add dppOracle

contracts/DODOPrivatePool/impl/DPPOracle/DPPOracle.sol

@@ -0,0 +1,84 @@
+/*
+
+    Copyright 2021 DODO ZOO.
+    SPDX-License-Identifier: Apache-2.0
+
+*/
+
+pragma solidity 0.6.9;
+pragma experimental ABIEncoderV2;
+
+import {IFeeRateModel} from "../../../lib/FeeRateModel.sol";
+import {IERC20} from "../../../intf/IERC20.sol";
+import {DPPTrader} from "./DPPTrader.sol";
+
+/**
+ * @title DODO PrivatePool
+ * @author DODO Breeder
+ *
+ * @notice DODOPrivatePool with oracle price
+ */
+contract DPPOracle is DPPTrader {
+
+    function init(
+        address owner,
+        address maintainer,
+        address baseTokenAddress,
+        address quoteTokenAddress,
+        uint256 lpFeeRate,
+        address mtFeeRateModel,
+        uint256 k,
+        address i,
+        bool isOpenTWAP
+    ) external {
+        initOwner(owner);
+
+        require(baseTokenAddress != quoteTokenAddress, "BASE_QUOTE_CAN_NOT_BE_SAME");
+        _BASE_TOKEN_ = IERC20(baseTokenAddress);
+        _QUOTE_TOKEN_ = IERC20(quoteTokenAddress);
+
+        _MAINTAINER_ = maintainer;
+        _MT_FEE_RATE_MODEL_ = IFeeRateModel(mtFeeRateModel);
+        
+        require(lpFeeRate <= 1e18, "LP_FEE_RATE_OUT_OF_RANGE");
+        require(k <= 1e18, "K_OUT_OF_RANGE");
+        require(i !=  address(0), "INVALID_ORACLE");
+
+        _LP_FEE_RATE_ = uint64(lpFeeRate);
+        _K_ = uint64(k);
+        _I_ = i;
+
+        _IS_OPEN_TWAP_ = isOpenTWAP;
+        if(isOpenTWAP) _BLOCK_TIMESTAMP_LAST_ = uint32(block.timestamp % 2**32);
+        
+        _resetTargetAndReserve();
+    }
+
+
+    function tuneParameters(
+        uint256 newLpFeeRate,
+        uint256 newK,
+        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);
+
+        emit LpFeeRateChange(newLpFeeRate);
+        return true;
+    }
+
+
+    // ============ Version Control ============
+
+    function version() external pure returns (string memory) {
+        return "DPP Oracle 1.0.0";
+    }
+}