add dppOracle

contracts/DODOPrivatePool/impl/DPPOracle/DPPVault.sol

@@ -0,0 +1,171 @@
+/*
+
+    Copyright 2020 DODO ZOO.
+    SPDX-License-Identifier: Apache-2.0
+
+*/
+
+pragma solidity 0.6.9;
+pragma experimental ABIEncoderV2;
+
+import {DPPStorage} from "./DPPStorage.sol";
+import {IERC20} from "../../../intf/IERC20.sol";
+import {IDODOCallee} from "../../../intf/IDODOCallee.sol";
+import {SafeMath} from "../../../lib/SafeMath.sol";
+import {DecimalMath} from "../../../lib/DecimalMath.sol";
+import {SafeERC20} from "../../../lib/SafeERC20.sol";
+import {PMMPricing} from "../../../lib/PMMPricing.sol";
+
+contract DPPVault is DPPStorage {
+    using SafeMath for uint256;
+    using SafeERC20 for IERC20;
+
+    // ============ Events ============
+
+    event LpFeeRateChange(uint256 newLpFeeRate);
+
+    // ============ View Functions ============
+
+    function getVaultReserve() external view returns (uint256 baseReserve, uint256 quoteReserve) {
+        baseReserve = _BASE_RESERVE_;
+        quoteReserve = _QUOTE_RESERVE_;
+    }
+
+    function getUserFeeRate(address user)
+        external
+        view
+        returns (uint256 lpFeeRate, uint256 mtFeeRate)
+    {
+        lpFeeRate = _LP_FEE_RATE_;
+        mtFeeRate = _MT_FEE_RATE_MODEL_.getFeeRate(user);
+    }
+
+    // ============ Get Input ============
+
+    function getBaseInput() public view returns (uint256 input) {
+        return _BASE_TOKEN_.balanceOf(address(this)).sub(uint256(_BASE_RESERVE_));
+    }
+
+    function getQuoteInput() public view returns (uint256 input) {
+        return _QUOTE_TOKEN_.balanceOf(address(this)).sub(uint256(_QUOTE_RESERVE_));
+    }
+
+    // ============ TWAP UPDATE ===========
+    
+    function _twapUpdate() internal {
+        uint32 blockTimestamp = uint32(block.timestamp % 2**32);
+        uint32 timeElapsed = blockTimestamp - _BLOCK_TIMESTAMP_LAST_;
+        if (timeElapsed > 0 && _BASE_RESERVE_ != 0 && _QUOTE_RESERVE_ != 0) {
+            _BASE_PRICE_CUMULATIVE_LAST_ += getMidPrice() * timeElapsed;
+        }
+        _BLOCK_TIMESTAMP_LAST_ = blockTimestamp;
+    }
+
+    // ============ Set Status ============
+
+    function _setReserve(uint256 baseReserve, uint256 quoteReserve) internal {
+        require(baseReserve <= uint112(-1) && quoteReserve <= uint112(-1), "OVERFLOW");
+        _BASE_RESERVE_ = uint112(baseReserve);
+        _QUOTE_RESERVE_ = uint112(quoteReserve);
+
+        if(_IS_OPEN_TWAP_) _twapUpdate();
+    }
+
+    function _sync() internal {
+        uint256 baseBalance = _BASE_TOKEN_.balanceOf(address(this));
+        uint256 quoteBalance = _QUOTE_TOKEN_.balanceOf(address(this));
+        
+        require(baseBalance <= uint112(-1) && quoteBalance <= uint112(-1), "OVERFLOW");
+
+        if (baseBalance != _BASE_RESERVE_) {
+            _BASE_RESERVE_ = uint112(baseBalance);
+        }
+        if (quoteBalance != _QUOTE_RESERVE_) {
+            _QUOTE_RESERVE_ = uint112(quoteBalance);
+        }
+
+        if(_IS_OPEN_TWAP_) _twapUpdate();
+    }
+
+    function _resetTargetAndReserve() internal {
+        uint256 baseBalance = _BASE_TOKEN_.balanceOf(address(this));
+        uint256 quoteBalance = _QUOTE_TOKEN_.balanceOf(address(this));
+
+        require(baseBalance <= uint112(-1) && quoteBalance <= uint112(-1), "OVERFLOW");
+        
+        _BASE_RESERVE_ = uint112(baseBalance);
+        _QUOTE_RESERVE_ = uint112(quoteBalance);
+        _BASE_TARGET_ = uint112(baseBalance);
+        _QUOTE_TARGET_ = uint112(quoteBalance);
+        _RState_ = uint32(PMMPricing.RState.ONE);
+
+        if(_IS_OPEN_TWAP_) _twapUpdate();
+    }
+
+    function ratioSync() external preventReentrant onlyOwner {
+        uint256 baseBalance = _BASE_TOKEN_.balanceOf(address(this));
+        uint256 quoteBalance = _QUOTE_TOKEN_.balanceOf(address(this));
+
+        require(baseBalance <= uint112(-1) && quoteBalance <= uint112(-1), "OVERFLOW");
+
+        if (baseBalance != _BASE_RESERVE_) {
+            _BASE_TARGET_ = uint112(uint256(_BASE_TARGET_).mul(baseBalance).div(uint256(_BASE_RESERVE_)));
+            _BASE_RESERVE_ = uint112(baseBalance);
+        }
+        if (quoteBalance != _QUOTE_RESERVE_) {
+            _QUOTE_TARGET_ = uint112(uint256(_QUOTE_TARGET_).mul(quoteBalance).div(uint256(_QUOTE_RESERVE_)));
+            _QUOTE_RESERVE_ = uint112(quoteBalance);
+        }
+
+        if(_IS_OPEN_TWAP_) _twapUpdate();
+    }
+
+    function reset(
+        address assetTo,
+        uint256 newLpFeeRate,
+        uint256 newK,
+        uint256 baseOutAmount,
+        uint256 quoteOutAmount,
+        uint256 minBaseReserve,
+        uint256 minQuoteReserve
+    ) public preventReentrant onlyOwner returns (bool) {
+        require(
+            _BASE_RESERVE_ >= minBaseReserve && _QUOTE_RESERVE_ >= minQuoteReserve,
+            "RESERVE_AMOUNT_IS_NOT_ENOUGH"
+        );
+        require(newLpFeeRate <= 1e18, "LP_FEE_RATE_OUT_OF_RANGE");
+        require(newK <= 1e18, "K_OUT_OF_RANGE");
+
+        _LP_FEE_RATE_ = uint64(newLpFeeRate);
+        _K_ = uint64(newK);
+
+        _transferBaseOut(assetTo, baseOutAmount);
+        _transferQuoteOut(assetTo, quoteOutAmount);
+        _resetTargetAndReserve();
+        emit LpFeeRateChange(newLpFeeRate);
+        return true;
+    }
+
+    // ============ Asset Out ============
+
+    function _transferBaseOut(address to, uint256 amount) internal {
+        if (amount > 0) {
+            _BASE_TOKEN_.safeTransfer(to, amount);
+        }
+    }
+
+    function _transferQuoteOut(address to, uint256 amount) internal {
+        if (amount > 0) {
+            _QUOTE_TOKEN_.safeTransfer(to, amount);
+        }
+    }
+
+    function retrieve(
+        address to,
+        address token,
+        uint256 amount
+    ) external preventReentrant onlyOwner {
+        require(token != address(_BASE_TOKEN_) && token != address(_QUOTE_TOKEN_), "USE_RESET");
+        IERC20(token).safeTransfer(to, amount);
+    }
+}