// SPDX-License-Identifier: MIT

pragma solidity >=0.6;

pragma experimental ABIEncoderV2;

interface cERC20 {
	function mint(uint256 mintAmount) external returns (uint256);

	function redeemUnderlying(uint256 mintAmount) external returns (uint256);

	function exchangeRateCurrent() external returns (uint256);

	function exchangeRateStored() external view returns (uint256);

	function balanceOf(address addr) external view returns (uint256);

	function transfer(address to, uint256 amount) external returns (bool);

	function approve(address spender, uint256 amount) external returns (bool);
}

interface GoodDollar is cERC20 {
	function getFees(uint256 value) external view returns (uint256, bool);

	function mint(address to, uint256 mintAmount) external returns (uint256);

	function isMinter(address account) external view returns (bool);
}

interface Staking {
	struct Staker {
		// The staked DAI amount
		uint256 stakedDAI;
		// The latest block number which the
		// staker has staked tokens
		uint256 lastStake;
	}

	function stakeDAI(uint256 amount) external;

	function withdrawStake() external;

	function stakers(address staker) external view returns (Staker memory);
}

interface Uniswap {
	function swapExactETHForTokens(
		uint256 amountOutMin,
		address[] calldata path,
		address to,
		uint256 deadline
	) external payable returns (uint256[] memory amounts);

	function swapExactTokensForETH(
		uint256 amountIn,
		uint256 amountOutMin,
		address[] calldata path,
		address to,
		uint256 deadline
	) external returns (uint256[] memory amounts);

	function swapExactTokensForTokens(
		uint256 amountIn,
		uint256 amountOutMin,
		address[] calldata path,
		address to,
		uint256 deadline
	) external returns (uint256[] memory amounts);

	function WETH() external pure returns (address);

	function factory() external pure returns (address);

	function quote(
		uint256 amountA,
		uint256 reserveA,
		uint256 reserveB
	) external pure returns (uint256 amountB);

	function getAmountIn(
		uint256 amountOut,
		uint256 reserveIn,
		uint256 reserveOut
	) external pure returns (uint256 amountIn);

	function getAmountOut(
		uint256 amountI,
		uint256 reserveIn,
		uint256 reserveOut
	) external pure returns (uint256 amountOut);
}

interface UniswapFactory {
	function getPair(address tokenA, address tokenB)
		external
		view
		returns (address);
}

interface UniswapPair {
	function getReserves()
		external
		view
		returns (
			uint112 reserve0,
			uint112 reserve1,
			uint32 blockTimestampLast
		);

	function kLast() external view returns (uint256);
}

interface Reserve {
	function buy(
		address _buyWith,
		uint256 _tokenAmount,
		uint256 _minReturn
	) external returns (uint256);
}

interface IIdentity {
	function isWhitelisted(address user) external view returns (bool);

	function addWhitelistedWithDID(address account, string memory did) external;

	function removeWhitelisted(address account) external;

	function addIdentityAdmin(address account) external returns (bool);

	function setAvatar(address _avatar) external;
}

interface UBIScheme {
	function currentDay() external view returns (uint256);
}

interface ProxyAdmin {
	function getProxyImplementation(address proxy)
		external
		view
		returns (address);

	function getProxyAdmin(address proxy) external view returns (address);

	function upgrade(address proxy, address implementation) external;

	function owner() external view returns (address);

	function transferOwnership(address newOwner) external;
}