// 3 functions below from: http://www.brainerror.net/scripts_js_blendtrans.php
function opacity(opacStart, opacEnd, millisec) {
	//speed for each frame
	var speed = Math.round(millisec / 100);
	var timer = 0;

	//determine the direction for the blending, if start and end are the same nothing happens
	if(opacStart > opacEnd) {
		for(i = opacStart; i >= opacEnd; i--) {
			setTimeout("changeOpac(" + i + ")",(timer * speed));
			timer++;
		}
	} else if(opacStart < opacEnd) {
		for(i = opacStart; i <= opacEnd; i++)
			{
			setTimeout("changeOpac(" + i + ")",(timer * speed));
			timer++;
		}
	}
}

//change the opacity for different browsers
function changeOpac(opacity) {
	var img = bannerGetElement();
	var s = img.style;
	s.opacity = (opacity / 100);
	s.MozOpacity = (opacity / 100);
	s.KhtmlOpacity = (opacity / 100);
	s.filter = "alpha(opacity=" + opacity + ")";
}

function shiftOpacity(e, millisec) {
	//if an element is invisible, make it visible, else make it ivisible
	if(e.style.opacity == 0) {
		opacity(0, 100, millisec);
	} else {
		opacity(100, 0, millisec);
	}
}





var banners = [
	{'name' : '3M.gif'	, 'img' : new Image()	},
	{'name' : 'Aloevera.png'	, 'img' : new Image()	},
	{'name' : 'American Sports.gif'	, 'img' : new Image()	},
	{'name' : 'Bach.gif'	, 'img' : new Image()	},
	{'name' : 'Bloem.gif'	, 'img' : new Image()	},
	{'name' : 'Bonusan.gif'	, 'img' : new Image()	},
	{'name' : 'Facetrex.png'	, 'img' : new Image()	},
	{'name' : 'Heel.gif'	, 'img' : new Image()	},
	{'name' : 'ItalChile.png'	, 'img' : new Image()	},
	{'name' : 'Lavera.gif'	, 'img' : new Image()	},
	{'name' : 'Orthica.png'	, 'img' : new Image()	},
	{'name' : 'Ortholon.gif'	, 'img' : new Image()	},
	{'name' : 'VSM.png'	, 'img' : new Image()	},
	{'name' : 'Volatile.gif'	, 'img' : new Image()	},
	{'name' : 'Zarqa.png'	, 'img' : new Image()	},
	{'name' : 'Zonnatura.png'	, 'img' : new Image()	},
	{'name' : 'snakes.gif'	, 'img' : new Image()	}];
var banner_idx = Math.round(Math.random() * (banners.length - 1));

function bannerGetElement() {
	return document.getElementById('banner');
}

function bannerHide() {
	shiftOpacity(bannerGetElement(), 1000);
	if (++banner_idx >= banners.length) {
		banner_idx = 0;
	}
	setTimeout('bannerShow()', 1500);
}

function bannerShow() {
	if (!banners[banner_idx].img.src) {
		banners[banner_idx].img.src = '/img/banners/' + escape(banners[banner_idx].name);
	}
	if (banners[banner_idx].img.complete) {
		var img = bannerGetElement();
		img.src = banners[banner_idx].img.src;
		img.width = banners[banner_idx].img.width;
		img.height = banners[banner_idx].img.height;
		shiftOpacity(img, 1000);
		setTimeout('bannerHide()', 4000);
	}
	else {
		setTimeout('bannerShow()', 500);
	}
}

function bannersInit() {
	var img = bannerGetElement();
	if (!img) {
		return;
	}
	var s = img.style;
	s.opacity = 0;
	s.MozOpacity = 0;
	s.KhtmlOpacity = 0;
	s.filter = 'alpha(opacity=0)';
	setTimeout('bannerShow()', 1000);
}

xAddEventListener(this, 'load', function() { bannersInit(); },	false);