merkle.sol

pragma solidity ^0.6.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);

    /**
     * @dev Moves `amount` tokens from the caller's account to `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);

    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);

    /**
     * @dev Moves `amount` tokens from `sender` to `recipient` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
}



pragma solidity ^0.6.0;

contract MerkleProof {

    address public owner;
    bytes32 public root;

     constructor() public {
        owner=msg.sender;
    }

    address public distributionWallet=0x15412D1f9C63e9123Fa62a3E385a130f5C959De5;

    IERC20 public mnst;
    bool public claimIsActive = false;

    mapping(address => bool) claimedAddresses;
    
     function flipClaimState() public {
        require(msg.sender==owner, "Only Owner can use this function");
        claimIsActive = !claimIsActive;
    }

    function setPurchaseToken(IERC20 token) public  {
        require(msg.sender==owner, "Only Owner can use this function");
        mnst = token; //Monstr Token
    }

    function setRoot(bytes32 newRoot) public  {
        require(msg.sender==owner, "Only Owner can use this function");
        root=newRoot; //Set Root
    }

     function setDistributionWallet(address newWallet) public {
        require(msg.sender==owner, "Only Owner can use this function");
        distributionWallet=newWallet; //Set Wallet
    }
     function transferOwnership(address newOwner) public {
        require(msg.sender==owner, "Only Owner can use this function");
        owner=newOwner; //Set Owner
    }

    function withdrawStuckMonstrBalance() public {
        require(msg.sender==owner, "Only Owner can use this function");
        mnst.transferFrom(address(this),msg.sender,mnst.balanceOf(address(this)));
    }

    function hasClaimed(address claimedAddress) public view returns (bool){
      return claimedAddresses[claimedAddress]; //check if claimed
    }

    function removeFromClaimed(address claimedAddress) public {
      require(msg.sender==owner, "Only Owner can use this function");
      claimedAddresses[claimedAddress]=false; //only for testing 
    }
 
    
  function verify(
    bytes32 leaf,
    bytes32[] memory proof
  )
    public
    view
    returns (bool)
  {
    bytes32 computedHash = leaf;

    for (uint256 i = 0; i < proof.length; i++) {
      bytes32 proofElement = proof[i];

      if (computedHash < proofElement) {
        // Hash(current computed hash + current element of the proof)
        computedHash = keccak256(abi.encodePacked(computedHash, proofElement));
      } else {
        // Hash(current element of the proof + current computed hash)
        computedHash = keccak256(abi.encodePacked(proofElement, computedHash));
      }
    }

    // Check if the computed hash (root) is equal to the provided root
    return computedHash == root;
  }
  
function claim(bytes32[] memory proof,address account, uint256 amount) public{

    require(claimIsActive, "Claim is not enabled");
    require(!claimedAddresses[account], "MerkleDistributor: Drop already claimed.");
    require(msg.sender==account, "Sender not claimer");

    bytes32 leaf = keccak256(abi.encodePacked(account, amount));
    require(verify(leaf,proof), "Not Eligible");

    mnst.transferFrom(distributionWallet,account,amount*10**9);  //transfer
    claimedAddresses[account]=true;
}
}