SPECTRE.sol

//
// Speculative Resistance (SPECTRE) is the fourth token from Read This Contract (RTC)!
// If you don't know what RTC is, read on and join the Telegram:
// > https://veravoss.github.io/rtc/
// > https://t.me/ReadThisContract
//
// SPECTRE is intended as a deflationary token with reducing supply and appreciating value, and a fair launch.
// It has simple rules:
//
// 0. SPECTRE-ETH pool on Uniswap will be prepared with 5 ETH and 50,000 SPECTRE ("V Liquidity"):
//    Pool creation will be split into steps to resist speculative bots. Pool will start with little liquidity
//    and more will be added every 10 minutes. Price may be suppressed to maintain the ability to add liquidity.
//    Monitor the Telegram group to know when the SPECTRE-ETH pool is finalised.
//
//    Total supply is 56,000 SPECTRE. 5,000 is airdropped to RTC holders and Uniswap LP holders of RTC pairs (-SWSH, -LIQLO, -ETH).
//    1,000 is kept in reserve to create future pools paired with SPECTRE. Minting is locked, supply is final.
//
// 1. Whenever SPECTRE-ETH Uniswap pool Ethereum liquidity is above 12 ETH, the following process can occur:
//    - 10% of "V Liquidity" is removed from the pool through Uniswap,
//    - all un-pooled ETH is used to regularly buy SPECTRE back from the pool at 1 ETH chunks,
//    - all un-pooled & bought-back SPECTRE, minus a 1% dev fee, is sent to Burn Address,
//
//    The process is triggered randomly. Can happen multiple times per day, or not at all, as long as the liquidity
//    condition is met. Think of it as a random, upwards rebasing of the pool's liquidity.
//
// 2. SPECTRE supply reduces logarithmically and "V Liquidity" approaches zero, effectively locking it over time.
//
// 3. SPECTRE tokens will be used to unlock RTC ecosystem lootboxes with NFTs possessing special abilities within
//    the RTC ecosystem! SPECTRE-ETH and other pairs will arrive to SwapShip.finance in near future.
//
// Good luck!
//
// Veronika
//
// //////////////////////////////////////////////////////////////////////////////// //
//                                                                                  //
//                               ////   //////   /////                              //
//                              //        //     //                                 //
//                              //        //     /////                              //
//                                                                                  //
//                              Never break the chain.                              //
//                                                                                  //
// //////////////////////////////////////////////////////////////////////////////// //
pragma solidity ^0.6.0;
contract Context {
    constructor () internal { }
    function _msgSender() internal view virtual returns (address payable) {
        return msg.sender;
    }
    function _msgData() internal view virtual returns (bytes memory) {
        this;
        return msg.data;
    }
}
pragma solidity ^0.6.0;
library SafeMath {
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");
        return c;
    }
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        return sub(a, b, "SafeMath: subtraction overflow");
    }
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        uint256 c = a - b;
        return c;
    }
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        if (a == 0) {
            return 0;
        }
        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");
        return c;
    }
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return div(a, b, "SafeMath: division by zero");
    }
    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        uint256 c = a / b;
        return c;
    }
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        return mod(a, b, "SafeMath: modulo by zero");
    }
    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b != 0, errorMessage);
        return a % b;
    }
}
pragma solidity ^0.6.0;
contract Ownable is Context {
    address private _owner;
    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
    constructor () internal {
        address msgSender = _msgSender();
        _owner = msgSender;
        emit OwnershipTransferred(address(0), msgSender);
    }
    function owner() public view returns (address) {
        return _owner;
    }
    modifier onlyOwner() {
        require(_owner == _msgSender(), "Ownable: caller is not the owner");
        _;
    }
    function renounceOwnership() public virtual onlyOwner {
        emit OwnershipTransferred(_owner, address(0));
        _owner = address(0);
    }
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }
}
pragma solidity ^0.6.2;
library Address {
    function isContract(address account) internal view returns (bool) {
        bytes32 codehash;
        bytes32 accountHash = 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470;
        assembly { codehash := extcodehash(account) }
        return (codehash != accountHash && codehash != 0x0);
    }
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");
        (bool success, ) = recipient.call{ value: amount }("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }
}
pragma solidity ^0.6.0;
interface IERC20 {
    function totalSupply() external view returns (uint256);
    function balanceOf(address account) external view returns (uint256);
    function transfer(address recipient, uint256 amount) external returns (bool);
    function allowance(address owner, address spender) external view returns (uint256);
    function approve(address spender, uint256 amount) external returns (bool);
    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
    event Transfer(address indexed from, address indexed to, uint256 value);
    event Approval(address indexed owner, address indexed spender, uint256 value);
}
pragma solidity ^0.6.0;
contract ERC20 is Context, IERC20 {
    using SafeMath for uint256;
    using Address for address;
    mapping (address => uint256) private _balances;
    mapping (address => mapping (address => uint256)) private _allowances;
    uint256 private _totalSupply;
    string private _name;
    string private _symbol;
    uint8 private _decimals;
    constructor (string memory name, string memory symbol) public {
        _name = name;
        _symbol = symbol;
        _decimals = 18;
    }
    function name() public view returns (string memory) {
        return _name;
    }
    function symbol() public view returns (string memory) {
        return _symbol;
    }
    function decimals() public view returns (uint8) {
        return _decimals;
    }
    function totalSupply() public view override returns (uint256) {
        return _totalSupply;
    }
    function balanceOf(address account) public view override returns (uint256) {
        return _balances[account];
    }
    function transfer(address recipient, uint256 amount) public virtual override returns (bool) {
        _transfer(_msgSender(), recipient, amount);
        return true;
    }
    function allowance(address owner, address spender) public view virtual override returns (uint256) {
        return _allowances[owner][spender];
    }
    function approve(address spender, uint256 amount) public virtual override returns (bool) {
        _approve(_msgSender(), spender, amount);
        return true;
    }
    function transferFrom(address sender, address recipient, uint256 amount) public virtual override returns (bool) {
        _transfer(sender, recipient, amount);
        _approve(sender, _msgSender(), _allowances[sender][_msgSender()].sub(amount, "ERC20: transfer amount exceeds allowance"));
        return true;
    }
    function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].add(addedValue));
        return true;
    }
    function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].sub(subtractedValue, "ERC20: decreased allowance below zero"));
        return true;
    }
    function _transfer(address sender, address recipient, uint256 amount) internal virtual {
        require(sender != address(0), "ERC20: transfer from the zero address");
        require(recipient != address(0), "ERC20: transfer to the zero address");
        _beforeTokenTransfer(sender, recipient, amount);
        _balances[sender] = _balances[sender].sub(amount, "ERC20: transfer amount exceeds balance");
        _balances[recipient] = _balances[recipient].add(amount);
        emit Transfer(sender, recipient, amount);
    }
    function _mint(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: mint to the zero address");
        _beforeTokenTransfer(address(0), account, amount);
        _totalSupply = _totalSupply.add(amount);
        _balances[account] = _balances[account].add(amount);
        emit Transfer(address(0), account, amount);
    }
    function _burn(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: burn from the zero address");
        _beforeTokenTransfer(account, address(0), amount);
        _balances[account] = _balances[account].sub(amount, "ERC20: burn amount exceeds balance");
        _totalSupply = _totalSupply.sub(amount);
        emit Transfer(account, address(0), amount);
    }
    function _approve(address owner, address spender, uint256 amount) internal virtual {
        require(owner != address(0), "ERC20: approve from the zero address");
        require(spender != address(0), "ERC20: approve to the zero address");
        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }
    function _setupDecimals(uint8 decimals_) internal {
        _decimals = decimals_;
    }
    function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual { }
}
pragma solidity ^0.6.0;
abstract contract ERC20Capped is ERC20 {
    uint256 private _cap;
    constructor (uint256 cap) public {
        require(cap > 0, "ERC20Capped: cap is 0");
        _cap = cap;
    }
    function cap() public view returns (uint256) {
        return _cap;
    }
    function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual override {
        super._beforeTokenTransfer(from, to, amount);
        if (from == address(0)) {
            require(totalSupply().add(amount) <= _cap, "ERC20Capped: cap exceeded");
        }
    }
}
pragma solidity ^0.6.0;
abstract contract ERC20Burnable is Context, ERC20 {
    function burn(uint256 amount) public virtual {
        _burn(_msgSender(), amount);
    }
    function burnFrom(address account, uint256 amount) public virtual {
        uint256 decreasedAllowance = allowance(account, _msgSender()).sub(amount, "ERC20: burn amount exceeds allowance");
        _approve(account, _msgSender(), decreasedAllowance);
        _burn(account, amount);
    }
}
pragma solidity ^0.6.0;
interface IERC165 {
    function supportsInterface(bytes4 interfaceId) external view returns (bool);
}
pragma solidity ^0.6.2;
library ERC165Checker {
    bytes4 private constant _INTERFACE_ID_INVALID = 0xffffffff;
    bytes4 private constant _INTERFACE_ID_ERC165 = 0x01ffc9a7;
    function supportsERC165(address account) internal view returns (bool) {
        return _supportsERC165Interface(account, _INTERFACE_ID_ERC165) &&
            !_supportsERC165Interface(account, _INTERFACE_ID_INVALID);
    }
    function supportsInterface(address account, bytes4 interfaceId) internal view returns (bool) {
        return supportsERC165(account) &&
            _supportsERC165Interface(account, interfaceId);
    }

    function supportsAllInterfaces(address account, bytes4[] memory interfaceIds) internal view returns (bool) {
        if (!supportsERC165(account)) {
            return false;
        }
        for (uint256 i = 0; i < interfaceIds.length; i++) {
            if (!_supportsERC165Interface(account, interfaceIds[i])) {
                return false;
            }
        }
        return true;
    }

    function _supportsERC165Interface(address account, bytes4 interfaceId) private view returns (bool) {
        (bool success, bool result) = _callERC165SupportsInterface(account, interfaceId);
        return (success && result);
    }

    function _callERC165SupportsInterface(address account, bytes4 interfaceId)
        private
        view
        returns (bool, bool)
    {
        bytes memory encodedParams = abi.encodeWithSelector(_INTERFACE_ID_ERC165, interfaceId);
        (bool success, bytes memory result) = account.staticcall{ gas: 30000 }(encodedParams);
        if (result.length < 32) return (false, false);
        return (success, abi.decode(result, (bool)));
    }
}
pragma solidity ^0.6.0;
contract ERC165 is IERC165 {
    bytes4 private constant _INTERFACE_ID_ERC165 = 0x01ffc9a7;

    mapping(bytes4 => bool) private _supportedInterfaces;
    constructor () internal {
        _registerInterface(_INTERFACE_ID_ERC165);
    }

    function supportsInterface(bytes4 interfaceId) public view override returns (bool) {
        return _supportedInterfaces[interfaceId];
    }

    function _registerInterface(bytes4 interfaceId) internal virtual {
        require(interfaceId != 0xffffffff, "ERC165: invalid interface id");
        _supportedInterfaces[interfaceId] = true;
    }
}
pragma solidity ^0.6.0;
contract TokenRecover is Ownable {

    function recoverERC20(address tokenAddress, uint256 tokenAmount) public onlyOwner {
        IERC20(tokenAddress).transfer(owner(), tokenAmount);
    }
}
pragma solidity ^0.6.0;
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));
    }
}
pragma solidity ^0.6.0;
abstract contract AccessControl is Context {
    using EnumerableSet for EnumerableSet.AddressSet;
    using Address for address;
    struct RoleData {
        EnumerableSet.AddressSet members;
        bytes32 adminRole;
    }
    mapping (bytes32 => RoleData) private _roles;
    bytes32 public constant DEFAULT_ADMIN_ROLE = 0x00;

    event RoleGranted(bytes32 indexed role, address indexed account, address indexed sender);

    event RoleRevoked(bytes32 indexed role, address indexed account, address indexed sender);

    function hasRole(bytes32 role, address account) public view returns (bool) {
        return _roles[role].members.contains(account);
    }

    function getRoleMemberCount(bytes32 role) public view returns (uint256) {
        return _roles[role].members.length();
    }

    function getRoleMember(bytes32 role, uint256 index) public view returns (address) {
        return _roles[role].members.at(index);
    }

    function getRoleAdmin(bytes32 role) public view returns (bytes32) {
        return _roles[role].adminRole;
    }

    function grantRole(bytes32 role, address account) public virtual {
        require(hasRole(_roles[role].adminRole, _msgSender()), "AccessControl: sender must be an admin to grant");
        _grantRole(role, account);
    }

    function revokeRole(bytes32 role, address account) public virtual {
        require(hasRole(_roles[role].adminRole, _msgSender()), "AccessControl: sender must be an admin to revoke");
        _revokeRole(role, account);
    }

    function renounceRole(bytes32 role, address account) public virtual {
        require(account == _msgSender(), "AccessControl: can only renounce roles for self");
        _revokeRole(role, account);
    }

    function _setupRole(bytes32 role, address account) internal virtual {
        _grantRole(role, account);
    }

    function _setRoleAdmin(bytes32 role, bytes32 adminRole) internal virtual {
        _roles[role].adminRole = adminRole;
    }
    function _grantRole(bytes32 role, address account) private {
        if (_roles[role].members.add(account)) {
            emit RoleGranted(role, account, _msgSender());
        }
    }
    function _revokeRole(bytes32 role, address account) private {
        if (_roles[role].members.remove(account)) {
            emit RoleRevoked(role, account, _msgSender());
        }
    }
}
pragma solidity ^0.6.0;
contract Roles is AccessControl {
    bytes32 public constant MINTER_ROLE = keccak256("MINTER");
    bytes32 public constant OPERATOR_ROLE = keccak256("OPERATOR");
    constructor () public {
        _setupRole(DEFAULT_ADMIN_ROLE, _msgSender());
        _setupRole(MINTER_ROLE, _msgSender());
        _setupRole(OPERATOR_ROLE, _msgSender());
    }
    modifier onlyMinter() {
        require(hasRole(MINTER_ROLE, _msgSender()), "Roles: caller does not have the MINTER role");
        _;
    }
    modifier onlyOperator() {
        require(hasRole(OPERATOR_ROLE, _msgSender()), "Roles: caller does not have the OPERATOR role");
        _;
    }
}
pragma solidity ^0.6.0;
contract SPECTRE is ERC20Capped, ERC20Burnable, Roles, TokenRecover {
    bool private _mintingFinished = false;
    bool private _transferEnabled = false;

    event MintFinished();

    event TransferEnabled();

    modifier canMint() {
        require(!_mintingFinished, "SPECTRE: minting is finished");
        _;
    }

    modifier canTransfer(address from) {
        require(
            _transferEnabled || hasRole(OPERATOR_ROLE, from),
            "SPECTRE: transfer is not enabled or from does not have the OPERATOR role"
        );
        _;
    }

    constructor()
        public
        ERC20Capped(56000000000000000000000)
        ERC20("Speculative Resistance RTC", "SPECTRE")
    {
        uint256 initialSupply = 56000000000000000000000;
        bool transferEnabled = true;
        bool mintingFinished = true;
        
        if (initialSupply > 0) {
            _mint(owner(), initialSupply);
        }
        if (mintingFinished) {
            finishMinting();
        }
        if (transferEnabled) {
            enableTransfer();
        }
    }

    function mintingFinished() public view returns (bool) {
        return _mintingFinished;
    }

    function transferEnabled() public view returns (bool) {
        return _transferEnabled;
    }

    function mint(address to, uint256 value) public canMint onlyMinter {
        _mint(to, value);
    }

    function transfer(address to, uint256 value) public virtual override(ERC20) canTransfer(_msgSender()) returns (bool) {
        return super.transfer(to, value);
    }

    function transferFrom(address from, address to, uint256 value) public virtual override(ERC20) canTransfer(from) returns (bool) {
        return super.transferFrom(from, to, value);
    }

    function finishMinting() public canMint onlyOwner {
        _mintingFinished = true;
        emit MintFinished();
    }

    function enableTransfer() public onlyOwner {
        _transferEnabled = true;
        emit TransferEnabled();
    }

    function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual override(ERC20, ERC20Capped) {
        super._beforeTokenTransfer(from, to, amount);
    }
}