SolidityLabs/zombie-project/zombieownership.sol

43 lines
1.3 KiB
Solidity

pragma solidity ^0.4.19;
import "./zombieattack.sol";
import "./erc721.sol";
import "./safemath.sol";
/// TODO: Substitua isto com um descrição natspec
contract ZombieOwnership is ZombieAttack, ERC721 {
using SafeMath for uint256;
mapping (uint => address) zombieApprovals;
function balanceOf(address _owner) public view returns (uint256 _balance) {
return ownerZombieCount[_owner];
}
function ownerOf(uint256 _tokenId) public view returns (address _owner) {
return zombieToOwner[_tokenId];
}
function _transfer(address _from, address _to, uint256 _tokenId) private {
ownerZombieCount[_to] = ownerZombieCount[_to].add(1);
ownerZombieCount[msg.sender] = ownerZombieCount[msg.sender].sub(1);
zombieToOwner[_tokenId] = _to;
Transfer(_from, _to, _tokenId);
}
function transfer(address _to, uint256 _tokenId) public onlyOwnerOf(_tokenId) {
_transfer(msg.sender, _to, _tokenId);
}
function approve(address _to, uint256 _tokenId) public onlyOwnerOf(_tokenId) {
zombieApprovals[_tokenId] = _to;
Approval(msg.sender, _to, _tokenId);
}
function takeOwnership(uint256 _tokenId) public {
require(zombieApprovals[_tokenId] == msg.sender);
address owner = ownerOf(_tokenId);
_transfer(owner, msg.sender, _tokenId);
}
}