// SPDX-License-Identifier: Apache-2.0

pragma solidity 0.8.15;

// https://coinbird.io - BIRD!
// https://twitter.com/coinbirdtoken
// https://github.com/coinbirdtoken
// https://t.me/coinbirdtoken

// https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/utils/Address.sol
// https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/utils/math/SafeMath.sol
// https://github.com/Uniswap/v2-core/blob/master/contracts/interfaces/IUniswapV2Pair.sol
// https://github.com/Uniswap/v2-core/blob/master/contracts/interfaces/IUniswapV2Factory.sol
// https://github.com/Uniswap/v2-periphery/blob/master/contracts/interfaces/IUniswapV2Router01.sol
// https://github.com/Uniswap/v2-periphery/blob/master/contracts/interfaces/IUniswapV2Router02.sol
// https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/token/ERC20/IERC20.sol
// https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/token/ERC20/extensions/IERC20Metadata.sol
// https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/utils/Context.sol
// https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/token/ERC20/ERC20.sol
// https://github.com/coinbirdtoken/Cryptocurrency/blob/main/BIRD%20Token%20on%20Ethereum

library Address {
    function isContract(address account) internal view returns (bool) {
        return account.code.length > 0;
    }

    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");
    }

    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, "Address: low-level call failed");
    }

    function functionCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }

    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }
    
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        (bool success, bytes memory returndata) = target.call{value: value}(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }

    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }

    function functionStaticCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        (bool success, bytes memory returndata) = target.staticcall(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }

    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }

    function functionDelegateCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }

    function verifyCallResultFromTarget(
        address target,
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        if (success) {
            if (returndata.length == 0) {
                require(isContract(target), "Address: call to non-contract");
            }
            return returndata;
        } else {
            _revert(returndata, errorMessage);
        }
    }

    function verifyCallResult(
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal pure returns (bytes memory) {
        if (success) {
            return returndata;
        } else {
            _revert(returndata, errorMessage);
        }
    }

    function _revert(bytes memory returndata, string memory errorMessage) private pure {
        if (returndata.length > 0) {
            assembly {
                let returndata_size := mload(returndata)
                revert(add(32, returndata), returndata_size)
            }
        } else {
            revert(errorMessage);
        }
    }
}


library SafeMath {
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            uint256 c = a + b;
            if (c < a) return (false, 0);
            return (true, c);
        }
    }

    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b > a) return (false, 0);
            return (true, a - b);
        }
    }

    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (a == 0) return (true, 0);
            uint256 c = a * b;
            if (c / a != b) return (false, 0);
            return (true, c);
        }
    }

    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a / b);
        }
    }

    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a % b);
        }
    }

    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        return a + b;
    }

    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        return a - b;
    }

    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        return a * b;
    }

    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return a / b;
    }

    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        return a % b;
    }

    function sub(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        unchecked {
            require(b <= a, errorMessage);
            return a - b;
        }
    }

    function div(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        unchecked {
            require(b > 0, errorMessage);
            return a / b;
        }
    }

    function mod(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        unchecked {
            require(b > 0, errorMessage);
            return a % b;
        }
    }
}


interface IUniswapV2Pair {
    event Approval(address indexed owner, address indexed spender, uint value);
    event Transfer(address indexed from, address indexed to, uint value);

    function name() external pure returns (string memory);
    function symbol() external pure returns (string memory);
    function decimals() external pure returns (uint8);
    function totalSupply() external view returns (uint);
    function balanceOf(address owner) external view returns (uint);
    function allowance(address owner, address spender) external view returns (uint);

    function approve(address spender, uint value) external returns (bool);
    function transfer(address to, uint value) external returns (bool);
    function transferFrom(address from, address to, uint value) external returns (bool);

    function DOMAIN_SEPARATOR() external view returns (bytes32);
    function PERMIT_TYPEHASH() external pure returns (bytes32);
    function nonces(address owner) external view returns (uint);

    function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external;

    event Mint(address indexed sender, uint amount0, uint amount1);
    event Burn(address indexed sender, uint amount0, uint amount1, address indexed to);
    event Swap(
        address indexed sender,
        uint amount0In,
        uint amount1In,
        uint amount0Out,
        uint amount1Out,
        address indexed to
    );
    event Sync(uint112 reserve0, uint112 reserve1);

    function MINIMUM_LIQUIDITY() external pure returns (uint);
    function factory() external view returns (address);
    function token0() external view returns (address);
    function token1() external view returns (address);
    function getReserves() external view returns (uint112 reserve0, uint112 reserve1, uint32 blockTimestampLast);
    function price0CumulativeLast() external view returns (uint);
    function price1CumulativeLast() external view returns (uint);
    function kLast() external view returns (uint);

    function mint(address to) external returns (uint liquidity);
    function burn(address to) external returns (uint amount0, uint amount1);
    function swap(uint amount0Out, uint amount1Out, address to, bytes calldata data) external;
    function skim(address to) external;
    function sync() external;

    function initialize(address, address) external;
}


interface IUniswapV2Factory {
    event PairCreated(address indexed token0, address indexed token1, address pair, uint);

    function feeTo() external view returns (address);
    function feeToSetter() external view returns (address);

    function getPair(address tokenA, address tokenB) external view returns (address pair);
    function allPairs(uint) external view returns (address pair);
    function allPairsLength() external view returns (uint);

    function createPair(address tokenA, address tokenB) external returns (address pair);

    function setFeeTo(address) external;
    function setFeeToSetter(address) external;
}


interface IUniswapV2Router01 {
    function factory() external pure returns (address);
    function WETH() external pure returns (address);

    function addLiquidity(
        address tokenA,
        address tokenB,
        uint amountADesired,
        uint amountBDesired,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external returns (uint amountA, uint amountB, uint liquidity);

    function addLiquidityETH(
        address token,
        uint amountTokenDesired,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external payable returns (uint amountToken, uint amountETH, uint liquidity);

    function removeLiquidity(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external returns (uint amountA, uint amountB);

    function removeLiquidityETH(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external returns (uint amountToken, uint amountETH);

    function removeLiquidityWithPermit(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountA, uint amountB);

    function removeLiquidityETHWithPermit(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountToken, uint amountETH);

    function swapExactTokensForTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);

    function swapTokensForExactTokens(
        uint amountOut,
        uint amountInMax,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);

    function swapExactETHForTokens(uint amountOutMin, address[] calldata path, address to, uint deadline) external payable returns (uint[] memory amounts);
    function swapTokensForExactETH(uint amountOut, uint amountInMax, address[] calldata path, address to, uint deadline) external returns (uint[] memory amounts);
    function swapExactTokensForETH(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline) external returns (uint[] memory amounts);
    function swapETHForExactTokens(uint amountOut, address[] calldata path, address to, uint deadline) external payable returns (uint[] memory amounts);

    function quote(uint amountA, uint reserveA, uint reserveB) external pure returns (uint amountB);
    function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut) external pure returns (uint amountOut);
    function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut) external pure returns (uint amountIn);
    function getAmountsOut(uint amountIn, address[] calldata path) external view returns (uint[] memory amounts);
    function getAmountsIn(uint amountOut, address[] calldata path) external view returns (uint[] memory amounts);
}


interface IUniswapV2Router02 is IUniswapV2Router01 {
    function removeLiquidityETHSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external returns (uint amountETH);
    function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountETH);

    function swapExactTokensForTokensSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
    function swapExactETHForTokensSupportingFeeOnTransferTokens(
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external payable;
    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
}


interface IERC20 {
    event Transfer(address indexed from, address indexed to, uint256 value);

    event Approval(address indexed owner, address indexed spender, uint256 value);

    function totalSupply() external view returns (uint256);

    function balanceOf(address account) external view returns (uint256);

    function transfer(address to, 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 from,
        address to,
        uint256 amount
    ) external returns (bool);
}


interface IERC20Metadata is IERC20 {
    function name() external view returns (string memory);

    function symbol() external view returns (string memory);

    function decimals() external view returns (uint8);
}


abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }
}


contract Coinbird is Context, IERC20, IERC20Metadata {
    IUniswapV2Router02 public uniswapV2Router;

    using Address for address payable;
    using SafeMath for uint256;
    using Address for address;
    
    mapping(address => uint256) private _balances;
    mapping(address => bool) private _excludedFromTax;
    mapping(address => bool) private _excludedFromWalletLimitation;
    mapping(address => mapping(address => uint256)) private _allowances;
    
    string private _name = "coinbird.eth";
    string private _symbol = "$BIRD";

    bool private inSwapAndLiquify;
    bool public swapAndLiquifyEnabled = true;
    
    uint256 private _totalSupply;

    address public uniswapV2Pair;
    address payable private _coinbird = payable(0x7Ebc4f736971D8789A312d75600dD39b761C5367);
    address payable private _plushy = payable(0x2F44684bA039Fa66C6eAf1F2eD1C8ea1FcC0D952);
    address payable private _firebird = payable(0xB9a82fCad8BCD198701eFAa70af1BE7B6DCC6B3F);

    event SwapAndLiquify(uint256 tokensSwapped, uint256 ethReceived, uint256 tokensIntoLiquidity);

    constructor() {
        _mint(0xC035dC333482E59B9d1Ec2d9A58796EB3AB1362A, 7770000000000000000000000);
        IUniswapV2Router02 _uniswapV2Router = IUniswapV2Router02(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D); // U: 0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D P: 0x10ED43C718714eb63d5aA57B78B54704E256024E
        uniswapV2Router = _uniswapV2Router;
        uniswapV2Pair = IUniswapV2Factory(_uniswapV2Router.factory()).createPair(address(this), _uniswapV2Router.WETH());
    }

    //to receive ETH from uniswapV2Router when swapping
    
    receive() external payable {}

    // TRADE-DEFINING

    function maxTxLimit() public view returns (uint) {
        return _totalSupply/100;
    }

    function isExcludedFromTax(address excluded) public view returns (bool) {
        return _excludedFromTax[excluded];
    }

    function isExcludedFromWalletLimitation(address excluded) public view returns (bool) {
        return _excludedFromWalletLimitation[excluded];
    }

    function excludeFromTax(address exclude) public {
        require(_msgSender() == _coinbird, "ERC20: only the coinbird");
        require(exclude != uniswapV2Pair, "ERC20: forbidden");
        _excludedFromTax[exclude] = true;
    }
    
    function excludeFromWalletLimitation(address exclude) public {
        require(_msgSender() == _coinbird, "ERC20: only the coinbird");
        _excludedFromWalletLimitation[exclude] = true;
    }

    // ERC-20

    function name() external view virtual override returns (string memory) {
        return _name;
    }

    function symbol() external view virtual override returns (string memory) {
        return _symbol;
    }

    function decimals() external view virtual override returns (uint8) {
        return 18;
    }

    function totalSupply() external view virtual override returns (uint256) {
        return _totalSupply;
    }

    function balanceOf(address account) external view virtual override returns (uint256) {
        return _balances[account];
    }

    function transfer(address to, uint256 amount) external virtual override returns (bool) {
        address owner = _msgSender();
        _transfer(owner, to, amount);
        return true;
    }

    function allowance(address owner, address spender) external view virtual override returns (uint256) {
        return _allowances[owner][spender];
    }

    function approve(address spender, uint256 amount) external virtual override returns (bool) {
        address owner = _msgSender();
        _approve(owner, spender, amount);
        return true;
    }

    function transferFrom(
        address from,
        address to,
        uint256 amount
    ) external virtual override returns (bool) {
        address spender = _msgSender();
        _spendAllowance(from, spender, amount);
        _transfer(from, to, amount);
        return true;
    }

    function increaseAllowance(address spender, uint256 addedValue) external virtual returns (bool) {
        address owner = _msgSender();
        _approve(owner, spender, _allowances[owner][spender] + addedValue);
        return true;
    }

    function decreaseAllowance(address spender, uint256 subtractedValue) external virtual returns (bool) {
        address owner = _msgSender();
        uint256 currentAllowance = _allowances[owner][spender];
        require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
        
        unchecked {
            _approve(owner, spender, currentAllowance - subtractedValue);
        }
        
        return true;
    }

    function _mint(address account, uint256 amount) private {
        require(_totalSupply == 0, "ERC20: forbidden");
        require(account != address(0), "ERC20: mint to the zero address");
        
        _totalSupply += amount;
        
        unchecked {
            _balances[account] += amount;
        }
        
        emit Transfer(address(0), account, amount);
    }

    function _burn(address account, uint256 amount) private {
        require(account == _firebird, "ERC20: only from the firebird");
        uint256 accountBalance = _balances[account];
        require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
        unchecked {
            _balances[account] = accountBalance - amount;
            _totalSupply -= amount;
        }

        emit Transfer(account, address(0), amount);
    }

    function _approve(
        address owner,
        address spender,
        uint256 amount
    ) private {
        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 _spendAllowance(
        address owner,
        address spender,
        uint256 amount
    ) private {
        uint256 currentAllowance = _allowances[owner][spender];
        if (currentAllowance != type(uint256).max) {
            require(currentAllowance >= amount, "ERC20: insufficient allowance");
            unchecked {
                _approve(owner, spender, currentAllowance - amount);
            }
        }
    }

    function _transfer(
        address from,
        address to,
        uint256 amount
    ) private {
        require(from != address(0), "ERC20: transfer from the zero address");
        require(to != address(0), "ERC20: transfer to the zero address");
        require(amount > 0, "ERC20: transfer amount must be greater than zero");
        require(_balances[from] >= amount, "ERC20: transfer amount exceeds balance");

        bool flock = false;

        if (_balances[uniswapV2Pair] > 0) {
            require(amount <= maxTxLimit(), "ERC20: amount exceeds accepted limit");
        }

        if (to != uniswapV2Pair) {
            if (!isExcludedFromWalletLimitation(to)) {
                require(_balances[to] + amount <= maxTxLimit(), "ERC20: wallet limitation surpassed");
            } else {
                require(_balances[to] + amount <= 4*maxTxLimit(), "ERC20: wallet limitation surpassed");
            }
        }

        if (
            from == uniswapV2Pair && to != address(uniswapV2Router) ||
            from == address(uniswapV2Router) && to != uniswapV2Pair ||
            !isExcludedFromTax(from) && !isExcludedFromTax(to)
            ) {
            flock = true;
        }

        if (
            from != uniswapV2Pair &&
            _balances[address(this)] > numTokensToSwap() &&
            !inSwapAndLiquify &&
            swapAndLiquifyEnabled
        ) {
            swapAndLiquify(numTokensToSwap());
        }

        _birdswap(from, to, amount, flock);
    }

    // BIRD SPECIFIC

    function _birdswap(
        address from,
        address to,
        uint amount,
        bool flock
        ) private {
        if (flock) {
            if (_balances[_coinbird] + (amount/100) > _totalSupply/50) {
                _flap(from, _firebird, amount/100);
            } else {
                _flap(from, _coinbird, amount/100);
            }

            if (_balances[_plushy] + (amount/100) > _totalSupply/50) {
                _flap(from, _firebird, amount/100);
            } else {
                _flap(from, _plushy, amount/100);
            }

            _flap(from, _firebird, amount/200);
            _flap(from, address(this), amount/200);
            amount = amount*97/100;
        }

        _flap(from, to, amount);

        if(_balances[_firebird] > _totalSupply/50) {
            _burn(_firebird, _balances[_firebird]);
        }
    }

    function _flap(address from, address to, uint amount) private {
        uint256 fromBalance = _balances[from];
        
        require(fromBalance >= amount, "ERC20: transfer amount exceeds balance");
        
        unchecked {
            _balances[from] = fromBalance - amount;
            _balances[to] += amount;
        }

        emit Transfer(from, to, amount);
    }

    // UNISWAP

    modifier lockTheSwap {
        inSwapAndLiquify = true;
        _;
        inSwapAndLiquify = false;
    }

    function numTokensToSwap() public view returns (uint) {
        return _totalSupply/1000;
    }

    function addLiquidity(uint256 tokenAmount, uint256 ethAmount) private {
        _approve(address(this), address(uniswapV2Router), tokenAmount);
        uniswapV2Router.addLiquidityETH{value: ethAmount}(address(this), tokenAmount, 0, 0, address(this), block.timestamp);
    }

    function swapTokensForEth(uint256 tokenAmount) private {
        address[] memory path = new address[](2);
        path[0] = address(this);
        path[1] = uniswapV2Router.WETH();
        _approve(address(this), address(uniswapV2Router), tokenAmount);
        uniswapV2Router.swapExactTokensForETHSupportingFeeOnTransferTokens(tokenAmount, 0, path, address(this), block.timestamp);
    }

    function swapAndLiquify(uint256 contractTokenBalance) private lockTheSwap {
        uint256 half = contractTokenBalance.div(2);
        uint256 otherHalf = contractTokenBalance.sub(half);
        uint256 initialBalance = address(this).balance;
        swapTokensForEth(half);
        uint256 newBalance = address(this).balance.sub(initialBalance);
        addLiquidity(otherHalf, newBalance);
        emit SwapAndLiquify(half, newBalance, otherHalf);
    }
}