// File: contracts/lib/SafeMath.sol

/*

Copyright 2020 DODO ZOO.
SPDX-License-Identifier: Apache-2.0

*/

pragma solidity 0.6.9;
pragma experimental ABIEncoderV2;


/**
* @title SafeMath
* @author DODO Breeder
*
* @notice Math operations with safety checks that revert on error
*/
library SafeMath {
function mul(uint256 a, uint256 b) internal pure returns (uint256) {
if (a == 0) {
return 0;
}

uint256 c = a * b;
require(c / a == b, "MUL_ERROR");

return c;
}

function div(uint256 a, uint256 b) internal pure returns (uint256) {
require(b > 0, "DIVIDING_ERROR");
return a / b;
}

function divCeil(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 quotient = div(a, b);
uint256 remainder = a - quotient * b;
if (remainder > 0) {
return quotient 1;
} else {
return quotient;
}
}

function sub(uint256 a, uint256 b) internal pure returns (uint256) {
require(b <= a, "SUB_ERROR");
return a - b;
}

function add(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a b;
require(c >= a, "ADD_ERROR");
return c;
}

function sqrt(uint256 x) internal pure returns (uint256 y) {
uint256 z = x / 2 1;
y = x;
while (z < y) {
y = z;
z = (x / z z) / 2;
}
}
}

// File: contracts/lib/InitializableOwnable.sol

/**
* @title Ownable
* @author DODO Breeder
*
* @notice Ownership related functions
*/
contract InitializableOwnable {
address public _OWNER_;
address public _NEW_OWNER_;
bool internal _INITIALIZED_;

// ============ Events ============

event OwnershipTransferPrepared(address indexed previousOwner, address indexed newOwner);

event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

// ============ Modifiers ============

modifier notInitialized() {
require(!_INITIALIZED_, "DODO_INITIALIZED");
_;
}

modifier onlyOwner() {
require(msg.sender == _OWNER_, "NOT_OWNER");
_;
}

// ============ Functions ============

function initOwner(address newOwner) public notInitialized {
_INITIALIZED_ = true;
_OWNER_ = newOwner;
}

function transferOwnership(address newOwner) public onlyOwner {
emit OwnershipTransferPrepared(_OWNER_, newOwner);
_NEW_OWNER_ = newOwner;
}

function claimOwnership() public {
require(msg.sender == _NEW_OWNER_, "INVALID_CLAIM");
emit OwnershipTransferred(_OWNER_, _NEW_OWNER_);
_OWNER_ = _NEW_OWNER_;
_NEW_OWNER_ = address(0);
}
}

// File: contracts/external/ERC20/CustomERC20.sol


contract CustomERC20 is InitializableOwnable {
using SafeMath for uint256;

string public name;
uint8 public decimals;
string public symbol;
uint256 public totalSupply;

uint256 public tradeBurnRatio;
uint256 public tradeFeeRatio;
address public team;
bool public isMintable;

mapping(address => uint256) balances;
mapping(address => mapping(address => uint256)) internal allowed;

event Transfer(address indexed from, address indexed to, uint256 amount);
event Approval(address indexed owner, address indexed spender, uint256 amount);
event Mint(address indexed user, uint256 value);
event Burn(address indexed user, uint256 value);

event ChangeTeam(address oldTeam, address newTeam);


function init(
address _creator,
uint256 _initSupply,
string memory _name,
string memory _symbol,
uint8 _decimals,
uint256 _tradeBurnRatio,
uint256 _tradeFeeRatio,
address _team,
bool _isMintable
) public {
initOwner(_creator);
name = _name;
symbol = _symbol;
decimals = _decimals;
totalSupply = _initSupply;
balances[_creator] = _initSupply;
require(_tradeBurnRatio >= 0 && _tradeBurnRatio <= 5000, "TRADE_BURN_RATIO_INVALID");
require(_tradeFeeRatio >= 0 && _tradeFeeRatio <= 5000, "TRADE_FEE_RATIO_INVALID");
tradeBurnRatio = _tradeBurnRatio;
tradeFeeRatio = _tradeFeeRatio;
team = _team;
isMintable = _isMintable;
emit Transfer(address(0), _creator, _initSupply);
}

function transfer(address to, uint256 amount) public returns (bool) {
_transfer(msg.sender,to,amount);
return true;
}

function balanceOf(address owner) public view returns (uint256 balance) {
return balances[owner];
}

function transferFrom(
address from,
address to,
uint256 amount
) public returns (bool) {
require(amount <= allowed[from][msg.sender], "ALLOWANCE_NOT_ENOUGH");
_transfer(from,to,amount);
allowed[from][msg.sender] = allowed[from][msg.sender].sub(amount);
return true;
}

function approve(address spender, uint256 amount) public returns (bool) {
allowed[msg.sender][spender] = amount;
emit Approval(msg.sender, spender, amount);
return true;
}

function allowance(address owner, address spender) public view returns (uint256) {
return allowed[owner][spender];
}


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");
require(balances[sender] >= amount, "ERC20: transfer amount exceeds balance");

balances[sender] = balances[sender].sub(amount);

uint256 burnAmount;
uint256 feeAmount;
if(tradeBurnRatio > 0) {
burnAmount = amount.mul(tradeBurnRatio).div(10000);
balances[address(0)] = balances[address(0)].add(burnAmount);
}

if(tradeFeeRatio > 0) {
feeAmount = amount.mul(tradeFeeRatio).div(10000);
balances[team] = balances[team].add(feeAmount);
}

balances[recipient] = balances[recipient].add(amount.sub(burnAmount).sub(feeAmount));

emit Transfer(sender, recipient, amount);
}

function burn(uint256 value) external {
require(isMintable, "NOT_MINTABEL_TOKEN");
require(balances[msg.sender] >= value, "VALUE_NOT_ENOUGH");

balances[msg.sender] = balances[msg.sender].sub(value);
totalSupply = totalSupply.sub(value);
emit Burn(msg.sender, value);
emit Transfer(msg.sender, address(0), value);
}

//=================== Ownable ======================
function mint(address user, uint256 value) external onlyOwner {
require(isMintable, "NOT_MINTABEL_TOKEN");
require(user == _OWNER_, "NOT_OWNER");

balances[user] = balances[user].add(value);
totalSupply = totalSupply.add(value);
emit Mint(user, value);
emit Transfer(address(0), user, value);
}

function changeTeamAccount(address newTeam) external onlyOwner {
require(tradeFeeRatio > 0, "NOT_TRADE_FEE_TOKEN");
emit ChangeTeam(team,newTeam);
team = newTeam;
}
}