// SPDX-License-Identifier: MIT
pragma solidity ^0.8.20;

interface IUniswapV2Router {
    function swapExactTokensForTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);
}

contract SellTixDEX {
    IUniswapV2Router public router;
    IERC20 public stxToken;
    IERC20 public maticToken;
    
    constructor(address _router, address _stx, address _matic) {
        router = IUniswapV2Router(_router);
        stxToken = IERC20(_stx);
        maticToken = IERC20(_matic);
    }

    function swapSTXForMatic(uint256 stxAmount) external {
        // User sends STX
        stxToken.transferFrom(msg.sender, address(this), stxAmount);
        
        // Swap STX for MATIC through DEX
        address[] memory path = new address[](2);
        path[0] = address(stxToken);
        path[1] = address(maticToken);
        
        router.swapExactTokensForTokens(
            stxAmount,
            0, // Accept any amount of MATIC
            path,
            msg.sender,
            block.timestamp
        );
    }
}