import {z} from 'zod'

export type GetApiServersIdMetricsArgs = {id: string, names: Array<string>, from?: string | undefined, to?: string | undefined, resolution?: number | undefined, summarize?: boolean | undefined};

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

export const timestamp = z.string();

export const metricValues = z.array(z.number());

export const metricSummary = z.number();

export const multiMetrics = z.array(z.object({name: z.string().optional(), href: z.string().optional(), metrics: z.union([metricValues, metricSummary]).optional()}));

export const metrics = z.object({from: timestamp, to: timestamp, resolution: z.number().int(), metrics: z.record(z.string(), z.union([metricValues, metricSummary, multiMetrics]))});

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 metrics for a server
 * 
 * GET /servers/{id}/metrics
 */
export const getApiServersIdMetrics = async (args: GetApiServersIdMetricsArgs, options?: GetApiServersIdMetricsOptions) => {
const {baseUrl = "https://api.webscale.com/v2", fetch: fetchFn = fetch} = options ?? {}

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

for (const item of args.names ?? []) query.append("names", String(item))
if (args.from != null) query.append("from", String(args.from))
if (args.to != null) query.append("to", String(args.to))
if (args.resolution != null) query.append("resolution", String(args.resolution))
if (args.summarize != null) query.append("summarize", String(args.summarize))

const url = `${baseUrl.replace(/\/+$/, '')}/servers/${encodeURIComponent(String(args.id))}/metrics${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(metrics, await res.json())
};