// SPDX-License-Identifier: MIT
pragma solidity ^0.8.29;

import {EnumerableSetLib} from "solady/utils/EnumerableSetLib.sol";

struct Subscription {
    uint256 tokenId; // 32 bytes
    uint256 spent; // 32 bytes
    address space; // 20 bytes
    uint40 installTime; // 5 bytes - when subscription was first installed
    uint40 lastRenewalTime; // 5 bytes
    uint40 nextRenewalTime; // 5 bytes
    bool active; // 1 byte
    uint64 duration; // 8 bytes
    uint256 lastKnownRenewalPrice; // 32 bytes
    uint256 lastKnownExpiresAt; // 32 bytes
    address lastKnownCurrency; // 20 bytes - currency at install/sync time
}

struct OperatorConfig {
    uint256 interval;
    uint256 buffer;
}

library SubscriptionModuleStorage {
    using EnumerableSetLib for EnumerableSetLib.Uint256Set;
    using EnumerableSetLib for EnumerableSetLib.AddressSet;

    uint256 public constant KEEPER_INTERVAL = 5 minutes;
    uint256 public constant MIN_RENEWAL_BUFFER = KEEPER_INTERVAL + 1 minutes; // Minimum buffer to prevent double renewals

    /// @custom:storage-location erc7201:towns.subscription.validation.module.storage
    struct Layout {
        EnumerableSetLib.AddressSet operators;
        mapping(address account => mapping(uint32 entityId => Subscription)) subscriptions;
        mapping(address account => EnumerableSetLib.Uint256Set entityIds) entityIds;
        mapping(address operator => OperatorConfig) operatorConfig;
        mapping(address account => mapping(address space => uint256 tokenId)) tokenIdByAccountBySpace;
        address spaceFactory;
    }

    // keccak256(abi.encode(uint256(keccak256("towns.subscription.validation.module.storage")) - 1)) & ~bytes32(uint256(0xff))
    bytes32 internal constant STORAGE_SLOT =
        0xd241b3ceee256b40f80fe7a66fe789234ac389ed1408c472c4ee1cbb1deb8600;

    function getLayout() internal pure returns (Layout storage $) {
        assembly {
            $.slot := STORAGE_SLOT
        }
    }

    function getOperatorBuffer(address operator) internal view returns (uint256) {
        OperatorConfig storage config = getLayout().operatorConfig[operator];
        if (config.interval == 0 || config.buffer == 0) return MIN_RENEWAL_BUFFER;
        return config.buffer;
    }
}