src/worker/worker.js

/**
 * @file Worker
 * @author Alexander Rose <alexander.rose@weirdbyte.de>
 * @private
 */

import { Log, Debug, WorkerRegistry } from '../globals.js'

function Worker (name) {
  var pending = 0
  var postCount = 0
  var onmessageDict = {}
  var onerrorDict = {}

  var blobUrl = window.URL.createObjectURL(WorkerRegistry.get(name))
  var worker = new window.Worker(blobUrl)

  WorkerRegistry.activeWorkerCount += 1

  worker.onmessage = function (event) {
    pending -= 1
    var postId = event.data.__postId

    if (Debug) Log.timeEnd('Worker.postMessage ' + name + ' #' + postId)

    if (onmessageDict[ postId ]) {
      onmessageDict[ postId ].call(worker, event)
    } else {
            // Log.debug( "No onmessage", postId, name );
    }

    delete onmessageDict[ postId ]
    delete onerrorDict[ postId ]
  }

  worker.onerror = function (event) {
    pending -= 1
    if (event.data) {
      var postId = event.data.__postId
      if (onerrorDict[ postId ]) {
        onerrorDict[ postId ].call(worker, event)
      } else {
        Log.error('Worker.onerror', postId, name, event)
      }
      delete onmessageDict[ postId ]
      delete onerrorDict[ postId ]
    } else {
      Log.error('Worker.onerror', name, event)
    }
  }

    // API

  this.name = name

  this.post = function (aMessage, transferList, onmessage, onerror) {
    onmessageDict[ postCount ] = onmessage
    onerrorDict[ postCount ] = onerror

    aMessage = aMessage || {}
    aMessage.__name = name
    aMessage.__postId = postCount
    aMessage.__debug = Debug

    if (Debug) Log.time('Worker.postMessage ' + name + ' #' + postCount)

    try {
      worker.postMessage(aMessage, transferList)
    } catch (error) {
      Log.error('worker.post:', error)
      worker.postMessage(aMessage)
    }

    pending += 1
    postCount += 1

    return this
  }

  this.terminate = function () {
    if (worker) {
      worker.terminate()
      window.URL.revokeObjectURL(blobUrl)
      WorkerRegistry.activeWorkerCount -= 1
    } else {
      Log.log('no worker to terminate')
    }
  }

  Object.defineProperties(this, {
    postCount: {
      get: function () { return postCount }
    },
    pending: {
      get: function () { return pending }
    }
  })
}

Worker.prototype.constructor = Worker

export default Worker