max_num_pages problem

///////////////////////// Plugin PHP
<?php
/**
 * Plugin Name: PBD AJAX Load Posts
 * Plugin URI: http://www.problogdesign.com/
 * Description: Load the next page of posts with AJAX.
 * Version: 0.1
 * Author: Pro Blog Design
 * Author URI: http://www.problogdesign.com/
 */

 /**
  * Initialization. Add our script if needed on this page.
  */
 function pbd_alp_init() {
 	global $wp_query;

 	// Add code to index pages.
 	if( !is_singular() ) {
 		// Queue JS
 		wp_enqueue_script(
 			'pbd-alp-load-posts',
 			plugin_dir_url( __FILE__ ) . 'js/load-posts.js',
 			array('jquery'),
 			'1.0',
 			true
 		);



 		// What page are we on? And what is the pages limit?
 		$max = $wp_query->max_num_pages;
 		$paged = ( get_query_var('paged') > 1 ) ? get_query_var('paged') : 1;

 		// Add some parameters for the JS.
 		wp_localize_script(
 			'pbd-alp-load-posts',
 			'pbd_alp',
 			array(
 				'startPage' => $paged,
 				'maxPages' => $max,
 				'nextLink' => next_posts($max, false)
 			)
 		);
 	}
 }
 add_action('template_redirect', 'pbd_alp_init');

 ?>

/////////////// Plugin JS
jQuery(document).ready(function($) {

	// The number of the next page to load (/page/x/).
	var pageNum = parseInt(pbd_alp.startPage) + 1;

	// The maximum number of pages the current query can return.
	var max = parseInt(pbd_alp.maxPages);

	// The link of the next page of posts.
	var nextLink = pbd_alp.nextLink;

	// To check to see what the max is outputing
	console.log(max);
	/**
	 * Replace the traditional navigation with our own,
	 * but only if there is at least one page of new posts to load.
	 */
	if(pageNum <= max) {
		// Insert the "More Posts" link.
		$('#content')
			.append('<div class="pbd-alp-placeholder-'+ pageNum +'"></div>')
			.append('<p id="pbd-alp-load-posts"><a href="#">Load More Posts</a></p>');

		// Remove the traditional navigation.
		$('.pagination').remove();
	}


	/**
	 * Load new posts when the link is clicked.
	 */
	$('#pbd-alp-load-posts a').click(function() {

		// Are there more posts to load?
		if(pageNum <= max) {

			// Show that we're working.
			$(this).text('Loading posts...');

			$('.pbd-alp-placeholder-'+ pageNum).load(nextLink + ' .gallery-holder',
				function() {
					$(this).hide().fadeIn(800);
					// Update page number and nextLink.
					pageNum++;
					nextLink = nextLink.replace(/\/page\/[0-9]*/, '/page/'+ pageNum);

					// Add a new placeholder, for when user clicks again.
					$('#pbd-alp-load-posts')
						.before('<div class="pbd-alp-placeholder-'+ pageNum +'"></div>')

					// Update the button message.
					if(pageNum <= max) {
						$('#pbd-alp-load-posts a').text('Load More Posts');
					} else {
						$('#pbd-alp-load-posts a').text('No more posts to load.');
					}
				}
			);
		} else {
			$('#pbd-alp-load-posts a').append('.');
		}

		return false;
	});
});

///////////// The category template
<?php get_header(); ?>

<section>

    <hgroup>
        <h1><?php single_cat_title() ?></h1>

    </hgroup>
		<ul class="sub-cat">
		<?php wp_list_categories('show_option_none=&orderby=name&show_count=1&hide_empty=1&use_desc_for_title=1&child_of='.$cat.'&title_li='); ?>
		</ul>

	<?php
		echo '<div class="gallery" id="content">';
		$paged = (get_query_var('paged')) ? get_query_var('paged') : 1;
		$wp_query = new WP_Query();
		if(is_mobile()) {
			$wp_query->query('cat='.$cat.'&post_status=publish&posts_per_page=10&showpost=10&paged=' . $paged);
		} else {
			$wp_query->query('cat='.$cat.'&post_status=publish&posts_per_page=12&showpost=12&paged=' . $paged);
		}
		if ($wp_query->have_posts()) :
		while ($wp_query->have_posts()) : $wp_query->the_post();
		echo '<div class="gallery-holder">';
		echo '<a href="';
		echo the_permalink();
		echo '">';
		if(is_mobile()) {
			the_post_thumbnail('gallery-mobile');
		} else {
			the_post_thumbnail('gallery');
		}
		echo '<div class="desc-container"><div class="photo-desc">';
		echo '<h2>';
		the_title();
		echo '</h2>';
		the_excerpt();
		echo '</div></div></a></div>';
		endwhile;
		endif;
		echo '</div>';

		if (function_exists("pagination")) {
		pagination($additional_loop->max_num_pages);
		}

	?>


</section>
<?php get_footer(); ?>

//////////////// Functions file
<?php
add_theme_support('post-thumbnails');

add_image_size( 'gallery', 281, 260, true );
add_image_size( 'main', 984, 800, false );
add_image_size( 'home', 984, 400, true );
add_image_size( 'recent', 100, 100, true );

add_image_size( 'gallery-mobile', 300, 200, true );
add_image_size( 'main-mobile', 300, 0, false );
add_image_size( 'home-mobile', 300, 200, true );
add_image_size( 'recent-mobile', 150, 150, true );

add_theme_support( 'menus' );

function custom_excerpt_length( $length ) {
	return 20;
}

add_filter( 'excerpt_length', 'custom_excerpt_length', 999 );

function get_cat_slug($cat_id) {
	$cat_id = (int) $cat_id;
	$category = $get_category($cat_id);
	return $category->slug;
}

$new_defaults = array(
        'title_reply' => '<h4>Send</h4>',
        'comment_notes_after' => '',
        'comment_field' => '<p class="comment-form-comment"><label for="comment">' . _x( 'Comment', 'noun' ) . '</label><textarea id="comment" name="comment" cols="45" rows="8" aria-required="true"></textarea></p>',
	'title_reply' => '',
	'comment_notes_before' => '',
);


function pagination($pages = '', $range = 2) {
     $showitems = ($range * 2)+1;

     global $paged;
     if(empty($paged)) $paged = 1;

     if($pages == '')
     {
         global $wp_query;
         $pages = $wp_query->max_num_pages;
         if(!$pages)
         {
             $pages = 1;
         }
     }

     if(1 != $pages)
     {
         echo "<div class=\"pagination\">";

	if(is_mobile()) {
	 	if($paged > 2 && $paged > $range+1 && $showitems < $pages) echo "<a href='".get_pagenum_link(1)."'>&laquo;</a>";
         	if($paged > 1) echo "<a href='".get_pagenum_link($paged - 1)."'>&lsaquo;</a>";
	} else {
	 	if($paged > 2 && $paged > $range+1 && $showitems < $pages) echo "<a href='".get_pagenum_link(1)."'>&laquo; First</a>";
         	if($paged > 1) echo "<a href='".get_pagenum_link($paged - 1)."'>&lsaquo; Previous</a>";
	}

         for ($i=1; $i <= $pages; $i++)
         {
             if (1 != $pages &&( !($i >= $paged+$range+1 || $i <= $paged-$range-1) || $pages <= $showitems ))
             {
                 echo ($paged == $i)? "<span class=\"current\">".$i."</span>":"<a href='".get_pagenum_link($i)."' class=\"inactive\">".$i."</a>";
             }
         }

	if(is_mobile()) {
         	if ($paged < $pages) echo "<a href=\"".get_pagenum_link($paged + 1)."\">&rsaquo;</a>";
	 	if ($paged < $pages-1 &&  $paged+$range-1 < $pages && $showitems < $pages) echo "<a href='".get_pagenum_link($pages)."'>&raquo;</a>";
        	 echo "</div>\n";
	} else {
         	if ($paged < $pages) echo "<a href=\"".get_pagenum_link($paged + 1)."\">Next &rsaquo;</a>";
	 	if ($paged < $pages-1 &&  $paged+$range-1 < $pages && $showitems < $pages) echo "<a href='".get_pagenum_link($pages)."'>Last &raquo;</a>";
         	echo "</div>\n";
	}

     }
}
?>