Arkie-Library-Frontend/src/wallet/injected.ts

import { requestWalletNonce, verifyWalletSignature } from "./api";

export type WalletKind = "tokenPocket" | "metaMask" | "imToken";

export type EthereumProvider = {
  isMetaMask?: boolean;
  isTokenPocket?: boolean;
  isImToken?: boolean;
  providers?: EthereumProvider[];
  request: <T = unknown>(args: {
    method: string;
    params?: unknown[];
  }) => Promise<T>;
};

export function getInjectedEthereum(): EthereumProvider | null {
  if (typeof window === "undefined") return null;
  const maybeWindow = window as typeof window & { ethereum?: EthereumProvider };
  return maybeWindow.ethereum ?? null;
}

export function getInjectedWallet(kind?: WalletKind): EthereumProvider | null {
  const ethereum = getInjectedEthereum();
  if (!ethereum || !kind) return ethereum;
  const providers = ethereum.providers?.length
    ? ethereum.providers
    : [ethereum];
  const match = providers.find((provider) => {
    if (kind === "metaMask") return provider.isMetaMask;
    if (kind === "tokenPocket") return provider.isTokenPocket;
    if (kind === "imToken") return provider.isImToken;
    return false;
  });
  return match ?? null;
}

export async function signInWithInjectedWallet(kind?: WalletKind): Promise<{
  token: string;
  wallet: string;
}> {
  const ethereum = getInjectedWallet(kind);
  if (!ethereum) throw new Error("No injected wallet found");

  // Login is signature-only (EIP-191 personal_sign). The backend verifies the
  // recovered address and never inspects chainId, so we deliberately do NOT
  // switch or add any chain — that only adds a failure-prone wallet popup.
  const accounts = await ethereum.request<string[]>({
    method: "eth_requestAccounts",
  });
  const address = accounts[0];
  if (!address) throw new Error("No wallet account returned");

  const nonce = await requestWalletNonce(address);
  const signature = await ethereum.request<string>({
    method: "personal_sign",
    params: [nonce.message, address],
  });
  return verifyWalletSignature({
    address,
    message: nonce.message,
    signature,
  });
}