Replace the New WP 3.5 Uploader with the Old Thickbox

old-upload-method.php

<?php

/**
 * Plugin Name: Old Upload Method
 * Plugin URI: http://wordpress.org/support/topic/is-there-a-way-to-disable-the-new-media-manager
 * Description: Replace the new media upload with the old thickbox
 * Author: A.Morita, brasofilo
 * Version: 1.2
 * License: GPLv2 or later
 * 
 * This program is free software; you can redistribute it and/or modify it under the terms of the GNU 
 * General Public License version 2, as published by the Free Software Foundation.  You may NOT assume 
 * that you can use any other version of the GPL.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without 
 * even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 */
if( function_exists( 'add_filter' ) )
	add_action( 'plugins_loaded', array( 'I_Want_The_Old_Uploader', 'get_object' ) );

/**
 * Add Tags and Categories taxonmies to Attachment with WP 3.5
 */
class I_Want_The_Old_Uploader
{
	static private $classobj;

	/**
	 * Constructor, init the functions inside WP
	 *
	 * @since   1.0.0
	 * @return  void
	 */
	public function __construct()
	{
		// Run only in editing pages
		global $pagenow;
		if( !in_array( $pagenow, array('post.php','post-new.php') ) )
			return;
		
		// Old Upload buttons and thickbox
		add_action( 'admin_head', array( $this, 'remove_media_buttons' ) );

		// Featured Image
		add_action( 'wp_default_scripts', array( $this, 'unset_media_views' ), 999, 1 );
		add_action( 'admin_head', array( $this, 'remove_wp_print_media_templates' ) );

		// Full screen behavior
		add_action( 'after_wp_tiny_mce', array( $this, 'fullscreen_media_button' ) );
	}


	/**
	 * Handler for the action 'init'. Instantiates this class.
	 *
	 * @since   1.0.0
	 * @access  public
	 * @return  $classobj
	 */
	public function get_object()
	{
		if( NULL === self::$classobj )
			self::$classobj = new self;

		return self::$classobj;
	}


	/**
	 * Old Upload Buttons & Thickbox
	 */
	public function remove_media_buttons()
	{
		remove_action( 'media_buttons', 'media_buttons' );
		add_action( 'media_buttons', array( $this, 'old_media_buttons' ) );
	}


	public function old_media_buttons( $editor_id = 'content' )
	{
		$context = apply_filters( 'media_buttons_context', __( 'Upload/Insert %s' ) );

		$img = '<img src="'
				. esc_url( admin_url( 'images/media-button.png?ver=20111005' ) )
				. '" width="15" height="15" />';

		echo '<a href="'
		. esc_url( get_upload_iframe_src() )
		. '" class="thickbox add_media" id="'
		. esc_attr( $editor_id )
		. '-add_media" title="'
		. esc_attr__( 'Add Media' )
		. '" onclick="return false;">'
		. sprintf( $context, $img )
		. '</a>';
	}


	/**
	 * Featured image
	 */
	public function unset_media_views( $scripts )
	{
		unset( $scripts->registered['media-views'] );
	}


	public function remove_wp_print_media_templates()
	{
		remove_action( 'admin_footer', 'wp_print_media_templates' );
		remove_action( 'wp_footer', 'wp_print_media_templates' );
	}


	/**
	 * Adjust Full Screen behavior
	 * Check if fullscreen exists avoids errors in pages without Editor support
	 * ie: pages where the regular content textarea is not enabled
	 */
	public function fullscreen_media_button()
	{
		?>
		<script type="text/javascript">
			if( undefined != fullscreen )
			{
				fullscreen.medialib = function() 
				{
					var href = jQuery('div#wp-content-media-buttons a.thickbox').attr('href') || '';
					tb_show('', href);
				}
			}
		</script>
		<?php
	}

}