import {z} from 'zod'

export type AssistImage = {data_base64: string, media_type: 'image/png' | 'image/jpeg', width_px: number, height_px: number};

export type AssistTransform = {a: number, b: number, c: number, d: number, e: number, f: number};

export type RescueCandidate = {far_point: Array<unknown>, angle_deg: number};

export type RescueContext = {stop_point: Array<unknown>, heading_deg: number, goal_point: Array<unknown> | null, candidates: Array<RescueCandidate>, bridge_point: Array<unknown> | null};

export type CompleteContext = {placed_vertices: Array<Array<unknown>>, tool: 'polyline' | 'polygon'};

export type AutocompleteAssistRequest = {kind: 'rescue' | 'complete', image: AssistImage, transform: AssistTransform, rescue?: (RescueContext | null) | undefined, complete?: (CompleteContext | null) | undefined};

export type CreateApiApiV1PagesPageIdAutocompleteAssistArgs = {page_id: string, body: AutocompleteAssistRequest};

export type CreateApiApiV1PagesPageIdAutocompleteAssistOptions = {baseUrl: string, fetch?: typeof fetch | undefined};

export const rescueAssistResult = z.object({kind: z.literal("rescue").optional(), choice: z.union([z.number().int(), z.enum(["bridge", "none"])])});

export const completeAssistResult = z.object({kind: z.literal("complete").optional(), vertices_pdf: z.array(z.array(z.unknown())), confidence: z.enum(["high", "low"])});

export const autocompleteAssistResponse = z.object({assist: z.union([rescueAssistResult, completeAssistResult]).nullable().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
};

/**
 * Autocomplete Assist
 * 
 * POST /api/v1/pages/{page_id}/autocomplete-assist
 */
export const createApiApiV1PagesPageIdAutocompleteAssist = async (args: CreateApiApiV1PagesPageIdAutocompleteAssistArgs, options: CreateApiApiV1PagesPageIdAutocompleteAssistOptions) => {
const {baseUrl, fetch: fetchFn = fetch} = options ?? {}

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

const url = `${baseUrl.replace(/\/+$/, '')}/api/v1/pages/${encodeURIComponent(String(args.page_id))}/autocomplete-assist${query.size > 0 ? `?${query}` : ''}`

const res = await fetchFn(url, {method: "POST", headers, body: JSON.stringify(args.body)})

if (!res.ok) throw new Error(`Request failed with status ${res.status}`, {cause: {status: res.status, body: await res.text()}})

return validateResponse(autocompleteAssistResponse, await res.json())
};