import {z} from 'zod'

export type GetApiSmartContractsArgs = {q?: string | undefined, filter?: string | undefined};

export type GetApiSmartContractsOptions = {baseUrl?: string | undefined, fetch?: typeof fetch | undefined};

export const addressTag = z.object({address_hash: z.string(), display_name: z.string(), label: z.string()});

export const watchlistName = z.object({display_name: z.string(), label: z.string()});

export const addressParam = z.object({hash: z.string(), implementation_name: z.string(), name: z.string(), ens_domain_name: z.string().optional(), metadata: z.object({}).optional(), is_contract: z.boolean(), private_tags: z.array(addressTag), watchlist_names: z.array(watchlistName), public_tags: z.array(addressTag), is_verified: z.boolean()});

export const smartContractForList = z.object({address_hash: addressParam.optional(), coin_balance: z.string(), compiler_version: z.string(), language: z.string(), has_constructor_args: z.boolean(), optimization_enabled: z.boolean(), transactions_count: z.number().int().optional(), verified_at: z.string(), market_cap: z.number().optional()});

export const getApiSmartContractsResponse = z.object({items: z.array(smartContractForList), next_page_params: z.object({})});

export const validateResponse = async <Output>(
  schema: {
    readonly '~standard': {
      readonly validate: (value: unknown) => ({ readonly value: Output; readonly issues?: undefined } | { readonly issues: ReadonlyArray<{ readonly message: string; readonly path?: ReadonlyArray<PropertyKey | { readonly key: PropertyKey }> | undefined }> }) | Promise<{ readonly value: Output; readonly issues?: undefined } | { readonly issues: ReadonlyArray<{ readonly message: string; readonly path?: ReadonlyArray<PropertyKey | { readonly key: PropertyKey }> | undefined }> }>
    }
  },
  value: unknown
): Promise<Output> => {
  const result = await schema['~standard'].validate(value)

  if (result.issues !== undefined) {
    const detail = result.issues
      .map(({ message, path }) =>
        path?.length
          ? `${path.map((segment) => String(typeof segment === 'object' ? segment.key : segment)).join('.')}: ${message}`
          : message
      )
      .join('; ')

    throw new Error(`Response does not match the schema: ${detail}`, { cause: { issues: result.issues } })
  }

  return result.value
};

/**
 * get verified smart contracts
 * 
 * GET /smart-contracts
 */
export const getApiSmartContracts = async (args: GetApiSmartContractsArgs, options?: GetApiSmartContractsOptions) => {
const {baseUrl = "https://eth.blockscout.com/api/v2", fetch: fetchFn = fetch} = options ?? {}

const query = new URLSearchParams()
const headers = new Headers()
headers.set('accept', "application/json")

if (args.q != null) query.append("q", String(args.q))
if (args.filter != null) query.append("filter", String(args.filter))

const url = `${baseUrl.replace(/\/+$/, '')}/smart-contracts${query.size > 0 ? `?${query}` : ''}`

const res = await fetchFn(url, {method: "GET", headers})

if (!res.ok) throw new Error(`Request failed with status ${res.status}`, {cause: {status: res.status, body: await res.text()}})

return validateResponse(getApiSmartContractsResponse, await res.json())
};