import {z} from 'zod'

export type GetApiV3UnitsOptions = {baseUrl?: string | undefined, bearerAuth?: string | undefined, fetch?: typeof fetch | undefined};

export const conversionStep = z.object({operation: z.enum(["ADD", "MULTIPLY"]), value: z.number()});

export const unitCategory = z.object({id: z.number().int().optional(), name: z.string(), standardUnitAbbreviatedName: z.string().optional()});

export const unit = z.object({abbreviatedName: z.string(), advanced: z.number().int().optional(), category: z.enum(["Distance", "Duration", "Energy", "Frequency", "Miscellany", "Pressure", "Proportion", "Rating", "Temperature", "Volume", "Weight", "Count"]), categoryId: z.number().int().optional(), categoryName: z.string().optional(), conversionSteps: z.array(conversionStep), id: z.number().int().optional(), manualTracking: z.number().int().optional(), maximumAllowedValue: z.number().optional(), maximumValue: z.number().int(), minimumAllowedValue: z.number().optional(), minimumValue: z.number().int().optional(), name: z.string(), unitCategory: unitCategory});

export const getApiV3UnitsResponse = z.array(unit);

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 units
 * 
 * GET /v3/units
 * 
 * Also accepts auth: curedao_oauth2
 */
export const getApiV3Units = async (options?: GetApiV3UnitsOptions) => {
const {baseUrl = "https://app.quantimo.do/api", fetch: fetchFn = fetch, bearerAuth} = options ?? {}

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

if (bearerAuth !== undefined) headers.set('authorization', `Bearer ${bearerAuth}`)

const url = `${baseUrl.replace(/\/+$/, '')}/v3/units${query.size > 0 ? `?${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(getApiV3UnitsResponse, await res.json())
};