import {z} from 'zod'

export type GetApiV1FilesArgs = {purpose?: ('batch' | 'batch_output' | 'batch_error') | undefined, limit?: string | undefined, after?: string | undefined};

export type GetApiV1FilesOptions = {baseUrl?: string | undefined, bearerAuth?: string | undefined, fetch?: typeof fetch | undefined};

export const batchFile = z.object({id: z.string(), object: z.literal("file"), bytes: z.number(), created_at: z.number(), expires_at: z.number().nullable(), filename: z.string(), purpose: z.enum(["batch", "batch_output", "batch_error"]), status: z.literal("processed"), status_details: z.unknown()});

export const getApiV1FilesResponse = z.object({object: z.literal("list"), data: z.array(batchFile), first_id: z.string().nullable(), last_id: z.string().nullable(), has_more: z.boolean()});

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
};

/**
 * List files
 * 
 * GET /v1/files
 */
export const getApiV1Files = async (args: GetApiV1FilesArgs, options?: GetApiV1FilesOptions) => {
const {baseUrl = "https://api.llmgateway.io", fetch: fetchFn = fetch, bearerAuth} = options ?? {}

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

if (args.purpose != null) query.append("purpose", String(args.purpose))
if (args.limit != null) query.append("limit", String(args.limit))
if (args.after != null) query.append("after", String(args.after))
if (bearerAuth !== undefined) headers.set('authorization', `Bearer ${bearerAuth}`)

const url = `${baseUrl.replace(/\/+$/, '')}/v1/files${query.size > 0 ? `?${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(getApiV1FilesResponse, await res.json())
};