// File contracts/libs/IERC165.sol

// File: openzeppelin-solidity/contracts/introspection/IERC165.sol
pragma solidity ^0.5.0;

/**
 * @dev Interface of the ERC165 standard, as defined in the
 * [EIP](https://eips.ethereum.org/EIPS/eip-165).
 *
 * 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
     * [EIP section](https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified)
     * 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 contracts/libs/ERC165.sol

// File: openzeppelin-solidity/contracts/introspection/ERC165.sol

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 contracts/libs/IERC721.sol

// File: openzeppelin-solidity/contracts/token/ERC721/IERC721.sol

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 `setApproveForAll`.
     */
    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 `setApproveForAll`.
     */
    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 contracts/libs/SafeMath.sol

// File: openzeppelin-solidity/contracts/math/SafeMath.sol

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) {
        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;
    }
}


// File contracts/libs/Address.sol

// File: openzeppelin-solidity/contracts/utils/Address.sol

pragma solidity ^0.5.0;

/**
 * @dev Collection of functions related to the address type,
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * This test is non-exhaustive, and there may be false-negatives: during the
     * execution of a contract's constructor, its address will be reported as
     * not containing a contract.
     *
     * > It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies in 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;
    }
}


// File contracts/libs/Counters.sol

// File: openzeppelin-solidity/contracts/drafts/Counters.sol

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 {
        counter._value += 1;
    }

    function decrement(Counter storage counter) internal {
        counter._value = counter._value.sub(1);
    }
}


// File contracts/libs/IERC721Receiver.sol

// File: openzeppelin-solidity/contracts/token/ERC721/IERC721Receiver.sol

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 {
    function onERC721Received(address operator, address from, uint256 tokenId, bytes memory data)
    public returns (bytes4);
}


// File contracts/libs/ERC721.sol

// File: openzeppelin-solidity/contracts/token/ERC721/ERC721.sol

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 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 private constant _INTERFACE_ID_ERC721 = 0x80ac58cd;

    constructor () public {
        // register the supported interfaces to conform to ERC721 via ERC165
        _registerInterface(_INTERFACE_ID_ERC721);
    }


    function balanceOf(address owner) public view returns (uint256) {
        require(owner != address(0), "ERC721: balance query for the zero address");

        return _ownedTokensCount[owner].current();
    }

    function ownerOf(uint256 tokenId) public view returns (address) {
        address owner = _tokenOwner[tokenId];
        require(owner != address(0), "ERC721: owner query for nonexistent token");

        return owner;
    }

    function approve(address to, uint256 tokenId) public {
        address owner = ownerOf(tokenId);
        require(to != owner, "ERC721: approval to current owner");

        require(msg.sender == owner || isApprovedForAll(owner, msg.sender),
            "ERC721: approve caller is not owner nor approved for all"
        );

        _tokenApprovals[tokenId] = to;
        emit Approval(owner, to, tokenId);
    }

    function getApproved(uint256 tokenId) public view returns (address) {
        require(_exists(tokenId), "ERC721: approved query for nonexistent token");

        return _tokenApprovals[tokenId];
    }

    function setApprovalForAll(address to, bool approved) public {
        require(to != msg.sender, "ERC721: approve to caller");

        _operatorApprovals[msg.sender][to] = approved;
        emit ApprovalForAll(msg.sender, to, approved);
    }

    function isApprovedForAll(address owner, address operator) public view returns (bool) {
        return _operatorApprovals[owner][operator];
    }

    function transferFrom(address from, address to, uint256 tokenId) public {
        //solhint-disable-next-line max-line-length
        require(_isApprovedOrOwner(msg.sender, tokenId), "ERC721: transfer caller is not owner nor approved");

        _transferFrom(from, to, tokenId);
    }

    function safeTransferFrom(address from, address to, uint256 tokenId) public {
        safeTransferFrom(from, to, tokenId, "");
    }

    function safeTransferFrom(address from, address to, uint256 tokenId, bytes memory _data) public {
        transferFrom(from, to, tokenId);
        require(_checkOnERC721Received(from, to, tokenId, _data), "ERC721: transfer to non ERC721Receiver implementer");
    }

    function _exists(uint256 tokenId) internal view returns (bool) {
        address owner = _tokenOwner[tokenId];
        return owner != address(0);
    }

    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));
    }

    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);
    }

    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);
    }

    function _burn(uint256 tokenId) internal {
        _burn(ownerOf(tokenId), tokenId);
    }

    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);
    }

    function _checkOnERC721Received(address from, address to, uint256 tokenId, bytes memory _data)
    internal returns (bool)
    {
        if (!to.isContract()) {
            return true;
        }

        bytes4 retval = IERC721Receiver(to).onERC721Received(msg.sender, from, tokenId, _data);
        return (retval == _ERC721_RECEIVED);
    }

    function _clearApproval(uint256 tokenId) private {
        if (_tokenApprovals[tokenId] != address(0)) {
            _tokenApprovals[tokenId] = address(0);
        }
    }
}


// File contracts/libs/IERC721Enumerable.sol

// File: openzeppelin-solidity/contracts/token/ERC721/IERC721Enumerable.sol

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 contracts/libs/ERC721Enumerable.sol

// File: openzeppelin-solidity/contracts/token/ERC721/ERC721Enumerable.sol

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 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 _burn(uint256) 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 contracts/libs/CustomERC721Metadata.sol

// File: contracts/CustomERC721Metadata.sol

pragma solidity ^0.5.0;






/**
 * ERC721 base contract without the concept of tokenUri as this is managed by the parent
 */
contract CustomERC721Metadata is ERC165, ERC721, ERC721Enumerable {

    // Token name
    string private _name;

    // Token symbol
    string private _symbol;

    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;
    }

}


// File contracts/libs/Strings.sol

// File: contracts/Strings.sol

pragma solidity ^0.5.0;

//https://github.com/oraclize/ethereum-api/blob/master/oraclizeAPI_0.5.sol
library Strings {

    function strConcat(string memory _a, string memory _b) internal pure returns (string memory _concatenatedString) {
        return strConcat(_a, _b, "", "", "");
    }

    function strConcat(string memory _a, string memory _b, string memory _c) internal pure returns (string memory _concatenatedString) {
        return strConcat(_a, _b, _c, "", "");
    }

    function strConcat(string memory _a, string memory _b, string memory _c, string memory _d) internal pure returns (string memory _concatenatedString) {
        return strConcat(_a, _b, _c, _d, "");
    }

    function strConcat(string memory _a, string memory _b, string memory _c, string memory _d, string memory _e) internal pure returns (string memory _concatenatedString) {
        bytes memory _ba = bytes(_a);
        bytes memory _bb = bytes(_b);
        bytes memory _bc = bytes(_c);
        bytes memory _bd = bytes(_d);
        bytes memory _be = bytes(_e);
        string memory abcde = new string(_ba.length + _bb.length + _bc.length + _bd.length + _be.length);
        bytes memory babcde = bytes(abcde);
        uint k = 0;
        uint i = 0;
        for (i = 0; i < _ba.length; i++) {
            babcde[k++] = _ba[i];
        }
        for (i = 0; i < _bb.length; i++) {
            babcde[k++] = _bb[i];
        }
        for (i = 0; i < _bc.length; i++) {
            babcde[k++] = _bc[i];
        }
        for (i = 0; i < _bd.length; i++) {
            babcde[k++] = _bd[i];
        }
        for (i = 0; i < _be.length; i++) {
            babcde[k++] = _be[i];
        }
        return string(babcde);
    }

    function uint2str(uint _i) internal pure returns (string memory _uintAsString) {
        if (_i == 0) {
            return "0";
        }
        uint j = _i;
        uint len;
        while (j != 0) {
            len++;
            j /= 10;
        }
        bytes memory bstr = new bytes(len);
        uint k = len - 1;
        while (_i != 0) {
            bstr[k--] = byte(uint8(48 + _i % 10));
            _i /= 10;
        }
        return string(bstr);
    }
}


// File contracts/GenArt721Core.sol

// File: contracts/GenArt721Core.sol

//0x1454EFCa69FA654e5A7d83CB61c1aD81790c44B7

//https://oneclickdapp.com/radar-valery/

pragma solidity ^0.5.0;




interface Randomizer {
   function returnValue() external view returns(bytes32);
}

contract GenArt721Core is CustomERC721Metadata {
    using SafeMath for uint256;

    event Mint(
        address indexed _to,
        uint256 indexed _tokenId,
        uint256 indexed _projectId

    );

    Randomizer public randomizerContract;

    struct Project {
        string name;
        string artist;
        string description;
        string website;
        string license;
        bool dynamic;
        string projectBaseURI;
        string projectBaseIpfsURI;
        uint256 invocations;
        uint256 maxInvocations;
        string scriptJSON;
        mapping(uint256 => string) scripts;
        uint scriptCount;
        string ipfsHash;
        bool useHashString;
        bool useIpfs;
        bool active;
        bool locked;
        bool paused;

    }

    uint256 constant ONE_MILLION = 1_000_000;
    mapping(uint256 => Project) projects;

    //All financial functions are stripped from struct for visibility
    mapping(uint256 => address) public projectIdToArtistAddress;
    mapping(uint256 => string) public projectIdToCurrencySymbol;
    mapping(uint256 => address) public projectIdToCurrencyAddress;
    mapping(uint256 => uint256) public projectIdToPricePerTokenInWei;
    mapping(uint256 => address) public projectIdToAdditionalPayee;
    mapping(uint256 => uint256) public projectIdToAdditionalPayeePercentage;
    mapping(uint256 => uint256) public projectIdToSecondaryMarketRoyaltyPercentage;

    address public artblocksAddress;
    uint256 public artblocksPercentage = 10;

    mapping(uint256 => string) public staticIpfsImageLink;
    mapping(uint256 => uint256) public tokenIdToProjectId;
    mapping(uint256 => uint256[]) internal projectIdToTokenIds;
    mapping(uint256 => bytes32) public tokenIdToHash;
    mapping(bytes32 => uint256) public hashToTokenId;

    address public admin;
    mapping(address => bool) public isWhitelisted;
    mapping(address => bool) public isMintWhitelisted;

    uint256 public nextProjectId = 3;

    modifier onlyValidTokenId(uint256 _tokenId) {
        require(_exists(_tokenId), "Token ID does not exist");
        _;
    }

    modifier onlyUnlocked(uint256 _projectId) {
        require(!projects[_projectId].locked, "Only if unlocked");
        _;
    }

    modifier onlyArtist(uint256 _projectId) {
        require(msg.sender == projectIdToArtistAddress[_projectId], "Only artist");
        _;
    }

    modifier onlyAdmin() {
        require(msg.sender == admin, "Only admin");
        _;
    }

    modifier onlyWhitelisted() {
        require(isWhitelisted[msg.sender], "Only whitelisted");
        _;
    }

    modifier onlyArtistOrWhitelisted(uint256 _projectId) {
        require(isWhitelisted[msg.sender] || msg.sender == projectIdToArtistAddress[_projectId], "Only artist or whitelisted");
        _;
    }

    constructor(string memory _tokenName, string memory _tokenSymbol, address _randomizerContract) CustomERC721Metadata(_tokenName, _tokenSymbol) public {
        admin = msg.sender;
        isWhitelisted[msg.sender] = true;
        artblocksAddress = msg.sender;
        randomizerContract = Randomizer(_randomizerContract);

    }

    function mint(address _to, uint256 _projectId, address _by) external returns (uint256 _tokenId) {
        require(isMintWhitelisted[msg.sender], "Must mint from whitelisted minter contract.");
        require(projects[_projectId].invocations.add(1) <= projects[_projectId].maxInvocations, "Must not exceed max invocations");
        require(projects[_projectId].active || _by == projectIdToArtistAddress[_projectId], "Project must exist and be active");
        require(!projects[_projectId].paused || _by == projectIdToArtistAddress[_projectId], "Purchases are paused.");


        uint256 tokenId = _mintToken(_to, _projectId);

        return tokenId;
    }

    function _mintToken(address _to, uint256 _projectId) internal returns (uint256 _tokenId) {

        uint256 tokenIdToBe = (_projectId * ONE_MILLION) + projects[_projectId].invocations;

        projects[_projectId].invocations = projects[_projectId].invocations.add(1);


            bytes32 hash = keccak256(abi.encodePacked(projects[_projectId].invocations, block.number, blockhash(block.number - 1), msg.sender, randomizerContract.returnValue()));
            tokenIdToHash[tokenIdToBe]=hash;
            hashToTokenId[hash] = tokenIdToBe;


        _mint(_to, tokenIdToBe);

        tokenIdToProjectId[tokenIdToBe] = _projectId;
        projectIdToTokenIds[_projectId].push(tokenIdToBe);

        emit Mint(_to, tokenIdToBe, _projectId);

        return tokenIdToBe;
    }
    function updateArtblocksAddress(address _artblocksAddress) public onlyAdmin {
        artblocksAddress = _artblocksAddress;
    }

    function updateArtblocksPercentage(uint256 _artblocksPercentage) public onlyAdmin {
        require(_artblocksPercentage <= 25, "Max of 25%");
        artblocksPercentage = _artblocksPercentage;
    }

    function addWhitelisted(address _address) public onlyAdmin {
        isWhitelisted[_address] = true;
    }

    function removeWhitelisted(address _address) public onlyAdmin {
        isWhitelisted[_address] = false;
    }

    function addMintWhitelisted(address _address) public onlyAdmin {
        isMintWhitelisted[_address] = true;
    }

    function removeMintWhitelisted(address _address) public onlyAdmin {
        isMintWhitelisted[_address] = false;
    }

    function updateRandomizerAddress(address _randomizerAddress) public onlyWhitelisted {
      randomizerContract = Randomizer(_randomizerAddress);
    }
    function toggleProjectIsLocked(uint256 _projectId) public onlyWhitelisted onlyUnlocked(_projectId) {
        projects[_projectId].locked = true;
    }

    function toggleProjectIsActive(uint256 _projectId) public onlyWhitelisted {
        projects[_projectId].active = !projects[_projectId].active;
    }

    function updateProjectArtistAddress(uint256 _projectId, address _artistAddress) public onlyArtistOrWhitelisted(_projectId) {
        projectIdToArtistAddress[_projectId] = _artistAddress;
    }

    function toggleProjectIsPaused(uint256 _projectId) public onlyArtist(_projectId) {
        projects[_projectId].paused = !projects[_projectId].paused;
    }

    function addProject(string memory _projectName, address _artistAddress, uint256 _pricePerTokenInWei, bool _dynamic) public onlyWhitelisted {

        uint256 projectId = nextProjectId;
        projectIdToArtistAddress[projectId] = _artistAddress;
        projects[projectId].name = _projectName;
        projectIdToCurrencySymbol[projectId] = "ETH";
        projectIdToPricePerTokenInWei[projectId] = _pricePerTokenInWei;
        projects[projectId].paused=true;
        projects[projectId].dynamic=_dynamic;
        projects[projectId].maxInvocations = ONE_MILLION;
        if (!_dynamic) {
            projects[projectId].useHashString = false;
        } else {
            projects[projectId].useHashString = true;
        }
        nextProjectId = nextProjectId.add(1);
    }

    function updateProjectCurrencyInfo(uint256 _projectId, string memory _currencySymbol, address _currencyAddress) onlyArtist(_projectId) public {
        projectIdToCurrencySymbol[_projectId] = _currencySymbol;
        projectIdToCurrencyAddress[_projectId] = _currencyAddress;
    }

    function updateProjectPricePerTokenInWei(uint256 _projectId, uint256 _pricePerTokenInWei) onlyArtist(_projectId) public {
        projectIdToPricePerTokenInWei[_projectId] = _pricePerTokenInWei;
    }

    function updateProjectName(uint256 _projectId, string memory _projectName) onlyUnlocked(_projectId) onlyArtistOrWhitelisted(_projectId) public {
        projects[_projectId].name = _projectName;
    }

    function updateProjectArtistName(uint256 _projectId, string memory _projectArtistName) onlyUnlocked(_projectId) onlyArtistOrWhitelisted(_projectId) public {
        projects[_projectId].artist = _projectArtistName;
    }

    function updateProjectAdditionalPayeeInfo(uint256 _projectId, address _additionalPayee, uint256 _additionalPayeePercentage) onlyArtist(_projectId) public {
        require(_additionalPayeePercentage <= 100, "Max of 100%");
        projectIdToAdditionalPayee[_projectId] = _additionalPayee;
        projectIdToAdditionalPayeePercentage[_projectId] = _additionalPayeePercentage;
    }

    function updateProjectSecondaryMarketRoyaltyPercentage(uint256 _projectId, uint256 _secondMarketRoyalty) onlyArtist(_projectId) public {
        require(_secondMarketRoyalty <= 100, "Max of 100%");
        projectIdToSecondaryMarketRoyaltyPercentage[_projectId] = _secondMarketRoyalty;
    }

    function updateProjectDescription(uint256 _projectId, string memory _projectDescription) onlyArtist(_projectId) public {
        projects[_projectId].description = _projectDescription;
    }

    function updateProjectWebsite(uint256 _projectId, string memory _projectWebsite) onlyArtist(_projectId) public {
        projects[_projectId].website = _projectWebsite;
    }

    function updateProjectLicense(uint256 _projectId, string memory _projectLicense) onlyUnlocked(_projectId) onlyArtistOrWhitelisted(_projectId) public {
        projects[_projectId].license = _projectLicense;
    }

    function updateProjectMaxInvocations(uint256 _projectId, uint256 _maxInvocations) onlyArtist(_projectId) public {
        require((!projects[_projectId].locked || _maxInvocations<projects[_projectId].maxInvocations), "Only if unlocked");
        require(_maxInvocations > projects[_projectId].invocations, "You must set max invocations greater than current invocations");
        require(_maxInvocations <= ONE_MILLION, "Cannot exceed 1,000,000");
        projects[_projectId].maxInvocations = _maxInvocations;
    }

    function toggleProjectUseHashString(uint256 _projectId) onlyUnlocked(_projectId) onlyArtistOrWhitelisted(_projectId) public {
      require(projects[_projectId].invocations == 0, "Cannot modify after a token is minted.");
      projects[_projectId].useHashString = !projects[_projectId].useHashString;
    }

    function addProjectScript(uint256 _projectId, string memory _script) onlyUnlocked(_projectId) onlyArtistOrWhitelisted(_projectId) public {
        projects[_projectId].scripts[projects[_projectId].scriptCount] = _script;
        projects[_projectId].scriptCount = projects[_projectId].scriptCount.add(1);
    }

    function updateProjectScript(uint256 _projectId, uint256 _scriptId, string memory _script) onlyUnlocked(_projectId) onlyArtistOrWhitelisted(_projectId) public {
        require(_scriptId < projects[_projectId].scriptCount, "scriptId out of range");
        projects[_projectId].scripts[_scriptId] = _script;
    }

    function removeProjectLastScript(uint256 _projectId) onlyUnlocked(_projectId) onlyArtistOrWhitelisted(_projectId) public {
        require(projects[_projectId].scriptCount > 0, "there are no scripts to remove");
        delete projects[_projectId].scripts[projects[_projectId].scriptCount - 1];
        projects[_projectId].scriptCount = projects[_projectId].scriptCount.sub(1);
    }

    function updateProjectScriptJSON(uint256 _projectId, string memory _projectScriptJSON) onlyUnlocked(_projectId) onlyArtistOrWhitelisted(_projectId) public {
        projects[_projectId].scriptJSON = _projectScriptJSON;
    }

    function updateProjectIpfsHash(uint256 _projectId, string memory _ipfsHash) onlyUnlocked(_projectId) onlyArtistOrWhitelisted(_projectId) public {
        projects[_projectId].ipfsHash = _ipfsHash;
    }

    function updateProjectBaseURI(uint256 _projectId, string memory _newBaseURI) onlyArtist(_projectId) public {
        projects[_projectId].projectBaseURI = _newBaseURI;
    }

    function updateProjectBaseIpfsURI(uint256 _projectId, string memory _projectBaseIpfsURI) onlyArtist(_projectId) public {
        projects[_projectId].projectBaseIpfsURI = _projectBaseIpfsURI;
    }

    function toggleProjectUseIpfsForStatic(uint256 _projectId) onlyArtist(_projectId) public {
        require(!projects[_projectId].dynamic, "can only set static IPFS hash for static projects");
        projects[_projectId].useIpfs = !projects[_projectId].useIpfs;
    }

    function toggleProjectIsDynamic(uint256 _projectId) onlyUnlocked(_projectId) onlyArtistOrWhitelisted(_projectId) public {
      require(projects[_projectId].invocations == 0, "Can not switch after a token is minted.");
        if (projects[_projectId].dynamic) {
            projects[_projectId].useHashString = false;
        } else {
            projects[_projectId].useHashString = true;
        }
        projects[_projectId].dynamic = !projects[_projectId].dynamic;
    }

    function overrideTokenDynamicImageWithIpfsLink(uint256 _tokenId, string memory _ipfsHash) onlyArtist(tokenIdToProjectId[_tokenId]) public {
        staticIpfsImageLink[_tokenId] = _ipfsHash;
    }

    function clearTokenIpfsImageUri(uint256 _tokenId) onlyArtist(tokenIdToProjectId[_tokenId]) public {
        delete staticIpfsImageLink[tokenIdToProjectId[_tokenId]];
    }

    function projectDetails(uint256 _projectId) view public returns (string memory projectName, string memory artist, string memory description, string memory website, string memory license, bool dynamic) {
        projectName = projects[_projectId].name;
        artist = projects[_projectId].artist;
        description = projects[_projectId].description;
        website = projects[_projectId].website;
        license = projects[_projectId].license;
        dynamic = projects[_projectId].dynamic;
    }

    function projectTokenInfo(uint256 _projectId) view public returns (address artistAddress, uint256 pricePerTokenInWei, uint256 invocations, uint256 maxInvocations, bool active, address additionalPayee, uint256 additionalPayeePercentage ,string memory currency, address currencyAddress) {
        artistAddress = projectIdToArtistAddress[_projectId];
        pricePerTokenInWei = projectIdToPricePerTokenInWei[_projectId];
        invocations = projects[_projectId].invocations;
        maxInvocations = projects[_projectId].maxInvocations;
        active = projects[_projectId].active;
        additionalPayee = projectIdToAdditionalPayee[_projectId];
        additionalPayeePercentage = projectIdToAdditionalPayeePercentage[_projectId];
        currency = projectIdToCurrencySymbol[_projectId];
        currencyAddress = projectIdToCurrencyAddress[_projectId];
    }

    function projectScriptInfo(uint256 _projectId) view public returns (string memory scriptJSON, uint256 scriptCount, bool useHashString, string memory ipfsHash, bool locked, bool paused) {
        scriptJSON = projects[_projectId].scriptJSON;
        scriptCount = projects[_projectId].scriptCount;
        useHashString = projects[_projectId].useHashString;
        ipfsHash = projects[_projectId].ipfsHash;
        locked = projects[_projectId].locked;
        paused = projects[_projectId].paused;
    }

    function projectScriptByIndex(uint256 _projectId, uint256 _index) view public returns (string memory){
        return projects[_projectId].scripts[_index];
    }

    function projectURIInfo(uint256 _projectId) view public returns (string memory projectBaseURI, string memory projectBaseIpfsURI, bool useIpfs) {
        projectBaseURI = projects[_projectId].projectBaseURI;
        projectBaseIpfsURI = projects[_projectId].projectBaseIpfsURI;
        useIpfs = projects[_projectId].useIpfs;
    }

    function projectShowAllTokens(uint _projectId) public view returns (uint256[] memory){
        return projectIdToTokenIds[_projectId];
    }

    function tokensOfOwner(address owner) external view returns (uint256[] memory) {
        return _tokensOfOwner(owner);
    }

    function getRoyaltyData(uint256 _tokenId) public view returns (address artistAddress, address additionalPayee, uint256 additionalPayeePercentage, uint256 royaltyFeeByID) {
        artistAddress = projectIdToArtistAddress[tokenIdToProjectId[_tokenId]];
        additionalPayee = projectIdToAdditionalPayee[tokenIdToProjectId[_tokenId]];
        additionalPayeePercentage = projectIdToAdditionalPayeePercentage[tokenIdToProjectId[_tokenId]];
        royaltyFeeByID = projectIdToSecondaryMarketRoyaltyPercentage[tokenIdToProjectId[_tokenId]];
    }

    function tokenURI(uint256 _tokenId) external view onlyValidTokenId(_tokenId) returns (string memory) {
        if (bytes(staticIpfsImageLink[_tokenId]).length > 0) {
            return Strings.strConcat(projects[tokenIdToProjectId[_tokenId]].projectBaseIpfsURI, staticIpfsImageLink[_tokenId]);
        }

        if (!projects[tokenIdToProjectId[_tokenId]].dynamic && projects[tokenIdToProjectId[_tokenId]].useIpfs) {
            return Strings.strConcat(projects[tokenIdToProjectId[_tokenId]].projectBaseIpfsURI, projects[tokenIdToProjectId[_tokenId]].ipfsHash);
        }

        return Strings.strConcat(projects[tokenIdToProjectId[_tokenId]].projectBaseURI, Strings.uint2str(_tokenId));
    }
}

// Copyright (C) 2015, 2016, 2017 Dapphub

// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

pragma solidity ^0.4.18;

contract WETH9 {
    string public name     = "Wrapped Ether";
    string public symbol   = "WETH";
    uint8  public decimals = 18;

    event  Approval(address indexed src, address indexed guy, uint wad);
    event  Transfer(address indexed src, address indexed dst, uint wad);
    event  Deposit(address indexed dst, uint wad);
    event  Withdrawal(address indexed src, uint wad);

    mapping (address => uint)                       public  balanceOf;
    mapping (address => mapping (address => uint))  public  allowance;

    function() public payable {
        deposit();
    }
    function deposit() public payable {
        balanceOf[msg.sender] += msg.value;
        Deposit(msg.sender, msg.value);
    }
    function withdraw(uint wad) public {
        require(balanceOf[msg.sender] >= wad);
        balanceOf[msg.sender] -= wad;
        msg.sender.transfer(wad);
        Withdrawal(msg.sender, wad);
    }

    function totalSupply() public view returns (uint) {
        return this.balance;
    }

    function approve(address guy, uint wad) public returns (bool) {
        allowance[msg.sender][guy] = wad;
        Approval(msg.sender, guy, wad);
        return true;
    }

    function transfer(address dst, uint wad) public returns (bool) {
        return transferFrom(msg.sender, dst, wad);
    }

    function transferFrom(address src, address dst, uint wad)
        public
        returns (bool)
    {
        require(balanceOf[src] >= wad);

        if (src != msg.sender && allowance[src][msg.sender] != uint(-1)) {
            require(allowance[src][msg.sender] >= wad);
            allowance[src][msg.sender] -= wad;
        }

        balanceOf[src] -= wad;
        balanceOf[dst] += wad;

        Transfer(src, dst, wad);

        return true;
    }
}


/*
                    GNU GENERAL PUBLIC LICENSE
                       Version 3, 29 June 2007

 Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
 Everyone is permitted to copy and distribute verbatim copies
 of this license document, but changing it is not allowed.

                            Preamble

  The GNU General Public License is a free, copyleft license for
software and other kinds of works.

  The licenses for most software and other practical works are designed
to take away your freedom to share and change the works.  By contrast,
the GNU General Public License is intended to guarantee your freedom to
share and change all versions of a program--to make sure it remains free
software for all its users.  We, the Free Software Foundation, use the
GNU General Public License for most of our software; it applies also to
any other work released this way by its authors.  You can apply it to
your programs, too.

  When we speak of free software, we are referring to freedom, not
price.  Our General Public Licenses are designed to make sure that you
have the freedom to distribute copies of free software (and charge for
them if you wish), that you receive source code or can get it if you
want it, that you can change the software or use pieces of it in new
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  To protect your rights, we need to prevent others from denying you
these rights or asking you to surrender the rights.  Therefore, you have
certain responsibilities if you distribute copies of the software, or if
you modify it: responsibilities to respect the freedom of others.

  For example, if you distribute copies of such a program, whether
gratis or for a fee, you must pass on to the recipients the same
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  Developers that use the GNU GPL protect your rights with two steps:
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giving you legal permission to copy, distribute and/or modify it.

  For the developers' and authors' protection, the GPL clearly explains
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  Some devices are designed to deny users access to install or run
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  The precise terms and conditions for copying, distribution and
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  "This License" refers to version 3 of the GNU General Public License.

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  7. Additional Terms.

  "Additional permissions" are terms that supplement the terms of this
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Additional permissions that are applicable to the entire Program shall
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  When you convey a copy of a covered work, you may at your option
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  All other non-permissive additional terms are considered "further
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  11. Patents.

  A "contributor" is a copyright holder who authorizes use under this
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  Nothing in this License shall be construed as excluding or limiting
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  12. No Surrender of Others' Freedom.

  If conditions are imposed on you (whether by court order, agreement or
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  13. Use with the GNU Affero General Public License.

  Notwithstanding any other provision of this License, you have
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  14. Revised Versions of this License.

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  If the Program specifies that a proxy can decide which future
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  15. Disclaimer of Warranty.

  THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
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ALL NECESSARY SERVICING, REPAIR OR CORRECTION.

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  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
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DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
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EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
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  17. Interpretation of Sections 15 and 16.

  If the disclaimer of warranty and limitation of liability provided
above cannot be given local legal effect according to their terms,
reviewing courts shall apply local law that most closely approximates
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copy of the Program in return for a fee.

                     END OF TERMS AND CONDITIONS

            How to Apply These Terms to Your New Programs

  If you develop a new program, and you want it to be of the greatest
possible use to the public, the best way to achieve this is to make it
free software which everyone can redistribute and change under these terms.

  To do so, attach the following notices to the program.  It is safest
to attach them to the start of each source file to most effectively
state the exclusion of warranty; and each file should have at least
the "copyright" line and a pointer to where the full notice is found.

    <one line to give the program's name and a brief idea of what it does.>
    Copyright (C) <year>  <name of author>

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.

Also add information on how to contact you by electronic and paper mail.

  If the program does terminal interaction, make it output a short
notice like this when it starts in an interactive mode:

    <program>  Copyright (C) <year>  <name of author>
    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
    This is free software, and you are welcome to redistribute it
    under certain conditions; type `show c' for details.

The hypothetical commands `show w' and `show c' should show the appropriate
parts of the General Public License.  Of course, your program's commands
might be different; for a GUI interface, you would use an "about box".

  You should also get your employer (if you work as a programmer) or school,
if any, to sign a "copyright disclaimer" for the program, if necessary.
For more information on this, and how to apply and follow the GNU GPL, see
<http://www.gnu.org/licenses/>.

  The GNU General Public License does not permit incorporating your program
into proprietary programs.  If your program is a subroutine library, you
may consider it more useful to permit linking proprietary applications with
the library.  If this is what you want to do, use the GNU Lesser General
Public License instead of this License.  But first, please read
<http://www.gnu.org/philosophy/why-not-lgpl.html>.

*/

pragma solidity ^0.4.17;

/**
 * @title SafeMath
 * @dev Math operations with safety checks that throw on error
 */
library SafeMath {
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        if (a == 0) {
            return 0;
        }
        uint256 c = a * b;
        assert(c / a == b);
        return c;
    }

    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        // assert(b > 0); // Solidity automatically throws when dividing by 0
        uint256 c = a / b;
        // assert(a == b * c + a % b); // There is no case in which this doesn't hold
        return c;
    }

    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        assert(b <= a);
        return a - b;
    }

    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        assert(c >= a);
        return c;
    }
}

/**
 * @title Ownable
 * @dev The Ownable contract has an owner address, and provides basic authorization control
 * functions, this simplifies the implementation of "user permissions".
 */
contract Ownable {
    address public owner;

    /**
      * @dev The Ownable constructor sets the original `owner` of the contract to the sender
      * account.
      */
    function Ownable() public {
        owner = msg.sender;
    }

    /**
      * @dev Throws if called by any account other than the owner.
      */
    modifier onlyOwner() {
        require(msg.sender == owner);
        _;
    }

    /**
    * @dev Allows the current owner to transfer control of the contract to a newOwner.
    * @param newOwner The address to transfer ownership to.
    */
    function transferOwnership(address newOwner) public onlyOwner {
        if (newOwner != address(0)) {
            owner = newOwner;
        }
    }

}

/**
 * @title ERC20Basic
 * @dev Simpler version of ERC20 interface
 * @dev see https://github.com/ethereum/EIPs/issues/20
 */
contract ERC20Basic {
    uint public _totalSupply;
    function totalSupply() public constant returns (uint);
    function balanceOf(address who) public constant returns (uint);
    function transfer(address to, uint value) public;
    event Transfer(address indexed from, address indexed to, uint value);
}

/**
 * @title ERC20 interface
 * @dev see https://github.com/ethereum/EIPs/issues/20
 */
contract ERC20 is ERC20Basic {
    function allowance(address owner, address spender) public constant returns (uint);
    function transferFrom(address from, address to, uint value) public;
    function approve(address spender, uint value) public;
    event Approval(address indexed owner, address indexed spender, uint value);
}

/**
 * @title Basic token
 * @dev Basic version of StandardToken, with no allowances.
 */
contract BasicToken is Ownable, ERC20Basic {
    using SafeMath for uint;

    mapping(address => uint) public balances;

    // additional variables for use if transaction fees ever became necessary
    uint public basisPointsRate = 0;
    uint public maximumFee = 0;

    /**
    * @dev Fix for the ERC20 short address attack.
    */
    modifier onlyPayloadSize(uint size) {
        require(!(msg.data.length < size + 4));
        _;
    }

    /**
    * @dev transfer token for a specified address
    * @param _to The address to transfer to.
    * @param _value The amount to be transferred.
    */
    function transfer(address _to, uint _value) public onlyPayloadSize(2 * 32) {
        uint fee = (_value.mul(basisPointsRate)).div(10000);
        if (fee > maximumFee) {
            fee = maximumFee;
        }
        uint sendAmount = _value.sub(fee);
        balances[msg.sender] = balances[msg.sender].sub(_value);
        balances[_to] = balances[_to].add(sendAmount);
        if (fee > 0) {
            balances[owner] = balances[owner].add(fee);
            Transfer(msg.sender, owner, fee);
        }
        Transfer(msg.sender, _to, sendAmount);
    }

    /**
    * @dev Gets the balance of the specified address.
    * @param _owner The address to query the the balance of.
    * @return An uint representing the amount owned by the passed address.
    */
    function balanceOf(address _owner) public constant returns (uint balance) {
        return balances[_owner];
    }

}

/**
 * @title Standard ERC20 token
 *
 * @dev Implementation of the basic standard token.
 * @dev https://github.com/ethereum/EIPs/issues/20
 * @dev Based oncode by FirstBlood: https://github.com/Firstbloodio/token/blob/master/smart_contract/FirstBloodToken.sol
 */
contract StandardToken is BasicToken, ERC20 {

    mapping (address => mapping (address => uint)) public allowed;

    uint public constant MAX_UINT = 2**256 - 1;

    /**
    * @dev Transfer tokens from one address to another
    * @param _from address The address which you want to send tokens from
    * @param _to address The address which you want to transfer to
    * @param _value uint the amount of tokens to be transferred
    */
    function transferFrom(address _from, address _to, uint _value) public onlyPayloadSize(3 * 32) {
        var _allowance = allowed[_from][msg.sender];

        // Check is not needed because sub(_allowance, _value) will already throw if this condition is not met
        // if (_value > _allowance) throw;

        uint fee = (_value.mul(basisPointsRate)).div(10000);
        if (fee > maximumFee) {
            fee = maximumFee;
        }
        if (_allowance < MAX_UINT) {
            allowed[_from][msg.sender] = _allowance.sub(_value);
        }
        uint sendAmount = _value.sub(fee);
        balances[_from] = balances[_from].sub(_value);
        balances[_to] = balances[_to].add(sendAmount);
        if (fee > 0) {
            balances[owner] = balances[owner].add(fee);
            Transfer(_from, owner, fee);
        }
        Transfer(_from, _to, sendAmount);
    }

    /**
    * @dev Approve the passed address to spend the specified amount of tokens on behalf of msg.sender.
    * @param _spender The address which will spend the funds.
    * @param _value The amount of tokens to be spent.
    */
    function approve(address _spender, uint _value) public onlyPayloadSize(2 * 32) {

        // To change the approve amount you first have to reduce the addresses`
        //  allowance to zero by calling `approve(_spender, 0)` if it is not
        //  already 0 to mitigate the race condition described here:
        //  https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
        require(!((_value != 0) && (allowed[msg.sender][_spender] != 0)));

        allowed[msg.sender][_spender] = _value;
        Approval(msg.sender, _spender, _value);
    }

    /**
    * @dev Function to check the amount of tokens than an owner allowed to a spender.
    * @param _owner address The address which owns the funds.
    * @param _spender address The address which will spend the funds.
    * @return A uint specifying the amount of tokens still available for the spender.
    */
    function allowance(address _owner, address _spender) public constant returns (uint remaining) {
        return allowed[_owner][_spender];
    }

}


/**
 * @title Pausable
 * @dev Base contract which allows children to implement an emergency stop mechanism.
 */
contract Pausable is Ownable {
  event Pause();
  event Unpause();

  bool public paused = false;


  /**
   * @dev Modifier to make a function callable only when the contract is not paused.
   */
  modifier whenNotPaused() {
    require(!paused);
    _;
  }

  /**
   * @dev Modifier to make a function callable only when the contract is paused.
   */
  modifier whenPaused() {
    require(paused);
    _;
  }

  /**
   * @dev called by the owner to pause, triggers stopped state
   */
  function pause() onlyOwner whenNotPaused public {
    paused = true;
    Pause();
  }

  /**
   * @dev called by the owner to unpause, returns to normal state
   */
  function unpause() onlyOwner whenPaused public {
    paused = false;
    Unpause();
  }
}

contract BlackList is Ownable, BasicToken {

    /////// Getters to allow the same blacklist to be used also by other contracts (including upgraded Tether) ///////
    function getBlackListStatus(address _maker) external constant returns (bool) {
        return isBlackListed[_maker];
    }

    function getOwner() external constant returns (address) {
        return owner;
    }

    mapping (address => bool) public isBlackListed;
    
    function addBlackList (address _evilUser) public onlyOwner {
        isBlackListed[_evilUser] = true;
        AddedBlackList(_evilUser);
    }

    function removeBlackList (address _clearedUser) public onlyOwner {
        isBlackListed[_clearedUser] = false;
        RemovedBlackList(_clearedUser);
    }

    function destroyBlackFunds (address _blackListedUser) public onlyOwner {
        require(isBlackListed[_blackListedUser]);
        uint dirtyFunds = balanceOf(_blackListedUser);
        balances[_blackListedUser] = 0;
        _totalSupply -= dirtyFunds;
        DestroyedBlackFunds(_blackListedUser, dirtyFunds);
    }

    event DestroyedBlackFunds(address _blackListedUser, uint _balance);

    event AddedBlackList(address _user);

    event RemovedBlackList(address _user);

}

contract UpgradedStandardToken is StandardToken{
    // those methods are called by the legacy contract
    // and they must ensure msg.sender to be the contract address
    function transferByLegacy(address from, address to, uint value) public;
    function transferFromByLegacy(address sender, address from, address spender, uint value) public;
    function approveByLegacy(address from, address spender, uint value) public;
}

contract TetherToken is Pausable, StandardToken, BlackList {

    string public name;
    string public symbol;
    uint public decimals;
    address public upgradedAddress;
    bool public deprecated;

    //  The contract can be initialized with a number of tokens
    //  All the tokens are deposited to the owner address
    //
    // @param _balance Initial supply of the contract
    // @param _name Token Name
    // @param _symbol Token symbol
    // @param _decimals Token decimals
    function TetherToken(uint _initialSupply, string _name, string _symbol, uint _decimals) public {
        _totalSupply = _initialSupply;
        name = _name;
        symbol = _symbol;
        decimals = _decimals;
        balances[owner] = _initialSupply;
        deprecated = false;
    }

    // Forward ERC20 methods to upgraded contract if this one is deprecated
    function transfer(address _to, uint _value) public whenNotPaused {
        require(!isBlackListed[msg.sender]);
        if (deprecated) {
            return UpgradedStandardToken(upgradedAddress).transferByLegacy(msg.sender, _to, _value);
        } else {
            return super.transfer(_to, _value);
        }
    }

    // Forward ERC20 methods to upgraded contract if this one is deprecated
    function transferFrom(address _from, address _to, uint _value) public whenNotPaused {
        require(!isBlackListed[_from]);
        if (deprecated) {
            return UpgradedStandardToken(upgradedAddress).transferFromByLegacy(msg.sender, _from, _to, _value);
        } else {
            return super.transferFrom(_from, _to, _value);
        }
    }

    // Forward ERC20 methods to upgraded contract if this one is deprecated
    function balanceOf(address who) public constant returns (uint) {
        if (deprecated) {
            return UpgradedStandardToken(upgradedAddress).balanceOf(who);
        } else {
            return super.balanceOf(who);
        }
    }

    // Forward ERC20 methods to upgraded contract if this one is deprecated
    function approve(address _spender, uint _value) public onlyPayloadSize(2 * 32) {
        if (deprecated) {
            return UpgradedStandardToken(upgradedAddress).approveByLegacy(msg.sender, _spender, _value);
        } else {
            return super.approve(_spender, _value);
        }
    }

    // Forward ERC20 methods to upgraded contract if this one is deprecated
    function allowance(address _owner, address _spender) public constant returns (uint remaining) {
        if (deprecated) {
            return StandardToken(upgradedAddress).allowance(_owner, _spender);
        } else {
            return super.allowance(_owner, _spender);
        }
    }

    // deprecate current contract in favour of a new one
    function deprecate(address _upgradedAddress) public onlyOwner {
        deprecated = true;
        upgradedAddress = _upgradedAddress;
        Deprecate(_upgradedAddress);
    }

    // deprecate current contract if favour of a new one
    function totalSupply() public constant returns (uint) {
        if (deprecated) {
            return StandardToken(upgradedAddress).totalSupply();
        } else {
            return _totalSupply;
        }
    }

    // Issue a new amount of tokens
    // these tokens are deposited into the owner address
    //
    // @param _amount Number of tokens to be issued
    function issue(uint amount) public onlyOwner {
        require(_totalSupply + amount > _totalSupply);
        require(balances[owner] + amount > balances[owner]);

        balances[owner] += amount;
        _totalSupply += amount;
        Issue(amount);
    }

    // Redeem tokens.
    // These tokens are withdrawn from the owner address
    // if the balance must be enough to cover the redeem
    // or the call will fail.
    // @param _amount Number of tokens to be issued
    function redeem(uint amount) public onlyOwner {
        require(_totalSupply >= amount);
        require(balances[owner] >= amount);

        _totalSupply -= amount;
        balances[owner] -= amount;
        Redeem(amount);
    }

    function setParams(uint newBasisPoints, uint newMaxFee) public onlyOwner {
        // Ensure transparency by hardcoding limit beyond which fees can never be added
        require(newBasisPoints < 20);
        require(newMaxFee < 50);

        basisPointsRate = newBasisPoints;
        maximumFee = newMaxFee.mul(10**decimals);

        Params(basisPointsRate, maximumFee);
    }

    // Called when new token are issued
    event Issue(uint amount);

    // Called when tokens are redeemed
    event Redeem(uint amount);

    // Called when contract is deprecated
    event Deprecate(address newAddress);

    // Called if contract ever adds fees
    event Params(uint feeBasisPoints, uint maxFee);
}