//防抖 延迟执行
export function debounce(fn, delay = 500) {
	let timer
	return function() {
		let args = arguments
		if (timer) clearTimeout(timer)
		timer = setTimeout(() => {
			timer = null
			fn.apply(this, args)
		}, delay)
	}
}
//节流 首次执行
export function throttle(fn, delay = 1000) {
	let last = 0
	return function() {
		let now = new Date()
		if (now - last > delay) {
			fn.apply(this, arguments)
			last = now
		}
	}
}
//提示
const toast = (msg, mask = true, icon = 'none', duration = 1500) => {
	uni.showToast({
		title: String(msg),
		icon: icon,
		mask: mask,
		duration: duration,
	})
}
//加载
const loading = (msg = '努力加载中', mask = true) => {
	uni.showLoading({
		title: String(msg),
		mask: mask,
	})
}
//json参数转url参数
const jsonToUrl = (path, param) => {
	let url = path
	let arr = []
	if (param) arr = Object.keys(param)
	if (arr.length && arr.length != 0) {
		let str = arr.map(key => `${key}=${decodeURIComponent(param[key])}`).join('&')
		url = `${path}${path ? '?' : ''}${str}`
	}
	return url
}
//url参数转json参数
const urlToJson = (url) => {
	let path = url
	let param = {}
	if (url.indexOf('?') != -1) {
		path = url.substr(0, url.indexOf('?'))
		let arr = url.split("?")[1].split("&")  
		arr.forEach(i=>{
			if (i.split("=")[1] && i.split("=")[1] != 'undefined') param[i.split("=")[0]] = i.split("=")[1]
		})
	} 
	return { path, param }
}
//url获取指定参数
const getQuery = (key) => {
	 let query = window.location.search.substring(1);
	 let vars = query.split("&");
	 for (let i=0;i<vars.length;i++) {
		let pair = vars[i].split("=");
		if (pair[0] == key) {return pair[1];}
	 }
	 return(false)
}
//加法   
Number.prototype.add = function(arg) {   
  return (Math.round(this * 100) + Math.round(arg * 100)) / 100
}     
//减法   
Number.prototype.sub = function(arg) {
	arg = -arg
	return (Math.round(this * 100) + Math.round(arg * 100)) / 100
}   
//乘法   
Number.prototype.mul = function(arg) {   
	return (Math.round(this * 100) * Math.round(arg * 100)) / 10000
}  
//除法   
Number.prototype.div = function(arg) {   
	let d1, d2, n1, n2
	n1 = Number(this.toString().replace(".", ""))
	n2 = Number(arg.toString().replace(".", ""))
	try {d1 = this.toString().split(".")[1].length;} catch (e) {d1 = 0;}
	try {d2 = arg.toString().split(".")[1].length;} catch (e) {d2 = 0;}
	return toFixed((n1 / n2) * Math.pow(10, d2 - d1), 2)
} 
//四舍五入保留小数
function toFixed(arg, n) {
	if (n == 0) {
		return Math.round(arg)
	}
	try {
		var d, carryD, i, 
		ds = arg.toString().split('.'),
		len = ds[1].length,
		b0 = '', k = 0
		if (len > n) {
			while(k < n && ds[1].substring(0, ++k) == '0') {
				b0 += '0'
			}
			d = Number(ds[1].substring(0, n))
			carryD = Math.round(Number('0.' + ds[1].substring(n, len)))
			len = (d + carryD).toString().length
			if (len > n) {
				return Number(ds[0]) + 1
			} else if (len == n) {
				return Number(ds[0] + '.' + (d + carryD))
			}
			return Number(ds[0] + '.' + b0 + (d + carryD))
		}
	} catch (e) {}
	return arg
}
//输出
export default {
	toast,
	loading,
	jsonToUrl,
	urlToJson,
	getQuery,
}