import {z} from 'zod'

export type TextDoc = {text: string};

export type TextRerankerRequest = {query: string, top_n?: (number | null) | undefined, return_documents?: (boolean | null) | undefined, model: 'jina-reranker-v2-base-multilingual' | 'jina-reranker-v1-tiny-en' | 'jina-reranker-v1-turbo-en' | 'jina-reranker-v1-base-en' | 'jina-colbert-v1-en' | 'jina-colbert-v2', documents: Array<string | TextDoc>};

export type ImageDoc = {image: string};

export type RerankerM0Request = {query: string | ImageDoc, top_n?: (number | null) | undefined, return_documents?: (boolean | null) | undefined, model: 'jina-reranker-m0', documents: Array<string | TextDoc | ImageDoc>};

export type RerankerV3Request = {query: string, top_n?: (number | null) | undefined, return_documents?: (boolean | null) | undefined, model: 'jina-reranker-v3' | 'jina-reranker-v3.5', documents: Array<string | TextDoc>, max_doc_length?: (number | null) | undefined, return_embeddings?: (boolean | null) | undefined};

export type CreateApiV1RerankArgs = {body: TextRerankerRequest | RerankerM0Request | RerankerV3Request};

export type CreateApiV1RerankOptions = {baseUrl?: string | undefined, HTTPBearer?: string | undefined, fetch?: typeof fetch | undefined};

export const baseUsage = z.object({total_tokens: z.number().int()});

export const textDoc = z.object({text: z.string()});

export const imageDoc = z.object({image: z.string()});

export const rerankingResult = z.object({index: z.number().int(), relevance_score: z.number(), document: z.union([z.string(), textDoc, imageDoc]).nullable().optional(), embedding: z.array(z.number()).nullable().optional()});

export const rerankingResponse = z.object({model: z.string(), object: z.string().optional(), usage: baseUsage, results: z.array(rerankingResult)});

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
};

/**
 * Rerank
 * 
 * POST /v1/rerank
 */
export const createApiV1Rerank = async (args: CreateApiV1RerankArgs, options?: CreateApiV1RerankOptions) => {
const {baseUrl = "https://api.jina.ai", fetch: fetchFn = fetch, HTTPBearer} = options ?? {}

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

if (HTTPBearer !== undefined) headers.set('authorization', `Bearer ${HTTPBearer}`)

const url = `${baseUrl.replace(/\/+$/, '')}/v1/rerank${query.size > 0 ? `?${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(rerankingResponse, await res.json())
};