import {z} from 'zod'

export type SearchType = 'dense' | 'sparse' | 'hybrid';

export type BodySearchApiKbSearchPost = {collection: string, query_text: string, embedding_model_id?: string | undefined, search_type?: (SearchType | null) | undefined, top_k?: (number | null) | undefined, filters?: ({[key: string]: unknown} | null) | undefined, fusion_config?: ({[key: string]: unknown} | null) | undefined, rerank_model_id?: (string | null) | undefined, rerank_top_k?: (number | null) | undefined, readonly?: (boolean | null) | undefined, nprobes?: (number | null) | undefined, refine_factor?: (number | null) | undefined, fallback_to_sparse?: (boolean | null) | undefined};

export type CreateApiApiKbSearchArgs = {body: BodySearchApiKbSearchPost};

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

export const searchType = z.enum(["dense", "sparse", "hybrid"]);

export const searchResult = z.object({doc_id: z.string(), chunk_id: z.string(), text: z.string(), score: z.number().gte(0).lte(1), parse_hash: z.string(), model_tag: z.string(), created_at: z.string().optional(), metadata: z.record(z.string(), z.unknown()).nullable().optional(), vector_score: z.number().nullable().optional(), fts_score: z.number().nullable().optional(), vector_rank: z.number().int().gte(1).nullable().optional(), fts_rank: z.number().int().gte(1).nullable().optional()});

export const searchPipelineResult = z.object({status: z.string(), search_type: searchType, results: z.array(searchResult).optional(), result_count: z.number().int(), warnings: z.array(z.string()).optional(), message: z.string(), used_rerank: z.boolean().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
 * 
 * POST /api/kb/search
 */
export const createApiApiKbSearch = async (args: CreateApiApiKbSearchArgs, options: CreateApiApiKbSearchOptions) => {
const {baseUrl, fetch: fetchFn = fetch, HTTPBearer} = options ?? {}

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

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

const url = `${baseUrl.replace(/\/+$/, '')}/api/kb/search${query.size > 0 ? `?${query}` : ''}`

const res = await fetchFn(url, {method: "POST", headers, body: new URLSearchParams(Object.entries(args.body).flatMap(([key, value]) => (value == null ? [] : [[key, String(value)]])))})

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

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