/**
* Global vars
*/
__AutoComplete = new Array();

// Basic UA detection
isIE = document.all ? true : false;
isGecko = navigator.userAgent.toLowerCase().indexOf('gecko') != -1;
isOpera = navigator.userAgent.toLowerCase().indexOf('opera') != -1;


/**
* Attachs the autocomplete object to a form element. Sets
* onkeypress event on the form element.
* 9597495229
* @param string formElement Name of form element to attach to
* @param array  data        Array of strings of which to use as the autocomplete data
*/

function AutoComplete_Create (id, data)
{
__AutoComplete[id] = {'data':data,
'isVisible':false,
'element':document.getElementById(id),
'dropdown':null,
'highlighted':null};

__AutoComplete[id]['element'].setAttribute('autocomplete', 'off');

__AutoComplete[id]['element'].onkeydown  = function(e) {return AutoComplete_KeyDown(this.getAttribute('id'), e);}
__AutoComplete[id]['element'].onkeyup    = function(e) {return AutoComplete_KeyUp(this.getAttribute('id'), e);}
__AutoComplete[id]['element'].onkeypress = function(e) {if (!e) e = window.event; if (e.keyCode == 13 || isOpera) return false;}
__AutoComplete[id]['element'].ondblclick = function() {AutoComplete_ShowDropdown(this.getAttribute('id'));}
__AutoComplete[id]['element'].onclick    = function(e) {if (!e) e = window.event; e.cancelBubble = true; e.returnValue = false;}

// Hides the dropdowns when document clicked
var docClick = function()
{
 for (id in __AutoComplete)
 {
    AutoComplete_HideDropdown(id);
 }
}

if (document.addEventListener)
{
document.addEventListener('click', docClick, false);
} else if (document.attachEvent) {
document.attachEvent('onclick', docClick, false);
}

// Max number of items shown at once
if (arguments[2] != null) {
__AutoComplete[id]['maxitems'] = arguments[2];
__AutoComplete[id]['firstItemShowing'] = 0;
__AutoComplete[id]['lastItemShowing']  = arguments[2] - 1;
}

AutoComplete_CreateDropdown(id);

// Prevent select dropdowns showing thru
if (isIE) {
__AutoComplete[id]['iframe'] = document.createElement('iframe');
__AutoComplete[id]['iframe'].id = id +'_iframe';
__AutoComplete[id]['iframe'].style.position = 'absolute';
__AutoComplete[id]['iframe'].style.top = '0';
__AutoComplete[id]['iframe'].style.left = '0';
__AutoComplete[id]['iframe'].style.width = '0px';
__AutoComplete[id]['iframe'].style.height = '0px';
__AutoComplete[id]['iframe'].style.zIndex = '98';
__AutoComplete[id]['iframe'].style.visibility = 'hidden';

__AutoComplete[id]['element'].parentNode.insertBefore(__AutoComplete[id]['iframe'], __AutoComplete[id]['element']);
}
}


/**
* Creates the dropdown layer
* 
* @param string id The form elements id. Used to identify the correct dropdown.
*/
function AutoComplete_CreateDropdown(id)
{
var left  = AutoComplete_GetLeft(__AutoComplete[id]['element']);
var top   = AutoComplete_GetTop(__AutoComplete[id]['element']) + __AutoComplete[id]['element'].offsetHeight;
var width = __AutoComplete[id]['element'].offsetWidth;

__AutoComplete[id]['dropdown'] = document.createElement('div');
__AutoComplete[id]['dropdown'].className = 'autocomplete'; // Don't use setAttribute()

__AutoComplete[id]['element'].parentNode.insertBefore(__AutoComplete[id]['dropdown'], __AutoComplete[id]['element']);

// Position it
__AutoComplete[id]['dropdown'].style.left       = left + 'px';
__AutoComplete[id]['dropdown'].style.top        = top + 'px';
__AutoComplete[id]['dropdown'].style.width      = width + 'px';
__AutoComplete[id]['dropdown'].style.zIndex     = '99';
__AutoComplete[id]['dropdown'].style.visibility = 'hidden';
}


/**
* Gets left coord of given element
* 
* @param object element The element to get the left coord for
*/
function AutoComplete_GetLeft(element)
{
var curNode = element;
var left    = 0;

do {
left += curNode.offsetLeft;
curNode = curNode.offsetParent;

} while(curNode.tagName.toLowerCase() != 'body');

return left;
}


/**
* Gets top coord of given element
* 
* @param object element The element to get the top coord for
*/
function AutoComplete_GetTop(element)
{
var curNode = element;
var top    = 0;

do {
top += curNode.offsetTop;
curNode = curNode.offsetParent;

} while(curNode.tagName.toLowerCase() != 'body');

return top;
}


/**
* Shows the dropdown layer
* 
* @param string id The form elements id. Used to identify the correct dropdown.
*/
function AutoComplete_ShowDropdown(id)
{
    AutoComplete_HideAll();

    var value = __AutoComplete[id]['element'].value;
    var toDisplay = new Array();
    var newDiv    = null;
    var text      = null;
    var numItems  = __AutoComplete[id]['dropdown'].childNodes.length;

    // Remove all child nodes from dropdown
    while(__AutoComplete[id]['dropdown'].childNodes.length > 0)
    {
        __AutoComplete[id]['dropdown'].removeChild(__AutoComplete[id]['dropdown'].childNodes[0]);
    }

    if(value.length>=3)
    {
        var new_var = null;
        
        // Go thru data searching for matches
        for(i=0; i<__AutoComplete[id]['data'].length; ++i)
        {
            new_var = __AutoComplete[id]['data'][i].split('-');

            if(new_var[0].toLowerCase().trim()== value.toLowerCase() || new_var[1].trim().toLowerCase().indexOf(value.toLowerCase())==0)
            {
                toDisplay[toDisplay.length] = __AutoComplete[id]['data'][i];
            }
            else
            {
                if (__AutoComplete[id]['data'][i].substr(0, value.length) == value)
                {
                    toDisplay[toDisplay.length] = __AutoComplete[id]['data'][i];
                }
            }
        }

        // No matches?
        if (toDisplay.length == 0)
        {
            for(i=0; i<__AutoComplete[id]['data'].length; ++i)
            {
                new_var = __AutoComplete[id]['data'][i].split('-');
            
                if(new_var[1].trim().toLowerCase().indexOf(value.toLowerCase())>0)
                {
                    toDisplay[toDisplay.length] = __AutoComplete[id]['data'][i];
                }
            }
            
            if(toDisplay.length==0)
            {
                alert("No matches found");
                AutoComplete_HideDropdown(id);
                return;
            }
        }
    }


    // Add data to the dropdown layer
    for (i=0; i<toDisplay.length; ++i)
    {
        newDiv = document.createElement('div');
        newDiv.className = 'autocomplete_item'; // Don't use setAttribute()
        newDiv.setAttribute('id', 'autocomplete_item_' + i);
        newDiv.setAttribute('index', i);
        newDiv.style.zIndex = '99';

        // Scrollbars are on display ?
        if (toDisplay.length > __AutoComplete[id]['maxitems'] && navigator.userAgent.indexOf('MSIE') == -1)
        {
            newDiv.style.width = __AutoComplete[id]['element'].offsetWidth - 22 + 'px';
        }

        newDiv.onmouseover = function() {AutoComplete_HighlightItem(__AutoComplete[id]['element'].getAttribute('id'), this.getAttribute('index'));};
        newDiv.onclick     = function() {AutoComplete_SetValue(__AutoComplete[id]['element'].getAttribute('id')); AutoComplete_HideDropdown(__AutoComplete[id]['element'].getAttribute('id'));}

        text   = document.createTextNode(toDisplay[i]);
        newDiv.appendChild(text);

        __AutoComplete[id]['dropdown'].appendChild(newDiv);
    }


    // Too many items?
    if (toDisplay.length > __AutoComplete[id]['maxitems'])
    {
        __AutoComplete[id]['dropdown'].style.height = (__AutoComplete[id]['maxitems'] * 15) + 2 + 'px';

    }
    else
    {
        __AutoComplete[id]['dropdown'].style.height = '';
    }

    /**
    * Set left/top in case of document movement/scroll/window resize etc
    */
    __AutoComplete[id]['dropdown'].style.left = AutoComplete_GetLeft(__AutoComplete[id]['element']) + 10;
    __AutoComplete[id]['dropdown'].style.top  = AutoComplete_GetTop(__AutoComplete[id]['element']) + __AutoComplete[id]['element'].offsetHeight + 15;

    
    if(value.length>=3)
    {
        // Show the iframe for IE
        if (isIE)
        {
            __AutoComplete[id]['iframe'].style.top    = __AutoComplete[id]['dropdown'].style.top;
            __AutoComplete[id]['iframe'].style.left   = __AutoComplete[id]['dropdown'].style.left;
            __AutoComplete[id]['iframe'].style.width  = __AutoComplete[id]['dropdown'].offsetWidth;
            __AutoComplete[id]['iframe'].style.height = __AutoComplete[id]['dropdown'].offsetHeight;

            __AutoComplete[id]['iframe'].style.visibility = 'visible';
        }


        // Show dropdown
        if (!__AutoComplete[id]['isVisible'])
        {
            __AutoComplete[id]['dropdown'].style.visibility = 'visible';
            __AutoComplete[id]['isVisible'] = true;
        }
    }
    
    // If now showing less items than before, reset the highlighted value
    if (__AutoComplete[id]['dropdown'].childNodes.length != numItems)
    {
        // __AutoComplete[id]['highlighted'] = null;
        AutoComplete_HighlightItem(id , 0);
    }
}


/**
* Hides the dropdown layer
* 
* @param string id The form elements id. Used to identify the correct dropdown.
*/
function AutoComplete_HideDropdown(id)
{
if (__AutoComplete[id]['iframe']) {
__AutoComplete[id]['iframe'].style.visibility = 'hidden';
}


__AutoComplete[id]['dropdown'].style.visibility = 'hidden';
__AutoComplete[id]['highlighted'] = null;
__AutoComplete[id]['isVisible']   = false;
}


/**
* Hides all dropdowns
*/
function AutoComplete_HideAll()
{
for (id in __AutoComplete) {
AutoComplete_HideDropdown(id);
}
}


/**
* Highlights a specific item
* 
* @param string id    The form elements id. Used to identify the correct dropdown.
* @param int    index The index of the element in the dropdown to highlight
*/
function AutoComplete_HighlightItem(id, index)
{
if (__AutoComplete[id]['dropdown'].childNodes[index]) {
for (var i=0; i<__AutoComplete[id]['dropdown'].childNodes.length; ++i) {
if (__AutoComplete[id]['dropdown'].childNodes[i].className == 'autocomplete_item_highlighted') {
__AutoComplete[id]['dropdown'].childNodes[i].className = 'autocomplete_item';
}
}

__AutoComplete[id]['dropdown'].childNodes[index].className = 'autocomplete_item_highlighted';
__AutoComplete[id]['highlighted'] = index;
}
}


/**
* Highlights the menu item with the given index
* 
* @param string id    The form elements id. Used to identify the correct dropdown.
* @param int    index The index of the element in the dropdown to highlight
*/
function AutoComplete_Highlight(id, index)
{
    // Out of bounds checking
    if (index == 1 && __AutoComplete[id]['highlighted'] == __AutoComplete[id]['dropdown'].childNodes.length - 1)
    {
        __AutoComplete[id]['dropdown'].childNodes[__AutoComplete[id]['highlighted']].className = 'autocomplete_item';
        __AutoComplete[id]['highlighted'] = null;
    }
    else if (index == -1 && __AutoComplete[id]['highlighted'] == 0)
    {
        __AutoComplete[id]['dropdown'].childNodes[0].className = 'autocomplete_item';
        __AutoComplete[id]['highlighted'] = __AutoComplete[id]['dropdown'].childNodes.length;
    }

    // Nothing highlighted at the moment
    if(__AutoComplete[id]['highlighted'] == null)
    {
        __AutoComplete[id]['dropdown'].childNodes[0].className = 'autocomplete_item_highlighted';
        __AutoComplete[id]['highlighted'] = 0;
    }
    else
    {
        if (__AutoComplete[id]['dropdown'].childNodes[__AutoComplete[id]['highlighted']])
        {
            __AutoComplete[id]['dropdown'].childNodes[__AutoComplete[id]['highlighted']].className = 'autocomplete_item';
        }

        var newIndex = __AutoComplete[id]['highlighted'] + index;

        if (__AutoComplete[id]['dropdown'].childNodes[newIndex])
        {
            __AutoComplete[id]['dropdown'].childNodes[newIndex].className = 'autocomplete_item_highlighted';

            __AutoComplete[id]['highlighted'] = newIndex;
        }
    }
}


/**
* Sets the input to a given value
* 
* @param string id    The form elements id. Used to identify the correct dropdown.
*/
function AutoComplete_SetValue(id)
{
__AutoComplete[id]['element'].value = __AutoComplete[id]['dropdown'].childNodes[__AutoComplete[id]['highlighted']].innerHTML;
}


/**
* Checks if the dropdown needs scrolling
* 
* @param string id    The form elements id. Used to identify the correct dropdown.
*/
function AutoComplete_ScrollCheck(id)
{
// Scroll down, or wrapping around from scroll up
if (__AutoComplete[id]['highlighted'] > __AutoComplete[id]['lastItemShowing']) {
__AutoComplete[id]['firstItemShowing'] = __AutoComplete[id]['highlighted'] - (__AutoComplete[id]['maxitems'] - 1);
__AutoComplete[id]['lastItemShowing']  = __AutoComplete[id]['highlighted'];
}

// Scroll up, or wrapping around from scroll down
if (__AutoComplete[id]['highlighted'] < __AutoComplete[id]['firstItemShowing']) {
__AutoComplete[id]['firstItemShowing'] = __AutoComplete[id]['highlighted'];
__AutoComplete[id]['lastItemShowing']  = __AutoComplete[id]['highlighted'] + (__AutoComplete[id]['maxitems'] - 1);
}

__AutoComplete[id]['dropdown'].scrollTop = __AutoComplete[id]['firstItemShowing'] * 15;
}


/**
* Function which handles the keypress event
* 
* @param string id    The form elements id. Used to identify the correct dropdown.
*/
function AutoComplete_KeyDown(id)
{
// Mozilla
if (arguments[1] != null) {
event = arguments[1];
}

var keyCode = event.keyCode;

switch (keyCode) {

// Return/Enter
case 13:
if (__AutoComplete[id]['highlighted'] != null) {
AutoComplete_SetValue(id);
AutoComplete_HideDropdown(id);
}

event.returnValue = false;
event.cancelBubble = true;
break;

// Escape
case 27:
AutoComplete_HideDropdown(id);
event.returnValue = false;
event.cancelBubble = true;
break;

// Up arrow
case 38:
if (!__AutoComplete[id]['isVisible']) {
AutoComplete_ShowDropdown(id);
}

AutoComplete_Highlight(id, -1);
AutoComplete_ScrollCheck(id, -1);
return false;
break;

// Tab
case 9:
if (__AutoComplete[id]['isVisible'])
{
    AutoComplete_SetValue(id);
    AutoComplete_HideDropdown(id);
}
return;

// Down arrow
case 40:

if (!__AutoComplete[id]['isVisible']) 
{
AutoComplete_ShowDropdown(id);
}

AutoComplete_Highlight(id, 1);
//AutoComplete_ScrollCheck(id, 1);
return false;
break;
}
}


/**
* Function which handles the keyup event
* 
* @param string id    The form elements id. Used to identify the correct dropdown.
*/
function AutoComplete_KeyUp(id)
{
// Mozilla
if (arguments[1] != null) {
event = arguments[1];
}

var keyCode = event.keyCode;

switch (keyCode) {
case 13:
event.returnValue = false;
event.cancelBubble = true;
break;

case 27:
AutoComplete_HideDropdown(id);
event.returnValue = false;
event.cancelBubble = true;
break;

case 38:
case 40:
return false;
break;

default:
AutoComplete_ShowDropdown(id);
break;
}
}

/**
* Returns whether the dropdown is visible
* 
* @param string id    The form elements id. Used to identify the correct dropdown.
*/
function AutoComplete_isVisible(id)
{
return __AutoComplete[id]['dropdown'].style.visibility == 'visible';
}