate your contract's user-significant behavior.
*
* @dev Since the ultimate input to the VRF is mixed with the block hash of the
* @dev block in which the request is made, user-provided seeds have no impact
* @dev on its economic security properties. They are only included for API
* @dev compatability with previous versions of this contract.
*
* @dev Since the block hash of the block which contains the requestRandomness
* @dev call is mixed into the input to the VRF *last*, a sufficiently powerful
* @dev miner could, in principle, fork the blockchain to evict the block
* @dev containing the request, forcing the request to be included in a
* @dev different block with a different hash, and therefore a different input
* @dev to the VRF. However, such an attack would incur a substantial economic
* @dev cost. This cost scales with the number of blocks the VRF oracle waits
* @dev until it calls responds to a request.
*/
abstract contract VRFConsumerBase is VRFRequestIDBase {
using SafeMathChainlink for uint256;
/**
* @notice fulfillRandomness handles the VRF response. Your contract must
* @notice implement it. See "SECURITY CONSIDERATIONS" above for important
* @notice principles to keep in mind when implementing your fulfillRandomness
* @notice method.
*
* @dev VRFConsumerBase expects its subcontracts to have a method with this
* @dev signature, and will call it once it has verified the proof
* @dev associated with the randomness. (It is triggered via a call to
* @dev rawFulfillRandomness, below.)
*
* @param requestId The Id initially returned by requestRandomness
* @param randomness the VRF output
*/
function fulfillRandomness(bytes32 requestId, uint256 randomness)
internal virtual;
/**
* @notice requestRandomness initiates a request for VRF output given _seed
*
* @dev The fulfillRandomness method receives the output, once it's provided
* @dev by the Oracle, and verified by the vrfCoordinator.
*
* @dev The _keyHash must already be registered with the VRFCoordinator, and
* @dev the _fee must exceed the fee specified during registration of the
* @dev _keyHash.
*
* @dev The _seed parameter is vestigial, and is kept only for API
* @dev compatibility with older versions. It can't *hurt* to mix in some of
* @dev your own randomness, here, but it's not necessary because the VRF
* @dev oracle will mix the hash of the block containing your request into the
* @dev VRF seed it ultimately uses.
*
* @param _keyHash ID of public key against which randomness is generated
* @param _fee The amount of LINK to send with the request
* @param _seed seed mixed into the input of the VRF.
*
* @return requestId unique ID for this request
*
* @dev The returned requestId can be used to distinguish responses to
* @dev concurrent requests. It is passed as the first argument to
* @dev fulfillRandomness.
*/
function requestRandomness(bytes32 _keyHash, uint256 _fee, uint256 _seed)
internal returns (bytes32 requestId)
{
LINK_TOKEN_INTERFACE.transferAndCall(vrfCoordinator, _fee, abi.encode(_keyHash, _seed));
// This is the seed passed to VRFCoordinator. The oracle will mix this with
// the hash of the block containing this request to obtain the seed/input
// which is finally passed to the VRF cryptographic machinery.
uint256 vRFSeed = makeVRFInputSeed(_keyHash, _seed, address(this), nonces[_keyHash]);
// nonces[_keyHash] must stay in sync with
// VRFCoordinator.nonces[_keyHash][this], which was incremented by the above
// successful LINK_TOKEN_INTERFACE.transferAndCall (in VRFCoordinator.randomnessRequest).
// This provides protection against the user repeating their input seed,
// which would result in a predictable/duplicate output, if multiple such
// requests appeared in the same block.
nonces[_keyHash] = nonces[_keyHash].add(1);
return makeRequestId(_keyHash, vRFSeed);
}
LinkTokenInterface immutable internal LINK_TOKEN_INTERFACE;
address immutable private vrfCoordinator;
// Nonces for each VRF key from which randomness has been requested.
//
// Must stay in sync with VRFCoordinator[_keyHash][this]
mapping(bytes32 /* keyHash */ => uint256 /* nonce */) private nonces;
/**
* @param _vrfCoordinator address of VRFCoordinator contract
* @param _link address of LINK token contract
*
* @dev https://docs.chain.link/docs/link-token-contracts
*/
constructor(address _vrfCoordinator, address _link) public {
vrfCoordinator = _vrfCoordinator;
LINK_TOKEN_INTERFACE = LinkTokenInterface(_link);
}
// rawFulfillRandomness is called by VRFCoordinator when it receives a valid VRF
// proof. rawFulfillRandomness then calls fulfillRandomness, after validating
// the origin of the call
function rawFulfillRandomness(bytes32 requestId, uint256 randomness) external {
require(msg.sender == vrfCoordinator, "Only VRFCoordinator can fulfill");
fulfillRandomness(requestId, randomness);
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.6.0;
contract VRFRequestIDBase {
/**
* @notice returns the seed which is actually input to the VRF coordinator
*
* @dev To prevent repetition of VRF output due to repetition of the
* @dev user-supplied seed, that seed is combined in a hash with the
* @dev user-specific nonce, and the address of the consuming contract. The
* @dev risk of repetition is mostly mitigated by inclusion of a blockhash in
* @dev the final seed, but the nonce does protect against repetition in
* @dev requests which are included in a single block.
*
* @param _userSeed VRF seed input provided by user
* @param _requester Address of the requesting contract
* @param _nonce User-specific nonce at the time of the request
*/
function makeVRFInputSeed(bytes32 _keyHash, uint256 _userSeed,
address _requester, uint256 _nonce)
internal pure returns (uint256)
{
return uint256(keccak256(abi.encode(_keyHash, _userSeed, _requester, _nonce)));
}
/**
* @notice Returns the id for this request
* @param _keyHash The serviceAgreement ID to be used for this request
* @param _vRFInputSeed The seed to be passed directly to the VRF
* @return The id for this request
*
* @dev Note that _vRFInputSeed is not the seed passed by the consuming
* @dev contract, but the one generated by makeVRFInputSeed
*/
function makeRequestId(
bytes32 _keyHash, uint256 _vRFInputSeed) internal pure returns (bytes32) {
return keccak256(abi.encodePacked(_keyHash, _vRFInputSeed));
}
}
{
"compilationTarget": {
"contracts/CryptoTrunks.sol": "CryptoTrunks"
},
"evmVersion": "istanbul",
"libraries": {},
"metadata": {
"bytecodeHash": "ipfs"
},
"optimizer": {
"enabled": false,
"runs": 200
},
"remappings": []
}
[{"inputs":[],"stateMutability":"nonpayable","type":"constructor"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"owner","type":"address"},{"indexed":true,"internalType":"address","name":"approved","type":"address"},{"indexed":true,"internalType":"uint256","name":"tokenId","type":"uint256"}],"name":"Approval","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"owner","type":"address"},{"indexed":true,"internalType":"address","name":"operator","type":"address"},{"indexed":false,"internalType":"bool","name":"approved","type":"bool"}],"name":"ApprovalForAll","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"bytes32","name":"id","type":"bytes32"}],"name":"ChainlinkCancelled","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"bytes32","name":"id","type":"bytes32"}],"name":"ChainlinkFulfilled","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"bytes32","name":"id","type":"bytes32"}],"name":"ChainlinkRequested","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"previousOwner","type":"address"},{"indexed":true,"internalType":"address","name":"newOwner","type":"address"}],"name":"OwnershipTransferred","type":"event"},{"anonymous":false,"inputs":[{"indexed":false,"internalType":"bytes32","name":"requestId","type":"bytes32"},{"indexed":false,"internalType":"uint256","name":"tokenId","type":"uint256"},{"indexed":false,"internalType":"uint256","name":"resultId","type":"uint256"}],"name":"RemoteMintFulfilled","type":"event"},{"anonymous":false,"inputs":[{"indexed":false,"internalType":"bytes32","name":"requestId","type":"bytes32"},{"indexed":false,"internalType":"uint256","name":"firstTokenId","type":"uint256"},{"indexed":false,"internalType":"uint256","name":"resultId","type":"uint256"}],"name":"RemoteMintTwentyFulfilled","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"from","type":"address"},{"indexed":true,"internalType":"address","name":"to","type":"address"},{"indexed":true,"internalType":"uint256","name":"tokenId","type":"uint256"}],"name":"Transfer","type":"event"},{"inputs":[{"internalType":"address","name":"to","type":"address"},{"internalType":"uint256","name":"tokenId","type":"uint256"}],"name":"approve","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"owner","type":"address"}],"name":"balanceOf","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"baseURI","outputs":[{"internalType":"string","name":"","type":"string"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"fetchGenesisSeedFromVRF","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"bytes32","name":"_requestId","type":"bytes32"},{"internalType":"uint256","name":"_resultId","type":"uint256"}],"name":"fulfill","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"bytes32","name":"_requestId","type":"bytes32"},{"internalType":"uint256","name":"_resultId","type":"uint256"}],"name":"fulfillTwenty","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"tokenId","type":"uint256"}],"name":"getApproved","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"getBaseFeeTier","outputs":[{"internalType":"uint256","name":"baseFeeTier","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"getFeeTier","outputs":[{"internalType":"uint256","name":"feeTier","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"getGenerativeMinted","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"getGenesisMinted","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"getGenesisRandomSeed","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"getOracle","outputs":[{"internalType":"address","name":"","type":"address"},{"internalType":"bytes32","name":"","type":"bytes32"},{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"owner","type":"address"},{"internalType":"address","name":"operator","type":"address"}],"name":"isApprovedForAll","outputs":[{"internalType":"bool","name":"","type":"bool"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint256","name":"numberToMint","type":"uint256"}],"name":"mintGenesisTrunk","outputs":[{"internalType":"uint256[]","name":"tokenIds","type":"uint256[]"}],"stateMutability":"payable","type":"function"},{"inputs":[{"internalType":"uint256","name":"randomSeed","type":"uint256"},{"internalType":"bool","name":"isBasic","type":"bool"}],"name":"mintTrunk","outputs":[{"internalType":"uint256","name":"tokenId","type":"uint256"}],"stateMutability":"payable","type":"function"},{"inputs":[],"name":"mintTwentyTrunks","outputs":[{"internalType":"uint256","name":"tokenId","type":"uint256"}],"stateMutability":"payable","type":"function"},{"inputs":[],"name":"name","outputs":[{"internalType":"string","name":"","type":"string"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"owner","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint256","name":"tokenId","type":"uint256"}],"name":"ownerOf","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"paused","outputs":[{"internalType":"bool","name":"","type":"bool"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"bytes32","name":"requestId","type":"bytes32"},{"internalType":"uint256","name":"randomness","type":"uint256"}],"name":"rawFulfillRandomness","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"renounceOwnership","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"from","type":"address"},{"internalType":"address","name":"to","type":"address"},{"internalType":"uint256","name":"tokenId","type":"uint256"}],"name":"safeTransferFrom","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"from","type":"address"},{"internalType":"address","name":"to","type":"address"},{"internalType":"uint256","name":"tokenId","type":"uint256"},{"internalType":"bytes","name":"_data","type":"bytes"}],"name":"safeTransferFrom","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"operator","type":"address"},{"internalType":"bool","name":"approved","type":"bool"}],"name":"setApprovalForAll","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"string","name":"baseURI_","type":"string"}],"name":"setBaseURI","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"bytes4","name":"interfaceId","type":"bytes4"}],"name":"supportsInterface","outputs":[{"internalType":"bool","name":"","type":"bool"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"symbol","outputs":[{"internalType":"string","name":"","type":"string"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"togglePaused","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"index","type":"uint256"}],"name":"tokenByIndex","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"owner","type":"address"},{"internalType":"uint256","name":"index","type":"uint256"}],"name":"tokenOfOwnerByIndex","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint256","name":"tokenId","type":"uint256"}],"name":"tokenURI","outputs":[{"internalType":"string","name":"","type":"string"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"totalSupply","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"from","type":"address"},{"internalType":"address","name":"to","type":"address"},{"internalType":"uint256","name":"tokenId","type":"uint256"}],"name":"transferFrom","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"newOwner","type":"address"}],"name":"transferOwnership","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"_oracle","type":"address"},{"internalType":"bytes32","name":"_jobId","type":"bytes32"},{"internalType":"uint256","name":"_fee","type":"uint256"}],"name":"updateOracle","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"withdraw","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"withdrawLink","outputs":[],"stateMutability":"nonpayable","type":"function"}]