Prepare Filtering Options as a Drupal Form

A client needed a bit more styling on the node admin form than was there. I needed the filtering options to match a normal drupal form so I could use its styles.
I've worked up the table header using drupal_render. In the process I added an autocomplete to the userFilter. I thought you might want to take a look over. At some point you could output this through a theme and let people alter it more if needed. I would normally give you a line break down, but there's just a ton of changes. It'd be over whelming. I'll just leave the parts commented out above the new methods. (Note that I did not do the 'add node.' I've had to disable that for reasons in another issue.)

 * Callback for generating nodeadmin page.
 */
function nodeadmin_page() {
  global $base_url;

  // build map of content type names
  $types = array();
		$types[''] = 'All';
  $ctypes = node_get_types();
  foreach ($ctypes as $ctype => $cdata) {
    $types[$ctype] = $cdata->name;
  }

  // generate content administration page
  /*
		$output = '<div>Filter by type: <select id="filterType"><option value="" selected>All</option>';
  foreach ($types as $ctype => $cname) {
    $output .= '<option value="' . $ctype .'">'. $cname .'</option>';
  }
  $output .= '</select></div>';
		*/
		$form = array();
		$form['type_filter'] = array(
			'#type' => 'select',
			'#title'	=>	'Filter by type',
			'#options' => $types,
			'#weight' => -5,
			'#id' => 'filterType',
		);
  //$output .= '<div>Filter by author: <input id="filterUser" type="text" size="20" value="" /></div>';
		$form['author_filter'] = array(
			'#type' => 'textfield',
			'#title' => 'Filter by user',
			'#autocomplete_path' => 'user/autocomplete',
			'#weight' => -4,
			'#id' => 'filterUser',
		);
  if (module_exists('search')) {
    //$output .= '<div>Filter by text content: <input id="filterText" type="text" size="20" value="" /></div>';
				$form['text_filter'] = array(
					'#type' => 'textfield',
					'#title' => 'Filter by text',
					'#weight' => -3,
					'#id' => 'filterText',
				);
  }
  //$output .= '<div>Results per page: <input id="optionLimit" type="text" size="6" value="50" /><span id="numberResults">&nbsp;</span><div id="pageResults"></div></div>';
		$form['limit'] = array(
			'#type' => 'textfield',
			'#title' => 'Results per page',
			'#value' => 50,
			'#weight' => -2,
			'#id'	=>	'optionLimit',
		);
		$form['numberResults'] = array(
			'#weight' => -1,
			'#value' => '<div id="pageResults"></div><span id="numberResults">&nbsp;</span>',
		);
 
		//$output .= '</div>';
		/*$output .= '<br/><div class="nodeadmin-addnode"><img src="'. $base_url .'/'. drupal_get_path('module', 'nodeadmin') .'/icons/doc-option-add.png" width="16" height="16" /> Add new content by type: <select id="addType"><option value="" selected></option>';
  foreach ($ctypes as $ctype => $cdata) {
    $output .= '<option value="' . $ctype .'">'. $cdata->name .'</option>';
  }
  $output .= '</select></div>';
		*/
		$output .= '<div class="nodeadmin-options"><form>'.drupal_render($form).'</form></div>';