import {z} from 'zod'

export type GetApiResourcesPreviewArgs = {'ev-api-key': string, 'ev-access-token': string, resource: string, size: 'small' | 'medium' | 'large', width?: number | undefined, height?: number | undefined, page?: number | undefined};

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

export const previewFile = z.object({id: z.number().int().optional(), type: z.string().optional(), attributes: z.object({image: z.string().optional(), size: z.number().int().optional(), imageHash: z.string().optional(), pageCount: z.number().int().optional()}).optional()});

export const previewFileResponse = z.object({responseStatus: z.number().int().optional(), data: previewFile.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
};

/**
 * Preview a file
 * 
 * GET /resources/preview
 */
export const getApiResourcesPreview = async (args: GetApiResourcesPreviewArgs, options?: GetApiResourcesPreviewOptions) => {
const {baseUrl = "https://accountname.exavault.com/api/v2", fetch: fetchFn = fetch} = options ?? {}

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

if (args['ev-api-key'] != null) headers.set("ev-api-key", String(args['ev-api-key']))
if (args['ev-access-token'] != null) headers.set("ev-access-token", String(args['ev-access-token']))
if (args.resource != null) query.append("resource", String(args.resource))
if (args.size != null) query.append("size", String(args.size))
if (args.width != null) query.append("width", String(args.width))
if (args.height != null) query.append("height", String(args.height))
if (args.page != null) query.append("page", String(args.page))

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