near-ca-test/dist/esm/utils/mock-sign.js

An SDK for controlling Ethereum Accounts from a Near Account.

import { privateKeyToAccount } from "viem/accounts";
import { fromPayload, nearAccountFromAccountId, NearEthAdapter, } from "..";
/**
 * Converts a raw hexadecimal signature into a structured Signature object
 * @param hexSignature The raw hexadecimal signature (e.g., '0x...')
 * @returns A structured Signature object with fields r, s, v, and yParity
 */
function hexToSignature(hexSignature) {
    // Strip "0x" prefix if it exists
    const cleanedHex = hexSignature.slice(2);
    // Ensure the signature is 65 bytes (130 hex characters)
    if (cleanedHex.length !== 130) {
        throw new Error(`Invalid hex signature length: ${cleanedHex.length}. Expected 130 characters (65 bytes).`);
    }
    // Extract the r, s, and v components from the hex signature
    const v = BigInt(`0x${cleanedHex.slice(128, 130)}`); // Last byte (2 hex characters)
    return {
        r: `0x${cleanedHex.slice(0, 64)}`, // First 32 bytes (64 hex characters)
        s: `0x${cleanedHex.slice(64, 128)}`, // Next 32 bytes (64 hex characters),
        v,
        // Determine yParity based on v (27 or 28 maps to 0 or 1)
        yParity: v === 27n ? 0 : v === 28n ? 1 : undefined,
    };
}
export class MockMpcContract {
    connectedAccount;
    ethAccount;
    constructor(account, privateKey) {
        this.connectedAccount = account;
        this.ethAccount = privateKeyToAccount(privateKey ||
            // Known key from deterministic ganache client
            "0x4f3edf983ac636a65a842ce7c78d9aa706d3b113bce9c46f30d7d21715b23b1d");
    }
    accountId() {
        return "mock-mpc.offline";
    }
    deriveEthAddress = async (_unused) => {
        return this.ethAccount.address;
    };
    getDeposit = async () => {
        return "1";
    };
    requestSignature = async (signArgs, _gas) => {
        const hexSignature = await this.ethAccount.sign({
            hash: fromPayload(signArgs.payload),
        });
        return hexToSignature(hexSignature);
    };
    async encodeSignatureRequestTx(signArgs, gas) {
        return {
            signerId: this.connectedAccount.accountId,
            receiverId: this.accountId(),
            actions: [
                {
                    type: "FunctionCall",
                    params: {
                        methodName: "sign",
                        args: { request: signArgs },
                        gas: gas ? gas.toString() : "1",
                        deposit: await this.getDeposit(),
                    },
                },
            ],
        };
    }
}
export async function mockAdapter(privateKey) {
    const account = await nearAccountFromAccountId("mock-user.offline", {
        networkId: "testnet",
        nodeUrl: "https://rpc.testnet.near.org",
    });
    const mpcContract = new MockMpcContract(account, privateKey);
    return NearEthAdapter.fromConfig({ mpcContract });
}