KaitenToken

[
  {
    "inputs": [
      {
        "internalType": "string",
        "name": "name_",
        "type": "string"
      },
      {
        "internalType": "string",
        "name": "symbol_",
        "type": "string"
      },
      {
        "internalType": "string",
        "name": "imageURI_",
        "type": "string"
      },
      {
        "internalType": "address",
        "name": "creator_",
        "type": "address"
      }
    ],
    "stateMutability": "nonpayable",
    "type": "constructor"
  },
  {
    "inputs": [],
    "name": "AlreadyWired",
    "type": "error"
  },
  {
    "inputs": [],
    "name": "AntiSnipeCap",
    "type": "error"
  },
  {
    "inputs": [
      {
        "internalType": "address",
        "name": "spender",
        "type": "address"
      },
      {
        "internalType": "uint256",
        "name": "allowance",
        "type": "uint256"
      },
      {
        "internalType": "uint256",
        "name": "needed",
        "type": "uint256"
      }
    ],
    "name": "ERC20InsufficientAllowance",
    "type": "error"
  },
  {
    "inputs": [
      {
        "internalType": "address",
        "name": "sender",
        "type": "address"
      },
      {
        "internalType": "uint256",
        "name": "balance",
        "type": "uint256"
      },
      {
        "internalType": "uint256",
        "name": "needed",
        "type": "uint256"
      }
    ],
    "name": "ERC20InsufficientBalance",
    "type": "error"
  },
  {
    "inputs": [
      {
        "internalType": "address",
        "name": "approver",
        "type": "address"
      }
    ],
    "name": "ERC20InvalidApprover",
    "type": "error"
  },
  {
    "inputs": [
      {
        "internalType": "address",
        "name": "receiver",
        "type": "address"
      }
    ],
    "name": "ERC20InvalidReceiver",
    "type": "error"
  },
  {
    "inputs": [
      {
        "internalType": "address",
        "name": "sender",
        "type": "address"
      }
    ],
    "name": "ERC20InvalidSender",
    "type": "error"
  },
  {
    "inputs": [
      {
        "internalType": "address",
        "name": "spender",
        "type": "address"
      }
    ],
    "name": "ERC20InvalidSpender",
    "type": "error"
  },
  {
    "inputs": [],
    "name": "OnlyFactory",
    "type": "error"
  },
  {
    "anonymous": false,
    "inputs": [
      {
        "indexed": true,
        "internalType": "address",
        "name": "owner",
        "type": "address"
      },
      {
        "indexed": true,
        "internalType": "address",
        "name": "spender",
        "type": "address"
      },
      {
        "indexed": false,
        "internalType": "uint256",
        "name": "value",
        "type": "uint256"
      }
    ],
    "name": "Approval",
    "type": "event"
  },
  {
    "anonymous": false,
    "inputs": [
      {
        "indexed": true,
        "internalType": "address",
        "name": "from",
        "type": "address"
      },
      {
        "indexed": true,
        "internalType": "address",
        "name": "to",
        "type": "address"
      },
      {
        "indexed": false,
        "internalType": "uint256",
        "name": "value",
        "type": "uint256"
      }
    ],
    "name": "Transfer",
    "type": "event"
  },
  {
    "inputs": [],
    "name": "MAX_BUY",
    "outputs": [
      {
        "internalType": "uint256",
        "name": "",
        "type": "uint256"
      }
    ],
    "stateMutability": "view",
    "type": "function"
  },
  {
    "inputs": [],
    "name": "SNIPE_WINDOW",
    "outputs": [
      {
        "internalType": "uint256",
        "name": "",
        "type": "uint256"
      }
    ],
    "stateMutability": "view",
    "type": "function"
  },
  {
    "inputs": [],
    "name": "TOTAL_SUPPLY",
    "outputs": [
      {
        "internalType": "uint256",
        "name": "",
        "type": "uint256"
      }
    ],
    "stateMutability": "view",
    "type": "function"
  },
  {
    "inputs": [
      {
        "internalType": "address",
        "name": "owner",
        "type": "address"
      },
      {
        "internalType": "address",
        "name": "spender",
        "type": "address"
      }
    ],
    "name": "allowance",
    "outputs": [
      {
        "internalType": "uint256",
        "name": "",
        "type": "uint256"
      }
    ],
    "stateMutability": "view",
    "type": "function"
  },
  {
    "inputs": [
      {
        "internalType": "address",
        "name": "spender",
        "type": "address"
      },
      {
        "internalType": "uint256",
        "name": "value",
        "type": "uint256"
      }
    ],
    "name": "approve",
    "outputs": [
      {
        "internalType": "bool",
        "name": "",
        "type": "bool"
      }
    ],
    "stateMutability": "nonpayable",
    "type": "function"
  },
  {
    "inputs": [
      {
        "internalType": "address",
        "name": "account",
        "type": "address"
      }
    ],
    "name": "balanceOf",
    "outputs": [
      {
        "internalType": "uint256",
        "name": "",
        "type": "uint256"
      }
    ],
    "stateMutability": "view",
    "type": "function"
  },
  {
    "inputs": [
      {
        "internalType": "address",
        "name": "buyer",
        "type": "address"
      }
    ],
    "name": "boughtInWindow",
    "outputs": [
      {
        "internalType": "uint256",
        "name": "bought",
        "type": "uint256"
      }
    ],
    "stateMutability": "view",
    "type": "function"
  },
  {
    "inputs": [],
    "name": "creator",
    "outputs": [
      {
        "internalType": "address",
        "name": "",
        "type": "address"
      }
    ],
    "stateMutability": "view",
    "type": "function"
  },
  {
    "inputs": [],
    "name": "decimals",
    "outputs": [
      {
        "internalType": "uint8",
        "name": "",
        "type": "uint8"
      }
    ],
    "stateMutability": "view",
    "type": "function"
  },
  {
    "inputs": [],
    "name": "factory",
    "outputs": [
      {
        "internalType": "address",
        "name": "",
        "type": "address"
      }
    ],
    "stateMutability": "view",
    "type": "function"
  },
  {
    "inputs": [],
    "name": "imageURI",
    "outputs": [
      {
        "internalType": "string",
        "name": "",
        "type": "string"
      }
    ],
    "stateMutability": "view",
    "type": "function"
  },
  {
    "inputs": [
      {
        "internalType": "address",
        "name": "pool_",
        "type": "address"
      }
    ],
    "name": "initializeAntiSnipe",
    "outputs": [],
    "stateMutability": "nonpayable",
    "type": "function"
  },
  {
    "inputs": [],
    "name": "name",
    "outputs": [
      {
        "internalType": "string",
        "name": "",
        "type": "string"
      }
    ],
    "stateMutability": "view",
    "type": "function"
  },
  {
    "inputs": [],
    "name": "pool",
    "outputs": [
      {
        "internalType": "address",
        "name": "",
        "type": "address"
      }
    ],
    "stateMutability": "view",
    "type": "function"
  },
  {
    "inputs": [],
    "name": "snipeEndsAt",
    "outputs": [
      {
        "internalType": "uint256",
        "name": "",
        "type": "uint256"
      }
    ],
    "stateMutability": "view",
    "type": "function"
  },
  {
    "inputs": [],
    "name": "symbol",
    "outputs": [
      {
        "internalType": "string",
        "name": "",
        "type": "string"
      }
    ],
    "stateMutability": "view",
    "type": "function"
  },
  {
    "inputs": [],
    "name": "totalSupply",
    "outputs": [
      {
        "internalType": "uint256",
        "name": "",
        "type": "uint256"
      }
    ],
    "stateMutability": "view",
    "type": "function"
  },
  {
    "inputs": [
      {
        "internalType": "address",
        "name": "to",
        "type": "address"
      },
      {
        "internalType": "uint256",
        "name": "value",
        "type": "uint256"
      }
    ],
    "name": "transfer",
    "outputs": [
      {
        "internalType": "bool",
        "name": "",
        "type": "bool"
      }
    ],
    "stateMutability": "nonpayable",
    "type": "function"
  },
  {
    "inputs": [
      {
        "internalType": "address",
        "name": "from",
        "type": "address"
      },
      {
        "internalType": "address",
        "name": "to",
        "type": "address"
      },
      {
        "internalType": "uint256",
        "name": "value",
        "type": "uint256"
      }
    ],
    "name": "transferFrom",
    "outputs": [
      {
        "internalType": "bool",
        "name": "",
        "type": "bool"
      }
    ],
    "stateMutability": "nonpayable",
    "type": "function"
  }
]

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.28;

import { ERC20 } from "@openzeppelin/contracts/token/ERC20/ERC20.sol";

/// @title KaitenToken
/// @notice Fixed-supply ERC20 launched by KaitenFactory. No mint function, no
///         owner. A single anti-snipe rule caps the size of *public buys* (pool
///         -> wallet) for a short window after the pool is created.
/// @dev    Anti-snipe is TIMESTAMP-based on purpose: Robinhood Chain is an
///         Arbitrum Orbit L2 where `block.number` is the parent-chain number and
///         is not a reliable local clock. Cap is PER TRANSACTION (0.5% of supply).
contract KaitenToken is ERC20 {
    uint256 public constant TOTAL_SUPPLY = 100_000_000e18;
    /// @notice max tokens a single non-creator buy may pull from the pool during the window (0.5%).
    uint256 public constant MAX_BUY = TOTAL_SUPPLY / 200; // 500,000 tokens
    uint256 public constant SNIPE_WINDOW = 5 minutes;

    /// @notice the factory that launched this token — exempt, and the only wirer.
    address public immutable factory;
    /// @notice the creator (launcher) — exempt from the buy cap (incl. initial buy).
    address public immutable creator;
    string public imageURI;

    /// @notice the token's V3 pool; set once by the factory at launch.
    address public pool;
    /// @notice timestamp at which the anti-snipe cap stops applying.
    uint256 public snipeEndsAt;
    /// @notice cumulative tokens each recipient has bought FROM the pool during the
    ///         window. The cap is enforced on this running total, so batching many
    ///         sub-cap buys into one tx (or one `multicall`) can't slip past it.
    mapping(address buyer => uint256 bought) public boughtInWindow;

    error OnlyFactory();
    error AlreadyWired();
    error AntiSnipeCap();

    constructor(string memory name_, string memory symbol_, string memory imageURI_, address creator_)
        ERC20(name_, symbol_)
    {
        factory = msg.sender;
        creator = creator_;
        imageURI = imageURI_;
        _mint(msg.sender, TOTAL_SUPPLY); // all supply to the factory; it seeds the LP
    }

    /// @notice One-time wiring by the factory: record the pool and start the 5-min window.
    function initializeAntiSnipe(address pool_) external {
        if (msg.sender != factory) revert OnlyFactory();
        if (pool != address(0)) revert AlreadyWired();
        pool = pool_;
        snipeEndsAt = block.timestamp + SNIPE_WINDOW;
    }

    /// @dev The launch protection. Only *buys* (pool -> recipient) by a non-creator,
    ///      non-factory wallet, within the window, are capped. Sells (to == pool) and
    ///      all wallet-to-wallet transfers are unrestricted. Setup transfers (factory
    ///      seeding the LP) are `to == pool`, so never restricted.
    ///
    ///      The cap is on the recipient's CUMULATIVE buys during the window, not on a
    ///      single transfer: a per-transfer check is trivially defeated by a wrapper
    ///      contract that loops N sub-cap buys in one tx. Cumulative tracking bounds
    ///      what any one address can accumulate. (Splitting across many fresh wallets
    ///      is inherent to any address-based cap and out of scope for this rule.)
    function _update(address from, address to, uint256 value) internal override {
        address _pool = pool;
        if (
            _pool != address(0) && from == _pool && to != creator && to != factory
                && block.timestamp < snipeEndsAt
        ) {
            uint256 bought = boughtInWindow[to] + value;
            if (bought > MAX_BUY) revert AntiSnipeCap();
            boughtInWindow[to] = bought;
        }
        super._update(from, to, value);
    }
}