/*

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

*/

pragma solidity 0.6.9;
pragma experimental ABIEncoderV2;

import {ReentrancyGuard} from "../../lib/ReentrancyGuard.sol";
import {SafeMath} from "../../lib/SafeMath.sol";
import {DODOMath} from "../../lib/DODOMath.sol";
import {DecimalMath} from "../../lib/DecimalMath.sol";
import {IFeeRateModel} from "../../lib/FeeRateModel.sol";
import {IERC20} from "../../intf/IERC20.sol";
import {PMMPricing} from "../../lib/PMMPricing.sol";

contract DVMStorage is ReentrancyGuard {
    using SafeMath for uint256;

    bool public _IS_OPEN_TWAP_ = false;

    bool internal _DVM_INITIALIZED_;

    // ============ Core Address ============

    address public _MAINTAINER_;

    IERC20 public _BASE_TOKEN_;
    IERC20 public _QUOTE_TOKEN_;

    uint112 public _BASE_RESERVE_;
    uint112 public _QUOTE_RESERVE_;
    uint32 public _BLOCK_TIMESTAMP_LAST_;

    uint256 public _BASE_PRICE_CUMULATIVE_LAST_;

    // ============ Shares (ERC20) ============

    string public symbol;
    uint8 public decimals;
    string public name;

    uint256 public totalSupply;
    mapping(address => uint256) internal _SHARES_;
    mapping(address => mapping(address => uint256)) internal _ALLOWED_;

    // ================= Permit ======================

    bytes32 public DOMAIN_SEPARATOR;
    // keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)");
    bytes32 public constant PERMIT_TYPEHASH = 0x6e71edae12b1b97f4d1f60370fef10105fa2faae0126114a169c64845d6126c9;
    mapping(address => uint256) public nonces;

    // ============ Variables for Pricing ============

    uint256 public _LP_FEE_RATE_;
    IFeeRateModel public _MT_FEE_RATE_MODEL_;
    uint256 public _K_;
    uint256 public _I_;


    // ============ Helper Functions ============

    function getPMMState() public view returns (PMMPricing.PMMState memory state) {
        state.i = _I_;
        state.K = _K_;
        state.B = _BASE_RESERVE_;
        state.Q = _QUOTE_RESERVE_;
        state.B0 = 0; // will be calculated in adjustedTarget
        state.Q0 = 0;
        state.R = PMMPricing.RState.ABOVE_ONE;
        PMMPricing.adjustedTarget(state);
    }

    function getPMMStateForCall() 
        external 
        view 
        returns (
            uint256 i,
            uint256 K,
            uint256 B,
            uint256 Q,
            uint256 B0,
            uint256 Q0,
            uint256 R
        )
    {
        PMMPricing.PMMState memory state = getPMMState();
        i = state.i;
        K = state.K;
        B = state.B;
        Q = state.Q;
        B0 = state.B0;
        Q0 = state.Q0;
        R = uint256(state.R);
    }

    function getMidPrice() public view returns (uint256 midPrice) {
        return PMMPricing.getMidPrice(getPMMState());
    }
}