/**
* JavaScript library containing general functions for the website.
*
* @author Anthon Matteman
* @dependencies none
*/
/** String constant for quotes. */
var QUOTE = "'";
/** Array containing the names of the days of the week. */
var DAY_ARRAY = new ArrayObject("Sunday", "Monday", "Tuesday", "Wednesday", "Thursday",
"Friday", "Saturday");
/** Array containing the names of the months of the year. */
var MONTH_ARRAY = new ArrayObject("January", "February", "March", "April", "May", "June",
"July", "August", "September", "October", "November",
"December");
/** Array containing the available slideshows. */
var SLIDESHOW_ARRAY = new ArrayObject(
new Slideshow("tol_indx.html", "Tour of London"),
new Slideshow("too_indx.html", "Tour of Oxford")
);
/** Indicates if this library is loaded in the HTML. */
var idxLibLoaded = true;
/** Variable for scrolling text. Is defined global to prevent errors with quotes. */
var scrollText = "";
/*
##################################################################################
# #
# UTILITY FUNCTIONS #
# #
##################################################################################
*/
/**
* Returns whether the current page is in a frame.
*
* @return boolean True if the page is in a frame
*/
function isPageInFrame() {
return (0 != parent.frames.length);
}
/**
* Constructs a new ArrayObject.
*/
function ArrayObject() {
this.length = ArrayObject.arguments.length;
for (var i = 0; i < this.length; i++) {
this[i] = ArrayObject.arguments[i];
}
this.add = addToArray;
}
/**
* Adds an object to an ArrayObject.
*
* @param object The object to add
*/
function addToArray(object) {
this.length = this.length + 1;
this[this.length - 1] = object;
}
/**
* Returns whether the browser is capable of image flips.
*
* @return boolean True if the browser can handle image flips
*/
function isBrowserRollCapable() {
var roll = true;
var browserName = navigator.appName;
var browserVersion = parseFloat(navigator.appVersion);
if ("Netscape" == browserName && 3.0 <= browserVersion) {
roll = true;
} else if ("Microsoft Internet Explorer" == browserName
&& 4.0 <= browserVersion) {
roll = true;
} else {
roll = false;
}
return roll;
}
/**
* Returns whether the browser is Internet Explorer 3.0.
*
* This function is especially useful to check if
* document.write in a library is supported.
*
* @return boolean True if the browser is IE 3.0
*/
function isBrowserIE30() {
var result = false;
if (-1 != navigator.userAgent.indexOf("MSIE 3.0;")) {
result = true;
}
return result;
}
/*
##################################################################################
# #
# FUNCTION TO AUTOMATICALLY OPEN A PAGE IN THE TOP WINDOW #
# #
##################################################################################
*/
/**
* Opens the current page in the top window.
*/
function openInTopWindow() {
if (isPageInFrame()) {
window.open(window.location.href, "_top");
}
}
/*
##################################################################################
# #
# FUNCTIONS TO SHOW SCROLLING TEXT IN STATUS BAR #
# #
##################################################################################
*/
/**
* Starts a scrolling message on the status bar.
*
* @param message The message to show
*/
function startScroller(message) {
scrollText = message;
timerOne = window.setTimeout("scroller(100)", 500);
}
/**
* Shows a scrolling message on the status bar.
*
*
The message to show is defined in a global variable
* named scrollText.
*
* @param seed The seed in milliseconds
*
* Copyright (C)1996 Web Integration Systems, Inc.
* DBA Websys, Inc. All Rights Reserved.
* This applet can be re-used or modified, if credit
* is given in the source code.
*/
function scroller(seed) {
var msg = scrollText;
var out = " ";
var c = 1;
if (100 < seed) {
seed--;
var cmd = "scroller(" + seed + ")";
timerTwo = window.setTimeout(cmd, 100);
} else if (seed <= 100 && seed > 0) {
for (c=0;c= seed) {
if (-seed < msg.length) {
out += msg.substring(-seed, msg.length);
seed--;
var cmd = "scroller(" + seed + ")";
window.status = out;
timerTwo = window.setTimeout(cmd, 100);
} else {
window.status = " ";
timerTwo = window.setTimeout("scroller(100)", 75);
}
}
}
/*
##################################################################################
# #
# DATE AND TIME FUNCTIONS #
# #
##################################################################################
*/
/**
* Returns the day in the week.
*
* @param date The date to get the week day from
* @return String The day in the week
*/
function getWeekday(date) {
return (DAY_ARRAY[date.getDay()]);
}
/**
* Returns the month in the year.
*
* @param date The date to get the month from
* @return String The month in the year
*/
function getMonth(date) {
return(MONTH_ARRAY[date.getMonth()]);
}
/**
* Returns the year in a millenium proof manner.
*
* @param date The date to get the year from
* @return String The year
*/
function getYear(date) {
var this_year = date.getYear();
if (1900 > this_year) {
return(this_year + 1900);
} else {
return(this_year);
}
}
/**
* Puts the current time in a field called time
* in a form called timeform in the document it is
* called from every second.
*/
function showTime() {
var timerID = null;
var timerRunning = false;
var now = new Date();
var hours = now.getHours();
var minutes = now.getMinutes();
var seconds = now.getSeconds();
var timevalue = " " + ((10 > hours) ? "0" : "") + hours;
if (timerRunning) {
clearTimeout(timerID);
}
timerRunning = false;
timevalue += ((10 > minutes) ? ":0" : ":") + minutes;
timevalue += ((10 > seconds) ? ":0" : ":") + seconds;
document.timeform.time.value = timevalue;
timerID = setTimeout("showTime()", 1000);
timerRunning = true;
}
/**
* Returns a greeting text, dependent on the hour in the day.
*
* @param date The date to work with
* @return String The greeting
*/
function getGreeting(date) {
var hours = date.getHours();
var greeting_text = "";
if (12 > hours) {
greeting_text = "Good morning";
} else if (12 <= hours && 18 > hours) {
greeting_text = "Good afternoon";
} else {
greeting_text = "Good evening";
}
return(greeting_text);
}
/*
##################################################################################
# #
# FUNCTIONS FOR (SUPPRESSING) HINTS WHEN POINTING AT LINKS #
# #
##################################################################################
*/
/**
* Erases any text in the status bar.
*/
function erase() {
window.status = "";
}
/*
##################################################################################
# #
# FUNCTION TO CHANGE THE IMAGES IN THE MAIN MENU #
# #
##################################################################################
*/
/**
* Performs a preload of a collection of pictures.
*
* @param picList The collection of picture filenames
* @param baseUrl The base URL for the pictures
*/
function preloadImages(picList, baseUrl) {
var pics = new ArrayObject();
var picture = null;
if (isBrowserRollCapable()) {
for (var i = 0; i < picList.length; i++) {
picture = new Image();
picture.src = baseUrl + picList[i];
pics.add(picture);
}
}
return pics;
}
/**
* Performs functionality necessary when an image is clicked on.
*
* @param index The index of the image
* @param baseUrl The base URL for the image
*/
function clickImage(index, baseUrl) {
overImage(index, 2, baseUrl);
top.focus();
}
/**
* Performs functionality necessary when a mouse cursor is hovering over an image.
*
* @param index The index of the image
* @param active Indicates the image mode:
* 0 mouse over
* 1 mouse out
* 2 clicked
* @param baseUrl The base URL for the image
*/
function overImage(index, active, baseUrl) {
if (isBrowserRollCapable()) {
var source = pics[index * 3 + active].src;
var newImage = baseUrl + source.substring(source.indexOf("idx"));
document.images[index].src = newImage;
}
}
/*
##################################################################################
# #
# FUNCTION TO PLAY THE BACKGROUND MUSIC, DEPENDENT ON WHAT BROWSER IS BEING USED #
# #
##################################################################################
*/
/**
* Takes care of playing music in an HTML page for Internet Explorer
* by writing a BGSOUND tag to the document.
*
* Because this will only function in a browser other than
* IE 3.0, the functioning is dependent on the browser type/version.
*
* @param url The URL to the music clip
* @param loop The number of times to repeat the clip, -1 or infinite
* for continuous playing
*/
function playMusicIE(url, loop) {
// if browser is IE then use BGSOUND-tag
// if IE version is 3.0 document.write in library will make IE crash
if ( (-1 != navigator.userAgent.indexOf("MSIE"))
&& (!isBrowserIE30())) {
var tag_text = "";
document.write(tag_text);
}
}
/**
* Takes care of playing music in an HTML page for browsers other than
* Internet Explorer by writing an EMBED tag to the document.
*
* @param url The URL to the music clip
* @param loop The number of times to repeat the clip, -1 or infinite
* for continuous playing
*/
function playMusic(url, loop) {
// if browser is not IE then use EMBED
if (-1 == navigator.userAgent.indexOf("MSIE")) {
var tag_text = "";
if (-1 == loop) {
loop = "true";
} else {
loop = "false";
}
tag_text = "