import type { Abi, Address } from 'abitype'

import type { Client } from '../../clients/createClient.js'
import type { Transport } from '../../clients/transports/createTransport.js'
import type { ErrorType } from '../../errors/utils.js'
import type { BlockNumber, BlockTag } from '../../types/block.js'
import type { Chain } from '../../types/chain.js'
import type {
  ContractEventName,
  MaybeExtractEventArgsFromAbi,
} from '../../types/contract.js'
import type { Filter } from '../../types/filter.js'
import type { Hex } from '../../types/misc.js'
import {
  type EncodeEventTopicsErrorType,
  type EncodeEventTopicsParameters,
  encodeEventTopics,
} from '../../utils/abi/encodeEventTopics.js'
import type { RequestErrorType } from '../../utils/buildRequest.js'
import {
  type NumberToHexErrorType,
  numberToHex,
} from '../../utils/encoding/toHex.js'
import { createFilterRequestScope } from '../../utils/filters/createFilterRequestScope.js'

export type CreateContractEventFilterParameters<
  abi extends Abi | readonly unknown[] = Abi,
  eventName extends ContractEventName<abi> | undefined = undefined,
  args extends
    | MaybeExtractEventArgsFromAbi<abi, eventName>
    | undefined = undefined,
  strict extends boolean | undefined = undefined,
  fromBlock extends BlockNumber | BlockTag | undefined = undefined,
  toBlock extends BlockNumber | BlockTag | undefined = undefined,
> = {
  address?: Address | Address[] | undefined
  abi: abi
  eventName?: eventName | ContractEventName<abi> | undefined
  fromBlock?: fromBlock | BlockNumber | BlockTag | undefined
  /**
   * Whether or not the logs must match the indexed/non-indexed arguments in the event ABI item.
   * @default false
   */
  strict?: strict | boolean | undefined
  toBlock?: toBlock | BlockNumber | BlockTag | undefined
} & (undefined extends eventName
  ? {
      args?: undefined
    }
  : MaybeExtractEventArgsFromAbi<abi, eventName> extends infer eventFilterArgs
    ? {
        args?:
          | eventFilterArgs
          | (args extends eventFilterArgs ? args : never)
          | undefined
      }
    : {
        args?: undefined
      })

export type CreateContractEventFilterReturnType<
  abi extends Abi | readonly unknown[] = Abi,
  eventName extends ContractEventName<abi> | undefined = undefined,
  args extends
    | MaybeExtractEventArgsFromAbi<abi, eventName>
    | undefined = undefined,
  strict extends boolean | undefined = undefined,
  fromBlock extends BlockNumber | BlockTag | undefined = undefined,
  toBlock extends BlockNumber | BlockTag | undefined = undefined,
> = Filter<'event', abi, eventName, args, strict, fromBlock, toBlock>

export type CreateContractEventFilterErrorType =
  | EncodeEventTopicsErrorType
  | RequestErrorType
  | NumberToHexErrorType
  | ErrorType

/**
 * Creates a Filter to retrieve event logs that can be used with [`getFilterChanges`](https://viem.sh/docs/actions/public/getFilterChanges) or [`getFilterLogs`](https://viem.sh/docs/actions/public/getFilterLogs).
 *
 * - Docs: https://viem.sh/docs/contract/createContractEventFilter
 *
 * @param client - Client to use
 * @param parameters - {@link CreateContractEventFilterParameters}
 * @returns [`Filter`](https://viem.sh/docs/glossary/types#filter). {@link CreateContractEventFilterReturnType}
 *
 * @example
 * import { createPublicClient, http, parseAbi } from 'viem'
 * import { mainnet } from 'viem/chains'
 * import { createContractEventFilter } from 'viem/contract'
 *
 * const client = createPublicClient({
 *   chain: mainnet,
 *   transport: http(),
 * })
 * const filter = await createContractEventFilter(client, {
 *   abi: parseAbi(['event Transfer(address indexed, address indexed, uint256)']),
 * })
 */
export async function createContractEventFilter<
  chain extends Chain | undefined,
  const abi extends Abi | readonly unknown[],
  eventName extends ContractEventName<abi> | undefined,
  args extends MaybeExtractEventArgsFromAbi<abi, eventName> | undefined,
  strict extends boolean | undefined = undefined,
  fromBlock extends BlockNumber | BlockTag | undefined = undefined,
  toBlock extends BlockNumber | BlockTag | undefined = undefined,
>(
  client: Client<Transport, chain>,
  parameters: CreateContractEventFilterParameters<
    abi,
    eventName,
    args,
    strict,
    fromBlock,
    toBlock
  >,
): Promise<
  CreateContractEventFilterReturnType<
    abi,
    eventName,
    args,
    strict,
    fromBlock,
    toBlock
  >
> {
  const { address, abi, args, eventName, fromBlock, strict, toBlock } =
    parameters as CreateContractEventFilterParameters

  const getRequest = createFilterRequestScope(client, {
    method: 'eth_newFilter',
  })

  const topics = eventName
    ? encodeEventTopics({
        abi,
        args,
        eventName,
      } as unknown as EncodeEventTopicsParameters)
    : undefined
  const id: Hex = await client.request({
    method: 'eth_newFilter',
    params: [
      {
        address,
        fromBlock:
          typeof fromBlock === 'bigint' ? numberToHex(fromBlock) : fromBlock,
        toBlock: typeof toBlock === 'bigint' ? numberToHex(toBlock) : toBlock,
        topics,
      },
    ],
  })

  return {
    abi,
    args,
    eventName,
    id,
    request: getRequest(id),
    strict: Boolean(strict),
    type: 'event',
  } as unknown as CreateContractEventFilterReturnType<
    abi,
    eventName,
    args,
    strict,
    fromBlock,
    toBlock
  >
}