import {z} from 'zod'

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

export const placeRef = z.object({buildingId: z.string(), floorId: z.string(), roomId: z.string(), siteId: z.string(), name: z.string()});

export const exam = z.object({id: z.number().int(), courseId: z.number(), courseShortcode: z.string(), courseName: z.string(), teacherId: z.number().int(), type: z.string(), places: z.array(placeRef).optional(), status: z.enum(["available", "booked", "requestable", "requested", "requestAccepted", "requestRejected", "unavailable"]), bookingStartsAt: z.string().nullable(), bookingEndsAt: z.string(), examStartsAt: z.string().nullable(), examEndsAt: z.string().nullable(), bookedCount: z.number().int(), availableCount: z.number().int(), question: z.object({id: z.number().int(), statement: z.string(), options: z.array(z.string())}).nullable(), feedback: z.string().nullable(), isReschedulable: z.boolean(), notes: z.string().nullable(), moduleNumber: z.number().int(), requestReason: z.string().nullable(), requestDetails: z.string().nullable()});

export const getApiExamsResponse = z.object({data: z.array(exam)});

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 exams | Elenca esami
 * 
 * GET /exams
 */
export const getApiExams = async (options?: GetApiExamsOptions) => {
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 (BearerAuth !== undefined) headers.set('authorization', `Bearer ${BearerAuth}`)

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