function ss_fixAllLinks() {
 // 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',smoothScroll);
   }
 }
}

function smoothScroll(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.nodeType == 3) {
   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 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();
 }
}

function ss_scrollWindow(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;
 }
}

function ss_getCurrentYPos() {
 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;
}

function ss_addEvent(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;
 }
}  

var ss_INTERVAL;
var ss_STEPS = 25;

ss_addEvent(window,"load",ss_fixAllLinks);





// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 
// - - - - - - ( weather info sliding panels ) - - - - - - - - - - - - - - - - - - - -
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 
function primeSlide()
	{
	// set the class name of the containing div to hide appropriate html elements
	document.getElementById('weather-conditions').className = 'hide';
	
	// create html elements using js
	var make = createHTML();
	
	// set panel vars (just for neatness' sake)
	var infoPanel = document.getElementById('weatherinfo');
	var infoTrigger = document.getElementById('weatherinfo-trigger');
	var infoHide = document.getElementById('weatherinfo-hideme');
	var dorsetPanel = document.getElementById('dorset');
	var dorsetTrigger = document.getElementById('dorset-trigger');
	var dorsetHide = document.getElementById('dorset-hideme');
	var dorsetBack = document.getElementById('dorset-back');
	var sanfranPanel = document.getElementById('sanfrancisco');
	var sanfranTrigger = document.getElementById('sanfrancisco-trigger');
	var sanfranHide = document.getElementById('sanfrancisco-hideme');
	var sanfranBack = document.getElementById('sanfrancisco-back');
	
	// add in the panel state variables
	infoPanel.state = 'up';
	dorsetPanel.state = 'up';
	sanfranPanel.state = 'up';
	
	// set event listeners
	addEvent(infoTrigger, 'click', function(e){clearScreen(infoPanel)});
	addEvent(infoHide, 'click', function(e){clearScreen(infoPanel)});
	addEvent(dorsetTrigger, 'click', function(e){clearScreen(dorsetPanel)});
	addEvent(dorsetHide, 'click', function(e){clearScreen(dorsetPanel)});
	addEvent(dorsetBack, 'click', function(e){clearScreen(infoPanel)});
	addEvent(sanfranTrigger, 'click', function(e){clearScreen(sanfranPanel)});
	addEvent(sanfranHide, 'click', function(e){clearScreen(sanfranPanel)});
	addEvent(sanfranBack, 'click', function(e){clearScreen(infoPanel)});
	}

function clearScreen(thisPanel)
	{
	// set panel vars
	var infoPanel = document.getElementById('weatherinfo');
	var dorsetPanel = document.getElementById('dorset');
	var sanfranPanel = document.getElementById('sanfrancisco');
	// loop through and close any open windows that aren't this panel
	var panels = new Array(infoPanel, dorsetPanel, sanfranPanel);
	for (var i=0; i<panels.length; i++)
		{
		if (((panels[i].state == 'down') || (panels[i].state == 'downing')) && (panels[i] != thisPanel))
			{
			setSlide(panels[i]);
			}
		}
	// run for this panel
	setSlide(thisPanel);
	}

function setSlide(thisPanel)
	{	
	// grab the height (this is a number such as -500)
	thisPanel.height = thisPanel.offsetHeight;
	
	// if this panel is fully up
	if (thisPanel.state == 'up')
		{	
		// re-style the panel so it's only just out of site
		thisPanel.style.top = "-"+thisPanel.height+"px";
		
		// set number of frames the animation will take
		var numFrames = 12;
		}
	else
		{
		// calculate the number of frames the animation will take
		// (bearing in mind it could be halfway through an up or down movement)
		var finPos = thisPanel.height;
		var nowPos = thisPanel.style.top;
		nowPos = nowPos.substring(0, (nowPos.length - 2));
		var toGo = (finPos - nowPos);
		var numFrames = Math.round((12 / thisPanel.height) * toGo);
		numFrames = (numFrames == 0) ? 1 : numFrames;
		}
	
	// set y start position
	var yStart = thisPanel.offsetTop;
	// set y end position
	switch (thisPanel.state)
		{
		case 'up':
			thisPanel.state = 'downing';
			var yEnd = 0;
			break;
		case 'downing':
			thisPanel.state = 'uping';
			var yEnd = 0;
			break;
		case 'down':
			thisPanel.state = 'uping';
			var yEnd = "-"+thisPanel.height;
			break;
		case 'uping':
			thisPanel.state = 'downing';
			var yEnd = "-"+thisPanel.height;
			break;
		}
	
	// set current frame number
	frameNum = 0;
	// calculate y distance to be moved each frame
	var yDist = (yEnd - yStart)/(numFrames - 1);
	
	// run the sliding function
	runSlide(thisPanel, yStart, yDist, frameNum, numFrames);
	}

function runSlide(thisPanel, yStart, yDist, frameNum, numFrames)
	{
	// if the animation still has frames left to run
	if (frameNum < numFrames)
		{
		thisPanel.style.top = (yStart + yDist*frameNum) + "px";
		frameNum++;
		return setTimeout(function(){runSlide(thisPanel, yStart, yDist, frameNum, numFrames)}, 8);
		}
	// if the animation is complete
	else
		{
		// if it was moving down
		if (thisPanel.state == 'downing')
			{
			// set to all the way down
			thisPanel.state = 'down';
			}
		else
			{
			thisPanel.state = 'up';
			thisPanel.style.top = "-5000px";
			}
		}
	}

function createHTML()
	{
	// create weather info trigger elements
	var infoTrigger = document.createElement('div');
	infoTrigger.id = 'weatherinfo-trigger';
	infoTrigger.setAttribute('title', 'View extra information on the weather banner');
	document.body.appendChild(infoTrigger);
	
	// create weather info elements
	var infoPanel = document.createElement('div');
	infoPanel.id = 'weatherinfo';
	infoPanel.innerHTML = '<div class="border"><h3>Panorama information</h3><p>The image displayed above is a 1600 pixel-wide panoramic view from the top of my parents&#8217; house in Dorset, England. The system uses an XML weather feed from their local airbase to provide an up-to-the-minute graphical representation of the current weather, moon, and daylight conditions at their house. It\'s pretty cool, really.</p><p>You can <a href="/blog/colophon/#the-pano" title="View the panorama section in the colophon">read more about the panorama</a>, and how it was created, in the <a href="/blog/colophon/" title="View the colophon">Colophon</a>; or you can select an option from below and view detailed weather information for Dorset, or for San Francisco (where I currently live).</p><ul><li id="dorset-trigger" title="View the latest weather conditions at this location">View live weather information for Leigh, Dorset, UK.</li><li id="sanfrancisco-trigger" title="View the latest weather conditions at this location">View live weather information for San Francisco, California, USA.</li></ul><div id="weatherinfo-hideme" title="&#8593; Hide this panel">&#8593; Hide this panel</div></div>';
	document.getElementById('right').appendChild(infoPanel);
	
	// create dorset elements
	var dorsetPanel = document.getElementById('dorset');
	var dorsetHide = document.createElement('div');
	dorsetHide.id = 'dorset-hideme';
	dorsetHide.appendChild(document.createTextNode('\u2191 Hide this panel'));
	dorsetPanel.getElementsByTagName('div')[0].appendChild(dorsetHide);
	var dorsetBack = document.createElement('div');
	dorsetBack.id = 'dorset-back';
	dorsetBack.appendChild(document.createTextNode('\u2190 Go back to the info panel'));
	dorsetPanel.getElementsByTagName('div')[0].appendChild(dorsetBack);
	
	// create san francisco elements
	var sanfranPanel = document.getElementById('sanfrancisco');
	var sanfranHide = document.createElement('div');
	sanfranHide.id = 'sanfrancisco-hideme';
	sanfranHide.appendChild(document.createTextNode('\u2191 Hide this panel'));
	sanfranPanel.getElementsByTagName('div')[0].appendChild(sanfranHide);
	var sanfranBack = document.createElement('div');
	sanfranBack.id = 'sanfrancisco-back';	
	sanfranBack.appendChild(document.createTextNode('\u2190 Go back to the info panel'));
	sanfranPanel.getElementsByTagName('div')[0].appendChild(sanfranBack);
	return;
	}
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 

// run the onload script

function runScripts()
	{
	ss_fixAllLinks();
	primeSlide();
	}
window.onload = runScripts;