import {z} from 'zod'

export type GetApiV2CdnExperimentsArgs = {cv?: number | undefined, token: string};

export type GetApiV2CdnExperimentsOptions = {baseUrl?: string | undefined, ApiKeyAuth?: string | undefined, fetch?: typeof fetch | undefined};

export const experimentVariant = z.object({name: z.string(), display_name: z.string(), public_id: z.string(), weight: z.number().int(), is_control: z.boolean(), story_mappings: z.array(z.object({original_story_id: z.number().int(), original_slug: z.string().nullable(), variant_story_id: z.number().int().nullable(), variant_slug: z.string().nullable()}))});

export const experiment = z.object({id: z.number().int(), name: z.string(), display_name: z.string(), story_ids: z.array(z.number().int()), variants: z.array(experimentVariant), stories: z.array(z.object({id: z.number().int(), full_slug: z.string()}))});

export const getApiV2CdnExperimentsResponse = z.object({experiments: z.array(experiment), cv: z.number().int().nullable().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
};

/**
 * Retrieve Running Experiments
 * 
 * GET /v2/cdn/experiments
 */
export const getApiV2CdnExperiments = async (args: GetApiV2CdnExperimentsArgs, options?: GetApiV2CdnExperimentsOptions) => {
const {baseUrl = "https://api.storyblok.com", fetch: fetchFn = fetch, ApiKeyAuth} = options ?? {}

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

if (args.cv != null) query.append("cv", String(args.cv))
if (args.token != null) query.append("token", String(args.token))
if (ApiKeyAuth !== undefined) query.set("token", ApiKeyAuth)

const url = `${baseUrl.replace(/\/+$/, '')}/v2/cdn/experiments${query.size > 0 ? `?${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(getApiV2CdnExperimentsResponse, await res.json())
};