/**
 * Assorted site-level JavaScript utilities.
 */

/**
 * Processes the current document's links and changes their style if their hrefs
 * match the given string.
 */
var updateLinkStyles = function(pattern, className) {
    var i;
    for (i = 0; i < document.links.length; i += 1) {
        if (document.links[i].href.match(pattern)) {
            document.links[i].className = className;
        }
    }
};

/**
 * Prints the content of the current window.
 */
var printThis = function() {
    if (window.print) {
        window.print();
    }
};

/**
 * e-mails the URL of the current window.
 */
var emailThis = function() {
    window.location = "mailto:?subject=" + document.title + "&body=\n\t" + window.location + "\n";
};

/**
 * Updates the given object's HTML with the site's information. The second
 * argument, level, states how far down the document's URL to travel before
 * cutting out the rest; this allows a "root site" of sorts to be defined. A
 * level of zero will return only the URL's server name.
 */
var updateSiteHome = function(id, level) {
    // Extract the URL's protocol.
    var protPath = document.URL.split("://");
    var siteHome = protPath[0] + "://";

    // Next, reconstruct the URL only up to the given level.
    var steps = protPath[1].split("/");
    for ( var i = 0; (i < level + 1) && (i < steps.length); i += 1) {
        siteHome = siteHome + steps[i];
        if ((i < level) && (i < steps.length - 1)) {
            siteHome = siteHome + "/";
        }
    }

    var siteBlock = document.getElementById(id);
    siteBlock.innerHTML = siteHome;
    siteBlock.href = siteHome;
};

/**
 * Updates the given object's HTML with the page's lastModified property.
 */
var updateLastModified = function(id) {
    var modBlock = document.getElementById(id);
    modBlock.innerHTML = document.lastModified;
};

/**
 * Unconditionally makes the given element visible.
 */
var makeVisible = function(element) {
    element.visible = true;
    element.style.display = "block";
};

/**
 * Unconditionally makes the given element invisible.
 */
var makeInvisible = function(element) {
    element.visible = false;
    element.style.display = "none";
};

/**
 * Toggles the visibility or invisibility of the element with the given ID.
 */
var hideAndSeek = function(id) {
    var target = document.getElementById(id);
    if (target.visible) {
        makeInvisible(target);
    } else {
        makeVisible(target);
    }
};

/**
 * Unconditionally makes the element with the given ID visible.
 */
var makeIdVisible = function(id) {
    makeVisible(document.getElementById(id));
};

/**
 * Unconditionally makes the element with the given ID invisible.
 */
var makeIdInvisible = function(id) {
    makeInvisible(document.getElementById(id));
};