var count=0;

function next(maxpage){ 

 if(document.getElementById("previous").disabled){
    document.getElementById("previous").disabled=false;
   
  };
  if(count < maxpage-1){
  
    var current="page"+count; 
    document.getElementById(current).style.display="none";
    count++;
    var next="page"+count;
    document.getElementById("multipage").style.visibility="hidden";
    document.getElementById(next).style.display="";
    document.getElementById("multipage").style.visibility="visible";

    
  }
  else{
    document.getElementById("next").disabled=true;
    
  }

}


function previous(){
  if(document.getElementById("next").disabled){
    document.getElementById("next").disabled=false;
    
  };
  if(count > 0){
    var label="page"+count;
    document.getElementById(label).style.display="none";
    count=count-1;
    var label="page"+count;
    document.getElementById("multipage").style.visibility="hidden";
    document.getElementById(label).style.display="";
    document.getElementById("multipage").style.visibility="visible";
  }
  else{
    document.getElementById("previous").disabled=true;
    
  }
}

function front(maxpage){

/* This function determines the height of the fieldset surrounding any table
   of listings.  For more than one page, we need to do
   some work to keep the height of the fieldset the same.  */
   

   document.getElementById("page0").style.display="";
   var multipageheight=document.getElementById("page0").offsetHeight;
  
   for(i=1; i<maxpage; i++){
     var pagetag="page"+i;
     document.getElementById(pagetag).style.display="";
     multipageheight=
     Math.max(multipageheight,document.getElementById(pagetag).offsetHeight);
     document.getElementById(pagetag).style.display="none";
        
   };
      
   multipageheight=multipageheight + 
                      3*document.getElementById("navigation").offsetHeight;
      
   document.getElementById("multipage").style.height=multipageheight+"px";
     

   count=0;
   document.getElementById("next").disabled=false;
   document.getElementById("previous").disabled=false;
  
}

function picture() {
   
   document.getElementById("padding").style.width=0+"px";
   document.getElementById("singlepage").getElementsByTagName("table")[0].className=
   "with-image";
      
   document.getElementById("picturebar").getElementsByTagName("img")[0].style.height=
   .8*document.getElementById("singlepage").getElementsByTagName("table")[0].offsetHeight+"px";
  
   document.getElementById("padding").style.width=
   document.getElementById("picturebar").getElementsByTagName("img")[0].offsetWidth
   -.16*document.getElementById("singlepage").offsetWidth+"px";
   
 
   document.getElementById("singlepage").style.display="none";
   document.getElementById("singlepage").style.display="";
  
}   

   

function seenornot(flip){

  if( flip > 0){ 
    document.getElementById("nobutton").checked=false;
    document.getElementById("yesbutton").checked=true
  }
  else{
    document.getElementById("nobutton").checked=true;
    document.getElementById("yesbutton").checked=false
  }
   
}

function validate(){
   
  if(!document.getElementById("entry").author.value.match(/^\w+.*,.*$/)){
    alert("Please enter Author");
    return false;
  };
  if(!document.getElementById("entry").year.value.match(/^\d\d\d\d$/)){
    alert("Please enter valid Year of Publication (yyyy)");
    return false;
  };
  if(!document.getElementById("entry").avtrtag.disabled &&
     !document.getElementById("entry").avtrtag.value.match(/\d\d\d\d$/)){
    alert("Please enter valid Avatar Tag (NAMEyyyy)");
    return false; 
  };
  return true;
}

function addfield(){
 
  if( document.getElementById("entry").keywords.value == ""){ 
    document.getElementById("entry").keywords.value=
    document.getElementById("entry").field.value+
    document.getElementById("entry").keywords.value
  }
  else{
    document.getElementById("entry").keywords.value=
    document.getElementById("entry").keywords.value+
    "; "+
    document.getElementById("entry").field.value
  }
}

function selectframe(a,b,c,d){

   parent.document.getElementsByTagName("frameset")[0].rows=a+"%,"+b+"%,"+c+"%,"+d+"%,10%";

}