// SPDX-License-Identifier: MIT
pragma solidity ^0.8.24;

/**
 * @title ERC1967Proxy
 * @notice Minimal ERC-1967 proxy. All calls (except construction) are delegated
 *         to the implementation stored in the EIP-1967 slot.
 *
 * Deploy flow for FomoMinerBibiUpgradeable:
 *   1. Deploy `FomoMinerBibiUpgradeable` (logic / implementation)
 *   2. Encode `initialize(token, poolClaimer, owner, listPrices)` calldata
 *   3. Deploy `ERC1967Proxy(implementation, initCalldata)`
 *   4. Players / front-end always use the **Proxy** address
 *   5. To ship a new version: deploy new implementation, then call
 *      `upgradeTo(newImpl)` or `upgradeToAndCall(newImpl, data)` on the Proxy
 *      (as `owner`)
 */
contract ERC1967Proxy {
    // keccak256("eip1967.proxy.implementation") - 1
    bytes32 private constant _IMPLEMENTATION_SLOT =
        0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;

    error ProxyDelegateFailed();

    constructor(address implementation_, bytes memory data_) {
        require(implementation_ != address(0), "ZERO_IMPL");
        require(implementation_.code.length > 0, "NOT_CONTRACT");
        assembly {
            sstore(_IMPLEMENTATION_SLOT, implementation_)
        }
        if (data_.length > 0) {
            (bool ok, bytes memory ret) = implementation_.delegatecall(data_);
            if (!ok) {
                if (ret.length == 0) revert ProxyDelegateFailed();
                assembly {
                    revert(add(ret, 32), mload(ret))
                }
            }
        }
    }

    fallback() external payable {
        _delegate();
    }

    receive() external payable {
        _delegate();
    }

    function _delegate() private {
        assembly {
            let impl := sload(_IMPLEMENTATION_SLOT)
            calldatacopy(0, 0, calldatasize())
            let result := delegatecall(gas(), impl, 0, calldatasize(), 0, 0)
            returndatacopy(0, 0, returndatasize())
            switch result
            case 0 { revert(0, returndatasize()) }
            default { return(0, returndatasize()) }
        }
    }
}