');
// Calculate the number of grid lines needed
var overlayGridLines = overlay.children('.horiz'),
overlayGridLineHeight = parseFloat(overlayGridLines.css('height')) + parseFloat(overlayGridLines.css('border-bottom-width'));
// Break on zero line height
if (overlayGridLineHeight <= 0) return true;
// Add the remaining grid lines
var i, numGridLines = Math.floor(pageHeight / overlayGridLineHeight);
for (i = numGridLines - 1; i >= 1; i--) {
overlay.append('
');
}
// Check for saved state
var overlayCookie = readCookie(options.cookiePrefix + options.id);
if (typeof overlayCookie == 'string') {
var state = overlayCookie.split(',');
state[2] = Number(state[2]);
if ((typeof state[2] == 'number') && !isNaN(state[2])) {
classNumber = state[2].toFixed(0);
overlay.addClass(options.classPrefix + classNumber);
}
if (state[1] == 'F') {
overlayZState = 'F';
overlay.css('z-index', overlayZForeground);
}
if (state[0] == '1') {
overlayOn = true;
sticky = true;
overlay.show();
}
}
// Keyboard controls
$(document).bind('keydown', keydownHandler);
$(document).bind('keyup', keyupHandler);
/**
* Helpers
*/
function getModifier(e) {
if (options.modifierKey == null) return true; // Bypass by default
var m = true;
switch(options.modifierKey) {
case 'ctrl':
m = (e.ctrlKey ? e.ctrlKey : false);
break;
case 'alt':
m = (e.altKey ? e.altKey : false);
break;
case 'shift':
m = (e.shiftKey ? e.shiftKey : false);
break;
}
return m;
}
function getKey(e) {
var k = false, c = (e.keyCode ? e.keyCode : e.which);
// Handle keywords
if (c == 13) k = 'enter';
// Handle letters
else k = String.fromCharCode(c).toLowerCase();
return k;
}
function saveState() {
createCookie(options.cookiePrefix + options.id, (sticky ? '1' : '0') + ',' + overlayZState + ',' + classNumber, 1);
}
/**
* Event handlers
*/
function keydownHandler(e) {
var source = e.target.tagName.toLowerCase();
if ((source == 'input') || (source == 'textarea') || (source == 'select')) return true;
var m = getModifier(e);
if (!m) return true;
var k = getKey(e);
if (!k) return true;
switch(k) {
case options.showGridKey:
if (!overlayOn) {
overlay.show();
overlayOn = true;
}
else if (sticky) {
overlay.hide();
overlayOn = false;
sticky = false;
saveState();
}
break;
case options.holdGridKey:
if (overlayOn && !sticky) {
// Turn sticky overlay on
sticky = true;
saveState();
}
break;
case options.foregroundKey:
if (overlayOn) {
// Toggle sticky overlay z-index
if (overlay.css('z-index') == overlayZForeground) {
overlay.css('z-index', overlayZBackground);
overlayZState = 'B';
}
else {
overlay.css('z-index', overlayZForeground);
overlayZState = 'F';
}
saveState();
}
break;
case options.jumpGridsKey:
if (overlayOn && (options.numberOfGrids > 1)) {
// Cycle through the available grids
overlay.removeClass(options.classPrefix + classNumber);
classNumber++;
if (classNumber > options.numberOfGrids) classNumber = 1;
overlay.addClass(options.classPrefix + classNumber);
saveState();
}
break;
}
}
function keyupHandler(e) {
var m = getModifier(e);
if (!m) return true;
var k = getKey(e);
if (!k) return true;
switch(k) {
case options.showGridKey:
if (!sticky) {
overlay.hide();
overlayOn = false;
}
break;
}
}
}
/**
* Cookie functions
*
* By Peter-Paul Koch:
* http://www.quirksmode.org/js/cookies.html
*/
function createCookie(name,value,days) {
if (days) {
var date = new Date();
date.setTime(date.getTime()+(days*24*60*60*1000));
var expires = "; expires="+date.toGMTString();
}
else var expires = "";
document.cookie = name+"="+value+expires+"; path=/";
}
function readCookie(name) {
var nameEQ = name + "=";
var ca = document.cookie.split(';');
for(var i=0;i < ca.length;i++) {
var c = ca[i];
while (c.charAt(0)==' ') c = c.substring(1,c.length);
if (c.indexOf(nameEQ) == 0) return c.substring(nameEQ.length,c.length);
}
return null;
}
function eraseCookie(name) {
createCookie(name,"",-1);
}