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Warning: Visibility for constructor is ignored. If you want the contract to be non-deployable, making it "abstract" is sufficient. constructor() public { ^ (Relevant source part starts here and spans across multiple lines).
Warning: Visibility for constructor is ignored. If you want the contract to be non-deployable, making it "abstract" is sufficient. constructor() public { ^ (Relevant source part starts here and spans across multiple lines).
// SPDX-License-Identifier: UNLICENSED
pragma solidity ^0.7.6;
/**
* @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.
*/
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.
*/
function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
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.
*/
function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
require(b != 0, errorMessage);
return a % b;
}
function ceil(uint256 a, uint256 m) internal pure returns (uint256 r) {
return (a + m - 1) / m * m;
}
}
// ----------------------------------------------------------------------------
// ERC Token Standard #20 Interface
// https://github.com/ethereum/EIPs/blob/master/EIPS/eip-20-token-standard.md
// ----------------------------------------------------------------------------
/**
* @dev Interface of the ERC20 standard as defined in the EIP.
*/
interface IERC20 {
/**
* @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 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);
}
// ----------------------------------------------------------------------------
// Owned contract
// ----------------------------------------------------------------------------
contract Owned {
address payable public owner;
event OwnershipTransferred(address indexed _from, address indexed _to);
constructor() public {
owner = msg.sender;
}
modifier onlyOwner {
require(msg.sender == owner, "Only allowed by owner");
_;
}
function transferOwnership(address payable _newOwner) external onlyOwner {
require(_newOwner != address(0),"Invalid address passed");
owner = _newOwner;
emit OwnershipTransferred(msg.sender, _newOwner);
}
}
contract ZOE_Stake is Owned {
using SafeMath for uint256;
IERC20 public ZOE;
uint256 public totalClaimedRewards;
uint256 public totalStaked;
struct Account{
uint256 stakedAmount;
uint256 rewardsClaimed;
uint256 pending;
uint256 stakingOpt;
uint256 stakingEndDate;
uint256 rewardPercentage;
}
mapping(address => Account) public stakers;
struct StakingOpts{
uint256 stakingPeriod;
uint256 stakingPercentage;
}
StakingOpts[4] public stakingOptions;
event RewardClaimed(address claimer, uint256 reward);
event UnStaked(address claimer, uint256 stakedTokens);
event Staked(address staker, uint256 tokens, uint256 stakingOption);
constructor() public {
/*
1 week: 5% ROI
1 month: 25% ROI
3 months: 100% ROI
6 months: 245% ROI
*/
stakingOptions[0].stakingPeriod = 7 days;
stakingOptions[0].stakingPercentage = 5;
stakingOptions[1].stakingPeriod = 30 days; // 1 month
stakingOptions[1].stakingPercentage = 25;
stakingOptions[2].stakingPeriod = 90 days;
stakingOptions[2].stakingPercentage = 100;
stakingOptions[3].stakingPeriod = 180 days;
stakingOptions[3].stakingPercentage = 245;
owner = 0xa97F07bc8155f729bfF5B5312cf42b6bA7c4fCB9;
}
// ------------------------------------------------------------------------
// Set Token Address
// only Owner can use it
// @param _tokenAddress the address of token
// -----------------------------------------------------------------------
function setTokenAddress(address _tokenAddress) external onlyOwner{
ZOE = IERC20(_tokenAddress);
}
// ------------------------------------------------------------------------
// Start the staking or add to existing stake
// user must approve the staking contract to transfer tokens before staking
// @param _amount number of tokens to stake
// ------------------------------------------------------------------------
function STAKE(uint256 _amount, uint256 optionNumber) external {
require(optionNumber >= 1 && optionNumber <= 4, "Invalid option choice");
require(stakers[msg.sender].stakedAmount == 0, "Your stake is already running");
// no tax will be applied upon staking IFY
totalStaked = totalStaked.add(_amount);
// record it in contract's storage
stakers[msg.sender].stakedAmount = stakers[msg.sender].stakedAmount.add(_amount); // add to the stake or fresh stake
stakers[msg.sender].stakingOpt = optionNumber;
stakers[msg.sender].stakingEndDate = block.timestamp.add(stakingOptions[optionNumber.sub(1)].stakingPeriod);
stakers[msg.sender].rewardPercentage = stakingOptions[optionNumber.sub(1)].stakingPercentage;
emit Staked(msg.sender, _amount, optionNumber);
// transfer the tokens from caller to staking contract
require(ZOE.transferFrom(msg.sender, address(this), _amount));
}
function Exit() external{
if(pendingReward(msg.sender) > 0)
ClaimReward();
if(stakers[msg.sender].stakedAmount > 0)
UnStake();
}
// ------------------------------------------------------------------------
// Claim reward
// @required user must be a staker
// @required must be claimable
// ------------------------------------------------------------------------
function ClaimReward() public {
require(pendingReward(msg.sender) > 0, "nothing pending to claim");
require(block.timestamp > stakers[msg.sender].stakingEndDate, "claim date has not reached");
uint256 reward = pendingReward(msg.sender);
// add claimed reward to global stats
totalClaimedRewards = totalClaimedRewards.add(reward);
// add the reward to total claimed rewards
stakers[msg.sender].rewardsClaimed = stakers[msg.sender].rewardsClaimed.add(reward);
emit RewardClaimed(msg.sender, reward);
// transfer the reward tokens
require(ZOE.transfer(msg.sender, reward), "reward transfer failed");
}
// ------------------------------------------------------------------------
// Unstake the tokens
// @required user must be a staker
// @required must be claimable
// ------------------------------------------------------------------------
function UnStake() public {
uint256 stakedAmount = stakers[msg.sender].stakedAmount;
require(stakedAmount > 0, "insufficient stake");
require(block.timestamp > stakers[msg.sender].stakingEndDate, "staking period has not ended");
totalStaked = totalStaked.sub(stakedAmount);
if(pendingReward(msg.sender) > 0)
stakers[msg.sender].pending = pendingReward(msg.sender);
stakers[msg.sender].stakedAmount = 0;
emit UnStaked(msg.sender, stakedAmount);
// transfer staked tokens
require(ZOE.transfer(msg.sender, stakedAmount));
}
// ------------------------------------------------------------------------
// Query to get the pending reward
// ------------------------------------------------------------------------
function pendingReward(address user) public view returns(uint256 _pendingReward){
uint256 reward = (onePercent(stakers[user].stakedAmount)).mul(stakers[user].rewardPercentage);
reward = reward.sub(stakers[user].rewardsClaimed);
return reward.add(stakers[msg.sender].pending);
}
// ------------------------------------------------------------------------
// Private function to calculate 1% percentage
// ------------------------------------------------------------------------
function onePercent(uint256 _tokens) private pure returns (uint256){
uint256 roundValue = _tokens.ceil(100);
uint onePercentofTokens = roundValue.mul(100).div(100 * 10**uint(2));
return onePercentofTokens;
}
}
