import type {
    Chain,
    Client,
    SignMessageParameters,
    SignMessageReturnType,
    Transport
} from "viem"
import type { SmartAccount } from "viem/account-abstraction"
import { parseAccount } from "viem/utils"
import { AccountNotFoundError } from "../../errors/index.js"

/**
 * Calculates an Ethereum-specific signature in [EIP-191 format](https://eips.ethereum.org/EIPS/eip-191): `keccak256("\x19Ethereum Signed Message:\n" + len(message) + message))`.
 *
 * - Docs: https://viem.sh/docs/actions/wallet/signMessage.html
 * - JSON-RPC Methods:
 *   - JSON-RPC Accounts: [`personal_sign`](https://docs.metamask.io/guide/signing-data.html#personal-sign)
 *   - Local Accounts: Signs locally. No JSON-RPC request.
 *
 * With the calculated signature, you can:
 * - use [`verifyMessage`](https://viem.sh/docs/utilities/verifyMessage.html) to verify the signature,
 * - use [`recoverMessageAddress`](https://viem.sh/docs/utilities/recoverMessageAddress.html) to recover the signing address from a signature.
 *
 * @param client - Client to use
 * @param parameters - {@link SignMessageParameters}
 * @returns The signed message. {@link SignMessageReturnType}
 *
 * @example
 * import { createWalletClient, custom } from 'viem'
 * import { mainnet } from 'viem/chains'
 * import { signMessage } from 'viem/wallet'
 *
 * const client = createWalletClient({
 *   chain: mainnet,
 *   transport: custom(window.ethereum),
 * })
 * const signature = await signMessage(client, {
 *   account: '0xA0Cf798816D4b9b9866b5330EEa46a18382f251e',
 *   message: 'hello world',
 * })
 *
 * @example
 * // Account Hoisting
 * import { createWalletClient, custom } from 'viem'
 * import { privateKeyToAccount } from 'viem/accounts'
 * import { mainnet } from 'viem/chains'
 * import { signMessage } from 'viem/wallet'
 *
 * const client = createWalletClient({
 *   account: privateKeyToAccount('0x…'),
 *   chain: mainnet,
 *   transport: custom(window.ethereum),
 * })
 * const signature = await signMessage(client, {
 *   message: 'hello world',
 * })
 */
export async function signMessage<TAccount extends SmartAccount | undefined>(
    client: Client<Transport, Chain | undefined, TAccount>,
    {
        account: account_ = client.account,
        message
    }: SignMessageParameters<TAccount>
): Promise<SignMessageReturnType> {
    if (!account_)
        throw new AccountNotFoundError({
            docsPath: "/docs/actions/wallet/signMessage"
        })

    const account = parseAccount(account_) as SmartAccount

    return account.signMessage({ message })
}