const env = require('config.js') // 配置文件，在这文件里配置你的OSS keyId和KeySecret,timeout:87600;

const base64 = require('base64.js')// Base64,hmac,sha1,crypto相关算法
require('hmac.js')
require('sha1.js')
const Crypto = require('crypto.js')

const getSuffix = function (filename) {
	const pos = filename.lastIndexOf('.')
	let suffix = ''
	if (pos !== -1) {
		suffix = filename.substring(pos)
	}
	return suffix
}

/*
 *上传文件到阿里云oss
 *@param - filePath :本地资源路径
 *@param - dir:表示要传到哪个目录下
 *@param - successc:成功回调
 *@param - failc:失败回调
 */

const uploadFile = async function (filePath, dir, successc, failc) {
	const data = await getApp().doPost({
		url: 'display/doGenUploadUrl.json',
		params: dir
	})
	console.log(data)
	// 图片名字 可以自行定义，     这里是采用当前的时间戳 + 150内的随机数来给图片命名的
	const aliyunFileKey = dir + new Date().getTime() + Math.floor(Math.random() * 150) + getSuffix(filePath)

	const aliyunServerURL = env.uploadImageUrl// OSS地址，需要https
	// const accessid = env.OSSAccessKeyId
	// const policyBase64 = getPolicyBase64()
	// const signature = getSignature(policyBase64)// 获取签名

	wx.uploadFile({
		url: aliyunServerURL, // 开发者服务器 url
		filePath: filePath, // 要上传文件资源的路径
		name: 'file', // 必须填file
		formData: {
			'key': aliyunFileKey,
			'policy': data.policy,
			'OSSAccessKeyId': data.accessKeyId,
			'signature': data.signature,
			'success_action_status': '200'
		},
		success: function (res) {
			if (res.statusCode !== 200) {
				failc(new Error('上传错误:' + JSON.stringify(res)))
				return
			}
			successc(aliyunServerURL + '/' + aliyunFileKey)
		},
		fail: function (err) {
			err.wxaddinfo = aliyunServerURL
			failc(err)
		}
	})
}

const getPolicyBase64 = function () {
	const date = new Date()
	date.setHours(date.getHours() + env.timeout)
	const srcT = date.toISOString()

	const policyText = {
		'expiration': srcT, // 设置该Policy的失效时间，超过这个失效时间之后，就没有办法通过这个policy上传文件了
		'conditions': [
			['content-length-range', 0, 100000 * 1024 * 1024] // 设置上传文件的大小限制,500mb
		]
	}

	const policyBase64 = base64.encode(JSON.stringify(policyText))
	return policyBase64
}

const getSignature = function (policyBase64) {
	const accesskey = env.AccessKeySecret

	const bytes = Crypto.HMAC(Crypto.SHA1, policyBase64, accesskey, {
		asBytes: true
	})
	const signature = Crypto.util.bytesToBase64(bytes)

	return signature
}

module.exports = uploadFile