// SPDX-License-Identifier: MIT
pragma solidity ^0.8.13;

import "../listing-terms-registry/IListingTermsRegistry.sol";

library ListingStrategies {
    bytes4 public constant FIXED_RATE = bytes4(keccak256("FIXED_RATE"));
    bytes4 public constant FIXED_RATE_WITH_REWARD = bytes4(keccak256("FIXED_RATE_WITH_REWARD"));

    /**
     * @dev Thrown when the listing strategy ID does not match the required one.
     * @param provided Provided listing strategy ID.
     * @param required Required listing strategy ID.
     */
    error ListingStrategyMismatch(bytes4 provided, bytes4 required);

    /**
     * @dev Modifier to check strategy compatibility.
     */
    modifier compatibleStrategy(bytes4 checkedStrategyId, bytes4 expectedStrategyId) {
        if (checkedStrategyId != expectedStrategyId)
            revert ListingStrategyMismatch(checkedStrategyId, expectedStrategyId);
        _;
    }

    function getSupportedListingStrategyIDs() internal pure returns (bytes4[] memory supportedListingStrategyIDs) {
        bytes4[] memory supportedListingStrategies = new bytes4[](2);
        supportedListingStrategies[0] = FIXED_RATE;
        supportedListingStrategies[1] = FIXED_RATE_WITH_REWARD;
        return supportedListingStrategies;
    }

    function isValidListingStrategy(bytes4 listingStrategyId) internal pure returns (bool) {
        return listingStrategyId == FIXED_RATE || listingStrategyId == FIXED_RATE_WITH_REWARD;
    }

    function decodeFixedRateListingStrategyParams(IListingTermsRegistry.ListingTerms memory terms)
        internal
        pure
        compatibleStrategy(terms.strategyId, FIXED_RATE)
        returns (uint256 baseRate)
    {
        return abi.decode(terms.strategyData, (uint256));
    }

    function decodeFixedRateWithRewardListingStrategyParams(IListingTermsRegistry.ListingTerms memory terms)
        internal
        pure
        compatibleStrategy(terms.strategyId, FIXED_RATE_WITH_REWARD)
        returns (uint256 baseRate, uint16 rewardPercentage)
    {
        return abi.decode(terms.strategyData, (uint256, uint16));
    }
}