import {z} from 'zod'

export type GetApiApiTasksRegressionArgs = {beta_start: string, lookback_seconds?: number | undefined};

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

export const getApiApiTasksRegressionResponse = z.object({metric_definitions: z.object({}).optional(), params: z.object({beta_start: z.number().int().optional(), lookback_seconds: z.number().int().optional()}).optional(), windows: z.object({baseline: z.object({}).optional(), post: z.object({}).optional()}).optional(), deltas: z.object({p95_latency_seconds: z.number().nullable().optional(), intervention_rate: z.number().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
};

/**
 * Get task regression metrics
 * 
 * GET /api/tasks/regression
 * 
 * Also accepts auth: apiKey
 */
export const getApiApiTasksRegression = async (args: GetApiApiTasksRegressionArgs, options: GetApiApiTasksRegressionOptions) => {
const {baseUrl, fetch: fetchFn = fetch, sessionCookie} = options ?? {}

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

if (args.beta_start != null) query.append("beta_start", String(args.beta_start))
if (args.lookback_seconds != null) query.append("lookback_seconds", String(args.lookback_seconds))
if (sessionCookie !== undefined) cookies.push("__Host-mc-session=" + encodeURIComponent(sessionCookie))

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