help-class.php

<?php
/**
 * @author		Conner McCall
 * @copyright	Copyright (c) 2011, Conner McCall, http://connermccall.com
 * @license		http://en.wikipedia.org/wiki/MIT_License The MIT License
 * @package		wp-help
 * @version		0.1
 * @link		https://github.com/sloped/Wordpress-Help
 */

class wp_help {

	/**
	 * Set default post labels used when creating the new post
	 * type for the help. 
	 *
	 * @since	0.1
	 * @access	public
	 * @var		array 
	 */
	var $post_labels = array ('name' => 'Help',
							  'singular_name' => 'Help',
							  'menu_name' => 'Help',
							  'add_new' => 'Add Help',
							  'add_new_item' => 'Add New Help',
							  'edit' => 'Edit Help',
							  'edit_item' => 'Edit Help',
							  'new_item' => 'New Help',
							  'view' => 'View Help',
							  'view_item' => 'View Help',
							  'search_items' => 'Search Help',
							  'not_found' => 'No Help Found',
							  'not_found_in_trash' => 'No Help Found in Trash',
							);
	/**
	 * Set default post type used for the help pages
	 *
	 * @since	0.1
	 * @access	public
	 * @var		string 
	 */
	var $post_pages = 'help';
	/**
	 * Set default name for the post type used for the help pages
	 *
	 * @since	0.1
	 * @access	public
	 * @var		string 
	 */
	var $post_name = 'Help';
	/**
	 * Sets the default capability type used to control access to the help pages
	 *
	 * @since	0.1
	 * @access	public
	 * @var		string 
	 */
	var $capability_type = 'post';
	/**
	 * Used to set the post type the metabox and contextual help are displayed on
	 *
	 * @since	0.1
	 * @access	public
	 * @var		string 
	 */
	var $post_type;
	/**
	 * Used to set the title of the page containing the actual help
	 *
	 * @since	0.1
	 * @access	public
	 * @var		string 
	 */
	var $help_page_name;
	/**
	 * Controls whether or not the help is displayed as a metabox
	 *
	 * @since	0.1
	 * @access	public
	 * @var		bool 
	 */
	var $on_edit_screen = true;
	/**
	 * Controls whether or not the help is displayed as contexual help
	 *
	 * @since	0.1
	 * @access	public
	 * @var		bool 
	 */
	var $in_contextual = true;
	/**
	 * Used to initialize the post content. 
	 *
	 * @since	0.1
	 * @access	public
	 * @var		bool 
	 */
	var $page_content = false;
	
	/**
	 * Constructor
	 * 
	 * @since	0.1
	 * @access	public
	 * @param	array[string]string
	 */
	function __construct($args = array()) {
		if(is_array($args)) {
			if(array_key_exists('post_pages',$args)) $this->post_pages = $args['post_pages'];
			if(array_key_exists('labels',$args)) $this->post_labels = $args['labels'];
		}
		add_action('init', array($this, '_create_post_type'));
	}
	/**
	 * Used to create help pages and place on the appropriate post types
	 * 
	 * @since	0.1
	 * @access	public
	 * @param	array[string]string
	 */
	public function create_help($args) {
		if(is_array($args)) {
			if(array_key_exists('post_type',$args)) $this->post_type = $args['post_type'];
			else die('You must pass a post type to display help on');
			if(array_key_exists('page_title', $args)) $this->help_page_title = $args['page_title'];
			else die('You must pass a title for you help page');
			if(array_key_exists('page_content', $args)) $this->page_content = $args['page_content'];

		}
		add_action('init',array($this, 'create_help_page'));
		add_action('add_meta_boxes', array($this, 'add_meta_boxes') , 10,2);
	}
	/**
	 * Creates the post type for help pages if it does not exist. 
	 * 
	 * @since	0.1
	 * @access	private
	 * 
	 */
	function _create_post_type() {
	
		if(!post_type_exists($this->post_pages) ) {
		register_post_type($this->post_pages, 
			array(	'label' => $this->post_name,
			'description' => 'Post type for user editable help',
			'public' => false,
			'show_ui' => true,
			'show_in_menu' => true,
			'capability_type' => $this->capability_type,
			'hierarchical' => false,
			'query_var' => true,
			'has_archive' => false
			,'supports' => array('editor',),
			'menu_position' => 12,
			'labels' => $this->post_labels,) );
		}
	}
	
	/**
	 * Creates the metabox and contextual tab for the help
	 * 
	 * @since	0.1
	 * @access	private
	 * 
	 * see get_contents()
	 */
	function add_meta_boxes($post_type , $post) {
		if($this->on_edit_screen) {
			add_meta_box(
				$this->post_type . '_help', // id of the <div> we'll add
				'Help', //title
				array($this, 'help_box_contents'), // callback function that will echo the box content
				$this->post_type // where to add the box: on "post", "page", or "link" page
			);
		}
		if($this->in_contextual) {
			if ( $this->post_type == $post_type ) {
				get_current_screen()->add_help_tab( array(
					'id'      => 'page-help-id',
					'title'   => __( 'Help' ),
					'content' =>	$this->get_contents(),
					) 
				);
			}
		}
	}
	/**
	 * Queries the Wordpress Database for the page containing the help. Formating done via wpautop
	 * 
	 * @since	0.1
	 * @access	private
	 * 
	 */
	private function get_contents() {
		$help = new WP_query();
		$args['name'] = $this->help_page_name;
		$args['post_type'] = $this->post_pages;
		$help->query( $args );
		if($help->post_count > 0) {
		foreach( $help->posts as $post ) : setup_postdata($post); ?>
		<?php return wpautop($post->post_content);?>
		<?php endforeach;
		}
	}
	/**
	 * Outputs the help page contents into the metabox
	 * 
	 * @since	0.1
	 * @access	private
	 * 
	 */
	function help_box_contents() {
	?>
	  <div class="custom_dashboard">
			<?php echo $this->get_contents();?>
		</div>
		<?php
	}
	/**
	 * Creates the help page for the help being created. Does not duplicate pages. 
	 * 
	 * @since	0.1
	 * @access	private
	 * 
	 */
	function create_help_page() {
		if($this->wp_exist_post($this->post_type . '_wp_help') == '') {
			$post = array(
			  'comment_status' => 'closed', // 'closed' means no comments.
			  'ping_status' =>  'closed', // 'closed' means pingbacks or trackbacks turned off
			  'post_author' => 1, //The user ID number of the author.
			  'post_name' => $this->post_type . '_wp_help', // The name (slug) for your post
			  'post_status' => 'publish', //Set the status of the new post. 
			  'post_title' => $this->help_page_title, //The title of your post.
			  'post_type' => $this->post_pages,
			  );
			if($this->page_content) $post['page_content'] = $this->page_content;
			$this->page_content = false;
			wp_insert_post( $post, true );
		}
	}
	/**
	 * Helper function to determine if a page exists with the given name. 
	 * 
	 * @since	0.1
	 * @access	private
	 * 
	 */
	private function wp_exist_post($slug) {
		global $wpdb;
		return $wpdb->get_row("SELECT ID FROM wp_posts WHERE post_name = '" . $slug . "'", 'ARRAY_A');
	}
}