import {z} from 'zod'

export type SchemaAttribute = {name?: string | undefined, type?: string | undefined};

export type ConnectorSchema = {name?: string | undefined, attributes?: Array<SchemaAttribute> | undefined};

export type CreateApiApiTransformationsPreviewArgs = {body: {query?: string | undefined, inputSchema?: ConnectorSchema | undefined, outputSchema?: ConnectorSchema | undefined, data?: Array<Record<string, never>> | undefined}};

export type CreateApiApiTransformationsPreviewOptions = {baseUrl: string, ApiKeyAuth?: string | undefined, fetch?: typeof fetch | undefined};

export const schemaAttribute = z.object({name: z.string().optional(), type: z.string().optional()});

export const connectorSchema = z.object({name: z.string().optional(), attributes: z.array(schemaAttribute).optional()});

export const connectorSample = z.object({schema: connectorSchema.optional(), data: z.array(z.object({})).optional()});

export const createApiApiTransformationsPreviewResponse = z.object({error: z.boolean(), code: z.number().int().optional(), result: connectorSample.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
};

/**
 * Generate transformed data preview
 * 
 * POST /_api/transformations/preview
 * 
 * Also accepts auth: BearerAuth
 */
export const createApiApiTransformationsPreview = async (args: CreateApiApiTransformationsPreviewArgs, options: CreateApiApiTransformationsPreviewOptions) => {
const {baseUrl, fetch: fetchFn = fetch, ApiKeyAuth} = options ?? {}

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

if (ApiKeyAuth !== undefined) headers.set("Authorization", ApiKeyAuth)

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