import {z} from 'zod'

export type GetApiTemplatesFieldsArgs = {Accept: string, 'Content-Type': 'application/json'};

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

export const getApiTemplatesFieldsResponse = z.object({fields: z.array(z.object({data_type: z.enum(["boolean", "integer", "float", "string", "datetime", "url"]).optional(), default_value: z.string().nullable().optional(), description: z.string().nullable().optional(), domain_name: z.object({order: z.number().int().optional(), summary: z.string().optional()}).optional(), example: z.string().nullable().optional(), keyword: z.string().nullable().optional(), summary: z.string().optional(), type: z.enum(["standard_field", "custom_field"]).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
};

/**
 * List template fields
 * 
 * GET /templates/fields
 */
export const getApiTemplatesFields = async (args: GetApiTemplatesFieldsArgs, options?: GetApiTemplatesFieldsOptions) => {
const {baseUrl = "https://api.pagerduty.com", fetch: fetchFn = fetch, apiKey} = options ?? {}

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

if (args.Accept != null) headers.set("Accept", String(args.Accept))
if (args['Content-Type'] != null) headers.set("Content-Type", String(args['Content-Type']))
if (apiKey !== undefined) headers.set("Authorization", apiKey)

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