/* calc */
const ires=$('input_result');
const ores=$('output_result');
var iresdat="";
var oresdat="";
var calculated=0;

function calculatei() {
    //iresdat=iresdat.replace(/%/g,'/100*');
    if(iresdat.indexOf("%")!=-1) {
        if(lpara!=0) {
            var val1=iresdat.substr(llpara,ladd-llpara-1);
            var val2=iresdat.substr(ladd,lpara-ladd-2);
            //iresdat=iresdat.replace(pval1,"__pval1__");
            //iresdat=iresdat.replace(pval2,"__pval2__");
        } else {
            var val1=iresdat.substr(lladd,ladd-1);
            var val2=iresdat.substr(ladd,iresdat.length-ladd-1);
            //var val2=iresdat.substr(ladd,iresdat.length-1);
        }
        //alert(val1+"*"+val2+"/100");
        var sum2=evil(val1+"*"+val2+"/100");
       //alert(val1+"*"+val2+"/100");
        if(false!==sum2) {
            oresdat=iresdat;

            var tmpiresdat=iresdat.substr(0,ladd)+"%";
            if(lpara!=0) {
                tmpiresdat+=")";

                if(iresdat.length>lpara) {
                    llpara=lpara;
                }
                lpara=iresdat.length;
            }
            //var tmpiresdat=iresdat.substr(0,ladd)+"";
            iresdat=tmpiresdat.replace(/%/g,cact+sum2);

            ladd=0;
            lladd=0;
            //lpara=0;
            //llpara=0;
            }
    } else {
        calculated=evil(iresdat);

        if(false!==sum2) {
            oresdat=iresdat;

            try {
                iresdat=calculated.toString();
            } catch(e) {
                iresdat="0";
            }

            cact="";
            ladd=0;
            lladd=0;
            lpara=0;
            llpara=0;
        }
    }
     printCalc();
}

function clearhist() {
    $('output_history').innerHTML="";
    histidx=0;
}

var histidx=0;
var maxhist=50;
function printCalc() {
    //var history=[];
    //history.push(ores.innerHTML);
    //$('output_history').insertAdjacentHTML('beforeend',oresdat+" = "+iresdat+"<br /><hr />");
    if($('chist'+histidx)) {
        $('chist'+histidx).parentNode.removeChild($('chist'+histidx));
    }
    if($('output_history').innerHTML=="") {
        $('output_history').insertAdjacentHTML('beforeend',"<div style=\"font-size: 10pt;\"><a href=\"javascript:clearhist();\" target=\"_self\">[Clear history]</a></div>");
    }
    $('output_history').insertAdjacentHTML('beforeend',"<div id=\"chist"+histidx+"\">"+oresdat+" = "+iresdat+"</div>");
    histidx++;
    if(histidx>maxhist) {
        histidx=0;
    }

    $('output_history_wrap').scrollTop=$('output_history_wrap').scrollHeight;


    ores.innerHTML=(oresdat!="")?oresdat:"&nbsp;";
    ires.innerHTML=(iresdat!="")?iresdat:"0";
}

function updateo() {
    if(iresdat!="") {
        ores.innerHTML=iresdat;
    } else {
        ores.innerHTML="&nbsp;";
    }
    if(typeof calculated!=='undefined') {
        ires.innerHTML=calculated.toString();
    } else {
        ires.innerHTML="0";
    }
}

var cmode=0; // 0=insert, 1=addition/subtraction/multiply/divide = next insert calculates
var cact=""; // x / - +
var pmode="" // ( = 0 ) = 1

    // percent and equal are active, back, paranthesis and dot are inserts
    //
function actcheck() {
    if(iresdat=="0") iresdat="";

    var bool=false;
    if(cact!="") {
        //iresdat+=cact;
        bool=true;
    }
    return bool;
}

function press_btn9() {
    var exec=actcheck();
    exec=false;
    cact="";
    iresdat+="9";
    if(exec) calculatei();
    else updateo();
}
function press_btn8() {
    var exec=actcheck();
    exec=false;
    cact="";
    iresdat+="8";
    if(exec) calculatei();
    else updateo();
}
function press_btn7() {
    var exec=actcheck();
    exec=false;
    cact="";
    iresdat+="7";
    if(exec) calculatei();
    else updateo();
}
function press_btn6() {
    var exec=actcheck();
    exec=false;
    cact="";
    iresdat+="6";
    if(exec) calculatei();
    else updateo();
}
function press_btn5() {
    var exec=actcheck();
    exec=false;
    cact="";
    iresdat+="5";
    if(exec) calculatei();
    else updateo();
}
function press_btn4() {
    var exec=actcheck();
    exec=false;
    cact="";
    iresdat+="4";
    if(exec) calculatei();
    else updateo();
}
function press_btn3() {
    var exec=actcheck();
    exec=false;
    cact="";
    iresdat+="3";
    if(exec) calculatei();
    else updateo();
}
function press_btn2() {
    var exec=actcheck();
    exec=false;
    cact="";
    iresdat+="2";
    if(exec) calculatei();
    else updateo();
}
function press_btn1() {
    var exec=actcheck();
    exec=false;
    cact="";
    iresdat+="1";
    if(exec) calculatei();
    else updateo();
}
function press_btn0() {
    var exec=actcheck();
    exec=false;
    cact="";
    iresdat+="0";
    if(exec) calculatei();
    else updateo();
}

function press_btnAC() {
    cact="";
    iresdat="";
    oresdat="";
    cmode=0;
    pmode="";
    calculated=0;
    ladd=0;
    lladd=0;
    lpara=0;
    llpara=0;

    //ires.innerHTML="";
    //ores.innerHTML="";
    calculatei();
}
function press_btnPara() {
    //var exec=actcheck();
    var exec=false;
    if(pmode==0) {
        if(cact!="") {
            cact="";
            iresdat+="("; 
            pmode=1;
        } else if(iresdat=="" || iresdat=="0" || iresdat=="&nbsp;") {
            iresdat="("; 
            pmode=1;
        }
    } else {
        cact="";
        iresdat+=")"; 
        pmode=0;
    }
    if(iresdat.length>lpara) {
        llpara=lpara;
    }
    lpara=iresdat.length;

    if(exec) calculatei();
    else updateo();
}
function press_btnPer() {
    //iresdat="%"+iresdat;
    //updateo();
    //calculatei();
    if(ladd>0 && cact=="") {
        var exec=actcheck();
        if(exec) {
            iresdat=iresdat.substr(0,iresdat.length-1);
        }
        //cact="%";
        iresdat+="%";
        if(pmode==1) {
            //cact="";
            iresdat+=")";
            pmode=0;

            if(iresdat.length>lpara) {
                llpara=lpara;
            }
            lpara=iresdat.length;
            }
        calculatei();
    }
    //updateo();
}
function press_btnDiv() {
    //updateo();
    var exec=actcheck();
    if(exec) {
        iresdat=iresdat.substr(0,iresdat.length-1);
    }
    cact="/";
    iresdat+="/";
    if(iresdat.length>ladd) {
        lladd=ladd;
    }
    ladd=iresdat.length;
    //if(exec) calculatei();
    updateo();
}
function press_btnMul() {
    //updateo();
    var exec=actcheck();
    if(exec) {
        iresdat=iresdat.substr(0,iresdat.length-1);
    }
    cact="*";
    iresdat+="*";
    if(iresdat.length>ladd) {
        lladd=ladd;
    }
    ladd=iresdat.length;
    //if(exec) calculatei();
    updateo();
}
function press_btnSub() {
    //updateo();
    var exec=actcheck();
    if(exec) {
        iresdat=iresdat.substr(0,iresdat.length-1);
    }
    cact="-";
    iresdat+="-";
    if(iresdat.length>ladd) {
        lladd=ladd;
    }
    ladd=iresdat.length;
    //if(exec) calculatei();
    updateo();
}
function press_btnAdd() {
    //updateo();
    var exec=actcheck();
    if(exec) {
        iresdat=iresdat.substr(0,iresdat.length-1);
    }
    cact="+";
    iresdat+="+";
    if(iresdat.length>ladd) {
        lladd=ladd;
    }
    ladd=iresdat.length;
    //if(exec) calculatei();
    updateo();
}

function press_btnDot() {
    //iresdat+=".";
    //updateo();
    //var exec=actcheck();
    var exec=false;
    if(iresdat.substr(iresdat.length-1)!=".") {
        cact="";
        iresdat+=".";
    }
    if(exec) calculatei();
    else updateo();
}
function press_btnBackspace() {
    //var exec=actcheck();
    //cact="";
    var exec=false;
    cact="";
    if(iresdat.length>0) {
        var lch=iresdat.substr(iresdat.length-1,1);
        if(lch==")") {
            pmode=1;
            //cact=lch;
            lpara=iresdat.length-1;
            llpara=iresdat.lastIndexOf("(");
        } else if(lch=="(") {
            pmode=0;
            lpara=iresdat.length-1;
            llpara=0;
        }
        iresdat=iresdat.substr(0,iresdat.length-1);

        lch=iresdat.substr(iresdat.length-1,1);
        if(lch=="*" || lch=="/" || lch=="+" || lch=="-") {
            cact=lch;
            ladd=iresdat.length-1;
            lladd=0;
            for(var i=iresdat.length-1;i>=0;i--) {
                if(i<ladd) {
                    var ich=iresdat.substr(i,1);
                    if(ich=="*" || ich=="/" || ich=="+" || ich=="-") {
                        lladd=i;
                        break;
                    }
                }
            }
        }
    }
    if(exec) calculatei();
    else updateo();
}
function press_btnEqual() {
    var exec=actcheck();
    cact="";
    calculatei();
}

$('btn_9').addEventListener("click",press_btn9);
$('btn_8').addEventListener("click",press_btn8);
$('btn_7').addEventListener("click",press_btn7);
$('btn_6').addEventListener("click",press_btn6);
$('btn_5').addEventListener("click",press_btn5);
$('btn_4').addEventListener("click",press_btn4);
$('btn_3').addEventListener("click",press_btn3);
$('btn_2').addEventListener("click",press_btn2);
$('btn_1').addEventListener("click",press_btn1);
$('btn_0').addEventListener("click",press_btn0);
$('btn_ac').addEventListener("click",press_btnAC);
$('btn_para').addEventListener("click",press_btnPara);
var ladd=0;
var lladd=0;
var lpara=0;
var llpara=0;
$('btn_per').addEventListener("click",press_btnPer);
$('btn_divid').addEventListener("click",press_btnDiv);
$('btn_multi').addEventListener("click",press_btnMul);
$('btn_subtr').addEventListener("click",press_btnSub);
$('btn_addit').addEventListener("click",press_btnAdd);
$('btn_dot').addEventListener("click",press_btnDot);
$('btn_back').addEventListener("click",press_btnBackspace);
$('btn_equal').addEventListener("click",press_btnEqual);

function evil(fn) {
    try {
        return new Function('return ' + fn)();
    } catch(e) {
        alert("error" + e);
        return false;
    }
}