restruct contract repo

contracts/lib/PermissionManager.sol

@@ -0,0 +1,53 @@
+/*
+
+    Copyright 2020 DODO ZOO.
+    SPDX-License-Identifier: Apache-2.0
+
+*/
+
+pragma solidity 0.6.9;
+pragma experimental ABIEncoderV2;
+
+import {InitializableOwnable} from "./InitializableOwnable.sol";
+
+contract PermissionManager is InitializableOwnable {
+
+  bool public _BLACKLIST_MODE_ON_;
+
+  mapping(address => bool) internal _whitelist_;
+  mapping(address => bool) internal _blacklist_;
+
+  function isAllowed(address account) external view returns(bool){
+    if (_BLACKLIST_MODE_ON_) {
+      return !_blacklist_[account];
+    } else {
+      return _whitelist_[account];
+    }
+  }
+
+  function openBlacklist() external onlyOwner {
+    _BLACKLIST_MODE_ON_ = true;
+  }
+
+  function openWhitelist() external onlyOwner {
+    _BLACKLIST_MODE_ON_ = true;
+
+  }
+
+  function addToWhitelist(address account) external onlyOwner{
+    _whitelist_[account] = true;
+  }
+
+  function removeFromWhitelist(address account) external onlyOwner{
+    _whitelist_[account] = false;
+  }
+
+  function addToBlacklist(address account) external onlyOwner{
+    _blacklist_[account] = true;
+  }
+
+  function removeFromBlacklist(address account) external onlyOwner{
+    _blacklist_[account] = false;
+  }
+
+}