import {z} from 'zod'

export type GetApiSyncArgs = {since?: number | undefined, limit?: number | undefined};

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

export const syncEvent = z.object({seq: z.number().int().optional(), type: z.enum(["message.new", "message.edit", "message.delete", "conversation.create", "conversation.update", "conversation.archive", "participant.add", "participant.remove"]).optional(), data: z.object({}).optional(), conversationId: z.string().optional(), at: z.string().optional()});

export const getApiSyncResponse = z.object({ok: z.boolean().optional(), data: z.object({events: z.array(syncEvent).optional(), cursor: z.number().int().optional(), hasMore: z.boolean().optional()}).optional()});

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
};

/**
 * 增量同步（轮询）
 * 
 * GET /sync
 */
export const getApiSync = async (args: GetApiSyncArgs, options?: GetApiSyncOptions) => {
const {baseUrl = "http://localhost:3200/api", fetch: fetchFn = fetch, bearerAuth} = options ?? {}

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

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

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