// Display the text if it is not displayed; hide it if it is displayed
function showSection(section) {
    if (section.style.display == "none") {
        section.style.display = "";
    } else {
        section.style.display = "none";
    }
}

// Display the text if it is not displayed and change the arrow to point down
// Or hide the text again, and make the arrow point right
function expandWithArrow(section, arrow) {
    if (section.style.display == "none") {
        section.style.display = "";
        arrow.src = "help_style/arrowdn.gif";
    } else {
        section.style.display = "none";
        arrow.src = "help_style/arrowrt.gif";
    }
}


// Open all DIV tags containing a matching search string
function openDivTagsWithString(searchString) {
    var divTags = document.getElementsByTagName("DIV"); 	// get a handle on all the DIV tags in the document
    for (i = 0; i < divTags.length; i++) {	// loop through all the DIV tags
        var divText = divTags[i].outerHTML; 	// get a handle on all the HTML code within the current DIV tag, including the tag itself
        if (divText.indexOf(searchString) != -1) {	// if there's a match of the section number
            var divTagId = divTags[i].id; 	// get a handle on the ID of the current DIV tag
            var arrowTagId = divTagId.replace("section", "arrow"); 	// work out the corresponding arrow image ID
            divTags[i].style.display = "block"; 	// set the display style of the current DIV tag to be block (visible)
            if (divTags[i].className == "expanded") {	// if the DIV class is expanded, it has a corresponding arrow image
                document.images[arrowTagId].src = "help_style/arrowdn.gif"; 	// so change the image to use the down arrow
            }
        }
    }
}

// Extra search to expand all parent DIV tags if this is a nested DIV tag
function showSectionNoHide(section, arrow) {
    var searchString = 'id=' + section + ' ';
    openDivTagsWithString(searchString);
}


// Reload the page again so the page scrolls to the anchor
function scrollToAnchor(anchor) {
    location = '#' + anchor;
}





// Show all text when check box selected
function showAllText() {
    var lists = document.getElementsByTagName("DIV");
    for (i = 0; i < lists.length; i++) {
        lists[i].style.display = "";
    }
    var arrows = document.getElementsByTagName("IMG");
    for (i = 0; i < arrows.length; i++) {
        if (arrows[i].id.length > 0) {
            arrows[i].src = "help_style/arrowdn.gif";
        }
    }
}


// Hide all text when check box cleared
function hideAllText() {
    var lists = document.getElementsByTagName("DIV");
    for (i = 0; i < lists.length; i++) {
        lists[i].style.display = "none";
    }
    var arrows = document.getElementsByTagName("IMG");
    for (i = 0; i < arrows.length; i++) {
        if (arrows[i].id.length > 0) {
            arrows[i].src = "help_style/arrowrt.gif";
        }
    }
}


// Run these functions when the document loads
function finishDocument() {
    checkLocation();
    setCheckBoxState();
    hideSections();
    setVisibility();
    checkForHighlighting();
    checkForAnchor();
}


// Check whether the topic has been called from a context ID in the software, and if so,
// reload the topic without the parent CHM file name in the path.
// This function corrects the problem where the HHC doesn't auto-sync if you jump to a topic
// by using the syntax 'ms-its:<parent>.chm::/<child>.chm::/topics/<file>.htm>$global_<window>'
// in the parent's ALI file.
function checkLocation() {
    locationString = location.toString(); 	// get a handle on the current location (href) and convert it to a string
    if (locationString.indexOf('.chm::/') != locationString.lastIndexOf('.chm::/')) {	// if the 1st match of '.chm::/' does NOT match the location of the last match
        // i.e. there's only one instance
        startNumber = locationString.indexOf('.chm::/') + 7; // set the start point for the replacement string to the start of the child's CHM name
        // (the 1st character after the 1st '.chm::/')
        endNumber = locationString.length; 	// set the end point for the replacement string to the length of the whole string
        replacedString = 'ms-its:' + locationString.substring(startNumber, endNumber); 	// create a new string 
        // which is 'ms-its:' + the section of the location from the child's CHM to the end
        location = replacedString; 	// load the topic defined by the new string, which is the same topic but directly in the child CHM, so the TOC will auto-sync
    }
}


// Check whether there is hidden text in the document, and if not, disable the Expand all text check box and label
function setCheckBoxState() {
    var divTags = document.getElementsByTagName("DIV"); 	// get a handle on all the DIV tags in the document
    var formTags = document.getElementsByTagName("FORM"); 	// get a handle on all the FORM tags in the document
    if ((divTags.length == 0) && (formTags.length > 0)) {	// if there are no DIV tags in the document but there is a form
        document.form1.ShowAll.checked = true; // select the check box in the Expand all text form
        document.form1.ShowAll.disabled = true; 	// disable the check box
        checkboxLabel.className = "disabledlabel"; // make the check box label grey
    }
}


// Hide all DIV tags apart from ones to be expanded
function hideSections() {
    var sections = document.getElementsByTagName("DIV"); 	// get a handle on all the DIV tags in the document
    for (i = 0; i < sections.length; i++) {			// loop through all the DIV tags
        var sectionID = sections[i].id; // get a handle on the ID of the current DIV tag
        if (sectionID.indexOf("expanded") == -1) {	// if the string 'expanded' can't be found in the ID
            sections[i].style.display = "none"; // set the display style of the current DIV tag to be hidden
        }
    }
}


// Now that you've hidden the relevant DIV tags, set the BODY tag to be visible
function setVisibility() {
    body.style.visibility = "visible";
}


// When a page loads, check whether there is any search results highlighting, and if so,
// expand all the DIV tags that contain hits, and scroll to the first hit
function checkForHighlighting() {
    var tempHTML = document.body.innerHTML; 	// get a handle on all the HTML code between the BODY tags
    // if there's a match of the strings
    if ((tempHTML.indexOf('<FONT') != -1) && (tempHTML.indexOf('style="BACKGROUND-COLOR: #') != -1) && (tempHTML.indexOf('color=#ffffff') != -1)) {
        var divTags = document.getElementsByTagName("DIV"); 	// get a handle on all the DIV tags in the document
        var openDivTags = 0; // create a variable which will count the number of open DIV tags
        for (i = 0; i < divTags.length; i++) {	// loop through all the DIV tags
            var divText = divTags[i].innerHTML; // get a handle on all the HTML code within the current DIV tag
            // if there's a match of the strings
            if ((divText.indexOf('<FONT') != -1) && (divText.indexOf('style="BACKGROUND-COLOR: #') != -1) && (divText.indexOf('color=#ffffff') != -1)) {
                var divTagId = divTags[i].id; // get a handle on the ID of the current DIV tag
                var arrowTagId = divTagId.replace("section", "arrow"); 	// work out the corresponding arrow image ID
                divTags[i].style.display = "block"; // set the display style of the current DIV tag to be block (visible)
                if (divTags[i].className == "expanded") {	// if the DIV class is expanded, it has a corresponding arrow image
                    document.images[arrowTagId].src = "help_style/arrowdn.gif"; 	// so change the image to use the down arrow
                }
                openDivTags = openDivTags + 1;
            }
        }
        var fontTags = document.getElementsByTagName("FONT"); 	// get a handle on all the FONT tags in the document
        for (i = 0; i < fontTags.length; i++) {		// loop through all the FONT tags
            if ((fontTags[i].color == "#ffffff") && (fontTags[i].style.backgroundColor != -1)) {	// if there's a match of the strings
                fontTagToUse = fontTags[i]; // get a handle on the current FONT tag
                break; // then leave the loop
            }
        }
        var parentTag = fontTagToUse.parentElement; // get a handle on the current FONT tag's parent element (tag)
        if ((parentTag.tagName == 'B') || (parentTag.tagName == 'I') || (parentTag.tagName == 'A') || (parentTag.tagName == 'SPAN')) {	// if the parent tag is a B, I, A or SPAN
            parentTag.parentElement.scrollIntoView(); 	// scroll to the parent tag's parent tag, which will hopefully be a block level element
        } else {
            parentTag.scrollIntoView(); // otherwise, scroll to the parent tag, which will hopefully be a block level element
        }
        var formTags = document.getElementsByTagName("FORM"); 	// get a handle on all the FORM tags in the document
        if ((openDivTags == divTags.length) & (formTags.length > 0)) {		// if the number of open DIV tags equals the total number
            // i.e. they are all open, and there is a form
            document.form1.ShowAll.checked = true; 		// select the check box in the Expand all text form
        }
    }
}


// When a page loads, check whether the location includes an anchor, and if so,
// expand all the DIV tags that contain the anchor
function checkForAnchor() {
    // Extra search to expand all parent DIV tags if this is an anchor within the document
    locationString = location.toString(); 	// get a handle on the current location (href) and convert it to a string
    if (locationString.indexOf('.htm#') != -1) {	// if there is an anchor in the location
        startNumber = locationString.indexOf('.htm#') + 5; 	// set the start point for the anchor string to the start of the anchor number
        endNumber = locationString.length; // set the end point for the anchor string to the length of the whole string
        anchor = locationString.substring(startNumber, endNumber); 	// create a new string which is the section of the location from the start of the anchor to the end
        var searchString = '<A name=' + anchor + '></A>';
        openDivTagsForSpansWithString(searchString);
        openDivTagsWithString(searchString);
        location = '#' + anchor; // Now reload the page again so the page scrolls to the anchor
    }
}

// Open all DIV tags containing a matching search string
function openDivTagsForSpansWithString(searchString) {
    var spanTags = document.getElementsByTagName("SPAN"); 	// get a handle on all the SPAN tags in the document
    for (i = 0; i < spanTags.length; i++) {	// loop through all the SPAN tags
        var spanText = spanTags[i].outerHTML; 	// get a handle on all the HTML code within the current SPAN tag, including the tag itself
        if (spanText.indexOf(searchString) != -1) {	// if there's a match of the section number
            spanTags(i).click(); 	// click the SPAN tag to open its corresponding DIV tag
        }
    }
}


// Run finishDocument() function when the document loads. Trap error after printing multiple topics in HTML Help, when it can't find JS file & style sheet
function runOnLoadFunctions() {
    //window.onerror = trapError; 	// when you get an error, run the trapError function
    finishDocument(); 	// run the functions to finish the document
}

// Set the text to be visible before printing
function runBeforePrint() {
    body.style.visibility = 'visible'; 	// make body visible for printing
}

// Stop error messages appearing
//function trapError() {
//    return true; 	// do nothing: this stops an error message appearing
//}