fancybox-with-cookie-wp-enqueue.php

<?php // you can probably leave out the opening/ closing PHP tags, depending on the format of your functions.php

// References:
// http://codex.wordpress.org/Function_Reference/wp_enqueue_script
// http://codex.wordpress.org/Function_Reference/wp_enqueue_style

// it's a good idea to change "my_scripts_method" to something specific to your site or theme.
function my_scripts_method() {
	
	if ( !is_admin() ) : // make sure we're not in the admin
		
		// these first two chunks load the Fancybox JS and CSS files
		wp_enqueue_script(
			'fancybox',
			// the file path below assumes this is in your theme in a /js/ folder
			get_stylesheet_directory_uri() . '/js/jquery.fancybox.pack.js', 
			// the line below ensures this loads after jQuery
			array( 'jquery' )
		);
		wp_enqueue_style(
			'fancybox-css',
			get_stylesheet_directory_uri() . '/js/jquery.fancybox.css'
		);
		
		// this final chunk loads the cookie JS file
		wp_enqueue_script(
			'cookie',
			get_stylesheet_directory_uri() . '/js/jquery.cookie.js',
			array( 'jquery' )
		);
	
	endif; // end check if we're in the admin
}

// remember to change "my_scripts_method" if you changed it above
add_action( 'wp_enqueue_scripts', 'my_scripts_method' );
?>

fancybox-with-cookie.js

(function($) {
	// set a variable for the cookie check
	var check_cookie = $.cookie('popup_box');
	
	// check whether the cookie is already set for this visitor
	if( check_cookie != 'active' ){
		// if the cookie does not exist do the following:
		
		// (1) set the cookie so it's there for future visits (including an expiration time in days)
		$.cookie('popup_box', 'active', { 
			expires: 30,
			path: '/'
		});
		
		// (2) trigger the fancybox pop up, specifying that it's inline
		$( '#trigger' ).fancybox({
			type: 'inline'
		});
		$('#trigger').eq(0).trigger('click'); // make the click event happen on load
	}
})(jQuery); // this is a noconflict wrapper for WP