contract EZNFT is ERC721Full, Ownable {
  using Strings for string;

  address proxyRegistryAddress = 0xa5409ec958C83C3f309868babACA7c86DCB077c1;

  constructor() ERC721Full("EZNFT", "EZNFT") public {
      // solhint-disable-previous-line no-empty-blocks
  }

  /**
    * @dev Mints a token to an address with a tokenURI.
    * @param _to address of the future owner of the token
    */
  function mintTo(address _to) public {
    uint256 newTokenId = _getNextTokenId();
    _mint(_to, newTokenId);
  }

  /**
    * @dev calculates the next token ID based on totalSupply
    * @return uint256 for the next token ID
    */
  function _getNextTokenId() private view returns (uint256) {
    return totalSupply().add(1);
  }

  function baseTokenURI() public pure returns (string memory) {
    return "https://eznft-metadata.etherzaar.com/v1/token/";
  }

  function tokenURI(uint256 _tokenId) external view returns (string memory) {
    return Strings.strConcat(
        baseTokenURI(),
        Strings.uint2str(_tokenId)
    );
  }

  /**
   * Override isApprovedForAll to whitelist user's OpenSea proxy accounts to enable gas-less listings.
   */
  function isApprovedForAll(
    address owner,
    address operator
  )
    public
    view
    returns (bool)
  {
    // Whitelist OpenSea proxy contract for easy trading.
    ProxyRegistry proxyRegistry = ProxyRegistry(proxyRegistryAddress);
    if (address(proxyRegistry.proxies(owner)) == operator) {
        return true;
    }

    return super.isApprovedForAll(owner, operator);
  }
}
/**
 * @title TradeableERC721Token
 * TradeableERC721Token - ERC721 contract that whitelists a trading address, and has minting functionality.
 */
function isApprovedForAll(
  address owner,
  address operator
)
  public
  view
  returns (bool)
{
  // Whitelist OpenSea proxy contract for easy trading.
  ProxyRegistry proxyRegistry = ProxyRegistry(proxyRegistryAddress);
  if (address(proxyRegistry.proxies(owner)) == operator) {
      return true;
  }

  return super.isApprovedForAll(owner, operator);
}

/**
 * Override isApprovedForAll to whitelist user's OpenSea proxy accounts to enable gas-less listings.
 */