// SPDX-License-Identifier: MIT
pragma solidity ^0.8.19;

/**
 * @title AccountHashing
 * @notice Utilities for hashing account identifiers with salts to protect PII
 */
library AccountHashing {
    /**
     * @notice Generates a hashed account reference ID
     * @param rail The payment rail identifier (e.g., "FEDWIRE", "SEPA")
     * @param countryCode The country code (e.g., "US", "DE")
     * @param accountIdentifier The account identifier (IBAN, ABA, etc.) - should be hashed off-chain
     * @param salt A unique salt for this account
     * @return accountRefId The hashed account reference ID
     */
    function hashAccountRef(
        bytes32 rail,
        bytes32 countryCode,
        bytes32 accountIdentifier,
        bytes32 salt
    ) internal pure returns (bytes32 accountRefId) {
        return keccak256(abi.encodePacked(rail, countryCode, accountIdentifier, salt));
    }

    /**
     * @notice Generates a hashed wallet reference ID
     * @param chainId The chain ID where the wallet exists
     * @param walletAddress The wallet address
     * @param providerId The provider identifier (e.g., "METAMASK", "FIREBLOCKS")
     * @return walletRefId The hashed wallet reference ID
     */
    function hashWalletRef(
        uint256 chainId,
        address walletAddress,
        bytes32 providerId
    ) internal pure returns (bytes32 walletRefId) {
        return keccak256(abi.encodePacked(chainId, walletAddress, providerId));
    }

    /**
     * @notice Generates an ICAN (Internal Canonical Account Number) reference ID
     * @param namespace The internal namespace identifier
     * @param accountId The internal account ID
     * @return icanRefId The ICAN reference ID
     */
    function hashICANRef(bytes32 namespace, bytes32 accountId) internal pure returns (bytes32 icanRefId) {
        return keccak256(abi.encodePacked(namespace, accountId));
    }
}