/**   
*common.js -- personal homepages common javascripts
*
*	Javascript File
*
*       @Author:      Ian Robertson iroberts@narian.org.uk (http://narian.org.uk)
*
*       @License:     GPL (see http://www.gnu.org/licenses/gpl.txt)
*
*       @Created:     21-Sep-2005 for narian
*
*       @svnid:    $Id$
*
*-----------------------------------------------------------------------------
*
*	Description:
*
*-----------------------------------------------------------------------------
*
*	TODO:
*
*-----------------------------------------------------------------------------
*/


/**
* function IE_hover_fix
*
*	Purpose: add :hover effect to selectors in IE 6 and previous
*
*	@global document 
*
*	@param parent_id        id of containing element 
*	@param node_type        type to be hovered ( in CAPS ) eg LI, DIV, ... 
*       @param class_name       class to activate / deactivate on hover
*
*	@return NONE
*
*	Notes:
*               called @ window.onload
*
*       parametarised see http://www.htmldog.com/articles/suckerfish/dropdowns/
*       for original.
*
*       user agent checked as IE 7+ probably has no need for this
*
*
*/
function IE_hover_fix( parent_id, node_type, class_name ) {

  if( navigator.userAgent.search(/MSIE.[5-6]/i ) > 0 ){ 
    var sfEls = document.getElementById(parent_id).getElementsByTagName(node_type);
    for (var i=0; i<sfEls.length; i++) {
      sfEls[i].onmouseover=function() {
        this.className+=" "+class_name;
      }
      sfEls[i].onmouseout=function() {
        this.className=this.className.replace(new RegExp(" "+class_name+"\\b"), "");
      }
    }
  }
} // END function IE_hover_fix



/*      from http://pro.html.it/esempio/nifty/ 1-Sep-05 */
var isXHTML;
function NiftyCheck(){
if(!document.getElementById || !document.createElement)
    return(false);
isXHTML=/html\:/.test(document.getElementsByTagName('body')[0].nodeName);
if(Array.prototype.push==null){Array.prototype.push=function(){
      this[this.length]=arguments[0]; return(this.length);}}
return(true);
}

function Rounded(selector,wich,bk,color,opt){
var i,prefixt,prefixb,cn="r",ecolor="",edges=false,eclass="",b=false,t=false;

if(color=="transparent"){
    cn=cn+"x";
    ecolor=bk;
    bk="transparent";
    }
else if(opt && opt.indexOf("border")>=0){
    var optar=opt.split(" ");
    for(i=0;i<optar.length;i++)
        if(optar[i].indexOf("#")>=0) ecolor=optar[i];
    if(ecolor=="") ecolor="#666";
    cn+="e";
    edges=true;
    }
else if(opt && opt.indexOf("smooth")>=0){
    cn+="a";
    ecolor=Mix(bk,color);
    }
if(opt && opt.indexOf("small")>=0) cn+="s";
prefixt=cn;
prefixb=cn;
if(wich.indexOf("all")>=0){t=true;b=true}
else if(wich.indexOf("top")>=0) t="true";
else if(wich.indexOf("tl")>=0){
    t="true";
    if(wich.indexOf("tr")<0) prefixt+="l";
    }
else if(wich.indexOf("tr")>=0){
    t="true";
    prefixt+="r";
    }
if(wich.indexOf("bottom")>=0) b=true;
else if(wich.indexOf("bl")>=0){
    b="true";
    if(wich.indexOf("br")<0) prefixb+="l";
    }
else if(wich.indexOf("br")>=0){
    b="true";
    prefixb+="r";
    }
var v=getElementsBySelector(selector);
var l=v.length;
for(i=0;i<l;i++){
    if(edges) AddBorder(v[i],ecolor);
    if(t) AddTop(v[i],bk,color,ecolor,prefixt);
    if(b) AddBottom(v[i],bk,color,ecolor,prefixb);
    }
}

function AddBorder(el,bc){
var i;
if(!el.passed){
    if(el.childNodes.length==1 && el.childNodes[0].nodeType==3){
        var t=el.firstChild.nodeValue;
        el.removeChild(el.lastChild);
        var d=CreateEl("span");
        d.style.display="block";
        d.appendChild(document.createTextNode(t));
        el.appendChild(d);
        }
    for(i=0;i<el.childNodes.length;i++){
        if(el.childNodes[i].nodeType==1){
            el.childNodes[i].style.borderLeft="1px solid "+bc;
            el.childNodes[i].style.borderRight="1px solid "+bc;
            }
        }
    }
el.passed=true;
}
    
function AddTop(el,bk,color,bc,cn){
var i,lim=4,d=CreateEl("b");

if(cn.indexOf("s")>=0) lim=2;
if(bc) d.className="artop";
else d.className="rtop";
d.style.backgroundColor=bk;
for(i=1;i<=lim;i++){
    var x=CreateEl("b");
    x.className=cn + i;
    x.style.backgroundColor=color;
    if(bc) x.style.borderColor=bc;
    d.appendChild(x);
    }
el.style.paddingTop=0;
el.insertBefore(d,el.firstChild);
}

function AddBottom(el,bk,color,bc,cn){
var i,lim=4,d=CreateEl("b");

if(cn.indexOf("s")>=0) lim=2;
if(bc) d.className="artop";
else d.className="rtop";
d.style.backgroundColor=bk;
for(i=lim;i>0;i--){
    var x=CreateEl("b");
    x.className=cn + i;
    x.style.backgroundColor=color;
    if(bc) x.style.borderColor=bc;
    d.appendChild(x);
    }
el.style.paddingBottom=0;
el.appendChild(d);
}

function CreateEl(x){
if(isXHTML) return(document.createElementNS('http://www.w3.org/1999/xhtml',x));
else return(document.createElement(x));
}

function getElementsBySelector(selector){
var i,selid="",selclass="",tag=selector,f,s=[],objlist=[];

if(selector.indexOf(" ")>0){  //descendant selector like "tag#id tag"
    s=selector.split(" ");
    var fs=s[0].split("#");
    if(fs.length==1) return(objlist);
    f=document.getElementById(fs[1]);
    if(f) return(f.getElementsByTagName(s[1]));
    return(objlist);
    }
if(selector.indexOf("#")>0){ //id selector like "tag#id"
    s=selector.split("#");
    tag=s[0];
    selid=s[1];
    }
if(selid!=""){
    f=document.getElementById(selid);
    if(f) objlist.push(f);
    return(objlist);
    }
if(selector.indexOf(".")>0){  //class selector like "tag.class"
    s=selector.split(".");
    tag=s[0];
    selclass=s[1];
    }
var v=document.getElementsByTagName(tag);  // tag selector like "tag"
if(selclass=="")
    return(v);
for(i=0;i<v.length;i++){
    if(v[i].className.indexOf(selclass)>=0){
        objlist.push(v[i]);
        }
    }
return(objlist);
}

function Mix(c1,c2){
var i,step1,step2,x,y,r=new Array(3);
if(c1.length==4)step1=1;
else step1=2;
if(c2.length==4) step2=1;
else step2=2;
for(i=0;i<3;i++){
    x=parseInt(c1.substr(1+step1*i,step1),16);
    if(step1==1) x=16*x+x;
    y=parseInt(c2.substr(1+step2*i,step2),16);
    if(step2==1) y=16*y+y;
    r[i]=Math.floor((x*50+y*50)/100);
    }
return("#"+r[0].toString(16)+r[1].toString(16)+r[2].toString(16));
} 
/**
* function shadow_box
*
*	Purpose: add inner html to elements to create a drop shadow
*       effect.
*
*	@global document 
*
*	@param parent_type      type of parent containing element 
*	@param child_type       type of child containing element 
*       @param  selector        class of parent container being shadowed
*
*	@return NONE
*
*	Notes:
*               called @ window.onload
*
*       Inspired by http://www.mindsack.com/uxe/shadows/
*       Removed constant parameters -
*       ie class to start shadowing is now always "shadow"
*       document now used directly not passed as parameter
*
*       added exact check on class name rather than simply if
*       class name somewhere in class names string
*
*       Requires decor css ShadowBox
*
*       Used where there is html like 
*       <ul class="shadow">
*               <li>xxxx</li>
*       </ul>
*
*       Or
*
*       <div class="shadow">
*               <div  class="shadow_inner">
*               </div>
*       </div>
*       default css set for div example
*
*/
function shadow_box(parent_type, child_type, selector ) {
  var d = document;
  
  var lists = d.getElementsByTagName(parent_type);
  for (var i =  lists.length-1; i >=0; i--)
  {
    if (lists[i].className.indexOf(selector) != -1)
    {
      /**
      * should be able to do this with regex and match but
      * cannot see how to get js var into regex !
      */
      classes = lists[i].className.split( /\s/g );
      for ( var z = classes.length-1; z >=0 ; z-- ){
        if( classes[z] == selector ){ 
          for (var j =  lists[i].childNodes.length-1; j >=0; j--)
          {
            if (lists[i].childNodes[j].tagName == child_type.toUpperCase())
            {
              var shadow = d.createElement(child_type);
              shadow.className = 's';
              var content = d.createElement('div');
              content.className = 'c';
              content.innerHTML = lists[i].childNodes[j].innerHTML;
              lists[i].replaceChild(shadow, lists[i].childNodes[j]);
              shadow.appendChild(content);
            }
          }
        }
      }
    }
  }
} // end shadow_box 

/**
* function set_target_blank
*
*	Purpose: Provide target="_blank" to xhtml_docs via the rel attribute
*               of a link being set to "external"
*
*	@global  document
*
*	@param  NONE
*
*	@return NONE
*
*	Notes:
*               called @ window.onload; 
*
*/
function set_target_blank() {

  if (!document.getElementsByTagName ) return;
  
  var anchors = document.getElementsByTagName("a");

  for (var i=0; i<anchors.length; i++) {
    var anchor = anchors[i];
    if (anchor.getAttribute("href") && anchor.getAttribute("rel") == "external")
       anchor.target = "_blank";
  }
    
} // END function set_target_blank