import {z} from 'zod'

export type SearchRequest = {query: string, kb_ids: Array<string>, rerank?: boolean | undefined, limit?: number | undefined, prefer_draft?: boolean | undefined, version_overrides?: ({[key: string]: string} | null) | undefined, alpha?: number | undefined};

export type CreateApiV1KnowledgeBaseSearchArgs = {body: SearchRequest};

export type CreateApiV1KnowledgeBaseSearchOptions = {baseUrl: string, APIKeyHeader?: string | undefined, fetch?: typeof fetch | undefined};

export const textPosition = z.object({type: z.literal("text").optional(), start_char: z.number().int().gte(0), end_char: z.number().int().gte(0)});

export const searchResult = z.object({chunk_id: z.string(), kb_id: z.string(), document_id: z.string(), version_id: z.string().optional(), document_title: z.string(), source_type: z.string(), content: z.string(), score: z.number(), chunk_index: z.number().int(), position: textPosition.nullable().optional(), sensitivity: z.string().nullable().optional(), sensitivity_level: z.number().int().nullable().optional(), pii_status: z.string().optional(), pii_sensitivity: z.string().optional(), pii_coverage_status: z.string().optional()});

export const searchResultGroup = z.object({embedding_model: z.string(), embedding_dimensions: z.number().int(), kb_ids: z.array(z.string()), results: z.array(searchResult)});

export const searchAnswerability = z.object({label: z.enum(["answerable", "low_confidence", "not_answerable", "unknown"]), reason_code: z.enum(["no_results", "below_low_threshold", "weak_band", "above_high_threshold", "not_actionable_basis", "verdict_failed"]), raw_top_score: z.number().nullable().optional(), score_basis: z.enum(["raw_dotproduct", "minmax_norm", "cohere_rerank", "grouped"])});

export const searchResponse = z.object({results: z.array(searchResult), total_results: z.number().int(), grouped_results: z.array(searchResultGroup).nullable().optional(), ranking_mode: z.enum(["global_score", "reranked", "grouped_unranked"]), answerability: searchAnswerability.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
};

/**
 * Semantic search across knowledge bases
 * 
 * POST /v1/knowledge-base/search
 */
export const createApiV1KnowledgeBaseSearch = async (args: CreateApiV1KnowledgeBaseSearchArgs, options: CreateApiV1KnowledgeBaseSearchOptions) => {
const {baseUrl, fetch: fetchFn = fetch, APIKeyHeader} = options ?? {}

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

if (APIKeyHeader !== undefined) headers.set("x-api-key", APIKeyHeader)

const url = `${baseUrl.replace(/\/+$/, '')}/v1/knowledge-base/search${query.size > 0 ? `?${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(searchResponse, await res.json())
};