// SPDX-License-Identifier: GPL-3.0

pragma solidity >=0.7.0 <0.9.0;

import "https://github.com/openzeppelin/openzeppelin-contracts/contracts/token/ERC20/IERC20.sol";

contract DequestJackpot {
    
    address private owner;
    uint8 private tokenIndex;
    mapping(uint8 => address) public idToToken;
    mapping(uint8 => address) public idToSigner;
    mapping(address => uint8) public tokenToId;
    mapping(address => uint256) public request;
    
    event Claim(uint8 _tokenIndex, address indexed _receiver, uint256 indexed _index, uint256 _amount);
    
    constructor() {
        owner = msg.sender;
    }
    
    function changeOwner(address _owner) external returns (bool) {
        require(msg.sender == owner, "DequestJackpot: Invalid owner");
        owner = _owner;
        return true;
    }
    
    function changeSigner(uint8 _index, address _signer) external returns (bool) {
        require(msg.sender == owner, "DequestJackpot: Invalid owner");
        idToSigner[_index] = _signer;
        return true;
    }
    
    function addToken(address _tokenAddress, address _signer) external returns (bool) {
        require(msg.sender == owner, "DequestJackpot: Invalid owner");
        idToSigner[tokenIndex] = _signer;
        idToToken[tokenIndex] = _tokenAddress;
        tokenToId[_tokenAddress] = tokenIndex;
        ++tokenIndex;
        return true;
    }
    
    function claim(uint8 tIndex, uint256 amount, uint8 v, bytes32 r, bytes32 s) external returns (bool) {
        require(idToSigner[tIndex] != address(0x0), "DequestJackpot: Invalid index");
        require(idToToken[tIndex] != address(0x0), "DequestJackpot: Invalid token");
        
        address sender  = msg.sender;
        bytes32 message = keccak256(abi.encodePacked("\x19Ethereum Signed Message:\n32", keccak256(abi.encode(tIndex, sender, request[sender], amount))));
        
        require(ecrecover(message, v, r, s) == idToSigner[tIndex], "DequestJackpot: Invalid signer");
        
        IERC20 token = IERC20(idToToken[tIndex]);
        
        token.transfer(sender, amount);
        
        emit Claim(tIndex, sender, request[sender], amount);
        
        ++request[sender];
        
        return true;
    }
}

{
  "compilationTarget": {
    "contracts/DequestJackpot.sol": "DequestJackpot"
  },
  "evmVersion": "berlin",
  "libraries": {},
  "metadata": {
    "bytecodeHash": "ipfs"
  },
  "optimizer": {
    "enabled": true,
    "runs": 200
  },
  "remappings": []
}