// JavaScript Document

// Menu

function menu (id) {
	for (i = 1; i <= 4; i++) {
		if (i != id) {
			if (x = document.getElementById("sub" +i).style) {
				x.display = "none";
			}
		}
	}
	if (d = document.getElementById("sub" +id).style) {
		if (d.display == "") {
			d.display = "none";
		}
		if (d.display == "block") {
			d.display = "none";
		} else {
			d.display = "block";
		}
	}
	return false;
}


// Course form validation

function validateCourse(){
	err = 0
	msg = "";
	
	if(document.form1.venue.value == ""){
		msg += "Please select a venue\n";
		err = 1
	}
	if(document.form1.strName.value == ""){
		msg += "Please enter a your name\n";
		err = 1
	}
	if(document.form1.strAddress.value == ""){
		msg += "Please enter a your address\n";
		err = 1
	}
	if(document.form1.strTown.value == ""){
		msg += "Please enter a your Town\n";
		err = 1
	}
	if(document.form1.strPostcode.value == ""){
		msg += "Please enter a your Postcode\n";
		err = 1
	}
	if(document.form1.strPhoneNum.value == ""){
		msg += "Please enter a your Phone Number\n";
		err = 1
	}
	 if(document.form1.strEmail.value == ""){
		msg += "Please enter a your Email\n";
		err = 1
	}  
	if (err == 1){
		alert(msg);
		return false;
	}else{
		return true;
	}
}


// Pop-ups

function fnOpen(sHtml, nHeight) {
	var nWidth = 550;
	var nHeight = nHeight==undefined ? 640 : nHeight;
	var nLeftPos = (screen.width) ? (screen.width/2)-(nWidth/2) : 0;
	var nTopPos = (screen.height) ? (screen.height-nHeight)/2 : 0;
	var sFeatures = "width="+nWidth+", height="+nHeight+", left="+nLeftPos+", top="+nTopPos+", status=0, location=0, scrollbars=yes";
	newwindow = window.open(sHtml,"pop",sFeatures);
	if (window.focus) {newwindow.focus()}
	return false;
}



// Random banner images

var theImages = new Array()

theImages[0] = '/images/bannerImages/barge.jpg'
theImages[1] = '/images/bannerImages/canal.jpg'
theImages[2] = '/images/bannerImages/cruiser.jpg'
theImages[3] = '/images/bannerImages/team.jpg'


var j = 0
var p = theImages.length;
var preBuffer = new Array()
for (i = 0; i < p; i++){
   preBuffer[i] = new Image()
   preBuffer[i].src = theImages[i]
}
var whichImage = Math.round(Math.random()*(p-1));
function showImage(){
document.write('<img src="'+theImages[whichImage]+'">');
}