/* javascript for thomasrobertsphotography.com */

/*** navigation ***/

sfHover = function() {
	var sfEls = document.getElementById("nav").getElementsByTagName("LI");
	for (var i=0; i<sfEls.length; i++) {
		sfEls[i].onmouseover=function() {
			this.className+=" sfhover";
		}
		sfEls[i].onmouseout=function() {
			this.className=this.className.replace(new RegExp(" sfhover\\b"), "");
		}
	}
}
if (window.attachEvent) window.attachEvent("onload", sfHover);

/*** contact form ***/

function MM_findObj(n, d) { //v4.01
  var p,i,x;  if(!d) d=document; if((p=n.indexOf("?"))>0&&parent.frames.length) {
    d=parent.frames[n.substring(p+1)].document; n=n.substring(0,p);}
  if(!(x=d[n])&&d.all) x=d.all[n]; for (i=0;!x&&i<d.forms.length;i++) x=d.forms[i][n];
  for(i=0;!x&&d.layers&&i<d.layers.length;i++) x=MM_findObj(n,d.layers[i].document);
  if(!x && d.getElementById) x=d.getElementById(n); return x;
}

function MM_validateForm() { //v4.0
  var i,p,q,nm,test,num,min,max,errors='',args=MM_validateForm.arguments;
  for (i=0; i<(args.length-2); i+=3) { test=args[i+2]; val=MM_findObj(args[i]);
    if (val) { nm=val.name; if ((val=val.value)!="") {
      if (test.indexOf('isEmail')!=-1) { p=val.indexOf('@');
        if (p<1 || p==(val.length-1)) errors+='- '+nm+' must contain an e-mail address.\n';
      } else if (test!='R') { num = parseFloat(val);
        if (isNaN(val)) errors+='- '+nm+' must contain a number.\n';
        if (test.indexOf('inRange') != -1) { p=test.indexOf(':');
          min=test.substring(8,p); max=test.substring(p+1);
          if (num<min || max<num) errors+='- '+nm+' must contain a number between '+min+' and '+max+'.\n';
    } } } else if (test.charAt(0) == 'R') errors += '- '+nm+' is required.\n'; }
  } if (errors) alert('The following error(s) occurred:\n'+errors);
  document.MM_returnValue = (errors == '');
}



/* event_attach() takes care of attaching event handlers (functions) to events. 
 * this simplifies the process of attaching multiple handlers to a single event
 *
 * NOTE: the onload stack is executed in a LIFO manner to mimic 
 *       IE's window.attachEvent function. However, Opera also has its own
 *       window.attachEvent function which executes the onload stack in a 
 *       FIFO manner. FIFO is better, but IE has a larger user base, so
 *       LIFO is the way we go.
 */
function event_attach( event , func )
{
	if ( window.attachEvent )
	{
		window.attachEvent( event , func );
	}
	else
	{
		if ( ( typeof( func ) ).toLowerCase() != 'function' )
		{
			return;
		}
		if ( ( typeof( document.event_handlers ) ).toLowerCase() == 'undefined' )
		{
			document.event_handlers = new Array();
		}
		if ( ( typeof( document.event_handlers[ event ] ) ).toLowerCase() == 'undefined' )
		{
			document.event_handlers[ event ] = new Array();
		}
		if ( ( typeof( eval( 'window.' + event ) ) ).toLowerCase() != 'function' )
		{
			eval( 'window.' + event + ' = function () { if ( ( typeof( document.event_handlers[ \'' + event + '\' ] ) ).toLowerCase() != \'undefined\' ) { for ( i = document.event_handlers[ \'' + event + '\' ].length - 1 ; i >= 0  ; i-- ) { document.event_handlers[ \'' + event + '\' ][ i ](); } } } ' );
		}
		document.event_handlers[ event ][ document.event_handlers[ event ].length ] = func;
	}
}

/* Cookie API  v1.0.1
 * documentation: http://www.dithered.com/javascript/cookies/index.html
 * license: http://creativecommons.org/licenses/by/1.0/
 * code (mostly) by Chris Nott (chris[at]dithered[dot]com)
 */
function setCookie( name, value, expires, path, domain, secure )
{
	 var curCookie = name + "=" + escape(value) +
		((expires) ? "; expires=" + expires.toGMTString() : "") +
		((path) ? "; path=" + path : "") +
		((domain) ? "; domain=" + domain : "") +
		((secure) ? "; secure" : "");
	document.cookie = curCookie;
}
function getCookie( name )
{
	var dc = document.cookie;
	var prefix = name + "=";
	var begin = dc.indexOf( "; " + prefix );
	if ( begin == -1 )
	{
		begin = dc.indexOf(prefix);
		if (begin != 0) return null;
	}
	else
	{
		begin += 2;
	}
	var end = document.cookie.indexOf( ";", begin );
	if ( end == -1 )
	{
		end = dc.length;
	}
	return unescape(dc.substring(begin + prefix.length, end));
}
function deleteCookie( name, path, domain )
{
	var value = getCookie( name );
	if ( value != null )
	{
		document.cookie = name + "=" + 
			((path) ? "; path=" + path : "") +
			((domain) ? "; domain=" + domain : "") +
			"; expires=Thu, 01-Jan-70 00:00:01 GMT";
	}
	return value;
}

/* font size functions operate on the body element's
 * style and defines sizes in percentages. because
 * the default font size is set to 0 in the array,
 * the first value in the font_sizes array should
 * _ALWAYS_ be 100.
 *
 *	var font_sizes = new Array( 100, 110, 120 );
 *	var current_font_size = 0;
 *	event_attach( 'onload' , loadFontSize );
 */
function loadFontSize()
{
	current_font_size = parseInt( '0' + getCookie ( "font_size" ) );
	setFontSize ( current_font_size );
}
function setFontSize( size )
{
	if( size >= 0 && size < font_sizes.length )
	{
		current_font_size = size;
	}
	else if( ++current_font_size >= font_sizes.length )
	{
		current_font_size = 0;
	}
	if ( document.body )
	{
		document.body.style.fontSize = font_sizes[ current_font_size ] + '%';
		setCookie( "font_size" , current_font_size );
	}
}

/* standard trim function to remove leading and trailing 
 * whitespace from a given string
 */
function trim( str )
{
   return str.replace(/^\s*|\s*$/g,"");
}

/* stylesheets should be defined in the HTML via a LINK tag
 * and rel attribute set to "alternate stylesheet". the title
 * attribute is then set in the format of "title : group"
 * this function will disable all but the stylesheet specified
 * by title in the group specified by group.
 *
 * Based on code by Paul Sowden
 * http://www.alistapart.com/articles/alternate/
 *        
 */
function setActiveStyleSheet( title , group )
{
	var i, a, b, g, t;
	if ( !title || !group )
	{
		return;
	}
	for ( i = 0; ( a = document.getElementsByTagName( "link" )[ i ] ); i++ ) 
	{
		if ( a.getAttribute( "rel" ).indexOf( "style" ) != -1 && a.getAttribute( "title" ) )
		{
			b = ( a.getAttribute( "title" ) ).split( ":" );
			g = trim( b[ b.length - 1 ] );
			if ( g.toLowerCase() == group.toLowerCase() )
			{
				a.disabled = true;
				t = trim( ( a.getAttribute( "title" ) ).substring( 0, a.getAttribute( "title" ).length - b[ b.length - 1 ].length - 1 ) );
				if( t.toLowerCase() == title.toLowerCase() )
				{
					a.disabled = false;
				}
			}
			setCookie( "style_" + g.toLowerCase() , title );
		}
	}
}
function getPreferredStylesheet ( group )
{
	return ( getCookie ( "style_" + group ) );
}