import {z} from 'zod'

export type GetApiOfferingDegreesDegreeIdArgs = {degreeId: string, year?: string | undefined};

export type GetApiOfferingDegreesDegreeIdOptions = {baseUrl?: string | undefined, BearerAuth?: string | undefined, fetch?: typeof fetch | undefined};

export const offeringCourseOverview = z.object({name: z.string(), shortcode: z.string(), cfu: z.number().int(), teachingYear: z.number().int(), language: z.enum(["it", "en"]), group: z.string().nullable()});

export const track = z.object({id: z.number(), name: z.string(), courses: z.array(offeringCourseOverview)});

export const degree = z.object({id: z.string(), name: z.string(), level: z.string(), department: z.object({name: z.string()}), faculty: z.object({id: z.string().optional(), name: z.string().optional()}), location: z.string(), duration: z.string(), class: z.object({code: z.string(), name: z.string()}), year: z.number(), editions: z.array(z.string()), notes: z.array(z.string()), objectives: z.object({title: z.string(), content: z.string()}), jobOpportunities: z.object({title: z.string(), content: z.string()}), tracks: z.array(track)});

export const getApiOfferingDegreesDegreeIdResponse = z.object({data: degree});

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
};

/**
 * Show a degree | Mostra un corso di laurea
 * 
 * GET /offering/degrees/{degreeId}
 */
export const getApiOfferingDegreesDegreeId = async (args: GetApiOfferingDegreesDegreeIdArgs, options?: GetApiOfferingDegreesDegreeIdOptions) => {
const {baseUrl = "https://app.didattica.polito.it/api", fetch: fetchFn = fetch, BearerAuth} = options ?? {}

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

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

const url = `${baseUrl.replace(/\/+$/, '')}/offering/degrees/${encodeURIComponent(String(args.degreeId))}${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(getApiOfferingDegreesDegreeIdResponse, await res.json())
};