/** *Submitted for verification at Etherscan.io on 2020-11-08 */ /** *Submitted for verification at Etherscan.io on 2020-11-07 */ pragma solidity 0.6.12; // SPDX-License-Identifier: No License library SafeMath { function mul(uint256 a, uint256 b) internal pure returns (uint256) { uint256 c = a * b; assert(a == 0 || c / a == b); return c; } function div(uint256 a, uint256 b) internal pure returns (uint256) { require(b >0 ) ; uint256 c = a / b; 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; } } library EnumerableSet { struct Set { bytes32[] _values; mapping (bytes32 => uint256) _indexes; } function _add(Set storage set, bytes32 value) private returns (bool) { if (!_contains(set, value)) { set._values.push(value); set._indexes[value] = set._values.length; return true; } else { return false; } } function _remove(Set storage set, bytes32 value) private returns (bool) { uint256 valueIndex = set._indexes[value]; if (valueIndex != 0) { uint256 toDeleteIndex = valueIndex - 1; uint256 lastIndex = set._values.length - 1; bytes32 lastvalue = set._values[lastIndex]; set._values[toDeleteIndex] = lastvalue; set._indexes[lastvalue] = toDeleteIndex + 1; set._values.pop(); delete set._indexes[value]; return true; } else { return false; } } function _contains(Set storage set, bytes32 value) private view returns (bool) { return set._indexes[value] != 0; } function _length(Set storage set) private view returns (uint256) { return set._values.length; } function _at(Set storage set, uint256 index) private view returns (bytes32) { require(set._values.length > index, "EnumerableSet: index out of bounds"); return set._values[index]; } struct AddressSet { Set _inner; } function add(AddressSet storage set, address value) internal returns (bool) { return _add(set._inner, bytes32(uint256(value))); } function remove(AddressSet storage set, address value) internal returns (bool) { return _remove(set._inner, bytes32(uint256(value))); } function contains(AddressSet storage set, address value) internal view returns (bool) { return _contains(set._inner, bytes32(uint256(value))); } function length(AddressSet storage set) internal view returns (uint256) { return _length(set._inner); } function at(AddressSet storage set, uint256 index) internal view returns (address) { return address(uint256(_at(set._inner, index))); } struct UintSet { Set _inner; } function add(UintSet storage set, uint256 value) internal returns (bool) { return _add(set._inner, bytes32(value)); } function remove(UintSet storage set, uint256 value) internal returns (bool) { return _remove(set._inner, bytes32(value)); } function contains(UintSet storage set, uint256 value) internal view returns (bool) { return _contains(set._inner, bytes32(value)); } function length(UintSet storage set) internal view returns (uint256) { return _length(set._inner); } function at(UintSet storage set, uint256 index) internal view returns (uint256) { return uint256(_at(set._inner, index)); } } contract Ownable { address public owner; event OwnershipTransferred(address indexed previousOwner, address indexed newOwner); /** * @dev The Ownable constructor sets the original `owner` of the contract to the sender * account. */ constructor() 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) onlyOwner public { require(newOwner != address(0)); emit OwnershipTransferred(owner, newOwner); owner = newOwner; } } interface Token { function transferFrom(address, address, uint256) external returns (bool); function transfer(address, uint256) external returns (bool); } contract PredictzDex is Ownable { using SafeMath for uint256; using EnumerableSet for EnumerableSet.AddressSet; /* swapOwners[i] = [ 0 => Swap ID, 1 => Swap Owner, 2 => Swap Token, 3 => Swap Quanitiy, 4 => Swap Deadline, 5 => Swap Status, 0 => Pending, 1 => Received, 2 => Finished ] */ struct Swap { address owner; address token; uint256 quantity; uint256 balance; uint256 decimals; uint256 rate; uint256 deadline; uint256 status; bool exists; } mapping(uint256 => Swap) swaps; uint256[] public swapOwners; function getAllSwaps() view public returns (uint256[] memory){ return swapOwners; } function swap(uint256 swapID , address token, uint256 quantity,uint256 rate , uint256 decimals , uint256 deadline) public returns (uint256) { require(quantity > 0, "Cannot Swap with 0 Tokens"); require(deadline > now, "Cannot Swap for before time"); require(Token(token).transferFrom(msg.sender, address(this), quantity), "Insufficient Token Allowance"); require(swaps[swapID].exists != true , "Swap already Exists" ); Swap storage newswap = swaps[swapID]; newswap.owner = msg.sender; newswap.token = token; newswap.quantity = quantity ; newswap.balance = quantity ; newswap.decimals = decimals ; newswap.rate = rate ; newswap.deadline = deadline; newswap.status = 0 ; newswap.exists = true ; swapOwners.push(swapID) ; } function getSwap(uint256 _swapID ) view public returns (address , address , uint256, uint256 , uint256 , uint256 , uint256 ) { return (swaps[_swapID].owner , swaps[_swapID].token , swaps[_swapID].rate , swaps[_swapID].deadline , swaps[_swapID].quantity , swaps[_swapID].status , swaps[_swapID].balance ); } function getSwapDecimals(uint256 _swapID ) view public returns (uint256 ) { return ( swaps[_swapID].decimals ); } function calculateFee(uint256 _swapID , uint256 tokenAmt ) view public returns ( uint256 , uint256 , uint256 ) { return (swaps[_swapID].balance , swaps[_swapID].deadline , swaps[_swapID].rate.mul(tokenAmt) ); } function calculateToken(uint256 _swapID , uint256 bidamt ) view public returns ( uint256 ) { return (bidamt.div(swaps[_swapID].rate)) ; } function calculateRate(uint256 equivalentToken) pure public returns ( uint256 ) { uint256 base = 1e18 ; return (base.div(equivalentToken)) ; } function buy(uint256 amount, uint256 _swapID , uint256 tokenAmt) payable public { require(swaps[_swapID].balance >= tokenAmt, "Not Enough Tokens"); require(swaps[_swapID].deadline > now, "Pool Expired"); require(msg.value == amount); require(msg.value == swaps[_swapID].rate.mul(tokenAmt)); Swap storage singleswap = swaps[_swapID]; singleswap.balance = singleswap.balance.sub(tokenAmt.mul(singleswap.decimals)) ; transferAnyERC20Tokens(singleswap.token, msg.sender , tokenAmt.mul(singleswap.decimals) ); } function withdraw() public onlyOwner{ msg.sender.transfer(address(this).balance); } function transferAnyERC20Tokens(address _tokenAddr, address _to, uint256 _amount) private { Token(_tokenAddr).transfer(_to, _amount); } function OwnertransferAnyERC20Tokens(address _tokenAddr, address _to, uint256 _amount) public onlyOwner { Token(_tokenAddr).transfer(_to, _amount); } }