From 0d60d29f80a0cf01d46a445f71f4be73dcbbaf2e Mon Sep 17 00:00:00 2001
From: Thrilok Kumar <thrilok2000@gmail.com>
Date: Tue, 4 May 2021 17:17:04 +0530
Subject: [PATCH] Added InstaMappings

---
 contracts/mapping/InstaMappings.sol | 58 +++++++++++++++++++++++++++++
 1 file changed, 58 insertions(+)
 create mode 100644 contracts/mapping/InstaMappings.sol

diff --git a/contracts/mapping/InstaMappings.sol b/contracts/mapping/InstaMappings.sol
new file mode 100644
index 00000000..145383ec
--- /dev/null
+++ b/contracts/mapping/InstaMappings.sol
@@ -0,0 +1,58 @@
+pragma solidity ^0.7.0;
+pragma experimental ABIEncoderV2;
+
+import { AccessControl } from "@openzeppelin/contracts/access/AccessControl.sol";
+interface IndexInterface {
+    function master() external view returns (address);
+}
+
+contract InstaMappings is AccessControl {
+    IndexInterface public constant instaIndex = IndexInterface(0x2971AdFa57b20E5a416aE5a708A8655A9c74f723);
+
+    bytes32 public constant ADMIN_ROLE = keccak256("ADMIN_ROLE");
+
+    function setMaster() public {
+        require(msg.sender == address(this), "msg.sender is not this contract");
+        uint256 adminCount = getRoleMemberCount(DEFAULT_ADMIN_ROLE);
+        require(adminCount == 1, "setMaster::Wrong-admin-count");
+        address currentMaster = getRoleMember(DEFAULT_ADMIN_ROLE, 0);
+        address master = instaIndex.master();
+        
+        if (currentMaster != master) {
+            grantRole(DEFAULT_ADMIN_ROLE, master);
+            revokeRole(DEFAULT_ADMIN_ROLE, currentMaster);
+        }
+
+        adminCount = getRoleMemberCount(DEFAULT_ADMIN_ROLE);
+        require(adminCount == 1, "setMaster::Wrong-admin-count");
+        require(hasRole(DEFAULT_ADMIN_ROLE, master), "setMaster::InstaIndex-master-not-set");
+    }
+
+    constructor() {
+        _setupRole(DEFAULT_ADMIN_ROLE, instaIndex.master());
+        _setRoleAdmin(DEFAULT_ADMIN_ROLE, ADMIN_ROLE);
+        _setupRole(ADMIN_ROLE, address(this));
+    }
+
+    function getMappingContractRole(address mappingContract) public pure returns (bytes32 role){
+        assembly {
+            role := mload(add(mappingContract, 32))
+        }
+    }
+
+    function hasRole(address mappingAddr, address account) public view returns (bool) {
+        return super.hasRole(getMappingContractRole(mappingAddr), account);
+    }
+
+    function grantRole(address mappingAddr, address account) public {
+        super.grantRole(getMappingContractRole(mappingAddr), account);
+    }
+
+    function revokeRole(address mappingAddr, address account) public {
+        super.revokeRole(getMappingContractRole(mappingAddr), account);
+    }
+
+    function renounceRole(address mappingAddr, address account) public {
+        super.renounceRole(getMappingContractRole(mappingAddr), account);
+    }
+}
\ No newline at end of file