import {z} from 'zod'

export type EntityType = 'person' | 'organisation' | 'location' | 'substance' | 'disease' | 'product' | 'regulation';

export type Base64String = string;

export type GetApiEntitiesArgs = {name?: string | undefined, type?: EntityType | undefined, size?: number | undefined, 'from-cursor'?: Base64String | undefined};

export type GetApiEntitiesOptions = {baseUrl?: string | undefined, OAuth2?: string | undefined, fetch?: typeof fetch | undefined};

export const resourceId = z.string();

export const entityType = z.enum(["person", "organisation", "location", "substance", "disease", "product", "regulation"]);

export const entity = z.object({id: resourceId, type: entityType, name: z.string()});

export const base64String = z.string();

export const entitiesResponse = z.object({entities: z.array(entity), "next-cursor": base64String.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
};

/**
 * Search A.I. trained entities by type and name
 * 
 * GET /entities
 */
export const getApiEntities = async (args: GetApiEntitiesArgs, options?: GetApiEntitiesOptions) => {
const {baseUrl = "https://api.signal-ai.com", fetch: fetchFn = fetch, OAuth2} = options ?? {}

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

if (args.name != null) query.append("name", String(args.name))
if (args.type != null) query.append("type", String(args.type))
if (args.size != null) query.append("size", String(args.size))
if (args['from-cursor'] != null) query.append("from-cursor", String(args['from-cursor']))
if (OAuth2 !== undefined) headers.set('authorization', `Bearer ${OAuth2}`)

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