#!/usr/bin/env node

const path = require('path')
const cluster = require('cluster')

require('dotenv').config({ path: path.resolve(__dirname, '../.env') })

const config = require('../src/config')
const service = require('../index.js')
const logger = require('../src/util/logger')

let shuttingDown = false

const shutDown = signal => {
  if (!cluster.isMaster) {
    return
  }

  shuttingDown = true

  logger.log('Emote server is shutting down…')

  let exitCode = 0

  const promises = []
  const workerIds = Object.keys(cluster.workers)

  for (const id of workerIds) {
    const worker = cluster.workers[id]

    promises.push(new Promise(resolve => {
      let resolved = false

      worker.once('exit', () => {
        if (resolved) {
          return
        }

        resolved = true

        resolve()
      })

      setTimeout(() => {
        if (resolved) {
          return
        }

        resolved = true

        logger.log('Could not close worker in time, killing it.', 'error')

        worker.kill(signal)

        exitCode = 1

        resolve()
      }, 4000)
    }))

    worker.send('shutdown')
    worker.disconnect()
  }

  Promise.all(promises).then(() => {
    process.exit(exitCode)
  })
}

;(async () => {
  if (cluster.isMaster) {
    logger.log('Emote server is starting…')

    const numberOfWorkers = config.numberOfWorkers > 1
      ? config.numberOfWorkers
      : 1

    for (let i = 0; i < numberOfWorkers; i++) {
      cluster.fork()
    }

    cluster.on('exit', worker => {
      if (!shuttingDown) {
        cluster.fork()
      }
    })

    logger.log('Emote server has started.')
  } else {
    await service.start(config.port)

    process.on('message', async message => {
      if (message === 'shutdown') {
        await service.close()
      }
    })
  }
})()

process.on('SIGTERM', () => {
  shutDown('SIGTERM')
})

process.on('SIGINT', () => {
  shutDown('SIGINT')
})