import {z} from 'zod'

export type GetApiUsageArgs = {period?: string | undefined, timezone?: string | undefined};

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

export const usagePeriod = z.object({start: z.string(), end: z.string()});

export const emailCounts = z.object({sent: z.number().int(), delivered: z.number().int(), soft_failed: z.number().int(), hard_failed: z.number().int(), bounced: z.number().int(), held: z.number().int()});

export const emailRates = z.object({delivery_rate: z.number(), bounce_rate: z.number()});

export const apiMeta = z.object({requestId: z.string()});

export const orgUsageSummaryResponse = z.object({success: z.literal(true), data: z.object({period: usagePeriod, emails: emailCounts, rates: emailRates, tenants: z.object({total: z.number().int(), active: z.number().int(), withActivity: z.number().int()})}), meta: apiMeta});

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 org-wide usage summary
 * 
 * GET /usage
 */
export const getApiUsage = async (args: GetApiUsageArgs, options?: GetApiUsageOptions) => {
const {baseUrl = "https://api.arkhq.io/v1", fetch: fetchFn = fetch, apiKey} = options ?? {}

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

if (args.period != null) query.append("period", String(args.period))
if (args.timezone != null) query.append("timezone", String(args.timezone))
if (apiKey !== undefined) headers.set('authorization', `Bearer ${apiKey}`)

const url = `${baseUrl.replace(/\/+$/, '')}/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(orgUsageSummaryResponse, await res.json())
};