/**

 * Created by wangyy on 2016/12/26.

 */
'use strict';
class NumberAnimate {



 constructor(opt) {

  let def = {

   from: 50, //开始时的数字

   speed: 2000, // 总时间

   refreshTime: 100, // 刷新一次的时间

   decimals: 2, // 小数点后的位数

   onUpdate: function() {}, // 更新时回调函数

   onComplete: function() {} // 完成时回调函数

  }

  this.tempValue = 0; //累加变量值

  this.opt = Object.assign(def, opt); //assign传入配置参数

  this.loopCount = 0; //循环次数计数

  this.loops = Math.ceil(this.opt.speed / this.opt.refreshTime); //数字累加次数

  this.increment = (this.opt.from / this.loops); //每次累加的值

  this.interval = null; //计时器对象

  this.init();

 }

 init() {

  this.interval = setInterval(() => {
   this.updateTimer()
  }, this.opt.refreshTime);

 }



 updateTimer() {



  this.loopCount++;

  this.tempValue = this.formatFloat(this.tempValue, this.increment).toFixed(this.opt.decimals);

  if (this.loopCount >= this.loops) {

   clearInterval(this.interval);

   this.tempValue = this.opt.from;

   this.opt.onComplete();

  }

  this.opt.onUpdate();

 }

 //解决0.1+0.2不等于0.3的小数累加精度问题

 formatFloat(num1, num2) {

  let baseNum, baseNum1, baseNum2;

  try {

   baseNum1 = num1.toString().split(".")[1].length;

  } catch (e) {

   baseNum1 = 0;

  }

  try {

   baseNum2 = num2.toString().split(".")[1].length;

  } catch (e) {

   baseNum2 = 0;

  }

  baseNum = Math.pow(10, Math.max(baseNum1, baseNum2));

  return (num1 * baseNum + num2 * baseNum) / baseNum;

 };
}
export default NumberAnimate;