import {
  QueryClient,
  QueryKey,
  useQuery,
  useQueryClient,
  UseQueryOptions,
} from '@tanstack/react-query'
import md5 from 'blueimp-md5'
import { post } from 'lib/common/fetch'
import { API_URL } from 'lib/constants'
import { useCallback } from 'react'
import { sqlKeys } from './keys'
import { noop } from 'lodash'

export type Error = { code: number; message: string; requestId: string }

export type ExecuteSqlVariables = {
  projectRef?: string
  connectionString?: string
  sql: string
  queryKey?: QueryKey
  handleError?: (error: { code: number; message: string; requestId: string }) => any
}

export async function executeSql(
  {
    projectRef,
    connectionString,
    sql,
    queryKey,
    handleError,
  }: Pick<
    ExecuteSqlVariables,
    'projectRef' | 'connectionString' | 'sql' | 'queryKey' | 'handleError'
  >,
  signal?: AbortSignal
) {
  if (!projectRef) {
    throw new Error('projectRef is required')
  }

  let headers = new Headers()

  if (connectionString) {
    headers.set('x-connection-encrypted', connectionString)
  }

  const response = await post(
    `${API_URL}/pg-meta/${projectRef}/query${
      queryKey ? `?key=${queryKey.filter((seg) => typeof seg === 'string').join('-')}` : ''
    }`,
    { query: sql },
    { headers: Object.fromEntries(headers), signal }
  )

  if (response.error) {
    if (handleError !== undefined) {
      return handleError(response.error)
    } else {
      throw response.error
    }
  }

  return { result: response }
}

export type ExecuteSqlData = Awaited<ReturnType<typeof executeSql>>
export type ExecuteSqlError = unknown

export const useExecuteSqlQuery = <TData = ExecuteSqlData>(
  { projectRef, connectionString, sql, queryKey, handleError }: ExecuteSqlVariables,
  { enabled = true, ...options }: UseQueryOptions<ExecuteSqlData, ExecuteSqlError, TData> = {}
) =>
  useQuery<ExecuteSqlData, ExecuteSqlError, TData>(
    sqlKeys.query(projectRef, queryKey ?? [md5(sql)]),
    ({ signal }) =>
      executeSql({ projectRef, connectionString, sql, queryKey, handleError }, signal),
    { enabled: enabled && typeof projectRef !== 'undefined', ...options }
  )

export const prefetchExecuteSql = (
  client: QueryClient,
  { projectRef, connectionString, sql, queryKey, handleError }: ExecuteSqlVariables
) => {
  return client.prefetchQuery(sqlKeys.query(projectRef, queryKey ?? [md5(sql)]), ({ signal }) =>
    executeSql({ projectRef, connectionString, sql, queryKey, handleError }, signal)
  )
}

/**
 * useExecuteSqlPrefetch is used for prefetching a SQL query. For example, starting a query loading before a page is navigated to.
 *
 * @example
 * const prefetch = useExecuteSqlPrefetch()
 *
 * return (
 *   <Link onMouseEnter={() => prefetch({ ...args })}>
 *     Start loading on hover
 *   </Link>
 * )
 */
export const useExecuteSqlPrefetch = () => {
  const client = useQueryClient()

  return useCallback(
    ({ projectRef, connectionString, sql, queryKey, handleError }: ExecuteSqlVariables) => {
      if (projectRef) {
        return prefetchExecuteSql(client, {
          projectRef,
          connectionString,
          sql,
          queryKey,
          handleError,
        })
      }

      return Promise.resolve()
    },
    [client]
  )
}