// SPDX-License-Identifier: UNLICENSED
// Proprietary - (c) 2026 Durian (durianfun). All rights reserved. Not open source; for Durianfun + authorized integrations only. See /LICENSE.
pragma solidity 0.8.24;

import "../EntropyConsumer.sol";
import "../EntropyLib.sol";

/// @title  RouletteConsumer
/// @notice Example: a single-signature European roulette spin (0..36), keeper-free. No real money in
///         this demo (it records the pocket) — it pairs with dumb-roulette/index.html. Each spin pays
///         the protocol fee and self-cranks the previous spin so results land without a 2nd user tx.
///
///         A REAL money roulette must escrow the stake at spin() time, pay out in _onRandomness,
///         forfeit on expiry, and CAP the aggregate stake per block (see CoinFlipHouse + plan).
contract RouletteConsumer is EntropyConsumer {
    using EntropyLib for uint256;

    uint32 public constant CB_GAS = 120_000;

    mapping(uint256 => address) public spinner;
    mapping(uint256 => uint8)   public pocketOf; // 37 = unsettled
    uint256 private _nonce;
    uint256 private _lastPending = type(uint256).max;

    event SpinRequested(uint256 indexed id, address indexed player);
    event SpinResult(uint256 indexed id, address indexed player, uint8 pocket, bool red);

    constructor(address e) EntropyConsumer(e) {}

    function spin() external payable {
        uint256 f = entropy.fee(CB_GAS);
        require(msg.value >= f, "fee");
        if (_lastPending != type(uint256).max) _tryReveal(_lastPending);
        bytes32 seed = keccak256(abi.encodePacked(msg.sender, block.number, _nonce++));
        uint256 id = _roll(seed, CB_GAS);
        spinner[id] = msg.sender;
        pocketOf[id] = 37;
        _lastPending = id;
        emit SpinRequested(id, msg.sender);
        if (msg.value > f) {
            (bool ok, ) = msg.sender.call{value: msg.value - f}(""); // refund overpay
            require(ok, "refund failed");
        }
    }

    function _onRandomness(uint256 id, uint256 rng) internal override {
        address p = spinner[id];
        delete spinner[id];
        uint8 pocket = uint8(rng.pick(0, 37));
        pocketOf[id] = pocket;
        emit SpinResult(id, p, pocket, _isRed(pocket));
    }

    function _isRed(uint8 n) private pure returns (bool) {
        if (n == 0) return false;
        uint256 redMask = 0x154AAD52AA; // bit n => red, verified for n in 1..36
        return (redMask >> n) & 1 == 1;
    }
}