@antmove/alipay-wx/__api/utils.js

transform alipay miniprogram to wx miniprogram tool.

const logUtils = require('./log.js');
let hasProxy = typeof Proxy !== 'undefined';
let _Proxy = function () {};

if (hasProxy) _Proxy = Proxy;

module.exports = {
    ...logUtils,
    /**
     * defineGetter
     */
    defineGetter (obj = {}, descObj = {}, cb = () => {}) {
        if (!hasProxy) {
            return obj;
        } 
        return new _Proxy(obj, {
            get (target, attr) {
                if (typeof attr === 'string' && descObj[attr] && descObj[attr].type === 0) {
                    cb && cb(target, attr);
                }

                return target[attr];
            }
        });
    },
    /**
     * sourceObj : 要操作对象
     * wxAttr: 微信key值
     * alipayAttr: 支付宝key值
     **/
    objectMap (sourceObj = {}, wxAttr, alipayAttr) {
        if (!hasProxy) {
            Object.defineProperty(sourceObj, wxAttr, {
                get () {
                    return sourceObj[alipayAttr];
                }
            });
    
            return sourceObj;
        }
        return new _Proxy(sourceObj, {
            get (target, attr) {
                if (attr === wxAttr) {
                    return target[alipayAttr];
                }
            }
        });
    },
    // 类型转换
    changeType (str) {
        let hexA = new Array();
        if (typeof attr === 'string') {
            // 十六进制字符串转字节数组
            var pos = 0;
            var len = str.length;
            if (len % 2 !== 0) {
                return null;
            }
            len /= 2;
            for (var i = 0; i < len; i++) {
                var s = str.substr(pos, 2);
                var v = parseInt(s, 16);
                hexA.push(v);
                pos += 2;
            }
            return hexA;
        }
    },
    // https://github.com/wandergis/coordtransform/blob/master/index.js
    wgs84togcj02 (lng, lat) {
        var ee = 0.00669342162296594323;
        var a = 6378245.0;

        lat = Number(lat);
        lng = Number(lng);

        if (out_of_china(lng, lat)) {
            return [lng, lat];
        }

        var dlat = transformlat(lng - 105.0, lat - 35.0);
        var dlng = transformlng(lng - 105.0, lat - 35.0);
        var radlat = lat / 180.0 * Math.PI;
        var magic = Math.sin(radlat);
        magic = 1 - ee * magic * magic;
        var sqrtmagic = Math.sqrt(magic);
        dlat = (dlat * 180.0) / ((a * (1 - ee)) / (magic * sqrtmagic) * Math.PI);
        dlng = (dlng * 180.0) / (a / sqrtmagic * Math.cos(radlat) * Math.PI);
        var mglat = lat + dlat;
        var mglng = lng + dlng;

        return [mglng, mglat];
    },

    ab2hex (buffer) {
        const hexArr = Array.prototype.map.call(
            new Uint8Array(buffer),
            function (bit) {
                return ('00' + bit.toString(16)).slice(-2);
            }
        );
        return hexArr.join('');
    },
    /**
     * change attr for object
     * replace attr by newAttr
     */
    changeObjAttr (obj = {}, attr, newAttr) {
        if (obj[attr] !== undefined) {
            obj[newAttr] = obj[attr];
            delete obj[attr];
        } else {
            console.warn(`${attr} attribute is missing!`);
        }

        return obj;
    }
};

function out_of_china (lng, lat) {
    // 纬度3.86~53.55,经度73.66~135.05
    return !(lng > 73.66 && lng < 135.05 && lat > 3.86 && lat < 53.55);
}

function transformlat (lng, lat) {
    var ret = -100.0 + 2.0 * lng + 3.0 * lat + 0.2 * lat * lat + 0.1 * lng * lat + 0.2 * Math.sqrt(Math.abs(lng));
    ret += (20.0 * Math.sin(6.0 * lng * Math.PI) + 20.0 * Math.sin(2.0 * lng * Math.PI)) * 2.0 / 3.0;
    ret += (20.0 * Math.sin(lat * Math.PI) + 40.0 * Math.sin(lat / 3.0 * Math.PI)) * 2.0 / 3.0;
    ret += (160.0 * Math.sin(lat / 12.0 * Math.PI) + 320 * Math.sin(lat * Math.PI / 30.0)) * 2.0 / 3.0;
    return ret;
}

function transformlng (lng, lat) {
    var ret = 300.0 + lng + 2.0 * lat + 0.1 * lng * lng + 0.1 * lng * lat + 0.1 * Math.sqrt(Math.abs(lng));
    ret += (20.0 * Math.sin(6.0 * lng * Math.PI) + 20.0 * Math.sin(2.0 * lng * Math.PI)) * 2.0 / 3.0;
    ret += (20.0 * Math.sin(lng * Math.PI) + 40.0 * Math.sin(lng / 3.0 * Math.PI)) * 2.0 / 3.0;
    ret += (150.0 * Math.sin(lng / 12.0 * Math.PI) + 300.0 * Math.sin(lng / 30.0 * Math.PI)) * 2.0 / 3.0;
    return ret;
}