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rajan-31/landRegistry.sol

Last active August 29, 2021 15:26
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  1. rajan-31 revised this gist Aug 29, 2021. 1 changed file with 1 addition and 0 deletions.
    1 change: 1 addition & 0 deletions landRegistry.sol
    View file
    Original file line number Diff line number Diff line change
    @@ -102,6 +102,7 @@ contract landRecords {
    bytes32 serveyNoInB32 = stringToBytes32(_serveyNo);
    Land memory temp = lands[serveyNoInB32];
    require(temp.owner == msg.sender, "You are not the OWNER!");
    require(temp.isVerified == true, "Land is not verified!");
    // make land available for sale
    lands[serveyNoInB32].availableForSale = true;
    }
  2. rajan-31 created this gist May 25, 2021.
    170 changes: 170 additions & 0 deletions landRegistry.sol
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,170 @@
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.7.0 < 0.9.0;
    contract landRecords {
    struct Admin {
    string name;
    string district;
    }
    struct User {
    string name;
    string docHash;
    string district;
    bool isVerified;
    }
    struct Land {
    string serveyNo;
    string location;
    uint area;
    uint purchaseEpoch;
    address owner;
    string district;
    bool isVerified;
    bool availableForSale;
    }

    struct LandSell {
    string serveyNo;
    address owner;
    address buyer;
    uint price;
    bool sellerApproval;
    bool adminApproval;
    }

    mapping(address => Admin) public admins;
    mapping(address => User) public users;
    mapping(bytes32 => Land) public lands;
    // all districtwise sells
    mapping(string => LandSell[]) public allSells;

    address superAdmin;

    constructor() {
    // store address of superAdmin when contract is deployed
    superAdmin = msg.sender;
    }

    function compareStrings(string memory str1, string memory str2) private pure returns(bool) {
    return(keccak256(bytes(str1)) == keccak256(bytes(str2)));
    }

    function stringToBytes32(string memory source) public pure returns (bytes32 result) {
    bytes memory tempEmptyStringTest = bytes(source);
    if (tempEmptyStringTest.length == 0) {
    return 0x0;
    }
    assembly {
    result := mload(add(source, 32))
    }
    }

    function createModifyAdmin(address _address, string memory _name, string memory _district) public {
    // if superAdmin is accessing function he can add/overwrite exiting data
    require(msg.sender == superAdmin, "Unauthorized User!");
    admins[_address] = Admin(_name, _district);
    }

    function regUser(string memory _name, string memory _docHash, string memory _district) public {
    User memory temp = users[msg.sender];
    // if account is not verified then only create account/ change data
    require(temp.isVerified == false, "User Already Exists!");
    users[msg.sender] = User(_name, _docHash, _district, false);
    }

    function modifyUser(address _address, string memory _name, string memory _docHash, string memory _district, bool _isVerified) public {
    Admin memory temp = admins[msg.sender];
    // 1) check if admin exist (if admin exists then district also exits) 2) is he admin of same district
    // *make sure that user can't able to set null/ empty value for district
    require(compareStrings(temp.district, _district), "Unauthorized Admin!");
    users[_address] = User(_name, _docHash, _district, _isVerified);
    }

    function regLand(string memory _serveyNo, string memory _location, uint _area, uint _purchaseEpoch, string memory _district) public {
    bytes32 serveyNoInB32 = stringToBytes32(_serveyNo);
    Land memory temp = lands[serveyNoInB32];
    User memory temp2 = users[msg.sender];
    // if land is not verified then only register/change data
    require(temp.isVerified == false && temp2.isVerified == true, "Land with given servey No. is already registered and verified!");
    // *make sure that user can't able to set null/ empty value for district
    lands[serveyNoInB32] = Land(_serveyNo, _location, _area, _purchaseEpoch, msg.sender, _district, false, false);
    }

    function modifyLand(string memory _serveyNo, string memory _location, uint _area, uint _purchaseEpoch, bool _isVerified) public {
    bytes32 serveyNoInB32 = stringToBytes32(_serveyNo);
    Admin memory temp = admins[msg.sender];
    Land memory temp2 = lands[serveyNoInB32];
    require(compareStrings(temp.district, temp2.district), "Unauthorized Admin!");
    // admin can change everything except owner, district, availableForSale (this is intentional behaviour)
    lands[serveyNoInB32] = Land(_serveyNo, _location, _area, _purchaseEpoch, temp2.owner, temp2.district, _isVerified, temp2.availableForSale);
    }

    function makeAvailable(string memory _serveyNo) public {
    bytes32 serveyNoInB32 = stringToBytes32(_serveyNo);
    Land memory temp = lands[serveyNoInB32];
    require(temp.owner == msg.sender, "You are not the OWNER!");
    // make land available for sale
    lands[serveyNoInB32].availableForSale = true;
    }

    function cancelAvailable(string memory _serveyNo) public {
    bytes32 serveyNoInB32 = stringToBytes32(_serveyNo);
    Land memory temp = lands[serveyNoInB32];
    require(temp.owner == msg.sender, "You are not the OWNER!");
    // cancel availability of land for sale
    lands[serveyNoInB32].availableForSale = false;
    }

    function requestToBuy(string memory _serveyNo, uint _price) public{
    bytes32 serveyNoInB32 = stringToBytes32(_serveyNo);
    Land memory temp = lands[serveyNoInB32];
    require(lands[serveyNoInB32].availableForSale == true, "Land is not available for purchase!");
    allSells[temp.district].push(LandSell(_serveyNo, temp.owner, msg.sender, _price, false, false));
    lands[serveyNoInB32].availableForSale = false;
    }

    function approveSell(string memory _serveyNo) public {
    bytes32 serveyNoInB32 = stringToBytes32(_serveyNo);
    Land memory temp = lands[serveyNoInB32];
    require(temp.owner == msg.sender, "You are not the OWNER!");
    LandSell[] memory districtSells = allSells[temp.district];
    uint i=0;
    for(;i<districtSells.length; i++){
    if(compareStrings(districtSells[i].serveyNo, _serveyNo)){
    break;
    }
    }
    allSells[temp.district][i].sellerApproval = true;
    }

    function approveAdmin(string memory _serveyNo) public {
    bytes32 serveyNoInB32 = stringToBytes32(_serveyNo);
    Admin memory temp = admins[msg.sender];
    Land memory temp2 = lands[serveyNoInB32];
    require(compareStrings(temp.district, temp2.district), "Unauthorized Admin!");
    LandSell[] memory districtSells = allSells[temp.district];
    uint i=0;
    for(;i<districtSells.length; i++){
    if(compareStrings(districtSells[i].serveyNo, _serveyNo)){
    break;
    }
    }
    allSells[temp.district][i].adminApproval = true;
    }

    function confirmSell(string memory _serveyNo) public {
    bytes32 serveyNoInB32 = stringToBytes32(_serveyNo);
    Land memory temp = lands[serveyNoInB32];
    require(temp.owner == msg.sender, "You are not the OWNER!");
    LandSell[] memory districtSells = allSells[temp.district];
    uint i=0;
    for(;i<districtSells.length; i++){
    if(compareStrings(districtSells[i].serveyNo, _serveyNo)){
    break;
    }
    }
    require(allSells[temp.district][i].adminApproval == true, "Not Approved by Admin!");
    require(allSells[temp.district][i].sellerApproval == true, "Not Approved by Seller/ You!");
    lands[serveyNoInB32].owner = allSells[temp.district][i].buyer;
    delete allSells[temp.district][i];
    }
    }
    13 changes: 13 additions & 0 deletions stringToBytes32.sol
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,13 @@
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.7.0 < 0.9.0;
    contract converter {
    function stringToBytes32(string memory source) public pure returns (bytes32 result) {
    bytes memory tempEmptyStringTest = bytes(source);
    if (tempEmptyStringTest.length == 0) {
    return 0x0;
    }
    assembly {
    result := mload(add(source, 32))
    }
    }
    }