var filaMonth;

function showCalendar (img, cal, dt, frm,m,y,d) {
    if (document.getElementById) {
        var c = document.getElementById(cal);
        var i = document.getElementById(img);
        var f = document.getElementById(frm);
        calendar.calfrm = frm;
        calendar.cal = c;
        calendar.caldt = dt;
        calendar.calf = f;
        var my = f[dt + '_month'].value.split("-");
        y=my[0];m=my[1];d=f[ dt + '_day'].value;
        buildCal(y,m,d);
        var l=0; var t=0;
        aTag = i;
        do {
            aTag = aTag.offsetParent;
            l += aTag.offsetLeft;
            t += aTag.offsetTop;
        } while (aTag.offsetParent && aTag.tagName != 'body');
        var left =  i.offsetLeft + l;
        var top = i.offsetTop + t + i.offsetHeight + 2;
        c.style.position = "absolute";
        c.style.left = left+'px';
        c.style.top = top+'px';
        c.style.display="block";
    }
}

function closeCal() {
    calendar.cal.style.display='none';
}

function buildCal(y,m,d){
    var daysInMonth=[31,0,31,30,31,30,31,31,30,31,30,31];
    td=new Date();
    if (!y) y = td.getFullYear();
    if (!m) m = td.getMonth()+1;
    if (!d) d = td.getDate;
    var frm = calendar.calfrm;
    var dt = calendar.caldt;

    var mDate = new Date(y, m-1, 1);
    var firstMonthDay = mDate.getDay();
    daysInMonth[1]=(((mDate.getFullYear()%100!=0) && (mDate.getFullYear()%4==0)) || (mDate.getFullYear()%400==0))?29:28;

    var today = (y==td.getFullYear() && m==td.getMonth()+1)? td.getDate() : 0;
    var t='<table class="b_caltable" cellspacing="0"><tr class="b_calHeader">';
    var flm=td.getMonth()+1;var flyr=td.getFullYear();
    for(p=0;p<=10;p++){
        if (flm == m) {
            filaMonth = p;
        }
        flm++; if (flm>12) { flm=1;flyr++ }
    }
    t+='<td colspan="7">';
    if (filaMonth == 0) {
        t+='&nbsp;&lt;&nbsp;';
    }
    else {
        t+='<a href="javascript:prevMonth('+y+','+m+');" title="'+tr.prevMonth+'">&nbsp;&lt;&nbsp;</a>';
    }
    t+='&nbsp;<select name="ym" onchange="goMonth(this.options[this.selectedIndex].value)">';
    var mn=td.getMonth()+1;var yr=td.getFullYear();
    for(n=0;n<=10;n++){
        t+='<option value="' + mn + '"';
        if (mn == m) {
            t+=' selected="selected"';
        }
        t+='>' + months[mn-1] + ' ' + yr +'</option>';
        mn++; if (mn>12) { mn=1;yr++ }
    }
    t+= ' </select>&nbsp;';
    if (filaMonth == 10) {
        t+='&nbsp;&gt;&nbsp;';
    }
    else {
        t+='<a href="javascript:nextMonth('+y+','+m+');" title="' + tr.nextMonth +'">&nbsp;&gt;&nbsp;</a>';
    }
    t+='</td></tr>';
    t+='<tr class="b_calDayNames">';
    for(dn=0;dn<7;dn++){
        var cl = '';
        if ((dn%7==5) || (dn%7 == 6)) cl += ' b_calWeekend';
        t+='<th class="'+cl+'">'+days[dn]+'</th>';
    }
    t+='</tr><tr class="b_calDays">';
    for(i=1;i<=42;i++){
        var x = i - (firstMonthDay+6)%7;
        if (x > daysInMonth[m-1] || x <1) x = '&nbsp;';
        var cl = '';
        var href = 0;
        if ((i%7==0) || (i%7 == 6)) cl += ' b_calWeekend';
        if (x>0){
            var xDay = new Date(y, m-1, x);
            if ((xDay.getFullYear() == y) && (xDay.getMonth()+1 == m)
                && (xDay.getDate() == d))
                { cl += ' b_calSelected' ; href=1}
            if ((xDay.getFullYear() == td.getFullYear())
                && (xDay.getMonth() == td.getMonth())
                && (xDay.getDate() == td.getDate()))
                { cl += ' b_calToday'; href=1;}
            else {
                if (xDay > td){ cl += ' b_calFuture'; href=1; }
                else {
                    if (xDay < td) { cl += ' b_calPast'}
                }
            }
        };
        t+='<td class="'+cl+'">';
        if (href){
            t+='<a href="javascript:pickDate('+y+','+m+','+x+',\''+dt+'\',\''+frm+'\');">'+x+'</a>';
        } else {
            t+=x;
        }
        t+='</td>';
        if(((i)%7==0)&&(i<36)) {
            t+='</tr><tr class="b_calDays">';
        }
    }
    t+='</tr><tr class="b_calClose"><td colspan="7"><a href="javascript:closeCal();">' + tr.closeCalendar + '</a></td></tr></table>';
    document.getElementById("b_calendarInner").innerHTML= t;
}

function prevMonth(y,m) {
    if (new Date(y,m-1,1) < td) return;
    if (m > 1) {m--} else {m = 12; y--};
    buildCal(y,m);
}

function nextMonth(y,m) {
//    if ((new Date(y,m-1,1) - td) > 1000*3600*24*300) return;
    if (m<12){m++;} else {m=1;y++;}
    if (y > td.getFullYear() && m >= td.getMonth() ) return;
    buildCal(y,m);
}

function goMonth(m){
    var y = td.getFullYear();
    if (m < td.getMonth()+1) y++;
    buildCal(y,m);
}

function pickDate(y,m,d,dt,frm){
    // set form values
	var f = calendar.calf;
    var dt = calendar.caldt;
    f[dt + '_month'].value = y + "-"  + m;
    f[dt + '_day'].value = d;
	tickCheckBox('b_availcheck');
	if (dt == "b_checkin"){
		checkDateOrder(calendar.calfrm, 'b_checkin_day', 'b_checkin_month', 'b_checkout_day', 'b_checkout_month');
	}
    closeCal();
}

function checkDateOrder(frm, ci_day, ci_month_year, co_day, co_month_year) {
	if (document.getElementById) {
		var frm = document.getElementById(frm);
		// create date object from checkin values
		// set date to 12:00 to avoid problems with one
		// date being wintertime and the other summertime
		var my = frm[ci_month_year].value.split("-");
	    var ci = new Date (my[0], my[1]-1, frm[ci_day].value, 12, 0, 0, 0);

        // create date object from checkout values
	    my = frm[co_month_year].value.split("-");
	    var co = new Date (my[0], my[1]-1, frm[co_day].value, 12, 0, 0, 0);

		// if checkin date is at or after checkout date,
		// add a day full of milliseconds, and set the
		// selectbox values for checkout date to new value
	    if (ci >= co){
    	    co.setTime(ci.getTime() + 1000 * 60 * 60 * 24);
	        frm[co_day].value =  co.getDate();
    	    var com = co.getMonth()+1;
	        frm[co_month_year].value = co.getFullYear() + "-" + com;
    	}
	}
}