/*
Author: mg12
Update: 2008/05/05
Author URI: http://www.neoease.com/
*/
(function() {

function $(id) {
	return document.getElementById(id);
}

function setStyleDisplay(id, status) {
	$(id).style.display = status;
}

function goTop(a, t) {
	a = a || 0.1;
	t = t || 16;

	var x1 = 0;
	var y1 = 0;
	var x2 = 0;
	var y2 = 0;
	var x3 = 0;
	var y3 = 0;

	if (document.documentElement) {
		x1 = document.documentElement.scrollLeft || 0;
		y1 = document.documentElement.scrollTop || 0;
	}
	if (document.body) {
		x2 = document.body.scrollLeft || 0;
		y2 = document.body.scrollTop || 0;
	}
	var x3 = window.scrollX || 0;
	var y3 = window.scrollY || 0;

	var x = Math.max(x1, Math.max(x2, x3));
	var y = Math.max(y1, Math.max(y2, y3));

	var speed = 1 + a;
	window.scrollTo(Math.floor(x / speed), Math.floor(y / speed));
	if(x > 0 || y > 0) {
		var f = "MGJS.goTop(" + a + ", " + t + ")";
		window.setTimeout(f, t);
	}
}

function switchTab(showPanels, hidePanels, activeTab, activeClass, fadeTab, fadeClass) {
	$(activeTab).className = activeClass;
	$(fadeTab).className = fadeClass;

	var panel, panelList;
	panelList = showPanels.split(',');
	for (var i = 0; i < panelList.length; i++) {
		var panel = panelList[i];
		if ($(panel)) {
			setStyleDisplay(panel, 'block');
		}
	}
	panelList = hidePanels.split(',');
	for (var i = 0; i < panelList.length; i++) {
		panel = panelList[i];
		if ($(panel)) {
			setStyleDisplay(panel, 'none');
		}
	}
}

function loadCommentShortcut() {
	$('comment').onkeydown = function (moz_ev) {
		var ev = null;
		if (window.event){
			ev = window.event;
		} else {
			ev = moz_ev;
		}
		if (ev != null && ev.ctrlKey && ev.keyCode == 13) {
			$('submit').click();
		}
	}
	$('submit').value += ' (Ctrl+Enter)';
}

function getElementsByClassName(className, tag, parent) {
	parent = parent || document;

	var allTags = (tag == '*' && parent.all) ? parent.all : parent.getElementsByTagName(tag);
	var matchingElements = new Array();

	className = className.replace(/\-/g, '\\-');
	var regex = new RegExp('(^|\\s)' + className + '(\\s|$)');

	var element;
	for (var i = 0; i < allTags.length; i++) {
		element = allTags[i];
		if (regex.test(element.className)) {
			matchingElements.push(element);
		}
	}

	return matchingElements;
}

window['MGJS'] = {};
window['MGJS']['$'] = $;
window['MGJS']['setStyleDisplay'] = setStyleDisplay;
window['MGJS']['goTop'] = goTop;
window['MGJS']['switchTab'] = switchTab;
window['MGJS']['loadCommentShortcut'] = loadCommentShortcut;
window['MGJS']['getElementsByClassName'] = getElementsByClassName;

})();


/* Smooth scrolling
   Changes links that link to other parts of this page to scroll
   smoothly to those links rather than jump to them directly, which
   can be a little disorienting.

   sil, http://www.kryogenix.org/

   v1.0 2003-11-11
   v1.1 2005-06-16 wrap it up in an object
*/

var ss = {
  fixAllLinks: function() {
    // Get a list of all links in the page
    var allLinks = document.getElementsByTagName('a');
    // Walk through the list
    for (var i=0;i<allLinks.length;i++) {
      var lnk = allLinks[i];
      if ((lnk.href && lnk.href.indexOf('#') != -1) &&
          ( (lnk.pathname == location.pathname) ||
	    ('/'+lnk.pathname == location.pathname) ) &&
          (lnk.search == location.search)) {
        // If the link is internal to the page (begins in #)
        // then attach the smoothScroll function as an onclick
        // event handler
        ss.addEvent(lnk,'click',ss.smoothScroll);
      }
    }
  },

  smoothScroll: function(e) {
    // This is an event handler; get the clicked on element,
    // in a cross-browser fashion
    if (window.event) {
      target = window.event.srcElement;
    } else if (e) {
      target = e.target;
    } else return;

    // Make sure that the target is an element, not a text node
    // within an element
    if (target.nodeName.toLowerCase() != 'a') {
      target = target.parentNode;
    }

    // Paranoia; check this is an A tag
    if (target.nodeName.toLowerCase() != 'a') return;

    // Find the <a name> tag corresponding to this href
    // First strip off the hash (first character)
    anchor = target.hash.substr(1);
    // Now loop all A tags until we find one with that name
    var allLinks = document.getElementsByTagName('a');
    var destinationLink = null;
    for (var i=0;i<allLinks.length;i++) {
      var lnk = allLinks[i];
      if (lnk.name && (lnk.name == anchor)) {
        destinationLink = lnk;
        break;
      }
    }
    if (!destinationLink) destinationLink = document.getElementById(anchor);

    // If we didn't find a destination, give up and let the browser do
    // its thing
    if (!destinationLink) return true;

    // Find the destination's position
    var destx = destinationLink.offsetLeft;
    var desty = destinationLink.offsetTop;
    var thisNode = destinationLink;
    while (thisNode.offsetParent &&
          (thisNode.offsetParent != document.body)) {
      thisNode = thisNode.offsetParent;
      destx += thisNode.offsetLeft;
      desty += thisNode.offsetTop;
    }

    // Stop any current scrolling
    clearInterval(ss.INTERVAL);

    cypos = ss.getCurrentYPos();

    ss_stepsize = parseInt((desty-cypos)/ss.STEPS);
    ss.INTERVAL =
setInterval('ss.scrollWindow('+ss_stepsize+','+desty+',"'+anchor+'")',10);

    // And stop the actual click happening
    if (window.event) {
      window.event.cancelBubble = true;
      window.event.returnValue = false;
    }
    if (e && e.preventDefault && e.stopPropagation) {
      e.preventDefault();
      e.stopPropagation();
    }
  },

  scrollWindow: function(scramount,dest,anchor) {
    wascypos = ss.getCurrentYPos();
    isAbove = (wascypos < dest);
    window.scrollTo(0,wascypos + scramount);
    iscypos = ss.getCurrentYPos();
    isAboveNow = (iscypos < dest);
    if ((isAbove != isAboveNow) || (wascypos == iscypos)) {
      // if we've just scrolled past the destination, or
      // we haven't moved from the last scroll (i.e., we're at the
      // bottom of the page) then scroll exactly to the link
      window.scrollTo(0,dest);
      // cancel the repeating timer
      clearInterval(ss.INTERVAL);
      // and jump to the link directly so the URL's right
      location.hash = anchor;
    }
  },

  getCurrentYPos: function() {
    if (document.body && document.body.scrollTop)
      return document.body.scrollTop;
    if (document.documentElement && document.documentElement.scrollTop)
      return document.documentElement.scrollTop;
    if (window.pageYOffset)
      return window.pageYOffset;
    return 0;
  },

  addEvent: function(elm, evType, fn, useCapture) {
    // addEvent and removeEvent
    // cross-browser event handling for IE5+,  NS6 and Mozilla
    // By Scott Andrew
    if (elm.addEventListener){
      elm.addEventListener(evType, fn, useCapture);
      return true;
    } else if (elm.attachEvent){
      var r = elm.attachEvent("on"+evType, fn);
      return r;
    } else {
      alert("Handler could not be removed");
    }
  }
}

ss.STEPS = 10;

ss.addEvent(window,"load",ss.fixAllLinks);