/*
* @Author: Echonessy
* @Date:   2020-10-15
* @Function : 小程序二維碼生成與獲取
*/
const request = require('request');

const appid = '你的小程序appid';
const appSecret = '你的小程序appSecret ';

//  String buffer 轉(zhuǎn)base64
const toBase64 = (body) => {
    let base64Img = new Buffer.from(body, 'binary').toString('base64');
    let decodeImg = new Buffer.from(base64Img, 'base64');
    let binaryBuffer = new Buffer.from(decodeImg, 'binary');
    let src = 'data: image/png;base64,' + binaryBuffer.toString('base64');
    return src
}

// 獲取token
const getAccessToken = (appid,appSecret) => {
    return new Promise((resolve, reject) => {
        let url = 'https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential';
        url +="&appid=" + appid;
        url +="&secret=" + appSecret;
        let options = {url: url,method: "POST",}
        request(options,(error, response, body)=>{
            console.log('------------------getAccessToken-----------------')
            console.log(body)
            console.log('------------------getAccessToken-----------------')
            try {
                resolve(JSON.parse(body).access_token)
            }catch (e) {
                resolve('')
            }
        })
    })
}

// 獲取小程序二維碼請(qǐng)求腔寡，適用于需要的碼數(shù)量較少的業(yè)務(wù)場(chǎng)景。通過(guò)該接口生成的小程序碼神得，永久有效腹泌，有數(shù)量限制
const createQrcodeRequest = (token,subData) =>{
    return new Promise((resolve, reject) => {
        const url = 'https://api.weixin.qq.com/cgi-bin/wxaapp/createwxaqrcode?access_token='+ token;
        const options = {
            url:url,
            method: "POST",
            form:JSON.stringify(subData),
            encoding:"binary" // 二進(jìn)制流
        };
        request(options,(error, response, body)=>{
            let src = toBase64(body)
            console.log('------------------createQrcodeRequest-----------------')
            console.log(src)
            console.log('------------------createQrcodeRequest-----------------')
            resolve(src);
        })
    })
}

// 獲取小程序碼請(qǐng)求, 適用于需要的碼數(shù)量較少的業(yè)務(wù)場(chǎng)景墅茉。通過(guò)該接口生成的小程序碼，永久有效鲸伴，有數(shù)量限制
const getWxCodeRequest = (token,subData) => {
    return new Promise((resolve, reject) => {
        const url = 'https://api.weixin.qq.com/wxa/getwxacode?access_token='+ token;
        const options = {
            url:url,
            method: "POST",
            form:JSON.stringify(subData),
            encoding:"binary" // 二進(jìn)制流
        }
        request(options,(error, response, body)=>{
            let src = toBase64(body);
            console.log('------------------getWxCodeRequest-----------------')
            console.log(src)
            console.log('------------------getWxCodeRequest-----------------')
            resolve(src);
        })
    })
}

// 獲取小程序碼請(qǐng)求丐箩，適用于需要的碼數(shù)量極多的業(yè)務(wù)場(chǎng)景。通過(guò)該接口生成的小程序碼此改，永久有效趾撵，數(shù)量暫無(wú)限制。
const getUnlimitedCodeRequest = (token,subData) => {
    return new Promise((resolve, reject) => {
        const url = 'https://api.weixin.qq.com/wxa/getwxacodeunlimit?access_token='+ token;
        const options = {
            url:url,
            method: "POST",
            form:JSON.stringify(subData),
            encoding:"binary" // 二進(jìn)制流
        }
        request(options,(error, response, body)=>{
            let src = toBase64(body);
            console.log('------------------getUnlimitedCodeRequest-----------------')
            console.log(src)
            console.log('------------------getUnlimitedCodeRequest-----------------')
            resolve(src);
        })
    })
}

// 創(chuàng)建小程序二維碼共啃，返回base64地址,適用于需要的碼數(shù)量較少的業(yè)務(wù)場(chǎng)景占调。通過(guò)該接口生成的小程序碼，永久有效移剪，有數(shù)量限制
const getBaseCode = () => {
    return new Promise((resolve, reject) => {
        getAccessToken(appid,appSecret).then(token =>{
            let creatOptions = {token:token,path:"pages/index/index",width:300}
            createQrcodeRequest(token,creatOptions).then(base64 =>{
                resolve(base64)
            })
        })
    })
}

// 獲取小程序碼究珊，返回base64地址, 適用于需要的碼數(shù)量較少的業(yè)務(wù)場(chǎng)景。通過(guò)該接口生成的小程序碼纵苛，永久有效剿涮，有數(shù)量限制
const getWxaCode = () => {
    return new Promise((resolve, reject) => {
        getAccessToken(appid,appSecret).then(token =>{
            let getOptions = {
                path:"pages/index/index", // 掃碼進(jìn)入的小程序頁(yè)面路徑
                width:300, // 小程序碼大小
                line_color:{"r":"17","g":"171","b":"153"}, // 小程序碼線(xiàn)條顏色
                is_hyaline:false //是否需要透明底色，為 true 時(shí)攻人，生成透明底色的小程序碼
            }
            getWxCodeRequest(token,getOptions).then(base64 =>{
                resolve(base64)
            })
        })
    })
}

// 獲取小程序碼取试，返回base64地址, 適用于需要的碼數(shù)量極多的業(yè)務(wù)場(chǎng)景。通過(guò)該接口生成的小程序碼贝椿，永久有效想括，數(shù)量暫無(wú)限制陷谱。
const getUnlimitedWxaCode = () => {
    return new Promise((resolve, reject) => {
        getAccessToken(appid,appSecret).then(token =>{
            let getOptions = {
                path:"pages/index/index", // 掃碼進(jìn)入的小程序頁(yè)面路徑
                width:300, // 小程序碼大小
                scene:"Echonessy",// 標(biāo)識(shí)
                line_color:{"r":"17","g":"171","b":"153"}, // 小程序碼線(xiàn)條顏色
                is_hyaline:false //是否需要透明底色烙博，為 true 時(shí)，生成透明底色的小程序碼
            }
            getUnlimitedCodeRequest(token,getOptions).then(base64 =>{
                resolve(base64)
            })
        })
    })
}

module.exports = {
    getBaseCode:getBaseCode,
    getWxaCode:getWxaCode,
    getUnlimitedWxaCode:getUnlimitedWxaCode,
}