var clipboard = new ClipboardJS('.btn-copy');
var xelem = document.getElementById("d");
var sel1elem = document.getElementById("from");
var sel2elem = document.getElementById("to");
var yelem = document.getElementById("y");
var calgroup = document.getElementById("calgroup");
var cal1elem = document.getElementById("cal1");
var cal2elem = document.getElementById("cal2");
window.addEventListener("DOMContentLoaded", function () {
    calgroup.style.display = "none";
    var params = GetURLParams();
    /*
    if (Object.keys(params).length > 0 && params.d != "") {
        xelem.value = params.d;
        sel1elem.selectedIndex = params.from - 2;
        sel2elem.selectedIndex = params.to - 2;
        onconvert()
    }
    */
    params = JSON.parse(JSON.stringify(params))
    if (Object.keys(params).length > 0) {
        console.log('params', params)
        if (params.d) {
            xelem.value = params.d;
        }
        if (params.from) {
            sel1elem.selectedIndex = params.from - 2;
        }
        if (params.to) {
            sel2elem.selectedIndex = params.to - 2;
        }

        if (params.d && params.from && params.to) {
            onconvert()
        }
    }
});

function GetURLParams() {
    var url = window.location.href;
    var regex = /[?&]([^=#]+)=([^&#]*)/g,
        params = {},
        match;
    while (match = regex.exec(url)) {
        params[match[1]] = match[2]
    }
    return params
}

function swap() {
    var i1 = sel1elem.selectedIndex;
    var i2 = sel2elem.selectedIndex;
    sel1elem.selectedIndex = i2;
    sel2elem.selectedIndex = i1;
    xelem.value = yelem.value;
    yelem.value = ""
}

function base2decimal(x, dec, b) {
    var txt = "(" + x + ")<sub>" + b.toString() + "</sub> = ";
    var d, e, minus = false;
    var len = x.length;
    if (x[0] == "-") {
        txt += "-[";
        x = x.substr(1);
        len--;
        minus = true
    }
    var idot = x.indexOf(".");
    if (idot >= 0) {
        x = x.substring(0, idot) + x.substring(idot + 1, len);
        len--
    } else idot = len;
    for (var i = 0; i < len; i++) {
        d = parseInt(x[i], b);
        e = idot - i - 1;
        e = e.toString();
        txt += "(" + d + " × " + b + "<sup>" + e + "</sup>)";
        if (i < len - 1) txt += " + "
    }
    if (minus) txt += "]";
    txt += " = (" + dec + ")<sub>10</sub>";
    document.getElementById("cal1txt").innerHTML = txt
}

function digits_after_period(x) {
    f = x.toString();
    i = f.indexOf('.');
    len = f.length - i - 1;
    return len
}

function decimal2base(dec, y, b) {
    var row, txt = "";
    document.getElementById("cal2tbl").getElementsByTagName('tbody')[0].innerHTML = "";
    if (dec < 0) dec = -dec;
    dec = dec.toString();
    var id = dec.indexOf(".");
    var nd = y.length - y.indexOf(".") - 1;
    if (nd > 6) nd = 6;
    if (id >= 0 && nd > 0) {
        txt = "将目标基数乘以结果的小数位数(最高可达6位数):<br>";
        txt += "floor(" + dec + "&times;" + b + "<sup>" + nd + "</sup>) = ";
        dec = Math.floor(dec * Math.pow(b, nd));
        txt += dec
    }
    document.getElementById("cal2dec").innerHTML = txt;
    for (var n = dec, k = 0; n >= 1; k++) {
        row = "<tr>";
        row += "<td>" + n + "/" + b + "</td>";
        row += "<td>" + Math.floor(n / b) + "</td>";
        row += "<td>" + (n % b).toFixed() + "</td>";
        row += "<td>" + k + "</td>";
        row += "</tr>";
        n = Math.floor(n / b);
        var tableRef = document.getElementById('cal2tbl').getElementsByTagName('tbody')[0];
        var newRow = tableRef.insertRow(k);
        newRow.innerHTML = row
    }
    document.getElementById("cal2result").innerHTML = "= (" + y + ")<sub>" + b + "</sub>"
}

function onconvert() {
    var x = xelem.value;
    var b1 = sel1elem.selectedIndex + 2;
    var b2 = sel2elem.selectedIndex + 2;
    try {
        var y = new BigNumber(x, b1);
        xelem.style.background = "white"
    } catch (err) {
        xelem.style.background = "#fff0f0";
        yelem.value = "";
        return
    }
    var dec = y.toString(10);
    y = y.toString(b2).toUpperCase();
    yelem.value = y;
    var yd = yelem.value.match(/[\dA-Z]/g);
    var ylabel = "转换结果：";
    if (yd != null) ylabel += " (" + yd.length + " 位)";
    document.getElementById("ylabel").innerHTML = ylabel;
    document.getElementById("b1txt").innerHTML = b1;
    document.getElementById("b2txt").innerHTML = b2;
    base2decimal(x, dec, b1);
    decimal2base(dec, y, b2);
    if (b1 == 10) cal1elem.style.display = "none";
    else cal1elem.style.display = "block";
    if (b2 == 10) cal2elem.style.display = "none";
    else cal2elem.style.display = "block";
    calgroup.style.display = "block"
}

function onrst() {
    calgroup.style.display = "none"
}