menu_theme_switcher.module

<?php

	/**
	 * Implementation of hook_menu()
	 */
	function menu_theme_switcher_menu() {
		$items = array();
	
		$items['admin/build/themes/switch'] = array(
			'title' => 'Theme Switching',
			'description' => 'Allow active theme to be switched based on menu conditions.',
			'page callback' => 'drupal_get_form',
			'page arguments' => array('menu_theme_switcher_settings_form', NULL),
			'access arguments' => array('administer site configuration')
		);

		return $items;
	}

	/**
	 * Implementation of hook_init()
	 */
	function menu_theme_switcher_init(){		
		$item = menu_get_item(); 
	
		if(module_exists('menutrails')){
			$object = menu_get_object();
			if($object->nid && $object->path == substr(url($_GET['q']), 1)){
				$node_trails = variable_get('menutrails_node_types', array());
				$term_trails = variable_get('menutrails_terms', array());		
				if(!empty($node_trails[$object->type])){
					$item = menutrails_node_location($object);
				}
				if (!empty($object->taxonomy)) {
					foreach ($object->taxonomy as $term) {
						if (!empty($term_trails[$term->tid])) {
						  $item = menutrails_node_location($object);
						}
					}
				}
			}
		}

		menu_theme_switcher_check_active_conditions($item);
	}


	/**
	 * Implementation of preprocess_page().
	 */
	function menu_theme_switcher_preprocess_page(&$vars) {
		global $custom_theme;

		$vars['body_classes'] .= !empty($custom_theme) ? ' ' . $custom_theme : '';
	}

	/**
	 * Determine whether we need to switch themes	 
	 */
	function menu_theme_switcher_check_active_conditions($item){
		//
		// Check if our request is being done through ajax.
		// If so, just return -- otherwise the 'theme information' option
		// in views won't respect the proper templates
		//
		if (strtolower($_SERVER['HTTP_X_REQUESTED_WITH']) == 'xmlhttprequest' ) {
			return;
		}

		if ( !isset($item['href']) || !$item['href'] ) {			
			return false;
		}

		global $custom_theme;
	
		$theme_switcher_settings = variable_get('menu_theme_switcher_settings', null);

		$current_mlids = array();
		$current_plids = array();
	
		$get_menu_object = db_query('SELECT * FROM {menu_links} WHERE link_path = "%s"', $item['href']);
	
		while($menu_object = db_fetch_object($get_menu_object)){			
			$current_mlids[] = $menu_object->mlid;
			$current_plids = menu_theme_switcher_build_current_plids($menu_object);
		}

		if(!empty($theme_switcher_settings)){
			foreach($theme_switcher_settings as $idx => $settings){
				$menu_trigger = $settings['menu_trigger'];		
				$menu_triggers_parts = explode(':', $menu_trigger);		
		
				$menu_trigger_mlid = $menu_triggers_parts[1];	
		
				if(in_array($menu_trigger_mlid, $current_mlids) || ($settings['include_children'] && in_array($menu_trigger_mlid, $current_plids))){
					$custom_theme = $settings['theme_reaction'];
				}
			}
		}
		
		if( !empty($custom_theme) ){			
			init_theme();	
		}	
	}

	/**
	 * Iterate through the menu parent columns to find all of our relevant menu parents
	 * Used to determine which theme to display
	 */
	function menu_theme_switcher_build_current_plids($menu_object){
		$plids = array();
		$get_columns = db_query('SHOW columns FROM {menu_links} WHERE Field LIKE "p%"');
	
		while($column = db_fetch_object($get_columns)){
			$field_name = $column->Field;
			if(preg_match('/^p[0-9]+$/', $field_name)){
				if($menu_object->$field_name){
					$plids[] = $menu_object->$field_name;
				}
			}
		}
	
		return $plids;
	}
	
	/**
	 * Theme Switcher settings form
	 * @ingroup forms
	 * @see system_themes_form_submit()
	 */
	function menu_theme_switcher_settings_form(){
		$menu_options = array_merge(array('0' => 'None'), menu_parent_options(menu_get_menus(), 0));
		
		$active_themes = array( '0' => 'None' );
		foreach(list_themes() as $name => $theme){
			if($theme->status){
				$active_themes[$name] = $name;
			}
		}
		
		$theme_switcher_settings = variable_get('menu_theme_switcher_settings', null);
		
		$theme_settings_count = 1;
		if( isset($theme_switcher_settings) && !empty($theme_switcher_settings) ){
			$theme_settings_count += count($theme_switcher_settings);
		}
		
		for( $i = 0; $i < $theme_settings_count; $i++ ){
			$settings = $theme_switcher_settings[$i];
			
			$form['theme_switcher_settings_' . $i] = array(
				'#type' => 'fieldset',
				'#weight' => -($theme_settings_count - $i),
				'#title' => t('Theme Switcher Settings Group !theme_settings_count', array( '!theme_settings_count' => $i + 1)),
				'#collapsible' => FALSE
			);
		
			$form['theme_switcher_settings_' . $i]['menu_trigger_' . $i] = array(
				'#type' => 'select',
				'#options' => $menu_options,
				'#default_value' => $settings['menu_trigger'] ? $settings['menu_trigger'] : 0,
				'#title' => t('Menu Item Condition')				
			);			
		
			$form['theme_switcher_settings_' . $i]['include_children_' . $i] = array(
				'#type' => 'checkbox',
				'#default_value' => $settings['include_children'] ? $settings['include_children'] : 0,
				'#title' => t('Include children of this menu item?')
			);
		
			$form['theme_switcher_settings_' . $i]['theme_reaction_' . $i] = array(
				'#type' => 'select',
				'#options' => $active_themes,
				'#default_value' => $settings['theme_reaction'] ? $settings['theme_reaction'] : 0,
				'#title' => t('Active Theme Reaction')				
			);							
		}
		
		$form['theme_switcher_settings_count'] = array(
			'#type' => 'hidden',
			'#default_value' => $theme_settings_count
		);
		
		$form = system_settings_form($form);
	
		$form['#submit'][] = 'menu_theme_switcher_settings_form_submit';

		return $form;
	}

	/**
	 * Process theme switcher settings form submissions.
	 */
	function menu_theme_switcher_settings_form_submit($form, &$form_state) {
		$theme_switcher_settings = array();
		$idx = 0;

		for( $i = 0; $i < $form_state['values']['theme_switcher_settings_count']; $i++ ){
			if($form_state['values']['menu_trigger_' . $i]){
				$theme_switcher_settings[$idx]['menu_trigger'] = $form_state['values']['menu_trigger_' . $i];
				$theme_switcher_settings[$idx]['theme_reaction'] = $form_state['values']['theme_reaction_' . $i];

				if($form_state['values']['include_children_' . $i]){
					$theme_switcher_settings[$idx]['include_children'] = $form_state['values']['include_children_' . $i];
				}    		

				$idx++;			
			}
		}
			
		variable_set('menu_theme_switcher_settings', $theme_switcher_settings);    
	}