/**
 *  这是一个数字步进器的工具
 **/
layui.define(['jquery'], function (exports) {
    var $ = layui.jquery;

    var angelCountUp = function (argums, startNum, endNum) {
        /**
         *  用法1.当argums是JSON对象
         *  方法的startNum,endNum这两个参数无效
         *  eg: var Count = new CountUp({target:$(".box")});
         *          Count.start();
         *   argums{
                 target ： 目标元素
                 startVal ： 你想要开始的值，默认值为0
                 endVal ： 你想要到达的值，默认值为元素的值
                 decimals ： 小数位数，默认值为0
                 duration ： 动画持续时间为秒，默认值为2
                 options ：选项的可选对象
         *  }
         *  用法2.当argums为字符串或者为jq元素（推荐是JQ元素哦,也可以是dom元素）
         *  eg: var box = new CountUp(".box");
         *      box.start();//开始执行
         *  为字符串一定是个元素的JQ选择器
         *  startNum：默认值0
         *  endNum：默认值为元素的值
         */
        if ((typeof argums == "string") || (argums instanceof $) || (argums instanceof HTMLElement)) {
            var temp = argums;
            startNum = startNum || 0;
            endNum = endNum || $($(argums.target)[0]).text();
            argums = {
                target: $(argums)[0],
                startVal: startNum,
                endVal: endNum,
            }
        }
        argums.startVal = argums.startVal || 0;
        argums.target = $(argums.target)[0];
        argums.endVal = argums.endVal || $($(argums.target)[0]).text();
        /*var {
            target,
            startVal,
            endVal,
            decimals,
            duration,
            options
        } = argums;// 这里是ES6语法*/
        var target = argums.target,
           startVal = argums.startVal,
           endVal = argums.endVal,
           decimals = argums.decimals,
           duration = argums.duration,
           options = argums.options;
        var self = this;
        self.version = function () {
            return "1.9.2"
        };
        self.options = {
            useEasing: true,
            useGrouping: true,
            separator: ",",
            decimal: ".",
            easingFn: easeOutExpo,
            formattingFn: formatNumber,
            prefix: "",
            suffix: "",
            numerals: []
        };

        if (options && typeof options === "object") {
            for (var key in self.options) {
                if (options.hasOwnProperty(key) && options[key] !== null) {
                    self.options[key] = options[key]
                }
            }
        }
        if (self.options.separator === "") {
            self.options.useGrouping = false
        } else {
            self.options.separator = "" + self.options.separator
        }
        var lastTime = 0;
        var vendors = ["webkit", "moz", "ms", "o"];
        for (var x = 0; x < vendors.length && !window.requestAnimationFrame; ++x) {
            window.requestAnimationFrame = window[vendors[x] + "RequestAnimationFrame"];
            window.cancelAnimationFrame = window[vendors[x] + "CancelAnimationFrame"] || window[vendors[x] +
            "CancelRequestAnimationFrame"]
        }
        if (!window.requestAnimationFrame) {
            window.requestAnimationFrame = function (callback, element) {
                var currTime = new Date().getTime();
                var timeToCall = Math.max(0, 16 - (currTime - lastTime));
                var id = window.setTimeout(function () {
                    callback(currTime + timeToCall)
                }, timeToCall);
                lastTime = currTime + timeToCall;
                return id
            }
        }
        if (!window.cancelAnimationFrame) {
            window.cancelAnimationFrame = function (id) {
                clearTimeout(id)
            }
        }

        function formatNumber(num) {
            num = num.toFixed(self.decimals);
            num += "";
            var x, x1, x2, x3, i, l;
            x = num.split(".");
            x1 = x[0];
            x2 = x.length > 1 ? self.options.decimal + x[1] : "";
            if (self.options.useGrouping) {
                x3 = "";
                for (i = 0, l = x1.length; i < l; ++i) {
                    if (i !== 0 && ((i % 3) === 0)) {
                        x3 = self.options.separator + x3
                    }
                    x3 = x1[l - i - 1] + x3
                }
                x1 = x3
            }
            if (self.options.numerals.length) {
                x1 = x1.replace(/[0-9]/g, function (w) {
                    return self.options.numerals[+w]
                });
                x2 = x2.replace(/[0-9]/g, function (w) {
                    return self.options.numerals[+w]
                })
            }
            return self.options.prefix + x1 + x2 + self.options.suffix
        }

        function easeOutExpo(t, b, c, d) {
            return c * (-Math.pow(2, -10 * t / d) + 1) * 1024 / 1023 + b
        }

        function ensureNumber(n) {
            return (typeof n === "number" && !isNaN(n))
        }

        self.initialize = function () {
            if (self.initialized) {
                return true
            }
            self.error = "";
            // self.d = (typeof target === "string") ? document.getElementById(target) : target;
            self.d = target;
            if (!self.d) {
                self.error = "[CountUp] target is null or undefined";
                return false
            }
            self.startVal = Number(startVal);
            self.endVal = Number(endVal);
            if (ensureNumber(self.startVal) && ensureNumber(self.endVal)) {
                self.decimals = Math.max(0, decimals || 0);
                self.dec = Math.pow(10, self.decimals);
                self.duration = Number(duration) * 1000 || 2000;
                self.countDown = (self.startVal > self.endVal);
                self.frameVal = self.startVal;
                self.initialized = true;
                return true
            } else {
                self.error = "[CountUp] startVal (" + startVal + ") or endVal (" + endVal + ") is not a number";
                return false
            }
        };
        self.printValue = function (value) {
            var result = self.options.formattingFn(value);
            if (self.d.tagName === "INPUT") {
                this.d.value = result
            } else {
                if (self.d.tagName === "text" || self.d.tagName === "tspan") {
                    this.d.textContent = result
                } else {
                    this.d.innerHTML = result
                }
            }
        };
        self.count = function (timestamp) {
            if (!self.startTime) {
                self.startTime = timestamp
            }
            self.timestamp = timestamp;
            var progress = timestamp - self.startTime;
            self.remaining = self.duration - progress;
            if (self.options.useEasing) {
                if (self.countDown) {
                    self.frameVal = self.startVal - self.options.easingFn(progress, 0, self.startVal - self.endVal,
                        self.duration)
                } else {
                    self.frameVal = self.options.easingFn(progress, self.startVal, self.endVal - self.startVal,
                        self.duration)
                }
            } else {
                if (self.countDown) {
                    self.frameVal = self.startVal - ((self.startVal - self.endVal) * (progress / self.duration))
                } else {
                    self.frameVal = self.startVal + (self.endVal - self.startVal) * (progress / self.duration)
                }
            }
            if (self.countDown) {
                self.frameVal = (self.frameVal < self.endVal) ? self.endVal : self.frameVal
            } else {
                self.frameVal = (self.frameVal > self.endVal) ? self.endVal : self.frameVal
            }
            self.frameVal = Math.round(self.frameVal * self.dec) / self.dec;
            self.printValue(self.frameVal);
            if (progress < self.duration) {
                self.rAF = requestAnimationFrame(self.count)
            } else {
                if (self.callback) {
                    self.callback()
                }
            }
        };
        self.start = function (callback) {
            if (!self.initialize()) {
                return
            }
            self.callback = callback;
            self.rAF = requestAnimationFrame(self.count)
        };
        self.pauseResume = function () {
            if (!self.paused) {
                self.paused = true;
                cancelAnimationFrame(self.rAF)
            } else {
                self.paused = false;
                delete self.startTime;
                self.duration = self.remaining;
                self.startVal = self.frameVal;
                requestAnimationFrame(self.count)
            }
        };
        self.reset = function () {
            self.paused = false;
            delete self.startTime;
            self.initialized = false;
            if (self.initialize()) {
                cancelAnimationFrame(self.rAF);
                self.printValue(self.startVal)
            }
        };
        self.update = function (newEndVal) {
            if (!self.initialize()) {
                return
            }
            newEndVal = Number(newEndVal);
            if (!ensureNumber(newEndVal)) {
                self.error = "[CountUp] update() - new endVal is not a number: " + newEndVal;
                return
            }
            self.error = "";
            if (newEndVal === self.frameVal) {
                return
            }
            cancelAnimationFrame(self.rAF);
            self.paused = false;
            delete self.startTime;
            self.startVal = self.frameVal;
            self.endVal = newEndVal;
            self.countDown = (self.startVal > self.endVal);
            self.rAF = requestAnimationFrame(self.count)
        };
        if (self.initialize()) {
            self.printValue(self.startVal)
        }
    };

    exports('angelCountUp', angelCountUp);
});

