Swap for Caller

As we just explained, Flash Swaps can be very difficult to execute. So we've added an easier way to execute swaps through the Swapper, which we call "Swap for Caller". In this case, the swap acts more similar to most AMMs, where there are two steps:

1. Approve the Swapper to use the tokens

2. Execute the swap, where the tokens will be taken from our wallet, and we will receive the other tokens in exchange

pragma solidity >=0.8.7 <0.9.0;

import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
import '@mean-finance/dca-v2-periphery/interfaces/IDCAHubSwapper.sol';

contract MyContract {

    IDCAHubSwapper public immutable swapper;
    
    constructor(IDCAHubSwapper _swapper) {
        swapper = _swapper;
    }

    /// @notice Executes a swap for the caller, by sending them the reward, and taking from them the needed tokens
    /// @param _tokens The tokens involved in the swap
    /// @param _pairsToSwap The pairs to swap
    /// @param _minimumOutput The minimum amount of tokens to receive as part of the swap
    /// @param _maximumInput The maximum amount of tokens to provide as part of the swap
    /// @param _recipient Address that will receive all the tokens from the swap
    /// @param _deadline Deadline when the swap becomes invalid
    /// @return The information about the executed swap
    function swapForCaller(
        address[] calldata _tokens,
        IDCAHub.PairIndexes[] calldata _pairsToSwap,
        uint256[] calldata _minimumOutput,
        uint256[] calldata _maximumInput,
        address _recipient,
        uint256 _deadline
    ) external payable returns (IDCAHub.SwapInfo memory) {
    
      // Step 1, set allowance so that the swapper can take the tokens
      for (uint i; i < _tokens.length; i++) {
        IERC20(_tokens[i]).approve(address(swapper), _maximumInput[i]);
      }

      // Step 2, execute the swap
      return swapper.swapForCaller(_tokens, _pairsToSwap, _minimumOutput, _maximumInput, _recipient, _deadline);
    }
}