// detect browser
NS4 = (document.layers) ? 1 : 0;
IE4 = (document.all) ? 1 : 0;
// W3C stands for the W3C standard, implemented in Mozilla (and Netscape 6) and IE5
W3C = (document.getElementById) ? 1 : 0; 

function makeVisible ( name, hide ) {
 //alert (name);
 var ele;
  if ( W3C ) {
    ele = document.getElementById(name);
  } else if ( NS4 ) {
    ele = document.layers[name];
  } else { // IE4
    ele = document.all[name];
  }

  if ( NS4 ) {
    ele.visibility = "show";
  } else {  // IE4 & W3C & Mozilla
    ele.style.visibility = "visible";
    if ( hide )
     ele.style.display = "";
  }
}

function makeInvisible ( name, hide ) {
  //alert (name);
 if (W3C) {
    document.getElementById(name).style.visibility = "hidden";
    if ( hide )
      document.getElementById(name).style.display = "none";
  } else if (NS4) {
    document.layers[name].visibility = "hide";
  } else {
    document.all[name].style.visibility = "hidden";
    if ( hide )
      document.all[name].style.display = "none";
  }
}

function showTab (name) {
 if (! document.getElementById) { return true; }
 for (var i=0; i<tabs.length; i++) {
  var tname = tabs[i];
  var tab = document.getElementById("tab_" + tname);
  if (tab) {
   tab.className = (tname == name) ? "tabfor" : "tabbak";
  }
  var div = document.getElementById("tabscontent_" + tname);
  if (div) {
   div.style.display = (tname == name) ? "block" : "none";
  }
 }
 return false;
}

function visByClass(classname, state){
 var inc=0;
 var alltags=document.all? document.all : document.getElementsByTagName("*");
 for (i=0; i<alltags.length; i++){
 var str=alltags[i].className;
   if ( str && str.match(classname) )
     if ( state=='hide')
       alltags[i].style.display = "none";
     else
       alltags[i].style.display = "";     
 }
} 
//these common function is placed here because all the files that use it 
//also use visibility functions
function selectDate (  day, month, year, current, evt, form ) {
  // get currently selected day/month/year
  monthobj = eval ( 'document.' + form.name + '.' + month );
  curmonth = monthobj.options[monthobj.selectedIndex].value;
  yearobj = eval ( 'document.' + form.name + '.' + year );
  curyear = yearobj.options[yearobj.selectedIndex].value;
  date = curyear;

    if (document.getElementById) {
    mX = evt.clientX   + 40;
    mY = evt.clientY  + 120;
  }
  else {
    mX = evt.pageX + 40;
    mY = evt.pageY +130;
  }
  var MyPosition = 'scrollbars=no,toolbar=no,left=' + mX + ',top=' + mY + ',screenx=' + mX + ',screeny=' + mY ;
  if ( curmonth < 10 )
    date += "0";
  date += curmonth;
  date += "01";
  url = "datesel.php?form=" + form.name + "&fday=" + day +
    "&fmonth=" + month + "&fyear=" + year + "&date=" + date;
  var colorWindow = window.open(url,"DateSelection","width=300,height=180,"  + MyPosition);
}

function selectColor ( color, evt ) {
  url = "colors.php?color=" + color;
  if (document.getElementById) {
    mX = evt.clientX   + 40;
  }
  else {
    mX = evt.pageX + 40;
  }
  var mY = 100;
  var MyOptions = 'width=390,height=365,scrollbars=0,left=' + mX + ',top=' + mY + ',screenx=' + mX + ',screeny=' + mY;
  var colorWindow = window.open(url,"ColorSelection","width=390,height=365," + MyOptions );
}

function valid_color ( str ) {
 var validColor = /^#[0-9a-fA-F]{3}$|^#[0-9a-fA-F]{6}$/;

 return validColor.test ( str );
}

// Updates the background-color of a table cell
// Parameters:
//    input - element containing the new color value
//    target - id of sample
function updateColor ( input, target ) {
 // The cell to be updated
 var colorCell = document.getElementById(target);
 // The new color
 var color = input.value;

 if (!valid_color ( color ) ) {
   // Color specified is invalid; use black instead
  colorCell.style.backgroundColor = "#000000";
  input.select();
  input.focus();
  alert ( 'Invalid Color');
 } else {
  colorCell.style.backgroundColor = color;
 }
}

function toggle_datefields( name, ele ) {
  var enabled = document.getElementById(ele.id).checked;
  if ( enabled ) { 
      makeInvisible ( name );
  } else {
      makeVisible ( name ); 
  }
}

function callEdit() {
  var features = 'width=600,height=500,resizable=yes,scrollbars=no';
  var url = "edit_entry.php";
  editwin = window.open( url, "edit_entry", features ); 
}