polly

import fs from 'node:fs'
import { Ok, Error as GError, toList } from './gleam.mjs'
import  * as $polly from './polly.mjs'

export function readdir(filepath) {
  return gleamResult(() => toList(fs.readdirSync(filepath)))
}

export function lstat(filepath) {
  return gleamResult(() => {
    const stat = fs.lstatSync(filepath)
    const mode = stat.mode
    const type = 
        ((mode & fs.constants.S_IFMT) === fs.constants.S_IFLNK) ? new $polly.Symlink()
      : ((mode & fs.constants.S_IFMT) === fs.constants.S_IFDIR) ? new $polly.Directory()
      : ((mode & fs.constants.S_IFMT) === fs.constants.S_IFREG) ? new $polly.Regular()
      : ((mode & fs.constants.S_IFMT) === fs.constants.S_IFCHR) ? new $polly.Device()
      : new $polly.Other()

    const read = (mode & (fs.constants.S_IRUSR | fs.constants.S_IRGRP | fs.constants.S_IROTH))
    const write = (mode & (fs.constants.S_IWUSR | fs.constants.S_IWGRP | fs.constants.S_IWOTH))

    const access = read && write ? new $polly.ReadWrite()
      : read ? new $polly.Read()
      : write ? new $polly.Write()
      : new $polly.None()
    
    return new $polly.Stat(
      stat.size,
      type,
      access,
      Math.trunc(stat.atimeMs / 1000),
      Math.trunc(stat.mtimeMs / 1000),
      Math.trunc(stat.ctimeMs / 1000),
      mode,
      stat.nlink,
      stat.dev,
      stat.rdev,
      stat.ino,
      stat.uid,
      stat.gid
    )
  })
}

export function repeatedly(timeout, state, callback) {
  let timerId = setTimeout(step, timeout)
  return stop
  
  function step() {
    state = callback(state)
    timerId = setTimeout(step, timeout)
  }

  function stop() {
    clearTimeout(timerId)
  }
}

function gleamResult(f) {
  try {
    return new Ok(f())
  } catch(e) {
    switch (e.code) {
      case 'EACCES': return new GError(new $polly.Eacces())
      case 'ENOENT': return new GError(new $polly.Enoent())
      case 'ENODIR': return new GError(new $polly.Enotdir())
      // map_error will fix her!
      default: return new GError(e.code)
    }
  }
}