import {z} from 'zod'

export type GetApiTemplatesVariablesArgs = {type?: string | undefined, category?: string | undefined};

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

export const templateVariableDto = z.object({name: z.string().optional(), tag: z.string().optional(), label: z.string().optional(), description: z.string().optional(), types: z.array(z.string()).optional(), sampleValue: z.string().nullable().optional(), categories: z.array(z.string()).nullable().optional(), smsSafe: z.boolean().optional()});

export const getApiTemplatesVariablesResponse = z.array(templateVariableDto);

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
};

/**
 * The backend-owned template variable catalog: every {{token}} the render
 * pipeline knows, with label, description, applicable template types, and
 * the sample value previews use. The editor's variable picker and
 * autocomplete derive from this.
 * 
 * GET /templates/variables
 */
export const getApiTemplatesVariables = async (args: GetApiTemplatesVariablesArgs, options?: GetApiTemplatesVariablesOptions) => {
const {baseUrl = "https://api.clinicos.vet/backend/business", fetch: fetchFn = fetch, Bearer} = options ?? {}

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

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

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