import {z} from 'zod'

export type GetApiMealplannerGenerateArgs = {timeFrame?: string | undefined, targetCalories?: number | undefined, diet?: string | undefined, exclude?: string | undefined};

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

export const getApiMealplannerGenerateResponse = z.object({meals: z.array(z.object({id: z.number().int(), title: z.string().min(1), imageType: z.string().min(1), readyInMinutes: z.number().int(), servings: z.number(), sourceUrl: z.string().min(1)})), nutrients: z.object({calories: z.number(), carbohydrates: z.number(), fat: z.number(), protein: z.number()})});

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
};

/**
 * Generate Meal Plan
 * 
 * GET /mealplanner/generate
 */
export const getApiMealplannerGenerate = async (args: GetApiMealplannerGenerateArgs, options?: GetApiMealplannerGenerateOptions) => {
const {baseUrl = "https://api.spoonacular.com", fetch: fetchFn = fetch, apiKeyScheme} = options ?? {}

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

if (args.timeFrame != null) query.append("timeFrame", String(args.timeFrame))
if (args.targetCalories != null) query.append("targetCalories", String(args.targetCalories))
if (args.diet != null) query.append("diet", String(args.diet))
if (args.exclude != null) query.append("exclude", String(args.exclude))
if (apiKeyScheme !== undefined) headers.set("x-api-key", apiKeyScheme)

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