import * as plugins from './smartipc.plugins'
import * as q from 'smartq'

import { Pool } from './smartipc.classes.pool'

export let workerBasePath: string = null

export let setWorkerBasePath = (basePathArg: string) => {
  workerBasePath = basePathArg
  plugins.threads.config.set({
    basepath: {
      node: workerBasePath
    }
  })
}

export class Thread {
  thread
  workerPath: string
  running: boolean = false
  assignedPool: Pool = null
  constructor(filePathArg: string) {
    this.workerPath = filePathArg
  }

  /**
   * sends a message to the spawned process
   * spawns it and keeps running
   */
  send<T>(message: any): Promise<T> {
    let done = q.defer<T>()
    this.checkSpawn()
    this.thread.send(message)
    this.thread.on('message', (message: T) => {
      done.resolve(message)
    })
    this.thread.on('done', (job, message: T) => {
      done.resolve(message)
    })
    this.thread.on('error', err => {
      done.reject(err)
    })
    return done.promise
  }

  /**
   * sends a command once and then kills the child process
   */
  sendOnce<T>(message): Promise<T> {
    let done = q.defer<T>()
    this.send<T>(message).then(message => {
      done.resolve(message)
      this.kill()
    })
    return done.promise
  }

  /**
   * kills the thread
   */
  kill() {
    this.thread.kill()
    this.running = false
  }

  assignToPool(poolArg: Pool) {
    this.assignedPool = poolArg
  }

  private checkSpawn() {
    if (!this.running && !this.assignedPool) {
      this.running = true
      this.thread = plugins.threads.spawn(this.workerPath)
    } else if (!this.running && this.assignedPool) {
      this.running = true
      this.thread = this.assignedPool.run(this.workerPath)
    }
  }
}