import * as AbiParameters from '../core/AbiParameters.js'
import type * as Address from '../core/Address.js'
import type * as Authorization from '../core/Authorization.js'
import type * as Errors from '../core/Errors.js'
import * as Hash from '../core/Hash.js'
import * as Hex from '../core/Hex.js'
import type { Assign, Compute, OneOf } from '../core/internal/types.js'
import * as Signature from '../core/Signature.js'
import * as TypedData from '../core/TypedData.js'
import type * as EntryPoint from './EntryPoint.js'

/** User Operation. */
export type UserOperation<
  entryPointVersion extends EntryPoint.Version = EntryPoint.Version,
  signed extends boolean = boolean,
  bigintType = bigint,
  numberType = number,
> = OneOf<
  | (entryPointVersion extends '0.6' ? V06<signed, bigintType> : never)
  | (entryPointVersion extends '0.7' ? V07<signed, bigintType> : never)
  | (entryPointVersion extends '0.8'
      ? V08<signed, bigintType, numberType>
      : never)
>

/**
 * Packed User Operation.
 *
 * @see https://eips.ethereum.org/EIPS/eip-4337#entrypoint-definition
 */
export type Packed = {
  /** Concatenation of `verificationGasLimit` (16 bytes) and `callGasLimit` (16 bytes) */
  accountGasLimits: Hex.Hex
  /** The data to pass to the `sender` during the main execution call. */
  callData: Hex.Hex
  /** Concatenation of `factory` and `factoryData`. */
  initCode: Hex.Hex
  /** Concatenation of `maxPriorityFee` (16 bytes) and `maxFeePerGas` (16 bytes) */
  gasFees: Hex.Hex
  /** Anti-replay parameter. */
  nonce: bigint
  /** Concatenation of paymaster fields (or empty). */
  paymasterAndData: Hex.Hex
  /** Extra gas to pay the Bundler. */
  preVerificationGas: bigint
  /** The account making the operation. */
  sender: Address.Address
  /** Data passed into the account to verify authorization. */
  signature: Hex.Hex
}

/** RPC User Operation type. */
export type Rpc<
  entryPointVersion extends EntryPoint.Version = EntryPoint.Version,
  signed extends boolean = true,
> = OneOf<
  | (entryPointVersion extends '0.6' ? V06<signed, Hex.Hex> : never)
  | (entryPointVersion extends '0.7' ? V07<signed, Hex.Hex> : never)
  | (entryPointVersion extends '0.8' ? V08<signed, Hex.Hex, Hex.Hex> : never)
>

/** Transaction Info. */
export type TransactionInfo<
  entryPointVersion extends EntryPoint.Version = EntryPoint.Version,
  bigintType = bigint,
> = {
  blockHash: Hex.Hex
  blockNumber: bigintType
  entryPoint: Address.Address
  transactionHash: Hex.Hex
  userOperation: UserOperation<entryPointVersion, true, bigintType>
}

/** RPC Transaction Info. */
export type RpcTransactionInfo<
  entryPointVersion extends EntryPoint.Version = EntryPoint.Version,
> = TransactionInfo<entryPointVersion, Hex.Hex>

/** Type for User Operation on EntryPoint 0.6 */
export type V06<signed extends boolean = boolean, bigintType = bigint> = {
  /** The data to pass to the `sender` during the main execution call. */
  callData: Hex.Hex
  /** The amount of gas to allocate the main execution call */
  callGasLimit: bigintType
  /** Account init code. Only for new accounts. */
  initCode?: Hex.Hex | undefined
  /** Maximum fee per gas. */
  maxFeePerGas: bigintType
  /** Maximum priority fee per gas. */
  maxPriorityFeePerGas: bigintType
  /** Anti-replay parameter. */
  nonce: bigintType
  /** Paymaster address with calldata. */
  paymasterAndData?: Hex.Hex | undefined
  /** Extra gas to pay the Bundler. */
  preVerificationGas: bigintType
  /** The account making the operation. */
  sender: Address.Address
  /** Data passed into the account to verify authorization. */
  signature?: Hex.Hex | undefined
  /** The amount of gas to allocate for the verification step. */
  verificationGasLimit: bigintType
} & (signed extends true ? { signature: Hex.Hex } : {})

/** RPC User Operation on EntryPoint 0.6 */
export type RpcV06<signed extends boolean = true> = V06<signed, Hex.Hex>

/** Type for User Operation on EntryPoint 0.7 */
export type V07<signed extends boolean = boolean, bigintType = bigint> = {
  /** The data to pass to the `sender` during the main execution call. */
  callData: Hex.Hex
  /** The amount of gas to allocate the main execution call */
  callGasLimit: bigintType
  /** Account factory. Only for new accounts. */
  factory?: Address.Address | undefined
  /** Data for account factory. */
  factoryData?: Hex.Hex | undefined
  /** Maximum fee per gas. */
  maxFeePerGas: bigintType
  /** Maximum priority fee per gas. */
  maxPriorityFeePerGas: bigintType
  /** Anti-replay parameter. */
  nonce: bigintType
  /** Address of paymaster contract. */
  paymaster?: Address.Address | undefined
  /** Data for paymaster. */
  paymasterData?: Hex.Hex | undefined
  /** The amount of gas to allocate for the paymaster post-operation code. */
  paymasterPostOpGasLimit?: bigintType | undefined
  /** The amount of gas to allocate for the paymaster validation code. */
  paymasterVerificationGasLimit?: bigintType | undefined
  /** Extra gas to pay the Bundler. */
  preVerificationGas: bigintType
  /** The account making the operation. */
  sender: Address.Address
  /** Data passed into the account to verify authorization. */
  signature?: Hex.Hex | undefined
  /** The amount of gas to allocate for the verification step. */
  verificationGasLimit: bigintType
} & (signed extends true ? { signature: Hex.Hex } : {})

/** RPC User Operation on EntryPoint 0.7 */
export type RpcV07<signed extends boolean = true> = V07<signed, Hex.Hex>

/** Type for User Operation on EntryPoint 0.8 */
export type V08<
  signed extends boolean = boolean,
  bigintType = bigint,
  numberType = number,
> = {
  /** Authorization data. */
  authorization?: Authorization.Signed<bigintType, numberType> | undefined
  /** The data to pass to the `sender` during the main execution call. */
  callData: Hex.Hex
  /** The amount of gas to allocate the main execution call */
  callGasLimit: bigintType
  /** Account factory. Only for new accounts. */
  factory?: Address.Address | undefined
  /** Data for account factory. */
  factoryData?: Hex.Hex | undefined
  /** Maximum fee per gas. */
  maxFeePerGas: bigintType
  /** Maximum priority fee per gas. */
  maxPriorityFeePerGas: bigintType
  /** Anti-replay parameter. */
  nonce: bigintType
  /** Address of paymaster contract. */
  paymaster?: Address.Address | undefined
  /** Data for paymaster. */
  paymasterData?: Hex.Hex | undefined
  /** The amount of gas to allocate for the paymaster post-operation code. */
  paymasterPostOpGasLimit?: bigintType | undefined
  /** The amount of gas to allocate for the paymaster validation code. */
  paymasterVerificationGasLimit?: bigintType | undefined
  /** Extra gas to pay the Bundler. */
  preVerificationGas: bigintType
  /** The account making the operation. */
  sender: Address.Address
  /** Data passed into the account to verify authorization. */
  signature?: Hex.Hex | undefined
  /** The amount of gas to allocate for the verification step. */
  verificationGasLimit: bigintType
} & (signed extends true ? { signature: Hex.Hex } : {})

/** RPC User Operation on EntryPoint 0.8 */
export type RpcV08<signed extends boolean = true> = V08<
  signed,
  Hex.Hex,
  Hex.Hex
>

/**
 * Instantiates a {@link ox#UserOperation.UserOperation} from a provided input.
 *
 * @example
 * ```ts twoslash
 * import { Value } from 'ox'
 * import { UserOperation } from 'ox/erc4337'
 *
 * const userOperation = UserOperation.from({
 *   callData: '0xdeadbeef',
 *   callGasLimit: 300_000n,
 *   maxFeePerGas: Value.fromGwei('20'),
 *   maxPriorityFeePerGas: Value.fromGwei('2'),
 *   nonce: 69n,
 *   preVerificationGas: 100_000n,
 *   sender: '0x9f1fdab6458c5fc642fa0f4c5af7473c46837357',
 *   verificationGasLimit: 100_000n,
 * })
 * ```
 *
 * @example
 * ### From Packed User Operation
 *
 * ```ts twoslash
 * import { UserOperation } from 'ox/erc4337'
 *
 * const packed: UserOperation.Packed = {
 *   accountGasLimits: '0x...',
 *   callData: '0xdeadbeef',
 *   initCode: '0x',
 *   gasFees: '0x...',
 *   nonce: 69n,
 *   paymasterAndData: '0x',
 *   preVerificationGas: 100_000n,
 *   sender: '0x9f1fdab6458c5fc642fa0f4c5af7473c46837357',
 *   signature: '0x',
 * }
 *
 * const userOperation = UserOperation.from(packed)
 * ```
 *
 * @example
 * ### Attaching Signatures
 *
 * ```ts twoslash
 * import { Secp256k1, Value } from 'ox'
 * import { UserOperation } from 'ox/erc4337'
 *
 * const userOperation = UserOperation.from({
 *   callData: '0xdeadbeef',
 *   callGasLimit: 300_000n,
 *   maxFeePerGas: Value.fromGwei('20'),
 *   maxPriorityFeePerGas: Value.fromGwei('2'),
 *   nonce: 69n,
 *   preVerificationGas: 100_000n,
 *   sender: '0x9f1fdab6458c5fc642fa0f4c5af7473c46837357',
 *   verificationGasLimit: 100_000n,
 * })
 *
 * const payload = UserOperation.getSignPayload(userOperation, {
 *   chainId: 1,
 *   entryPointAddress: '0x1234567890123456789012345678901234567890',
 *   entryPointVersion: '0.7',
 * })
 *
 * const signature = Secp256k1.sign({ payload, privateKey: '0x...' })
 *
 * const userOperation_signed = UserOperation.from(userOperation, { signature }) // [!code focus]
 * ```
 *
 * @param userOperation - The user operation to instantiate (structured or packed format).
 * @returns User Operation.
 */
export function from<
  const userOperation extends UserOperation | Packed,
  const signature extends Hex.Hex | undefined = undefined,
>(
  userOperation: userOperation | UserOperation | Packed,
  options: from.Options<signature> = {},
): from.ReturnType<userOperation, signature> {
  const signature = (() => {
    if (typeof options.signature === 'string') return options.signature
    if (typeof options.signature === 'object')
      return Signature.toHex(options.signature)
    if (userOperation.signature) return userOperation.signature
    return undefined
  })()

  const packed =
    'accountGasLimits' in userOperation && 'gasFees' in userOperation

  const userOp = packed ? fromPacked(userOperation) : userOperation
  return { ...userOp, signature } as never
}

export declare namespace from {
  export type Options<
    signature extends Signature.Signature | Hex.Hex | undefined = undefined,
  > = {
    signature?: signature | Signature.Signature | Hex.Hex | undefined
  }

  export type ReturnType<
    userOperation extends UserOperation | Packed = UserOperation | Packed,
    signature extends Signature.Signature | Hex.Hex | undefined = undefined,
  > = Compute<
    Assign<
      userOperation,
      signature extends Signature.Signature | Hex.Hex
        ? Readonly<{ signature: Hex.Hex }>
        : {}
    >
  >

  export type ErrorType = Errors.GlobalErrorType
}

/**
 * Converts an {@link ox#UserOperation.Rpc} to an {@link ox#UserOperation.UserOperation}.
 *
 * @example
 * ```ts twoslash
 * import { UserOperation } from 'ox/erc4337'
 *
 * const userOperation = UserOperation.fromRpc({
 *   callData: '0xdeadbeef',
 *   callGasLimit: '0x69420',
 *   maxFeePerGas: '0x2ca6ae494',
 *   maxPriorityFeePerGas: '0x41cc3c0',
 *   nonce: '0x357',
 *   preVerificationGas: '0x69420',
 *   signature: '0x',
 *   sender: '0x1234567890123456789012345678901234567890',
 *   verificationGasLimit: '0x69420',
 * })
 * ```
 *
 * @param rpc - The RPC user operation to convert.
 * @returns An instantiated {@link ox#UserOperation.UserOperation}.
 */
export function fromRpc(rpc: Rpc): UserOperation {
  return {
    ...rpc,
    callGasLimit: BigInt(rpc.callGasLimit),
    maxFeePerGas: BigInt(rpc.maxFeePerGas),
    maxPriorityFeePerGas: BigInt(rpc.maxPriorityFeePerGas),
    nonce: BigInt(rpc.nonce),
    preVerificationGas: BigInt(rpc.preVerificationGas),
    verificationGasLimit: BigInt(rpc.verificationGasLimit),
    ...(rpc.paymasterPostOpGasLimit && {
      paymasterPostOpGasLimit: BigInt(rpc.paymasterPostOpGasLimit),
    }),
    ...(rpc.paymasterVerificationGasLimit && {
      paymasterVerificationGasLimit: BigInt(rpc.paymasterVerificationGasLimit),
    }),
  } as UserOperation
}

export declare namespace fromRpc {
  type ErrorType = Errors.GlobalErrorType
}

/**
 * Obtains the signing payload for a {@link ox#UserOperation.UserOperation}.
 *
 * @example
 * ```ts twoslash
 * import { Secp256k1, Value } from 'ox'
 * import { UserOperation } from 'ox/erc4337'
 *
 * const userOperation = UserOperation.from({
 *   callData: '0xdeadbeef',
 *   callGasLimit: 300_000n,
 *   maxFeePerGas: Value.fromGwei('20'),
 *   maxPriorityFeePerGas: Value.fromGwei('2'),
 *   nonce: 69n,
 *   preVerificationGas: 100_000n,
 *   sender: '0x9f1fdab6458c5fc642fa0f4c5af7473c46837357',
 *   verificationGasLimit: 100_000n,
 * })
 *
 * const payload = UserOperation.getSignPayload(userOperation, { // [!code focus]
 *   chainId: 1, // [!code focus]
 *   entryPointAddress: '0x1234567890123456789012345678901234567890', // [!code focus]
 *   entryPointVersion: '0.6', // [!code focus]
 * }) // [!code focus]
 *
 * const signature = Secp256k1.sign({ payload, privateKey: '0x...' })
 * ```
 *
 * @param userOperation - The user operation to get the sign payload for.
 * @returns The signing payload for the user operation.
 */
export function getSignPayload<
  entrypointVersion extends EntryPoint.Version = EntryPoint.Version,
>(
  userOperation: UserOperation<entrypointVersion>,
  options: getSignPayload.Options<entrypointVersion>,
): Hex.Hex {
  return hash(userOperation, options)
}

export declare namespace getSignPayload {
  type Options<
    entrypointVersion extends EntryPoint.Version = EntryPoint.Version,
  > = hash.Options<entrypointVersion>

  type ErrorType = hash.ErrorType | Errors.GlobalErrorType
}

/**
 * Hashes a {@link ox#UserOperation.UserOperation}. This is the "user operation hash".
 *
 * @example
 * ```ts twoslash
 * import { Value } from 'ox'
 * import { UserOperation } from 'ox/erc4337'
 *
 * const userOperation = UserOperation.hash({
 *   callData: '0xdeadbeef',
 *   callGasLimit: 300_000n,
 *   maxFeePerGas: Value.fromGwei('20'),
 *   maxPriorityFeePerGas: Value.fromGwei('2'),
 *   nonce: 69n,
 *   preVerificationGas: 100_000n,
 *   sender: '0x9f1fdab6458c5fc642fa0f4c5af7473c46837357',
 *   verificationGasLimit: 100_000n,
 * }, {
 *   chainId: 1,
 *   entryPointAddress: '0x1234567890123456789012345678901234567890',
 *   entryPointVersion: '0.6',
 * })
 * ```
 *
 * @param userOperation - The user operation to hash.
 * @returns The hash of the user operation.
 */
export function hash<
  entrypointVersion extends EntryPoint.Version = EntryPoint.Version,
>(
  userOperation: UserOperation<entrypointVersion>,
  options: hash.Options<entrypointVersion>,
): Hex.Hex {
  const { chainId, entryPointAddress, entryPointVersion } = options
  const {
    callData,
    callGasLimit,
    initCode,
    factory,
    factoryData,
    maxFeePerGas,
    maxPriorityFeePerGas,
    nonce,
    paymaster,
    paymasterAndData,
    paymasterData,
    paymasterPostOpGasLimit,
    paymasterVerificationGasLimit,
    preVerificationGas,
    sender,
    verificationGasLimit,
  } = userOperation as UserOperation

  if (entryPointVersion === '0.8') {
    const typedData = toTypedData(userOperation as UserOperation<'0.8', true>, {
      chainId,
      entryPointAddress,
    })
    return TypedData.getSignPayload(typedData)
  }

  const packedUserOp = (() => {
    if (entryPointVersion === '0.6') {
      return AbiParameters.encode(
        [
          { type: 'address' },
          { type: 'uint256' },
          { type: 'bytes32' },
          { type: 'bytes32' },
          { type: 'uint256' },
          { type: 'uint256' },
          { type: 'uint256' },
          { type: 'uint256' },
          { type: 'uint256' },
          { type: 'bytes32' },
        ],
        [
          sender,
          nonce,
          Hash.keccak256(initCode ?? '0x'),
          Hash.keccak256(callData),
          callGasLimit,
          verificationGasLimit,
          preVerificationGas,
          maxFeePerGas,
          maxPriorityFeePerGas,
          Hash.keccak256(paymasterAndData ?? '0x'),
        ],
      )
    }

    if (entryPointVersion === '0.7') {
      const accountGasLimits = Hex.concat(
        Hex.padLeft(Hex.fromNumber(verificationGasLimit), 16),
        Hex.padLeft(Hex.fromNumber(callGasLimit), 16),
      )
      const gasFees = Hex.concat(
        Hex.padLeft(Hex.fromNumber(maxPriorityFeePerGas), 16),
        Hex.padLeft(Hex.fromNumber(maxFeePerGas), 16),
      )
      const initCode_hashed = Hash.keccak256(
        factory && factoryData ? Hex.concat(factory, factoryData) : '0x',
      )
      const paymasterAndData_hashed = Hash.keccak256(
        paymaster
          ? Hex.concat(
              paymaster,
              Hex.padLeft(
                Hex.fromNumber(paymasterVerificationGasLimit || 0),
                16,
              ),
              Hex.padLeft(Hex.fromNumber(paymasterPostOpGasLimit || 0), 16),
              paymasterData || '0x',
            )
          : '0x',
      )

      return AbiParameters.encode(
        [
          { type: 'address' },
          { type: 'uint256' },
          { type: 'bytes32' },
          { type: 'bytes32' },
          { type: 'bytes32' },
          { type: 'uint256' },
          { type: 'bytes32' },
          { type: 'bytes32' },
        ],
        [
          sender,
          nonce,
          initCode_hashed,
          Hash.keccak256(callData),
          accountGasLimits,
          preVerificationGas,
          gasFees,
          paymasterAndData_hashed,
        ],
      )
    }

    throw new Error(`entryPointVersion "${entryPointVersion}" not supported.`)
  })()

  return Hash.keccak256(
    AbiParameters.encode(
      [{ type: 'bytes32' }, { type: 'address' }, { type: 'uint256' }],
      [Hash.keccak256(packedUserOp), entryPointAddress, BigInt(chainId)],
    ),
  )
}

export declare namespace hash {
  type Options<
    entrypointVersion extends EntryPoint.Version = EntryPoint.Version,
  > = {
    chainId: number
    entryPointAddress: Address.Address
    entryPointVersion: entrypointVersion | EntryPoint.Version
  }

  type ErrorType =
    | AbiParameters.encode.ErrorType
    | Hash.keccak256.ErrorType
    | Hex.concat.ErrorType
    | Hex.fromNumber.ErrorType
    | Hex.padLeft.ErrorType
    | Errors.GlobalErrorType
}

/**
 * Converts a {@link ox#UserOperation.UserOperation} to `initCode`.
 *
 * @example
 * ```ts twoslash
 * import { Value } from 'ox'
 * import { UserOperation } from 'ox/erc4337'
 *
 * const initCode = UserOperation.toInitCode({
 *   authorization: {
 *     address: '0x9f1fdab6458c5fc642fa0f4c5af7473c46837357',
 *     chainId: 1,
 *     nonce: 69n,
 *     yParity: 0,
 *     r: 1n,
 *     s: 2n,
 *   },
 *   callData: '0xdeadbeef',
 *   callGasLimit: 300_000n,
 *   factory: '0x7702',
 *   factoryData: '0xdeadbeef',
 *   maxFeePerGas: Value.fromGwei('20'),
 *   maxPriorityFeePerGas: Value.fromGwei('2'),
 *   nonce: 69n,
 *   preVerificationGas: 100_000n,
 *   sender: '0x9f1fdab6458c5fc642fa0f4c5af7473c46837357',
 * })
 * ```
 *
 * @param userOperation - The user operation to convert.
 * @returns The init code.
 */
export function toInitCode(userOperation: Partial<UserOperation>): Hex.Hex {
  const { authorization, factory, factoryData } = userOperation
  if (
    factory === '0x7702' ||
    factory === '0x7702000000000000000000000000000000000000'
  ) {
    if (!authorization) return '0x7702000000000000000000000000000000000000'
    const delegation = authorization.address
    return Hex.concat(delegation, factoryData ?? '0x')
  }
  if (!factory) return '0x'
  return Hex.concat(factory, factoryData ?? '0x')
}

/**
 * Transforms a User Operation into "packed" format.
 *
 * @example
 * ```ts twoslash
 * import { Value } from 'ox'
 * import { UserOperation } from 'ox/erc4337'
 *
 * const packed = UserOperation.toPacked({
 *   callData: '0xdeadbeef',
 *   callGasLimit: 300_000n,
 *   maxFeePerGas: Value.fromGwei('20'),
 *   maxPriorityFeePerGas: Value.fromGwei('2'),
 *   nonce: 69n,
 *   preVerificationGas: 100_000n,
 *   sender: '0x9f1fdab6458c5fc642fa0f4c5af7473c46837357',
 *   signature: '0x...',
 *   verificationGasLimit: 100_000n,
 * })
 * ```
 *
 * @param userOperation - The user operation to transform.
 * @returns The packed user operation.
 */
export function toPacked(
  userOperation: UserOperation<'0.7' | '0.8', true>,
): Packed {
  const {
    callGasLimit,
    callData,
    maxPriorityFeePerGas,
    maxFeePerGas,
    nonce,
    paymaster,
    paymasterData,
    paymasterPostOpGasLimit,
    paymasterVerificationGasLimit,
    sender,
    signature,
    verificationGasLimit,
  } = userOperation

  const accountGasLimits = Hex.concat(
    Hex.padLeft(Hex.fromNumber(verificationGasLimit || 0n), 16),
    Hex.padLeft(Hex.fromNumber(callGasLimit || 0n), 16),
  )
  const initCode = toInitCode(userOperation)
  const gasFees = Hex.concat(
    Hex.padLeft(Hex.fromNumber(maxPriorityFeePerGas || 0n), 16),
    Hex.padLeft(Hex.fromNumber(maxFeePerGas || 0n), 16),
  )
  const paymasterAndData = paymaster
    ? Hex.concat(
        paymaster,
        Hex.padLeft(Hex.fromNumber(paymasterVerificationGasLimit || 0n), 16),
        Hex.padLeft(Hex.fromNumber(paymasterPostOpGasLimit || 0n), 16),
        paymasterData || '0x',
      )
    : '0x'
  const preVerificationGas = userOperation.preVerificationGas ?? 0n

  return {
    accountGasLimits,
    callData,
    initCode,
    gasFees,
    nonce,
    paymasterAndData,
    preVerificationGas,
    sender,
    signature,
  }
}

export declare namespace toPacked {
  export type ErrorType = Errors.GlobalErrorType
}

/**
 * Transforms a "packed" User Operation into a structured {@link ox#UserOperation.UserOperation}.
 *
 * @example
 * ```ts twoslash
 * import { UserOperation } from 'ox/erc4337'
 *
 * const packed: UserOperation.Packed = {
 *   accountGasLimits: '0x...',
 *   callData: '0xdeadbeef',
 *   initCode: '0x...',
 *   gasFees: '0x...',
 *   nonce: 69n,
 *   paymasterAndData: '0x',
 *   preVerificationGas: 100_000n,
 *   sender: '0x9f1fdab6458c5fc642fa0f4c5af7473c46837357',
 *   signature: '0x...',
 * }
 *
 * const userOperation = UserOperation.fromPacked(packed)
 * ```
 *
 * @param packed - The packed user operation to transform.
 * @returns The structured user operation.
 */
export function fromPacked(packed: Packed): UserOperation<'0.7' | '0.8', true> {
  const {
    accountGasLimits,
    callData,
    initCode,
    gasFees,
    nonce,
    paymasterAndData,
    preVerificationGas,
    sender,
    signature,
  } = packed

  const verificationGasLimit = BigInt(Hex.slice(accountGasLimits, 0, 16))
  const callGasLimit = BigInt(Hex.slice(accountGasLimits, 16, 32))

  const { factory, factoryData } = (() => {
    if (initCode === '0x') return { factory: undefined, factoryData: undefined }

    const factory = Hex.slice(initCode, 0, 20)
    const factoryData =
      Hex.size(initCode) > 20 ? Hex.slice(initCode, 20) : undefined

    return { factory, factoryData }
  })()

  const maxPriorityFeePerGas = BigInt(Hex.slice(gasFees, 0, 16))
  const maxFeePerGas = BigInt(Hex.slice(gasFees, 16, 32))

  const {
    paymaster,
    paymasterVerificationGasLimit,
    paymasterPostOpGasLimit,
    paymasterData,
  } = (() => {
    if (paymasterAndData === '0x')
      return {
        paymaster: undefined,
        paymasterVerificationGasLimit: undefined,
        paymasterPostOpGasLimit: undefined,
        paymasterData: undefined,
      }

    const paymaster = Hex.slice(paymasterAndData, 0, 20)
    const paymasterVerificationGasLimit = BigInt(
      Hex.slice(paymasterAndData, 20, 36),
    )
    const paymasterPostOpGasLimit = BigInt(Hex.slice(paymasterAndData, 36, 52))
    const paymasterData =
      Hex.size(paymasterAndData) > 52
        ? Hex.slice(paymasterAndData, 52)
        : undefined

    return {
      paymaster,
      paymasterVerificationGasLimit,
      paymasterPostOpGasLimit,
      paymasterData,
    }
  })()

  return {
    callData,
    callGasLimit,
    ...(factory && { factory }),
    ...(factoryData && { factoryData }),
    maxFeePerGas,
    maxPriorityFeePerGas,
    nonce,
    ...(paymaster && { paymaster }),
    ...(paymasterData && { paymasterData }),
    ...(typeof paymasterPostOpGasLimit === 'bigint' && {
      paymasterPostOpGasLimit,
    }),
    ...(typeof paymasterVerificationGasLimit === 'bigint' && {
      paymasterVerificationGasLimit,
    }),
    preVerificationGas,
    sender,
    signature,
    verificationGasLimit,
  }
}

export declare namespace fromPacked {
  export type ErrorType = Hex.slice.ErrorType | Errors.GlobalErrorType
}

/**
 * Converts a {@link ox#UserOperation.UserOperation} to a {@link ox#UserOperation.Rpc}.
 *
 * @example
 * ```ts twoslash
 * import { Value } from 'ox'
 * import { UserOperation } from 'ox/erc4337'
 *
 * const userOperation = UserOperation.toRpc({
 *   callData: '0xdeadbeef',
 *   callGasLimit: 300_000n,
 *   maxFeePerGas: Value.fromGwei('20'),
 *   maxPriorityFeePerGas: Value.fromGwei('2'),
 *   nonce: 69n,
 *   preVerificationGas: 100_000n,
 *   sender: '0x9f1fdab6458c5fc642fa0f4c5af7473c46837357',
 *   verificationGasLimit: 100_000n,
 * })
 * ```
 *
 * @param userOperation - The user operation to convert.
 * @returns An RPC-formatted user operation.
 */
export function toRpc(userOperation: UserOperation): Rpc {
  const rpc = {} as Rpc

  rpc.callData = userOperation.callData
  rpc.callGasLimit = Hex.fromNumber(userOperation.callGasLimit)
  rpc.maxFeePerGas = Hex.fromNumber(userOperation.maxFeePerGas)
  rpc.maxPriorityFeePerGas = Hex.fromNumber(userOperation.maxPriorityFeePerGas)
  rpc.nonce = Hex.fromNumber(userOperation.nonce)
  rpc.preVerificationGas = Hex.fromNumber(userOperation.preVerificationGas)
  rpc.sender = userOperation.sender
  rpc.verificationGasLimit = Hex.fromNumber(userOperation.verificationGasLimit)

  if (userOperation.factory) rpc.factory = userOperation.factory
  if (userOperation.factoryData) rpc.factoryData = userOperation.factoryData
  if (userOperation.initCode) rpc.initCode = userOperation.initCode
  if (userOperation.paymaster) rpc.paymaster = userOperation.paymaster
  if (userOperation.paymasterData)
    rpc.paymasterData = userOperation.paymasterData
  if (typeof userOperation.paymasterPostOpGasLimit === 'bigint')
    rpc.paymasterPostOpGasLimit = Hex.fromNumber(
      userOperation.paymasterPostOpGasLimit,
    )
  if (typeof userOperation.paymasterVerificationGasLimit === 'bigint')
    rpc.paymasterVerificationGasLimit = Hex.fromNumber(
      userOperation.paymasterVerificationGasLimit,
    )
  if (userOperation.signature) rpc.signature = userOperation.signature

  return rpc
}

export declare namespace toRpc {
  export type ErrorType = Hex.fromNumber.ErrorType | Errors.GlobalErrorType
}

/**
 * Converts a signed {@link ox#UserOperation.UserOperation} to a {@link ox#TypedData.Definition}.
 *
 * @example
 * ```ts twoslash
 * import { Value } from 'ox'
 * import { UserOperation } from 'ox/erc4337'
 *
 * const typedData = UserOperation.toTypedData({
 *   authorization: {
 *     chainId: 1,
 *     address: '0x9f1fdab6458c5fc642fa0f4c5af7473c46837357',
 *     nonce: 69n,
 *     yParity: 0,
 *     r: 1n,
 *     s: 2n,
 *   },
 *   callData: '0xdeadbeef',
 *   callGasLimit: 300_000n,
 *   maxFeePerGas: Value.fromGwei('20'),
 *   maxPriorityFeePerGas: Value.fromGwei('2'),
 *   nonce: 69n,
 *   preVerificationGas: 100_000n,
 *   sender: '0x9f1fdab6458c5fc642fa0f4c5af7473c46837357',
 *   signature: '0x...',
 *   verificationGasLimit: 100_000n,
 * }, {
 *   chainId: 1,
 *   entryPointAddress: '0x1234567890123456789012345678901234567890',
 * })
 * ```
 *
 * @param userOperation - The user operation to convert.
 * @returns A Typed Data definition.
 */
export function toTypedData(
  userOperation: UserOperation<'0.8', true>,
  options: toTypedData.Options,
): TypedData.Definition<typeof toTypedData.types, 'PackedUserOperation'> {
  const { chainId, entryPointAddress } = options

  const packedUserOp = toPacked(userOperation)

  return {
    domain: {
      name: 'ERC4337',
      version: '1',
      chainId,
      verifyingContract: entryPointAddress,
    },
    message: packedUserOp,
    primaryType: 'PackedUserOperation',
    types: toTypedData.types,
  }
}

export namespace toTypedData {
  export type Options = {
    chainId: number
    entryPointAddress: Address.Address
  }

  export type ErrorType = Errors.GlobalErrorType

  export const types = {
    PackedUserOperation: [
      { type: 'address', name: 'sender' },
      { type: 'uint256', name: 'nonce' },
      { type: 'bytes', name: 'initCode' },
      { type: 'bytes', name: 'callData' },
      { type: 'bytes32', name: 'accountGasLimits' },
      { type: 'uint256', name: 'preVerificationGas' },
      { type: 'bytes32', name: 'gasFees' },
      { type: 'bytes', name: 'paymasterAndData' },
    ],
  } as const
}
