import envPaths from 'env-paths'
import { sync as mkdir } from 'make-dir'
import { dirname } from 'path'
import { createWriteStream, createReadStream } from 'fs'
import crypto from 'crypto'
import debounce from 'debounce-fn'

function write (opts = {}) {
  const path = opts.path ? opts.path : `${envPaths(opts.name || 'history', { suffix: null }).log}/${opts.name || process.pid}.log`
  mkdir(dirname(path)) // makes recursively for any missing parent directories

  const create = (path, clear) => {
    const stream = createWriteStream(path, { flags: `${clear ? 'w' : 'a'}` })
    // todo make sure stream was made
    stream.on('close', (data) => {
      console.log('the stream to history file was closed')
    })
    return stream
  }

  let output = create(path, opts.clear)

  const _write = (obj) => {
    if (output.writable) {
      const tStamp = new Date()
      const keys = {
        _id: crypto.randomBytes(8).toString('hex'),
        time: tStamp.getTime(),
        datetime: tStamp.toString(),
        utc: tStamp.toISOString()
      }
      if (typeof obj === 'string') obj = { msg: obj }
      obj = Object.assign(keys, opts.keys, obj)
      console.log('writing', obj)
      output.write(JSON.stringify(obj) + '\n', function () {
        debounce(output.destroy.bind(output), { wait: opts.close || 5000 })()
      })
    } else {
      console.log('there is no stream, recreating')
      output = create(path)
      _write(obj)
    }
  }
  return _write
}

function view (handler, opts) {

}

export default write
export { write, view }