Contract Name:
LeftGallery
Contract Source Code:
File 1 of 1 : LeftGallery
// https://github.com/left-gallery/contracts/
//
// Forked from folia-app/folia-contracts: https://github.com/folia-app/folia-contracts
// Many thanks to Billy Rennekamp <https://github.com/okwme> and Folia <https://www.folia.app/> 💚
//
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// File openzeppelin-solidity/contracts/GSN/[email protected]
pragma solidity ^0.5.0;
/*
* @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.
*/
contract Context {
// Empty internal constructor, to prevent people from mistakenly deploying
// an instance of this contract, which should be used via inheritance.
constructor() internal {}
// solhint-disable-previous-line no-empty-blocks
function _msgSender() internal view returns (address payable) {
return msg.sender;
}
function _msgData() internal view returns (bytes memory) {
this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
return msg.data;
}
}
// File openzeppelin-solidity/contracts/introspection/[email protected]
pragma solidity ^0.5.0;
/**
* @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);
}
// File openzeppelin-solidity/contracts/token/ERC721/[email protected]
pragma solidity ^0.5.0;
/**
* @dev Required interface of an ERC721 compliant contract.
*/
contract IERC721 is IERC165 {
event Transfer(
address indexed from,
address indexed to,
uint256 indexed tokenId
);
event Approval(
address indexed owner,
address indexed approved,
uint256 indexed tokenId
);
event ApprovalForAll(
address indexed owner,
address indexed operator,
bool approved
);
/**
* @dev Returns the number of NFTs in `owner`'s account.
*/
function balanceOf(address owner) public view returns (uint256 balance);
/**
* @dev Returns the owner of the NFT specified by `tokenId`.
*/
function ownerOf(uint256 tokenId) public view returns (address owner);
/**
* @dev Transfers a specific NFT (`tokenId`) from one account (`from`) to
* another (`to`).
*
*
*
* Requirements:
* - `from`, `to` cannot be zero.
* - `tokenId` must be owned by `from`.
* - If the caller is not `from`, it must be have been allowed to move this
* NFT by either {approve} or {setApprovalForAll}.
*/
function safeTransferFrom(
address from,
address to,
uint256 tokenId
) public;
/**
* @dev Transfers a specific NFT (`tokenId`) from one account (`from`) to
* another (`to`).
*
* Requirements:
* - If the caller is not `from`, it must be approved to move this NFT by
* either {approve} or {setApprovalForAll}.
*/
function transferFrom(
address from,
address to,
uint256 tokenId
) public;
function approve(address to, uint256 tokenId) public;
function getApproved(uint256 tokenId)
public
view
returns (address operator);
function setApprovalForAll(address operator, bool _approved) public;
function isApprovedForAll(address owner, address operator)
public
view
returns (bool);
function safeTransferFrom(
address from,
address to,
uint256 tokenId,
bytes memory data
) public;
}
// File openzeppelin-solidity/contracts/token/ERC721/[email protected]
pragma solidity ^0.5.0;
/**
* @title ERC721 token receiver interface
* @dev Interface for any contract that wants to support safeTransfers
* from ERC721 asset contracts.
*/
contract IERC721Receiver {
/**
* @notice Handle the receipt of an NFT
* @dev The ERC721 smart contract calls this function on the recipient
* after a {IERC721-safeTransferFrom}. This function MUST return the function selector,
* otherwise the caller will revert the transaction. The selector to be
* returned can be obtained as `this.onERC721Received.selector`. This
* function MAY throw to revert and reject the transfer.
* Note: the ERC721 contract address is always the message sender.
* @param operator The address which called `safeTransferFrom` function
* @param from The address which previously owned the token
* @param tokenId The NFT identifier which is being transferred
* @param data Additional data with no specified format
* @return bytes4 `bytes4(keccak256("onERC721Received(address,address,uint256,bytes)"))`
*/
function onERC721Received(
address operator,
address from,
uint256 tokenId,
bytes memory data
) public returns (bytes4);
}
// File openzeppelin-solidity/contracts/math/[email protected]
pragma solidity ^0.5.0;
/**
* @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, 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) {
return sub(a, b, "SafeMath: subtraction overflow");
}
/**
* @dev Returns the subtraction of two unsigned integers, reverting with custom message on
* overflow (when the result is negative).
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
* - Subtraction cannot overflow.
*
* _Available since v2.4.0._
*/
function sub(
uint256 a,
uint256 b,
string memory errorMessage
) internal pure returns (uint256) {
require(b <= a, errorMessage);
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-contracts/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) {
return div(a, b, "SafeMath: division by zero");
}
/**
* @dev Returns the integer division of two unsigned integers. Reverts with custom message 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.
*
* _Available since v2.4.0._
*/
function div(
uint256 a,
uint256 b,
string memory errorMessage
) internal pure returns (uint256) {
// Solidity only automatically asserts when dividing by 0
require(b > 0, errorMessage);
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) {
return mod(a, b, "SafeMath: modulo by zero");
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* Reverts with custom message 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.
*
* _Available since v2.4.0._
*/
function mod(
uint256 a,
uint256 b,
string memory errorMessage
) internal pure returns (uint256) {
require(b != 0, errorMessage);
return a % b;
}
}
// File openzeppelin-solidity/contracts/utils/[email protected]
pragma solidity ^0.5.5;
/**
* @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) {
// According to EIP-1052, 0x0 is the value returned for not-yet created accounts
// and 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470 is returned
// for accounts without code, i.e. `keccak256('')`
bytes32 codehash;
bytes32 accountHash =
0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470;
// solhint-disable-next-line no-inline-assembly
assembly {
codehash := extcodehash(account)
}
return (codehash != accountHash && codehash != 0x0);
}
/**
* @dev Converts an `address` into `address payable`. Note that this is
* simply a type cast: the actual underlying value is not changed.
*
* _Available since v2.4.0._
*/
function toPayable(address account)
internal
pure
returns (address payable)
{
return address(uint160(account));
}
/**
* @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].
*
* _Available since v2.4.0._
*/
function sendValue(address payable recipient, uint256 amount) internal {
require(
address(this).balance >= amount,
"Address: insufficient balance"
);
// solhint-disable-next-line avoid-call-value
(bool success, ) = recipient.call.value(amount)("");
require(
success,
"Address: unable to send value, recipient may have reverted"
);
}
}
// File openzeppelin-solidity/contracts/drafts/[email protected]
pragma solidity ^0.5.0;
/**
* @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);
}
}
// File openzeppelin-solidity/contracts/introspection/[email protected]
pragma solidity ^0.5.0;
/**
* @dev Implementation of the {IERC165} interface.
*
* Contracts may inherit from this and call {_registerInterface} to declare
* their support of an interface.
*/
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)
external
view
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 {
require(interfaceId != 0xffffffff, "ERC165: invalid interface id");
_supportedInterfaces[interfaceId] = true;
}
}
// File openzeppelin-solidity/contracts/token/ERC721/[email protected]
pragma solidity ^0.5.0;
/**
* @title ERC721 Non-Fungible Token Standard basic implementation
* @dev see https://eips.ethereum.org/EIPS/eip-721
*/
contract ERC721 is Context, ERC165, IERC721 {
using SafeMath for uint256;
using Address for address;
using Counters for Counters.Counter;
// 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 token ID to owner
mapping(uint256 => address) private _tokenOwner;
// Mapping from token ID to approved address
mapping(uint256 => address) private _tokenApprovals;
// Mapping from owner to number of owned token
mapping(address => Counters.Counter) private _ownedTokensCount;
// Mapping from owner to operator approvals
mapping(address => mapping(address => bool)) private _operatorApprovals;
/*
* 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 ^ 0xe985e9c ^ 0x23b872dd ^ 0x42842e0e ^ 0xb88d4fde == 0x80ac58cd
*/
bytes4 private constant _INTERFACE_ID_ERC721 = 0x80ac58cd;
constructor() public {
// register the supported interfaces to conform to ERC721 via ERC165
_registerInterface(_INTERFACE_ID_ERC721);
}
/**
* @dev Gets the balance of the specified address.
* @param owner address to query the balance of
* @return uint256 representing the amount owned by the passed address
*/
function balanceOf(address owner) public view returns (uint256) {
require(
owner != address(0),
"ERC721: balance query for the zero address"
);
return _ownedTokensCount[owner].current();
}
/**
* @dev Gets the owner of the specified token ID.
* @param tokenId uint256 ID of the token to query the owner of
* @return address currently marked as the owner of the given token ID
*/
function ownerOf(uint256 tokenId) public view returns (address) {
address owner = _tokenOwner[tokenId];
require(
owner != address(0),
"ERC721: owner query for nonexistent token"
);
return owner;
}
/**
* @dev Approves another address to transfer the given token ID
* The zero address indicates there is no approved address.
* There can only be one approved address per token at a given time.
* Can only be called by the token owner or an approved operator.
* @param to address to be approved for the given token ID
* @param tokenId uint256 ID of the token to be approved
*/
function approve(address to, uint256 tokenId) public {
address owner = ownerOf(tokenId);
require(to != owner, "ERC721: approval to current owner");
require(
_msgSender() == owner || isApprovedForAll(owner, _msgSender()),
"ERC721: approve caller is not owner nor approved for all"
);
_tokenApprovals[tokenId] = to;
emit Approval(owner, to, tokenId);
}
/**
* @dev Gets the approved address for a token ID, or zero if no address set
* Reverts if the token ID does not exist.
* @param tokenId uint256 ID of the token to query the approval of
* @return address currently approved for the given token ID
*/
function getApproved(uint256 tokenId) public view returns (address) {
require(
_exists(tokenId),
"ERC721: approved query for nonexistent token"
);
return _tokenApprovals[tokenId];
}
/**
* @dev Sets or unsets the approval of a given operator
* An operator is allowed to transfer all tokens of the sender on their behalf.
* @param to operator address to set the approval
* @param approved representing the status of the approval to be set
*/
function setApprovalForAll(address to, bool approved) public {
require(to != _msgSender(), "ERC721: approve to caller");
_operatorApprovals[_msgSender()][to] = approved;
emit ApprovalForAll(_msgSender(), to, approved);
}
/**
* @dev Tells whether an operator is approved by a given owner.
* @param owner owner address which you want to query the approval of
* @param operator operator address which you want to query the approval of
* @return bool whether the given operator is approved by the given owner
*/
function isApprovedForAll(address owner, address operator)
public
view
returns (bool)
{
return _operatorApprovals[owner][operator];
}
/**
* @dev Transfers the ownership of a given token ID to another address.
* Usage of this method is discouraged, use {safeTransferFrom} whenever possible.
* Requires the msg.sender to be the owner, approved, or operator.
* @param from current owner of the token
* @param to address to receive the ownership of the given token ID
* @param tokenId uint256 ID of the token to be transferred
*/
function transferFrom(
address from,
address to,
uint256 tokenId
) public {
//solhint-disable-next-line max-line-length
require(
_isApprovedOrOwner(_msgSender(), tokenId),
"ERC721: transfer caller is not owner nor approved"
);
_transferFrom(from, to, tokenId);
}
/**
* @dev Safely transfers the ownership of a given token ID to another address
* If the target address is a contract, it must implement {IERC721Receiver-onERC721Received},
* which is called upon a safe transfer, and return the magic value
* `bytes4(keccak256("onERC721Received(address,address,uint256,bytes)"))`; otherwise,
* the transfer is reverted.
* Requires the msg.sender to be the owner, approved, or operator
* @param from current owner of the token
* @param to address to receive the ownership of the given token ID
* @param tokenId uint256 ID of the token to be transferred
*/
function safeTransferFrom(
address from,
address to,
uint256 tokenId
) public {
safeTransferFrom(from, to, tokenId, "");
}
/**
* @dev Safely transfers the ownership of a given token ID to another address
* If the target address is a contract, it must implement {IERC721Receiver-onERC721Received},
* which is called upon a safe transfer, and return the magic value
* `bytes4(keccak256("onERC721Received(address,address,uint256,bytes)"))`; otherwise,
* the transfer is reverted.
* Requires the _msgSender() to be the owner, approved, or operator
* @param from current owner of the token
* @param to address to receive the ownership of the given token ID
* @param tokenId uint256 ID of the token to be transferred
* @param _data bytes data to send along with a safe transfer check
*/
function safeTransferFrom(
address from,
address to,
uint256 tokenId,
bytes memory _data
) public {
require(
_isApprovedOrOwner(_msgSender(), tokenId),
"ERC721: transfer caller is not owner nor approved"
);
_safeTransferFrom(from, to, tokenId, _data);
}
/**
* @dev Safely transfers the ownership of a given token ID to another address
* If the target address is a contract, it must implement `onERC721Received`,
* which is called upon a safe transfer, and return the magic value
* `bytes4(keccak256("onERC721Received(address,address,uint256,bytes)"))`; otherwise,
* the transfer is reverted.
* Requires the msg.sender to be the owner, approved, or operator
* @param from current owner of the token
* @param to address to receive the ownership of the given token ID
* @param tokenId uint256 ID of the token to be transferred
* @param _data bytes data to send along with a safe transfer check
*/
function _safeTransferFrom(
address from,
address to,
uint256 tokenId,
bytes memory _data
) internal {
_transferFrom(from, to, tokenId);
require(
_checkOnERC721Received(from, to, tokenId, _data),
"ERC721: transfer to non ERC721Receiver implementer"
);
}
/**
* @dev Returns whether the specified token exists.
* @param tokenId uint256 ID of the token to query the existence of
* @return bool whether the token exists
*/
function _exists(uint256 tokenId) internal view returns (bool) {
address owner = _tokenOwner[tokenId];
return owner != address(0);
}
/**
* @dev Returns whether the given spender can transfer a given token ID.
* @param spender address of the spender to query
* @param tokenId uint256 ID of the token to be transferred
* @return bool whether the msg.sender is approved for the given token ID,
* is an operator of the owner, or is the owner of the token
*/
function _isApprovedOrOwner(address spender, uint256 tokenId)
internal
view
returns (bool)
{
require(
_exists(tokenId),
"ERC721: operator query for nonexistent token"
);
address owner = ownerOf(tokenId);
return (spender == owner ||
getApproved(tokenId) == spender ||
isApprovedForAll(owner, spender));
}
/**
* @dev Internal function to safely mint a new token.
* Reverts if the given token ID already exists.
* If the target address is a contract, it must implement `onERC721Received`,
* which is called upon a safe transfer, and return the magic value
* `bytes4(keccak256("onERC721Received(address,address,uint256,bytes)"))`; otherwise,
* the transfer is reverted.
* @param to The address that will own the minted token
* @param tokenId uint256 ID of the token to be minted
*/
function _safeMint(address to, uint256 tokenId) internal {
_safeMint(to, tokenId, "");
}
/**
* @dev Internal function to safely mint a new token.
* Reverts if the given token ID already exists.
* If the target address is a contract, it must implement `onERC721Received`,
* which is called upon a safe transfer, and return the magic value
* `bytes4(keccak256("onERC721Received(address,address,uint256,bytes)"))`; otherwise,
* the transfer is reverted.
* @param to The address that will own the minted token
* @param tokenId uint256 ID of the token to be minted
* @param _data bytes data to send along with a safe transfer check
*/
function _safeMint(
address to,
uint256 tokenId,
bytes memory _data
) internal {
_mint(to, tokenId);
require(
_checkOnERC721Received(address(0), to, tokenId, _data),
"ERC721: transfer to non ERC721Receiver implementer"
);
}
/**
* @dev Internal function to mint a new token.
* Reverts if the given token ID already exists.
* @param to The address that will own the minted token
* @param tokenId uint256 ID of the token to be minted
*/
function _mint(address to, uint256 tokenId) internal {
require(to != address(0), "ERC721: mint to the zero address");
require(!_exists(tokenId), "ERC721: token already minted");
_tokenOwner[tokenId] = to;
_ownedTokensCount[to].increment();
emit Transfer(address(0), to, tokenId);
}
/**
* @dev Internal function to burn a specific token.
* Reverts if the token does not exist.
* Deprecated, use {_burn} instead.
* @param owner owner of the token to burn
* @param tokenId uint256 ID of the token being burned
*/
function _burn(address owner, uint256 tokenId) internal {
require(
ownerOf(tokenId) == owner,
"ERC721: burn of token that is not own"
);
_clearApproval(tokenId);
_ownedTokensCount[owner].decrement();
_tokenOwner[tokenId] = address(0);
emit Transfer(owner, address(0), tokenId);
}
/**
* @dev Internal function to burn a specific token.
* Reverts if the token does not exist.
* @param tokenId uint256 ID of the token being burned
*/
function _burn(uint256 tokenId) internal {
_burn(ownerOf(tokenId), tokenId);
}
/**
* @dev Internal function to transfer ownership of a given token ID to another address.
* As opposed to {transferFrom}, this imposes no restrictions on msg.sender.
* @param from current owner of the token
* @param to address to receive the ownership of the given token ID
* @param tokenId uint256 ID of the token to be transferred
*/
function _transferFrom(
address from,
address to,
uint256 tokenId
) internal {
require(
ownerOf(tokenId) == from,
"ERC721: transfer of token that is not own"
);
require(to != address(0), "ERC721: transfer to the zero address");
_clearApproval(tokenId);
_ownedTokensCount[from].decrement();
_ownedTokensCount[to].increment();
_tokenOwner[tokenId] = to;
emit Transfer(from, to, tokenId);
}
/**
* @dev Internal function to invoke {IERC721Receiver-onERC721Received} on a target address.
* The call is not executed if the target address is not a contract.
*
* This is an internal detail of the `ERC721` contract and its use is deprecated.
* @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
) internal returns (bool) {
if (!to.isContract()) {
return true;
}
// solhint-disable-next-line avoid-low-level-calls
(bool success, bytes memory returndata) =
to.call(
abi.encodeWithSelector(
IERC721Receiver(to).onERC721Received.selector,
_msgSender(),
from,
tokenId,
_data
)
);
if (!success) {
if (returndata.length > 0) {
// solhint-disable-next-line no-inline-assembly
assembly {
let returndata_size := mload(returndata)
revert(add(32, returndata), returndata_size)
}
} else {
revert("ERC721: transfer to non ERC721Receiver implementer");
}
} else {
bytes4 retval = abi.decode(returndata, (bytes4));
return (retval == _ERC721_RECEIVED);
}
}
/**
* @dev Private function to clear current approval of a given token ID.
* @param tokenId uint256 ID of the token to be transferred
*/
function _clearApproval(uint256 tokenId) private {
if (_tokenApprovals[tokenId] != address(0)) {
_tokenApprovals[tokenId] = address(0);
}
}
}
// File openzeppelin-solidity/contracts/token/ERC721/[email protected]
pragma solidity ^0.5.0;
/**
* @title ERC-721 Non-Fungible Token Standard, optional enumeration extension
* @dev See https://eips.ethereum.org/EIPS/eip-721
*/
contract IERC721Enumerable is IERC721 {
function totalSupply() public view returns (uint256);
function tokenOfOwnerByIndex(address owner, uint256 index)
public
view
returns (uint256 tokenId);
function tokenByIndex(uint256 index) public view returns (uint256);
}
// File openzeppelin-solidity/contracts/token/ERC721/[email protected]
pragma solidity ^0.5.0;
/**
* @title ERC-721 Non-Fungible Token with optional enumeration extension logic
* @dev See https://eips.ethereum.org/EIPS/eip-721
*/
contract ERC721Enumerable is Context, ERC165, ERC721, IERC721Enumerable {
// Mapping from owner to list of owned token IDs
mapping(address => uint256[]) private _ownedTokens;
// Mapping from token ID to index of the owner tokens list
mapping(uint256 => uint256) private _ownedTokensIndex;
// Array with all token ids, used for enumeration
uint256[] private _allTokens;
// Mapping from token id to position in the allTokens array
mapping(uint256 => uint256) private _allTokensIndex;
/*
* 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 Constructor function.
*/
constructor() public {
// register the supported interface to conform to ERC721Enumerable via ERC165
_registerInterface(_INTERFACE_ID_ERC721_ENUMERABLE);
}
/**
* @dev Gets the token ID at a given index of the tokens list of the requested owner.
* @param owner address owning the tokens list to be accessed
* @param index uint256 representing the index to be accessed of the requested tokens list
* @return uint256 token ID at the given index of the tokens list owned by the requested address
*/
function tokenOfOwnerByIndex(address owner, uint256 index)
public
view
returns (uint256)
{
require(
index < balanceOf(owner),
"ERC721Enumerable: owner index out of bounds"
);
return _ownedTokens[owner][index];
}
/**
* @dev Gets the total amount of tokens stored by the contract.
* @return uint256 representing the total amount of tokens
*/
function totalSupply() public view returns (uint256) {
return _allTokens.length;
}
/**
* @dev Gets the token ID at a given index of all the tokens in this contract
* Reverts if the index is greater or equal to the total number of tokens.
* @param index uint256 representing the index to be accessed of the tokens list
* @return uint256 token ID at the given index of the tokens list
*/
function tokenByIndex(uint256 index) public view returns (uint256) {
require(
index < totalSupply(),
"ERC721Enumerable: global index out of bounds"
);
return _allTokens[index];
}
/**
* @dev Internal function to transfer ownership of a given token ID to another address.
* As opposed to transferFrom, this imposes no restrictions on msg.sender.
* @param from current owner of the token
* @param to address to receive the ownership of the given token ID
* @param tokenId uint256 ID of the token to be transferred
*/
function _transferFrom(
address from,
address to,
uint256 tokenId
) internal {
super._transferFrom(from, to, tokenId);
_removeTokenFromOwnerEnumeration(from, tokenId);
_addTokenToOwnerEnumeration(to, tokenId);
}
/**
* @dev Internal function to mint a new token.
* Reverts if the given token ID already exists.
* @param to address the beneficiary that will own the minted token
* @param tokenId uint256 ID of the token to be minted
*/
function _mint(address to, uint256 tokenId) internal {
super._mint(to, tokenId);
_addTokenToOwnerEnumeration(to, tokenId);
_addTokenToAllTokensEnumeration(tokenId);
}
/**
* @dev Internal function to burn a specific token.
* Reverts if the token does not exist.
* Deprecated, use {ERC721-_burn} instead.
* @param owner owner of the token to burn
* @param tokenId uint256 ID of the token being burned
*/
function _burn(address owner, uint256 tokenId) internal {
super._burn(owner, tokenId);
_removeTokenFromOwnerEnumeration(owner, tokenId);
// Since tokenId will be deleted, we can clear its slot in _ownedTokensIndex to trigger a gas refund
_ownedTokensIndex[tokenId] = 0;
_removeTokenFromAllTokensEnumeration(tokenId);
}
/**
* @dev Gets the list of token IDs of the requested owner.
* @param owner address owning the tokens
* @return uint256[] List of token IDs owned by the requested address
*/
function _tokensOfOwner(address owner)
internal
view
returns (uint256[] storage)
{
return _ownedTokens[owner];
}
/**
* @dev Private function to add a token to this extension's ownership-tracking data structures.
* @param to address representing the new owner of the given token ID
* @param tokenId uint256 ID of the token to be added to the tokens list of the given address
*/
function _addTokenToOwnerEnumeration(address to, uint256 tokenId) private {
_ownedTokensIndex[tokenId] = _ownedTokens[to].length;
_ownedTokens[to].push(tokenId);
}
/**
* @dev Private function to add a token to this extension's token tracking data structures.
* @param tokenId uint256 ID of the token to be added to the tokens list
*/
function _addTokenToAllTokensEnumeration(uint256 tokenId) private {
_allTokensIndex[tokenId] = _allTokens.length;
_allTokens.push(tokenId);
}
/**
* @dev Private function to remove a token from this extension's ownership-tracking data structures. Note that
* while the token is not assigned a new owner, the `_ownedTokensIndex` mapping is _not_ updated: this allows for
* gas optimizations e.g. when performing a transfer operation (avoiding double writes).
* This has O(1) time complexity, but alters the order of the _ownedTokens array.
* @param from address representing the previous owner of the given token ID
* @param tokenId uint256 ID of the token to be removed from the tokens list of the given address
*/
function _removeTokenFromOwnerEnumeration(address from, uint256 tokenId)
private
{
// To prevent a gap in from's tokens array, we store the last token in the index of the token to delete, and
// then delete the last slot (swap and pop).
uint256 lastTokenIndex = _ownedTokens[from].length.sub(1);
uint256 tokenIndex = _ownedTokensIndex[tokenId];
// When the token to delete is the last token, the swap operation is unnecessary
if (tokenIndex != lastTokenIndex) {
uint256 lastTokenId = _ownedTokens[from][lastTokenIndex];
_ownedTokens[from][tokenIndex] = lastTokenId; // Move the last token to the slot of the to-delete token
_ownedTokensIndex[lastTokenId] = tokenIndex; // Update the moved token's index
}
// This also deletes the contents at the last position of the array
_ownedTokens[from].length--;
// Note that _ownedTokensIndex[tokenId] hasn't been cleared: it still points to the old slot (now occupied by
// lastTokenId, or just over the end of the array if the token was the last one).
}
/**
* @dev Private function to remove a token from this extension's token tracking data structures.
* This has O(1) time complexity, but alters the order of the _allTokens array.
* @param tokenId uint256 ID of the token to be removed from the tokens list
*/
function _removeTokenFromAllTokensEnumeration(uint256 tokenId) private {
// To prevent a gap in the tokens array, we store the last token in the index of the token to delete, and
// then delete the last slot (swap and pop).
uint256 lastTokenIndex = _allTokens.length.sub(1);
uint256 tokenIndex = _allTokensIndex[tokenId];
// When the token to delete is the last token, the swap operation is unnecessary. However, since this occurs so
// rarely (when the last minted token is burnt) that we still do the swap here to avoid the gas cost of adding
// an 'if' statement (like in _removeTokenFromOwnerEnumeration)
uint256 lastTokenId = _allTokens[lastTokenIndex];
_allTokens[tokenIndex] = lastTokenId; // Move the last token to the slot of the to-delete token
_allTokensIndex[lastTokenId] = tokenIndex; // Update the moved token's index
// This also deletes the contents at the last position of the array
_allTokens.length--;
_allTokensIndex[tokenId] = 0;
}
}
// File openzeppelin-solidity/contracts/token/ERC721/[email protected]
pragma solidity ^0.5.0;
/**
* @title ERC-721 Non-Fungible Token Standard, optional metadata extension
* @dev See https://eips.ethereum.org/EIPS/eip-721
*/
contract IERC721Metadata is IERC721 {
function name() external view returns (string memory);
function symbol() external view returns (string memory);
function tokenURI(uint256 tokenId) external view returns (string memory);
}
// File openzeppelin-solidity/contracts/token/ERC721/[email protected]
pragma solidity ^0.5.0;
contract ERC721Metadata is Context, ERC165, ERC721, IERC721Metadata {
// Token name
string private _name;
// Token symbol
string private _symbol;
// Base URI
string private _baseURI;
// Optional mapping for token URIs
mapping(uint256 => string) private _tokenURIs;
/*
* 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;
/**
* @dev Constructor function
*/
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_METADATA);
}
/**
* @dev Gets the token name.
* @return string representing the token name
*/
function name() external view returns (string memory) {
return _name;
}
/**
* @dev Gets the token symbol.
* @return string representing the token symbol
*/
function symbol() external view returns (string memory) {
return _symbol;
}
/**
* @dev Returns the URI for a given token ID. May return an empty string.
*
* If the token's URI is non-empty and a base URI was set (via
* {_setBaseURI}), it will be added to the token ID's URI as a prefix.
*
* Reverts if the token ID does not exist.
*/
function tokenURI(uint256 tokenId) external view returns (string memory) {
require(
_exists(tokenId),
"ERC721Metadata: URI query for nonexistent token"
);
string memory _tokenURI = _tokenURIs[tokenId];
// Even if there is a base URI, it is only appended to non-empty token-specific URIs
if (bytes(_tokenURI).length == 0) {
return "";
} else {
// abi.encodePacked is being used to concatenate strings
return string(abi.encodePacked(_baseURI, _tokenURI));
}
}
/**
* @dev Internal function to set the token URI for a given token.
*
* Reverts if the token ID does not exist.
*
* TIP: if all token IDs share a prefix (e.g. if your URIs look like
* `http://api.myproject.com/token/<id>`), use {_setBaseURI} to store
* it and save gas.
*/
function _setTokenURI(uint256 tokenId, string memory _tokenURI) internal {
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}.
*
* _Available since v2.5.0._
*/
function _setBaseURI(string memory baseURI) internal {
_baseURI = baseURI;
}
/**
* @dev Returns the base URI set via {_setBaseURI}. This will be
* automatically added as a preffix in {tokenURI} to each token's URI, when
* they are non-empty.
*
* _Available since v2.5.0._
*/
function baseURI() external view returns (string memory) {
return _baseURI;
}
/**
* @dev Internal function to burn a specific token.
* Reverts if the token does not exist.
* Deprecated, use _burn(uint256) instead.
* @param owner owner of the token to burn
* @param tokenId uint256 ID of the token being burned by the msg.sender
*/
function _burn(address owner, uint256 tokenId) internal {
super._burn(owner, tokenId);
// Clear metadata (if any)
if (bytes(_tokenURIs[tokenId]).length != 0) {
delete _tokenURIs[tokenId];
}
}
}
// File openzeppelin-solidity/contracts/token/ERC721/[email protected]
pragma solidity ^0.5.0;
/**
* @title Full ERC721 Token
* @dev This implementation includes all the required and some optional functionality of the ERC721 standard
* Moreover, it includes approve all functionality using operator terminology.
*
* See https://eips.ethereum.org/EIPS/eip-721
*/
contract ERC721Full is ERC721, ERC721Enumerable, ERC721Metadata {
constructor(string memory name, string memory symbol)
public
ERC721Metadata(name, symbol)
{
// solhint-disable-previous-line no-empty-blocks
}
}
// File openzeppelin-solidity/contracts/token/ERC20/[email protected]
pragma solidity ^0.5.0;
/**
* @dev Interface of the ERC20 standard as defined in the EIP. Does not include
* the optional functions; to access them see {ERC20Detailed}.
*/
interface IERC20 {
/**
* @dev Returns the amount of tokens in existence.
*/
function totalSupply() external view returns (uint256);
/**
* @dev Returns the amount of tokens owned by `account`.
*/
function balanceOf(address account) external view returns (uint256);
/**
* @dev Moves `amount` tokens from the caller's account to `recipient`.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transfer(address recipient, uint256 amount)
external
returns (bool);
/**
* @dev Returns the remaining number of tokens that `spender` will be
* allowed to spend on behalf of `owner` through {transferFrom}. This is
* zero by default.
*
* This value changes when {approve} or {transferFrom} are called.
*/
function allowance(address owner, address spender)
external
view
returns (uint256);
/**
* @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* IMPORTANT: Beware that changing an allowance with this method brings the risk
* that someone may use both the old and the new allowance by unfortunate
* transaction ordering. One possible solution to mitigate this race
* condition is to first reduce the spender's allowance to 0 and set the
* desired value afterwards:
* https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
*
* Emits an {Approval} event.
*/
function approve(address spender, uint256 amount) external returns (bool);
/**
* @dev Moves `amount` tokens from `sender` to `recipient` using the
* allowance mechanism. `amount` is then deducted from the caller's
* allowance.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transferFrom(
address sender,
address recipient,
uint256 amount
) external returns (bool);
/**
* @dev Emitted when `value` tokens are moved from one account (`from`) to
* another (`to`).
*
* Note that `value` may be zero.
*/
event Transfer(address indexed from, address indexed to, uint256 value);
/**
* @dev Emitted when the allowance of a `spender` for an `owner` is set by
* a call to {approve}. `value` is the new allowance.
*/
event Approval(
address indexed owner,
address indexed spender,
uint256 value
);
}
// File openzeppelin-solidity/contracts/ownership/[email protected]
pragma solidity ^0.5.0;
/**
* @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.
*
* 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.
*/
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 returns (address) {
return _owner;
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
require(isOwner(), "Ownable: caller is not the owner");
_;
}
/**
* @dev Returns true if the caller is the current owner.
*/
function isOwner() public view returns (bool) {
return _msgSender() == _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 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 onlyOwner {
_transferOwnership(newOwner);
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
*/
function _transferOwnership(address newOwner) internal {
require(
newOwner != address(0),
"Ownable: new owner is the zero address"
);
emit OwnershipTransferred(_owner, newOwner);
_owner = newOwner;
}
}
// File openzeppelin-solidity/contracts/access/[email protected]
pragma solidity ^0.5.0;
/**
* @title Roles
* @dev Library for managing addresses assigned to a Role.
*/
library Roles {
struct Role {
mapping(address => bool) bearer;
}
/**
* @dev Give an account access to this role.
*/
function add(Role storage role, address account) internal {
require(!has(role, account), "Roles: account already has role");
role.bearer[account] = true;
}
/**
* @dev Remove an account's access to this role.
*/
function remove(Role storage role, address account) internal {
require(has(role, account), "Roles: account does not have role");
role.bearer[account] = false;
}
/**
* @dev Check if an account has this role.
* @return bool
*/
function has(Role storage role, address account)
internal
view
returns (bool)
{
require(account != address(0), "Roles: account is the zero address");
return role.bearer[account];
}
}
// File contracts/helpers/strings.sol
/*
* @title String & slice utility library for Solidity contracts.
* @author Nick Johnson <[email protected]>
*/
pragma solidity ^0.5.0;
library strings {
struct slice {
uint256 _len;
uint256 _ptr;
}
function memcpy(
uint256 dest,
uint256 src,
uint256 len
) private pure {
// Copy word-length chunks while possible
for (; len >= 32; len -= 32) {
assembly {
mstore(dest, mload(src))
}
dest += 32;
src += 32;
}
// Copy remaining bytes
uint256 mask = 256**(32 - len) - 1;
assembly {
let srcpart := and(mload(src), not(mask))
let destpart := and(mload(dest), mask)
mstore(dest, or(destpart, srcpart))
}
}
/*
* @dev Returns a slice containing the entire string.
* @param self The string to make a slice from.
* @return A newly allocated slice containing the entire string.
*/
function toSlice(string memory self) internal pure returns (slice memory) {
uint256 ptr;
assembly {
ptr := add(self, 0x20)
}
return slice(bytes(self).length, ptr);
}
/*
* @dev Returns a newly allocated string containing the concatenation of
* `self` and `other`.
* @param self The first slice to concatenate.
* @param other The second slice to concatenate.
* @return The concatenation of the two strings.
*/
function concat(slice memory self, slice memory other)
internal
pure
returns (string memory)
{
string memory ret = new string(self._len + other._len);
uint256 retptr;
assembly {
retptr := add(ret, 32)
}
memcpy(retptr, self._ptr, self._len);
memcpy(retptr + self._len, other._ptr, other._len);
return ret;
}
}
// File contracts/Metadata.sol
/**
* __ ______
* / /__ / __/ /_
* / / _ \/ /_/ __/
* / / __/ __/ /_____
* /_/\___/_/__\__/ / /__ _______ __
* / __ `/ __ `/ / / _ \/ ___/ / / /
* / /_/ / /_/ / / / __/ / / /_/ /
* \__, /\__,_/_/_/\___/_/ \__, /
* /____/ /____/
*
* https://github.com/left-gallery/contracts/
*
* Forked from folia-app/folia-contracts: https://github.com/folia-app/folia-contracts
* Many thanks to Billy Rennekamp <https://github.com/okwme> and Folia <https://www.folia.app/> 💚
*/
pragma solidity ^0.5.0;
/**
* Metadata contract is upgradeable and returns metadata about Token
*/
contract Metadata {
using strings for *;
function tokenURI(uint256 _tokenId)
public
pure
returns (string memory _infoUrl)
{
string memory base = "https://left.gallery/v1/metadata/";
string memory id = uint2str(_tokenId);
return base.toSlice().concat(id.toSlice());
}
function uint2str(uint256 i) internal pure returns (string memory) {
if (i == 0) return "0";
uint256 j = i;
uint256 length;
while (j != 0) {
length++;
j /= 10;
}
bytes memory bstr = new bytes(length);
uint256 k = length - 1;
while (i != 0) {
uint256 _uint = 48 + (i % 10);
bstr[k--] = toBytes(_uint)[31];
i /= 10;
}
return string(bstr);
}
function toBytes(uint256 x) public pure returns (bytes memory b) {
b = new bytes(32);
assembly {
mstore(add(b, 32), x)
}
}
}
// File contracts/LeftGallery.sol
/**
* __ ______
* / /__ / __/ /_
* / / _ \/ /_/ __/
* / / __/ __/ /_____
* /_/\___/_/__\__/ / /__ _______ __
* / __ `/ __ `/ / / _ \/ ___/ / / /
* / /_/ / /_/ / / / __/ / / /_/ /
* \__, /\__,_/_/_/\___/_/ \__, /
* /____/ /____/
*
* https://github.com/left-gallery/contracts/
*
* Forked from folia-app/folia-contracts: https://github.com/folia-app/folia-contracts
* Many thanks to Billy Rennekamp <https://github.com/okwme> and Folia <https://www.folia.app/> 💚
*/
pragma solidity ^0.5.0;
/**
* The Token contract does this and that...
*/
contract LeftGallery is ERC721Full, Ownable {
using Roles for Roles.Role;
Roles.Role private _admins;
uint8 admins;
address public metadata;
address public controller;
modifier onlyAdminOrController() {
require(
(_admins.has(msg.sender) || msg.sender == controller),
"DOES_NOT_HAVE_ADMIN_OR_CONTROLLER_ROLE"
);
_;
}
constructor(
string memory name,
string memory symbol,
address _metadata
) public ERC721Full(name, symbol) {
metadata = _metadata;
_admins.add(msg.sender);
admins += 1;
}
function mint(address recepient, uint256 tokenId)
public
onlyAdminOrController
{
_mint(recepient, tokenId);
}
function burn(uint256 tokenId) public onlyAdminOrController {
_burn(ownerOf(tokenId), tokenId);
}
function updateMetadata(address _metadata) public onlyAdminOrController {
metadata = _metadata;
}
function updateController(address _controller)
public
onlyAdminOrController
{
controller = _controller;
}
function addAdmin(address _admin) public onlyOwner {
_admins.add(_admin);
admins += 1;
}
function removeAdmin(address _admin) public onlyOwner {
require(admins > 1, "CANT_REMOVE_LAST_ADMIN");
_admins.remove(_admin);
admins -= 1;
}
function tokenURI(uint256 _tokenId)
external
view
returns (string memory _infoUrl)
{
return Metadata(metadata).tokenURI(_tokenId);
}
/**
* @dev Moves Token to a certain address.
* @param _to The address to receive the Token.
* @param _amount The amount of Token to be transferred.
* @param _token The address of the Token to be transferred.
*/
function moveToken(
address _to,
uint256 _amount,
address _token
) public onlyAdminOrController returns (bool) {
require(_amount <= IERC20(_token).balanceOf(address(this)));
return IERC20(_token).transfer(_to, _amount);
}
}