import {z} from 'zod'

export type GetApiApiUsageArgs = {api_key?: (string | null) | undefined, 'x-api-key'?: (string | null) | undefined};

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

export const aPIUsageLimits = z.object({api_rows_returned_limit: z.number().int(), api_requests_limit: z.number().int(), api_rows_per_response_limit: z.number().int(), per_second_api_rate_limit: z.number().int(), per_minute_api_rate_limit: z.number().int(), per_hour_api_rate_limit: z.number().int()});

export const currentPeriodUsage = z.object({total_requests: z.number().int(), total_api_rows_returned: z.number().int()});

export const aPIUsageResponse = z.object({plan_name: z.string(), limits: aPIUsageLimits, current_usage_period_start: z.string(), current_usage_period_end: z.string(), current_period_usage: currentPeriodUsage});

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 Api Usage Endpoint
 * 
 * GET /api_usage
 */
export const getApiApiUsage = async (args: GetApiApiUsageArgs, options?: GetApiApiUsageOptions) => {
const {baseUrl = "https://api.gridstatus.io/v1", fetch: fetchFn = fetch} = options ?? {}

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

if (args.api_key != null) query.append("api_key", String(args.api_key))
if (args['x-api-key'] != null) headers.set("x-api-key", String(args['x-api-key']))

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