var till_noon=0.499999;
 
function isInt(value) {
    if (value == "") {
        return false;
    }
    for (var i = 0; i < value.length; i++) {
        if (value.charAt(i) < "0" || value.charAt(i) > "9") {
            return false;
        }
    }
    return true;
}

function pr_day( val, the_time )
{
  var cv = Math.floor(val); 
  if (cv==0)
     return "<u>vandaag " + the_time + " uur</u>";
  else if (cv==1)
     return "<u>morgen " +  the_time + " uur</u>";
  else if (cv==-1)
     return "<u>gisteren " + the_time + " uur</u>";
  else if (cv<0)
     return "<u>"+Math.abs(cv) + "</u> dagen geleden";
  else
     return "over <u>"+cv+"</u> dagen";
}

function moonPhase(phase)
  // convert moon phase percent to nice words
{
  if(phase >= 0 && phase < 0.033 )
    var phaseName = "nieuwe maan";
  else if(phase < 0.225)
    var phaseName = "wassende maan";
  else if(phase < 0.275)
    var phaseName = "eerste kwartier";
  else if(phase < 0.475)
    var phaseName = "wassende maan";
  else if(phase < 0.525)
    var phaseName = "volle maan";
  else if(phase < 0.735)
    var phaseName = "afnemende maan";
  else if(phase < 0.775)
    var phaseName = "laatste kwartier";
  else if(phase < 0.967)
    var phaseName = "afnemende maan";
  else if(phase < 1.0)
    var phaseName = "nieuwe maan";
  else 
    var phaseName ="????";
  return phaseName;
}

function print_sun_rise_set(rise, set )
{
  
  if (rise=="^^")
     document.write("gaat vandaag niet onder.\n");
  else if (rise=="vv")
     document.write("komt vandaag niet op.\n");
  else
  {
     if (rise=="..")
        document.write("komt vandaag niet op,");
     else
        document.write("komt op om "+rise+" uur,");
     if (set=="..")
        document.write(" en gaat vandaag niet onder");
     else
        document.write(" en gaat onder om "+set+" uur");
  }
}
document.write ('<font size=1 face="arial,helvetica,courier">');
document.write ('<a href="http://www.hetweer.nu/calendar_converter.html" target="_blank">datum</a>: 23 februari 2012\n');
document.write ('<br>temperatuur: <u>' + " 7.9" + '</u> <sup>o</sup>C in <a href="http://www.hetweer.nu" target="_blank">haaksbergen</a> (52.168N <sup>o</sup>NB, 6.726E <sup>o</sup>OL)'); 

// when "last_new_moon_julian_date to minutes" is an integer, all sun and moon info is assumed valid
if ( isInt( "2" ) )
{
  now_julian_date			= parseFloat("2455980.729168");
  last_new_moon_julian_date	= parseFloat("2455979.442467");
  new_moon_julian_date		= parseFloat("2456009.110747");
  full_moon_julian_date		= parseFloat("2455994.903967");
  var phName = moonPhase((now_julian_date-last_new_moon_julian_date)/(new_moon_julian_date-last_new_moon_julian_date));
  var daysTillFull = Math.floor(full_moon_julian_date+till_noon) - Math.floor(now_julian_date+till_noon);
  var daysTillNew  = Math.floor(new_moon_julian_date+till_noon)  - Math.floor(now_julian_date+till_noon);

  document.write ('<br>de <a href="http://www.hetweer.nu/sunrise_moonrise.html" target="_blank">zon</a> ');
  print_sun_rise_set( "07:33","18:00");
 
  document.write('<br><a href="http://www.hetweer.nu/sunrise_moonrise.html" target="_blank">maan</a>stand: <u>' + phName );
  document.write("</u>, nieuwe maan " + pr_day(daysTillNew, "15:39" ));
  document.write(", volle maan " + pr_day(daysTillFull,"10:41"));
}
else
{
  document.write("<br>op dit moment zijn de datum, nauwkeurige tijdweergave en gegevens van de zon en maan helaas niet beschikbaar");
  document.write("<br>binnen 1 uur is dit hersteld. het spijt me voor dit ongemak");
}
document.write ('</font>');