//Global variables
var winCal;
var dtToday=new Date();
var Cal;
var docCal;
var MonthName=["Sausis", "Vasaris", "Kovas", "Balandis", "Gegužė","Birželis", "Liepa",
    "Rugpjūtis", "Rugsėjis", "Spalis", "Lapkritis", "Gruodis"];
var WeekDayName=["Pirmadienis","Antradienis","Trečiadienis","Ketvirtadienis","Penktadienis","Šeštadienis","Sekmadienis"];    
var exDateTime;//Existing Date and Time

//Configurable parameters
var cnTop="200";//top coordinate of calendar window.
var cnLeft="400";//left coordinate of calendar window
var WindowTitle ="Datos pasirinkimas";//Date Time Picker title.
var WeekChar=2;//number of character for week day. if 2 then Mo,Di,Mi. if 3 then Mon,Die,Mit.
var DateSeparator=".";//Date Separator, you can change it to "/" if you want.
var TimeMode=24;//default TimeMode value. 12 or 24
var ShowLongMonth=true;//Show long month name in Calendar header. example: "January".
var ShowMonthYear=false;//Show Month and Year in Calendar header.
//end Configurable parameters
//end Global variable

function NewCal(pCtrl,pFormat,pShowTime,pTimeMode){
    Cal=new Calendar(dtToday);
    if ((pShowTime!=null) && (pShowTime)){
        Cal.ShowTime=true;
        if ((pTimeMode!=null) &&((pTimeMode=='12')||(pTimeMode=='24')))
            TimeMode=pTimeMode;     
    }   
    if (pCtrl!=null)
        Cal.Ctrl=pCtrl;
    if (pFormat!=null)
        Cal.Format=pFormat.toUpperCase();
    
    exDateTime=document.getElementById(pCtrl).value;
    if (exDateTime!="")//Parse Date String
    {
        var Sp1;//Index of Date Separator 1
        var Sp2;//Index of Date Separator 2 
        var tSp1;//Index of Time Separator 1
        var tSp1;//Index of Time Separator 2
        var strMonth;
        var strDate;
        var strYear;
        var intMonth;
        var YearPattern;
        var strHour;
        var strMinute;
        var strSecond;
        //parse month
        Sp1=exDateTime.indexOf(DateSeparator,0)
        Sp2=exDateTime.indexOf(DateSeparator,(parseInt(Sp1)+1));
        
        if ((Cal.Format=="DDMMYYYY") || (Cal.Format=="DDMMMYYYY")){
            strMonth=exDateTime.substring(Sp1+1,Sp2);
            strDate=exDateTime.substring(0,Sp1);
            strYear=exDateTime.substring(Sp2+1,Sp2+5);
        }else if ((Cal.Format=="MMDDYYYY") || (Cal.Format=="MMMDDYYYY")){
            strMonth=exDateTime.substring(0,Sp1);
            strDate=exDateTime.substring(Sp1+1,Sp2);
            strYear=exDateTime.substring(Sp2+1,Sp2+5);
        }else if ((Cal.Format=="YYYYMMDD") || (Cal.Format=="YYYYMMMDD")){
            strMonth=exDateTime.substring(Sp1+1,Sp2);
            strDate=exDateTime.substring(Sp2+1,Sp2+3);
            strYear=exDateTime.substring(0,Sp1);
        }else if (Cal.Format=="MMDD"){
            strMonth=exDateTime.substring(0,Sp1);
            strDate=exDateTime.substring(Sp1+1,Sp1+3);
        } else {
            alert("ERROR: Unsupported date format '"+Cal.Format+"'!");
        }

        if (isNaN(strMonth))
            intMonth=Cal.GetMonthIndex(strMonth);
        else
            intMonth=parseInt(strMonth,10)-1;   
        if ((parseInt(intMonth,10)>=0) && (parseInt(intMonth,10)<12))
            Cal.Month=intMonth;
        //end parse month
        //parse Date
        if ((parseInt(strDate,10)<=Cal.GetMonDays()) && (parseInt(strDate,10)>=1))
            Cal.Date=strDate;
        //end parse Date
        //parse year
        YearPattern=/^\d{4}$/;
        if (YearPattern.test(strYear))
            Cal.Year=parseInt(strYear,10);
        //end parse year
        //parse time
        if (Cal.ShowTime==true)
        {
            tSp1=exDateTime.indexOf(":",0)
            tSp2=exDateTime.indexOf(":",(parseInt(tSp1)+1));
            strHour=exDateTime.substring(tSp1,(tSp1)-2);
            Cal.SetHour(strHour);
            strMinute=exDateTime.substring(tSp1+1,tSp2);
            Cal.SetMinute(strMinute);
            strSecond=exDateTime.substring(tSp2+1,tSp2+3);
            Cal.SetSecond(strSecond);
        }   
    }
    winCal=window.open("","DateTimePicker","toolbar=0,status=0,menubar=0,fullscreen=no,width=215,height=155,resizable=0,status=1,top="+cnTop+",left="+cnLeft);
    docCal=winCal.document;
    RenderCal();
}

function RenderCal()
{
    var vCalHeader;
    var vCalData;
    var vCalTime;
    var i;
    var j;
    var SelectStr;
    var vDayCount=0;
    var vFirstDay;

    docCal.open();
    docCal.writeln("<html><head><title>"+WindowTitle+"</title>");
    docCal.writeln("<script>var winMain=window.opener;</script>");
    docCal.writeln("<LINK REL=StyleSheet HREF=\"style_date.css\" type=\"text/css\">");
    docCal.writeln("</head><body class=\"cldr\"><form name='Calendar'>");
    //Month Selector
    vCalHeader="<table border=0 width='100%' cellpadding=0 cellspacing=0 class=head><tr><td>";
    vCalHeader+="<td><a href=\"javascript:winMain.Cal.DecYear();winMain.RenderCal()\"><img src=\"img/js/prev_year.gif\" width=16 height=16 border=0 alt=\"Previuos year\" vspace=2 hspace=2></a><a href=\"javascript:winMain.Cal.DecMonth();winMain.RenderCal()\"><img src=\"img/js/prev.gif\" width=16 height=16 border=0 alt=\"Previuos month\" vspace=2 hspace=1></a></td>";
    vCalHeader+="<td align=center nowrap><select name=\"MonthSelector\" onChange=\"javascript:winMain.Cal.SwitchMth(this.selectedIndex);winMain.RenderCal();\">\n";
    for (i=0;i<12;i++) {
        if (i==Cal.Month) SelectStr="Selected";
        else SelectStr="";  
        vCalHeader+="<option "+SelectStr+" value >"+MonthName[i];
    }
    vCalHeader+="</select>";
    //Year selector
    vCalHeader+="<select name=\"YearSelector\" onChange=\"javascript:winMain.Cal.SwitchYear(this.value);winMain.RenderCal();\">\n";
    for (i=Cal.Year - 60;i<Cal.Year+10;i++) {
        if (i==Cal.Year) SelectStr="Selected";
        else SelectStr="";
        vCalHeader+="<option "+SelectStr+" value="+i+">"+i;
    }
    vCalHeader+="</select></td>";
    vCalHeader+="<td align=right><a href=\"javascript:winMain.Cal.IncMonth();winMain.RenderCal()\"><img src=\"img/js/next.gif\" width=16 height=16 border=0 alt=\"next Month\" vspace=2 hspace=1></a><a href=\"javascript:winMain.Cal.IncYear();winMain.RenderCal()\"><img src=\"img/js/next_year.gif\" width=16 height=16 border=0 alt=\"next year\" vspace=2 hspace=2></a></td></tr></table>";
    vCalHeader+="<table cellpadding=0 cellspacing=0 width='100%' border=0 class=main>\n";
    //Calendar header shows Month and Year
    if (ShowMonthYear)
        vCalHeader+="<tr><td colspan=7 class=MonthYearColor>"+Cal.GetMonthName(ShowLongMonth)+" "+Cal.Year+"</td></tr>\n";
    //Week day header
    vCalHeader+="<tr class=WeekHeadColor>";
    for (i=0;i<7;i++) vCalHeader+="<td>"+WeekDayName[i].substr(0,WeekChar)+"</td>";
    vCalHeader+="</tr>";    
    docCal.write(vCalHeader);
    
    //Calendar detail
    CalDate=new Date(Cal.Year,Cal.Month);
    CalDate.setDate(1);
    vFirstDay=CalDate.getDay();
    if (vFirstDay==0) vFirstDay = 7;
    vCalData="<tr>";
    for (i=0;i<vFirstDay-1;i++) {
        vCalData += GenCell();
        vDayCount=vDayCount+1;
    }
    for (j=1;j<=Cal.GetMonDays();j++){
        var strCell;
        vDayCount=vDayCount+1;
        if ((j==dtToday.getDate())&&(Cal.Month==dtToday.getMonth())&&(Cal.Year==dtToday.getFullYear()))
            if (j==Cal.Date) strCell=GenCell(j,"SelDateColor");
            else strCell=GenCell(j,"TodayColor");//Highlight today's date
        else {
            if (j==Cal.Date) {
                strCell=GenCell(j,"SelDateColor");
            } else {     
                if (vDayCount%7==6) strCell=GenCell(j,"SaturdayColor");
                else if (vDayCount%7==0) strCell=GenCell(j,"SundayColor");
                else strCell=GenCell(j,"WeekDayColor");
            }       
        }                       
        vCalData=vCalData+strCell;
        if((vDayCount%7==0)&&(j<Cal.GetMonDays())) {
            vCalData += "</tr><tr>";
        }
    }
    docCal.writeln(vCalData);   
    //Time picker
    if (Cal.ShowTime) {
        var showHour;
        showHour=Cal.getShowHour();     
        vCalTime="<tr>\n<td colspan=7 align=center>";
        vCalTime+="<input type=text name=hour maxlength=2 size=1 style=\"WIDTH: 22px\" value="+showHour+" onchange=\"javascript:winMain.Cal.SetHour(this.value)\">";
        vCalTime+=" : ";
        vCalTime+="<input type=text name=minute maxlength=2 size=1 style=\"WIDTH: 22px\" value="+Cal.Minutes+" onchange=\"javascript:winMain.Cal.SetMinute(this.value)\">";
        vCalTime+=" : ";
        vCalTime+="<input type=text name=second maxlength=2 size=1 style=\"WIDTH: 22px\" value="+Cal.Seconds+" onchange=\"javascript:winMain.Cal.SetSecond(this.value)\">";
        if (TimeMode==12) {
            var SelectAm =(parseInt(Cal.Hours,10)<12)? "Selected":"";
            var SelectPm =(parseInt(Cal.Hours,10)>=12)? "Selected":"";
            vCalTime+="<select name=\"ampm\" onchange=\"javascript:winMain.Cal.SetAmPm(this.options[this.selectedIndex].value);\">";
            vCalTime+="<option "+SelectAm+" value=\"AM\">AM</option>";
            vCalTime+="<option "+SelectPm+" value=\"PM\">PM<option>";
            vCalTime+="</select>";
        }   
        vCalTime+="</td></tr>";
        docCal.write(vCalTime);
    }   
    //end time picker
    docCal.writeln("</table><div align=center style=\"margin-top:5px;\"><input class=button style='cursor: pointer;' type=Button value=\"Šiandien\" onclick=\"javascript:winMain.Cal.SwitchMth("+dtToday.getMonth()+");winMain.Cal.SwitchYear("+dtToday.getFullYear()+");winMain.Cal.SwitchDate("+dtToday.getDate()+");winMain.RenderCal();\"> <input class=button type=Button value=\"Atšaukti\" onclick=\"javascript:window.close();\" style='cursor: pointer;'></div>");
    docCal.writeln("</form></body></html>");
    docCal.close();
}

function GenCell(pValue,pColor)//Generate table cell with value
{
    var PValue;
    var PCellStr;
    var vColor;
    var vTimeStr;
    
    if (pValue==null) PValue="";
    else PValue=pValue;
    
    if (pColor!=null) vColor="class=\""+pColor+"\"";
    else vColor=""; 
    
    if (Cal.ShowTime) {
        vTimeStr="winMain.document.getElementById('"+Cal.Ctrl+"').value+=' '+"+"winMain.Cal.getShowHour()"+"+':'+"+"winMain.Cal.Minutes"+"+':'+"+"winMain.Cal.Seconds";
        if (TimeMode==12)
            vTimeStr+="+' '+winMain.Cal.AMorPM";
    } else vTimeStr="";
    
    PCellStr="<td "+vColor+"><a href=\"javascript:winMain.document.getElementById('"+Cal.Ctrl+"').value='"+Cal.FormatDate(PValue)+"';"+vTimeStr+";winMain.document.getElementById('"+Cal.Ctrl+"').focus();window.close();\">"+PValue+"</a></td>";
    return PCellStr;
}

function Calendar(pDate,pCtrl){
    //Properties
    this.Date=pDate.getDate();//selected date
    this.Month=pDate.getMonth();//selected month number
    this.Year=pDate.getFullYear();//selected year in 4 digits
    this.Hours=pDate.getHours();    
    
    if (pDate.getMinutes()<10) this.Minutes="0"+pDate.getMinutes();
    else this.Minutes=pDate.getMinutes();
    
    if (pDate.getSeconds()<10) this.Seconds="0"+pDate.getSeconds();
    else this.Seconds=pDate.getSeconds();
        
    this.MyWindow=winCal;
    this.Ctrl=pCtrl;
    //this.Format="YYYYMMDD";//uppercase
    this.Format="YYYYMMDD";
    this.Separator=DateSeparator;
    this.ShowTime=false;
    if (pDate.getHours()<12) this.AMorPM="AM";
    else this.AMorPM="PM";  
}

function GetMonthIndex(shortMonthName){
    for (i=0;i<12;i++){
        if (MonthName[i].substring(0,3).toUpperCase()==shortMonthName.toUpperCase()) return i;
    }
}
Calendar.prototype.GetMonthIndex=GetMonthIndex;

function IncYear(){ Cal.Year++;}
Calendar.prototype.IncYear=IncYear;

function DecYear(){ Cal.Year--;}
Calendar.prototype.DecYear=DecYear;
    
function IncMonth(){    
    if (Cal.Month < 11)
        Cal.Month++;
    else {
        Cal.Month = 0;
        Cal.Year++;
    }
}
Calendar.prototype.IncMonth=IncMonth;

function DecMonth(){    
    if (Cal.Month > 0)
        Cal.Month--
    else {
        Cal.Month=11;
        Cal.Year--;
    }
}
Calendar.prototype.DecMonth=DecMonth;
    
function SwitchMth(intMth){ Cal.Month=intMth;}
Calendar.prototype.SwitchMth=SwitchMth;

function SwitchYear(Yr){Cal.Year=parseInt(Yr);}
Calendar.prototype.SwitchYear=SwitchYear;

function SwitchDate(Dt){Cal.Date=parseInt(Dt);}
Calendar.prototype.SwitchDate=SwitchDate;

function SetHour(intHour){  
    var MaxHour;
    var MinHour;
    if (TimeMode==24)
    {   MaxHour=23;MinHour=0}
    else if (TimeMode==12)
    {   MaxHour=12;MinHour=1}
    else
        alert("TimeMode can only be 12 or 24");     
    var HourExp=new RegExp("^\\d\\d$");
    if (HourExp.test(intHour) && (parseInt(intHour,10)<=MaxHour) && (parseInt(intHour,10)>=MinHour)){   
        if ((TimeMode==12) && (Cal.AMorPM=="PM")){
            if (parseInt(intHour,10)==12)
                Cal.Hours=12;
            else    
                Cal.Hours=parseInt(intHour,10)+12;
        }else if ((TimeMode==12) && (Cal.AMorPM=="AM")){
            if (intHour==12)
                intHour-=12;
            Cal.Hours=parseInt(intHour,10);
        }else if (TimeMode==24)
            Cal.Hours=parseInt(intHour,10); 
    }
}
Calendar.prototype.SetHour=SetHour;

function SetMinute(intMin){
    var MinExp=new RegExp("^\\d\\d$");
    if (MinExp.test(intMin) && (intMin<60))
        Cal.Minutes=intMin;
}
Calendar.prototype.SetMinute=SetMinute;

function SetSecond(intSec){ 
    var SecExp=new RegExp("^\\d\\d$");
    if (SecExp.test(intSec) && (intSec<60))
        Cal.Seconds=intSec;
}
Calendar.prototype.SetSecond=SetSecond;

function SetAmPm(pvalue){
    this.AMorPM=pvalue;
    if (pvalue=="PM"){
        this.Hours=(parseInt(this.Hours,10))+12;
        if (this.Hours==24)
            this.Hours=12;
    }else if (pvalue=="AM")
        this.Hours-=12; 
}
Calendar.prototype.SetAmPm=SetAmPm;

function getShowHour(){
    var finalHour;
    if (TimeMode==12){
        if (parseInt(this.Hours,10)==0){
            this.AMorPM="AM";
            finalHour=parseInt(this.Hours,10)+12;   
        }else if (parseInt(this.Hours,10)==12){
            this.AMorPM="PM";
            finalHour=12;
        }else if (this.Hours>12){
            this.AMorPM="PM";
            if ((this.Hours-12)<10)
                finalHour="0"+((parseInt(this.Hours,10))-12);
            else
                finalHour=parseInt(this.Hours,10)-12;   
        }else{
            this.AMorPM="AM";
            if (this.Hours<10)
                finalHour="0"+parseInt(this.Hours,10);
            else
                finalHour=this.Hours;   
        }
    }else if (TimeMode==24){
        if (this.Hours<10)
            finalHour="0"+parseInt(this.Hours,10);
        else    
            finalHour=this.Hours;
    }
    return finalHour;   
}               
Calendar.prototype.getShowHour=getShowHour;     

function GetMonthName(IsLong){
    var Month=MonthName[this.Month];
    if (IsLong)
        return Month;
    else
        return Month.substr(0,3);
}
Calendar.prototype.GetMonthName=GetMonthName;

function GetMonDays()//Get number of days in a month
{
    var DaysInMonth=[31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31];
    if (this.IsLeapYear()){
        DaysInMonth[1]=29;
    }   
    return DaysInMonth[this.Month]; 
}
Calendar.prototype.GetMonDays=GetMonDays;

function IsLeapYear(){
    if ((this.Year%4)==0){
        if ((this.Year%100==0) && (this.Year%400)!=0){
            return false;
        }else{
            return true;
        }
    }else{
        return false;
    }
}
Calendar.prototype.IsLeapYear=IsLeapYear;

function FormatDate(pDate){
    if (this.Format=="DDMMYYYY")
        return (leapZero(pDate)+DateSeparator+leapZero(this.Month+1)+DateSeparator+this.Year);
    else if (this.Format=="DDMMMYYYY")
        return (leapZero(pDate)+DateSeparator+this.GetMonthName(false)+DateSeparator+this.Year);
    else if (this.Format=="MMDDYYYY")
        return (leapZero(this.Month+1)+DateSeparator+leapZero(pDate)+DateSeparator+this.Year);
    else if (this.Format=="MMMDDYYYY")
        return (this.GetMonthName(false)+DateSeparator+leapZero(pDate)+DateSeparator+this.Year);
    else if (this.Format=="YYYYMMDD")
        return (this.Year+DateSeparator+leapZero(this.Month+1)+DateSeparator+leapZero(pDate));
    else if (this.Format=="YYYYMMMDD")
        return (this.Year+DateSeparator+this.GetMonthName(false)+DateSeparator+leapZero(pDate));
    else if (this.Format=="MMDD")
        return (leapZero(this.Month+1)+DateSeparator+leapZero(pDate));
}
Calendar.prototype.FormatDate=FormatDate;

function leapZero(nb){
    if (nb < 10) return "0" + nb;
    else return nb;
}