Merge branch 'main' into feat_checkdetails

contract/Database.sol

@@ -1,4 +1,3 @@
-// SPDX-License-Identifier: MI
 // SPDX-License-Identifier: MIT
 pragma solidity >=0.7.0<0.9.0;
 
@@ -12,26 +11,73 @@ contract Database{
         string batchNo;
 
     }
-
+
+
+
+
+
     mapping( address => Details) private list;
 
     uint256 private count=0;
+
+
+
+
+    mapping (string => bool) public added;
+
+
+    address public admin;
+    bool alreadyset=false;
+
     constructor()
     {
 
     }
 
+
     modifier personPresent{
         require(keccak256(abi.encodePacked(list[msg.sender].aadharId)) != keccak256(abi.encodePacked("")), "Person doesn't exist");
         _;
     }
-    function addPerson(string memory aadharId,string memory name, string memory DOB, string memory phoneNo, string memory rollNo, string memory batchNo) public 
+
+
+
+    modifier Added (string memory aadhar) 
+    {
+        require(!added[aadhar],"Details already added");
+        _;
+    }
+    modifier onlyOnce()
+    {
+        require(!alreadyset,"Admin is already set");
+        _;
+    }
+    modifier onlyAdmin()
+    {
+        require(msg.sender==admin,"Only admin can call this function");
+        _;
+    }
+    function set_Admin( address _admin) public onlyOnce()
+    {
+        admin=_admin;
+        alreadyset=true;
+    }
+    function changeAdmin(address newadmin) public onlyAdmin()
+    {
+        admin=newadmin;
+
+    }
+
+    function addPerson(string memory aadharId,string memory name, string memory DOB, string memory phoneNo, string memory rollNo, string memory batchNo) public Added (aadharId)
     {
         Details memory person = Details({aadharId: aadharId,name: name,DOB: DOB,phoneNo: phoneNo, rollNo: rollNo, batchNo: batchNo});
         list[msg.sender]=person;
+        added[aadharId]=true;
+
         count++;
     }
 
+
     function updateDetails(string memory aadharId,string memory name, string memory DOB, string memory phoneNo, string memory rollNo, string memory batchNo)public personPresent{
         Details storage person = list[msg.sender];
         person.aadharId = aadharId;
@@ -40,6 +86,7 @@ contract Database{
         person.phoneNo = phoneNo;
         person.rollNo = rollNo;
         person.batchNo = batchNo;
+        added[aadharId]=true;
     }
     function checkDetails()public personPresent view returns(string[6] memory){
         Details memory person = list[msg.sender];