candle.js

"use strict";

var timers = require('timers');
var util = require('util');
var debug = require('debug')('candle');

var Timeout = function () {
};

var TimeoutError = function () {
  Error.captureStackTrace(this, TimeoutError);
};
util.inherits(TimeoutError, Error);
TimeoutError.prototype.name = 'TimeoutError';

var Candle = function () {
  this.callbacks = Object.create(null);
  this.id = 0;
  this.timeoutResolver = null;
};
Candle.prototype.add = function (callback) {
  var id = ++this.id;
  debug('add(...), assigned id = ' + id);
  this.callbacks[id] = [callback, null];
  return id;
};
Candle.prototype.resolve = function (id, err, result) {
  debug('resolve(' + id + ', ...)');
  var l = arguments.length, callback = this.callbacks[id], i, args;
  if (callback && callback[0]) {
    this.remove(id);
    if (l === 1) {
      callback[0]();
    } else if (l === 2) {
      callback[0](err);
    } else if (l === 3) {
      callback[0](err, result);
    } else {
      args = new Array(l - 1);
      for (i = 1; i < l; i++) {
        args[i - 1] = arguments[i];
      }
      callback[0].apply(this, args);
    }
  }
};
Candle.prototype.remove = function (id) {
  debug('remove(' + id + ')');
  this.clearTimeout(id);
  delete this.callbacks[id];
};
Candle.prototype.setTimeout = function (id, timeout) {
  debug('setTimeout(' + id + ')');
  if (!this.callbacks[id]) {
    return;
  }
  this.clearTimeout(id);
  this.callbacks[id][1] = timers.setTimeout(this.getTimeout(id), timeout);
};
Candle.prototype.clearTimeout = function (id) {
  debug('clearTimeout(' + id + ')');
  if (this.callbacks[id] && this.callbacks[id][1]) {
    timers.clearTimeout(this.callbacks[id][1]);
  }
  this.callbacks[id][1] = null;
};
Candle.prototype.getTimeout = function (id) {
  var self = this;
  return function () {
    return self.onTimeout(id);
  };
};
Candle.prototype.onTimeout = function (id) {
  debug('onTimeout(' + id + ')');
  if (typeof this.timeoutResolver === 'function') {
    this.timeoutResolver(id);
  } else {
    this.resolve(id, new Timeout());
  }
};
Candle.prototype.setTimeoutResolver = function (callback) {
  this.timeoutResolver = callback;
};
var create = function () {
  return new Candle();
};

module.exports = Candle;
module.exports.create = create;
module.exports.Timeout = Timeout;
module.exports.TimeoutError = TimeoutError;