/*
 * Copyright Elasticsearch B.V. and contributors
 * SPDX-License-Identifier: Apache-2.0
 */

// This file was automatically generated by elastic/elastic-client-generator-js
// DO NOT MODIFY IT BY HAND. Instead, modify the source open api file,
// and elastic/elastic-client-generator-js to regenerate this file again.

import {
  Transport,
  TransportRequestMetadata,
  TransportRequestOptions,
  TransportRequestOptionsWithMeta,
  TransportRequestOptionsWithOutMeta,
  TransportResult
} from '@elastic/transport'
import * as T from '../types'

interface That {
  transport: Transport
}

const commonQueryParams = ['error_trace', 'filter_path', 'human', 'pretty']

const acceptedParams: Record<string, { path: string[], body: string[], query: string[] }> = {
  knn_search: {
    path: [
      'index'
    ],
    body: [
      '_source',
      'docvalue_fields',
      'stored_fields',
      'fields',
      'filter',
      'knn'
    ],
    query: [
      'routing'
    ]
  }
}

/**
  * Run a knn search. NOTE: The kNN search API has been replaced by the `knn` option in the search API.
  */
export default async function KnnSearchApi<TDocument = unknown> (this: That, params: T.KnnSearchRequest, options?: TransportRequestOptionsWithOutMeta): Promise<T.KnnSearchResponse<TDocument>>
export default async function KnnSearchApi<TDocument = unknown> (this: That, params: T.KnnSearchRequest, options?: TransportRequestOptionsWithMeta): Promise<TransportResult<T.KnnSearchResponse<TDocument>, unknown>>
export default async function KnnSearchApi<TDocument = unknown> (this: That, params: T.KnnSearchRequest, options?: TransportRequestOptions): Promise<T.KnnSearchResponse<TDocument>>
export default async function KnnSearchApi<TDocument = unknown> (this: That, params: T.KnnSearchRequest, options?: TransportRequestOptions): Promise<any> {
  const {
    path: acceptedPath,
    body: acceptedBody,
    query: acceptedQuery
  } = acceptedParams.knn_search

  const userQuery = params?.querystring
  const querystring: Record<string, any> = userQuery != null ? { ...userQuery } : {}

  let body: Record<string, any> | string | undefined
  const userBody = params?.body
  if (userBody != null) {
    if (typeof userBody === 'string') {
      body = userBody
    } else {
      body = { ...userBody }
    }
  }

  for (const key in params) {
    if (acceptedBody.includes(key)) {
      body = body ?? {}
      // @ts-expect-error
      body[key] = params[key]
    } else if (acceptedPath.includes(key)) {
      continue
    } else if (key !== 'body' && key !== 'querystring') {
      if (acceptedQuery.includes(key) || commonQueryParams.includes(key)) {
        // @ts-expect-error
        querystring[key] = params[key]
      } else {
        body = body ?? {}
        // @ts-expect-error
        body[key] = params[key]
      }
    }
  }

  const method = body != null ? 'POST' : 'GET'
  const path = `/${encodeURIComponent(params.index.toString())}/_knn_search`
  const meta: TransportRequestMetadata = {
    name: 'knn_search',
    pathParts: {
      index: params.index
    },
    acceptedParams: {
      path: ['index'],
      body: ['_source', 'docvalue_fields', 'stored_fields', 'fields', 'filter', 'knn'],
      query: ['routing']
    }
  }
  return await this.transport.request({ path, method, querystring, body, meta }, options)
}
