// xHeight r6, Copyright 2001-2007 Michael Foster (Cross-Browser.com)
// Part of X, a Cross-Browser Javascript Library, Distributed under the terms of the GNU LGPL

function xHeight(e,h)
{
  if(!(e=xGetElementById(e))) return 0;
  if (xNum(h)) {
    if (h<0) h = 0;
    else h=Math.round(h);
  }
  else h=-1;
  var css=xDef(e.style);
  if (e == document || e.tagName.toLowerCase() == 'html' || e.tagName.toLowerCase() == 'body') {
    h = xClientHeight();
  }
  else if(css && xDef(e.offsetHeight) && xStr(e.style.height)) {
    if(h>=0) {
      var pt=0,pb=0,bt=0,bb=0;
      if (document.compatMode=='CSS1Compat') {
        var gcs = xGetComputedStyle;
        pt=gcs(e,'padding-top',1);
        if (pt !== null) {
          pb=gcs(e,'padding-bottom',1);
          bt=gcs(e,'border-top-width',1);
          bb=gcs(e,'border-bottom-width',1);
        }
        // Should we try this as a last resort?
        // At this point getComputedStyle and currentStyle do not exist.
        else if(xDef(e.offsetHeight,e.style.height)){
          e.style.height=h+'px';
          pt=e.offsetHeight-h;
        }
      }
      h-=(pt+pb+bt+bb);
      if(isNaN(h)||h<0) return;
      else e.style.height=h+'px';
    }
    h=e.offsetHeight;
  }
  else if(css && xDef(e.style.pixelHeight)) {
    if(h>=0) e.style.pixelHeight=h;
    h=e.style.pixelHeight;
  }
  return h;
}