import {z} from 'zod'

export type GetApiLastUpdatesArgs = {'datasets.limit'?: number | undefined, 'datasets.offset'?: number | undefined, 'providers.limit'?: number | undefined, 'providers.offset'?: number | undefined};

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

export const getApiLastUpdatesResponse = z.object({_meta: z.object({version: z.string()}), datasets: z.object({docs: z.array(z.object({code: z.string(), indexed_at: z.string().optional(), json_data_commit_ref: z.string().optional(), name: z.string().optional(), nb_series: z.number().int().gte(0).optional(), provider_code: z.string().optional(), provider_name: z.string().optional()})), limit: z.number().int(), num_found: z.number().int(), offset: z.number().int()}), providers: z.object({docs: z.array(z.object({code: z.string(), indexed_at: z.string().optional(), name: z.string().optional(), region: z.string().optional(), terms_of_use: z.string().optional(), website: z.string().optional()})), limit: z.number().int(), num_found: z.number().int(), offset: z.number().int()})});

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
};

/**
 * Respond a list of providers and a list of datasets sorted by creation/conversion date, most recent first.
 * 
 * GET /last-updates
 */
export const getApiLastUpdates = async (args: GetApiLastUpdatesArgs, options: GetApiLastUpdatesOptions) => {
const {baseUrl, fetch: fetchFn = fetch} = options ?? {}

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

if (args['datasets.limit'] != null) query.append("datasets.limit", String(args['datasets.limit']))
if (args['datasets.offset'] != null) query.append("datasets.offset", String(args['datasets.offset']))
if (args['providers.limit'] != null) query.append("providers.limit", String(args['providers.limit']))
if (args['providers.offset'] != null) query.append("providers.offset", String(args['providers.offset']))

const url = `${baseUrl.replace(/\/+$/, '')}/last-updates${query.size > 0 ? `?${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(getApiLastUpdatesResponse, await res.json())
};