module.exports = {
    // buffer 转16进制
    buf2hex:function (buffer) {
        // create a byte array (Uint8Array) that we can use to read the array buffer
        const byteArray = new Uint8Array(buffer);
        // for each element, we want to get its two-digit hexadecimal representation
        const hexParts = [];
        for(let i = 0; i < byteArray.length; i++) {
            // convert value to hexadecimal
            const hex = byteArray[i].toString(16);
            // pad with zeros to length 2
            const paddedHex = ('00' + hex).slice(-2);
            // push to array
            hexParts.push(paddedHex);
        }

        // join all the hex values of the elements into a single string
        return hexParts.join('');
    },
    // 足压数据补齐点位为60*60 并进行点扩散
    setPressureData:function (data) {
        let dataAll = []
        // 补到之前  60*60 个点位
        for (let j =0;j<60;j++) {
            dataAll[j] = []
            for (let k =0;k<60;k++) {
                if(typeof (data[j]) == 'undefined') {
                    dataAll[j][k] = 0
                } else {
                    if(typeof (data[j][k]) == 'undefined') {
                        dataAll[j][k] = 0
                    } else {
                        dataAll[j][k] = data[j][k]
                    }
                }
            }
        }
        return pressureDataProcess(dataAll,1,4)
    },
    // arrayBuffer 转string
    ab2Ascii(buffer) {
        var str = Array.prototype.map.call(
            new Uint8Array(buffer),
            function (bit) {
                return String.fromCharCode(bit);
            }
        )
        return str.join('');
    },
    // arrayBuffer to buffer
    toBuffer(ab) {
        var buf = new Buffer(ab.byteLength);
        var view = new Uint8Array(ab);
        for (var i = 0; i < buf.length; ++i) {
            buf[i] = view[i];
        }
        return buf;
    },
    getLogDate() {
        var myDate = new Date();
        return  (myDate.getYear()-100).toString()+ '-' + addStrZero(myDate.getMonth()+1) + '-' + addStrZero(myDate.getDate()) +'_'+addStrZero(myDate.getHours())
    }
}
function addStrZero(num) {
    return  num < 10 ? '0'+num.toString():num.toString()
}
function pressureDataProcess(a,scale,size) {
    var height = 60;
    var width = 60;
    var newHeight = 60*scale;
    var newWidth = 60*scale;
    var u =0.0;
    var v = 0.0;
    var x = 0.0;
    var y = 0.0;
    var m = 0;
    var n = 0;
    let temp = new Array()
    let rearr = []
    for(let i = 0;i<newHeight;++i) {
        temp[i] = new Array()
        for(let j=0;j<newWidth;++j) {
            y = i/scale;
            x = j/scale;
            m = parseInt(y);
            n = parseInt(x);
            v = y-m;
            u = x-n;
            let tt = {}
            if(m<height-1 &&n<width-1){
                temp[i][j] = parseInt((1.0-v)*((1.0-u)*a[m][n]+u*a[m][n+1])
                    + v*((1.0-u)*a[m+1][n] + u*a[m+1][n+1])
                )
            } else {
                temp[i][j] = a[m][n]
            }
            tt.x = i*size
            tt.y = j*size
            if(temp[i][j]>0) {
                tt.value = temp[i][j]
                rearr.push(tt)
            }
        }
    }
    return rearr
}