related.php

<?php
/*
Plugin Name: Related
Plugin URI: http://products.zenoweb.nl/free-wordpress-plugins/related/
Description: A simple 'related posts' plugin that lets you select related posts manually.
Version: 1.6.4
Author: Marcel Pol
Author URI: http://zenoweb.nl
Text Domain: related
Domain Path: /lang/


Copyright 2010-2012  Matthias Siegel  (email: matthias.siegel@gmail.com)
Copyright 2013-2015  Marcel Pol       (email: marcel@timelord.nl)

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.

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.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
*/



if (!class_exists('Related')) :
	class Related {

		/*
		 * __construct
		 * Constructor
		 */
		public function __construct() {

			// Set some helpful constants
			$this->defineConstants();

			// Register hook to save the related posts when saving the post
			add_action('save_post', array(&$this, 'save'));

			// Start the plugin
			add_action('admin_menu', array(&$this, 'start'));

			// Add the related posts to the content, if set in options
			add_filter( 'the_content', array($this, 'related_content_filter') );
		}


		/*
		 * defineConstants
		 * Defines a few static helper values we might need
		 */
		protected function defineConstants() {
			define('RELATED_VERSION', '1.6.4');
			define('RELATED_HOME', 'http://zenoweb.nl');
			define('RELATED_FILE', plugin_basename(dirname(__FILE__)));
			define('RELATED_ABSPATH', str_replace('\\', '/', WP_PLUGIN_DIR . '/' . plugin_basename(dirname(__FILE__))));
			define('RELATED_URLPATH', WP_PLUGIN_URL . '/' . plugin_basename(dirname(__FILE__)));
		}


		/*
		 * start
		 * Main function
		 */
		public function start() {

			// Load the scripts
			add_action('admin_enqueue_scripts', array(&$this, 'loadScripts'));

			// Load the CSS
			add_action('admin_enqueue_scripts', array(&$this, 'loadCSS'));

			// Adds a meta box for related posts to the edit screen of each post type in WordPress
			$related_show = get_option('related_show');
			$related_show = json_decode( $related_show );
			if ( empty( $related_show ) ) {
				$related_show = array();
				$related_show[] = 'any';
			}
			if ( in_array( 'any', $related_show ) ) {
				foreach (get_post_types() as $post_type) :
					add_meta_box($post_type . '-related-posts-box', __('Related posts', 'related' ), array(&$this, 'displayMetaBox'), $post_type, 'normal', 'high');
				endforeach;
			} else {
				foreach ($related_show as $post_type) :
					add_meta_box($post_type . '-related-posts-box', __('Related posts', 'related' ), array(&$this, 'displayMetaBox'), $post_type, 'normal', 'high');
				endforeach;
			}

		}


		/*
		 * loadScripts
		 * Load Javascript
		 */
		public function loadScripts() {
			wp_enqueue_script('jquery-ui-core');
			wp_enqueue_script('jquery-ui-sortable');
			wp_enqueue_script('related-scripts', RELATED_URLPATH .'/scripts.js', false, RELATED_VERSION, true);
		}


		/*
		 * loadCSS
		 * Load CSS
		 */
		public function loadCSS() {
			wp_enqueue_style('related-css', RELATED_URLPATH .'/styles.css', false, RELATED_VERSION, 'all');
		}


		/*
		 * save
		 * Save related posts when saving the post
		 */
		public function save($id) {
			global $pagenow;

			if (defined('DOING_AUTOSAVE') && DOING_AUTOSAVE) return;

			if ( isset($_POST['related-posts']) ) {
				update_post_meta($id, 'related_posts', $_POST['related-posts']);
			}
			/* Only delete on post.php page, not on Quick Edit. */
			if ( empty($_POST['related-posts']) ) {
				if ( $pagenow == 'post.php' ) {
					delete_post_meta($id, 'related_posts');
				}
			}
		}


		/*
		 * displayMetaBox
		 * Creates the output on the post screen
		 */
		public function displayMetaBox() {
			global $post;

			$post_id = $post->ID;

			echo '<p>' . __('Choose related posts. You can drag-and-drop them into the desired order:', 'related' ) . '</p><div id="related-posts">';

			// Get related posts if existing
			$related = get_post_meta($post_id, 'related_posts', true);

			if (!empty($related)) :
				foreach($related as $r) :
					$p = get_post($r);


					echo '
						<div class="related-post" id="related-post-' . $r . '">


							<input type="hidden" name="related-posts[]" value="' . $r . '">
							<span class="related-post-title">' . $p->post_title . ' (' . ucfirst(get_post_type($p->ID)) . ')</span>
							<a href="#">' . __('Delete', 'related' ) . '</a>
						</div>';
				endforeach;
			endif;

			/* First option should be empty with a data placeholder for text.
			 * The jQuery call allow_single_deselect makes it possible to empty the selection
			 */
			echo '
				</div>
				<p>
					<select class="related-posts-select" name="related-posts-select" data-placeholder="' . __('Choose a related post... ', 'related' ) . '">';

			echo '<option value="0"></option>';


			$related_list = get_option('related_list');
			$related_list = json_decode( $related_list );

			if ( empty( $related_list ) ) {
				$related_list = array();
				$related_list[] = 'any';
			}


			/*
			 * If in Settings 'any' is set it will just list the options in the select-box.
			 * If specific posttypes are set, it will show each posttype in an optgroup in the select-box.
			 * Also fetch attachments by setting post_status to 'inherit' as well.
			 */

			if ( in_array( 'any', $related_list ) ) {

				$query = array(
					'nopaging' => true,
					'post__not_in' => array($post_id),
					'post_status' => 'publish, inherit',
					'posts_per_page' => -1,
					'post_type' => array( 'post', 'page' ),
					'orderby' => 'title',
					'order' => 'ASC'
				);
				$p = new WP_Query($query);

				foreach ($p->posts as $thePost) {
					?>
					<option value="<?php echo $thePost->ID; ?>">
						<?php echo $thePost->post_title . ' (' . ucfirst(get_post_type($thePost->ID)) . ')'; ?>
					</option>
					<?php
				}

			} else {

				foreach ( $related_list as $post_type ) {

					$query = array(
						'nopaging' => true,
						'post__not_in' => array($post_id),
						'post_status' => 'publish, inherit',
						'posts_per_page' => -1,
						'post_type' => $post_type,
						'orderby' => 'title',
						'order' => 'ASC'
					);
					$p = new WP_Query($query);

					echo '<optgroup label="'. $post_type .'">';

						foreach ($p->posts as $thePost) {
							?>
							<option value="<?php echo $thePost->ID; ?>">
								<?php echo  $thePost->post_title; ?>
							</option>
							<?php
						}

					echo '</optgroup>';

				}

			}
			wp_reset_query();
			wp_reset_postdata();

			echo '
					</select>
				</p>';

		}


		/*
		 * show
		 * The frontend function that is used to display the related post list
		 */
		public function show( $id, $return = false ) {

			global $wpdb;

			/* Compatibility for Qtranslate, Qtranslate-X and MQtranslate, and the get_permalink function */
			$plugin = "qtranslate/qtranslate.php";
			$q_plugin = "qtranslate-x/qtranslate.php";
			$m_plugin = "mqtranslate/mqtranslate.php";
			include_once( ABSPATH . 'wp-admin/includes/plugin.php' );
			if ( is_plugin_active($plugin) || is_plugin_active($q_plugin) || is_plugin_active($m_plugin) ) {
				add_filter('post_type_link', 'qtrans_convertURL');
			}

			if (!empty($id) && is_numeric($id)) :
				$related = get_post_meta($id, 'related_posts', true);

				if (!empty($related)) :
					$rel = array();
					foreach ($related as $r) :
						$p = get_post($r);
						$rel[] = $p;
					endforeach;

					// If value should be returned as array, return it
					if ($return) :
						return $rel;

					// Otherwise return a formatted list
					else :
						if ( is_array( $rel ) && count( $rel ) > 0 ) {
							$list = '<ul class="related-posts large-block-grid-3 medium-block-grid-3 small-block-grid-1">';
							foreach ($rel as $r) :
								if ( is_object( $r ) ) {
									if ( $r->post_status != 'trash' ) {
										$list .= '<li>';
										//$list .= '<a href="' . get_permalink($r->ID) . '">' . get_the_title($r->ID) . '</a>';
											$large_image_url = wp_get_attachment_image_src( get_post_thumbnail_id( $r->ID ), 'medium');
											$list .= '<a href="' . get_permalink($r->ID) . '" title="' . esc_attr( get_the_title( $r->ID ) ) . '" rel="bookmark">';
												$list .= '<div class="related-image" style="background-image:url(\'' . $large_image_url[0] . '\');">';
													$list .= '<div class="related-thumbnail">';
													$list .= '</div>';			
													$list .= '<h5 class="entry-title"><a href="' . get_permalink($r->ID) . '" title="' . esc_attr( get_the_title( $r->ID ) ) . '" rel="bookmark">' . get_the_title( $r->ID ) . '</a></h5>';
													$list .= '</a>';
												$list .= '</div>';
											$list .= '</a>';
										$list .= '</li>';
									}
								}
							endforeach;
							$list .= '</ul>';

							return $list;
						}
					endif;
				else :
					return false;
				endif;
			else :
				return __('Invalid post ID specified', 'related' );
			endif;
		}


		/*
		 * Add the plugin data to the content, if it is set in the options.
		 */
		public function related_content_filter( $content ) {
			if ( get_option( 'related_content', 0 ) == 1 && is_single() ) {
				global $related;
				$related_posts = $related->show( get_the_ID() );
				if ( $related_posts ) {
					$content .= '<div class="related_content" style="clear:both;">';
					$content .= '<h3 class="widget-title">';
					$content .= get_option('related_content_title', __('Related Posts', 'related'));
					$content .= '</h3>';
					$content .= $related_posts;
					$content .= "</div>";
				}
			}
			// otherwise returns the old content
			return $content;
		}

	}

endif;


/*
 * related_links
 * Add Settings link to the main plugin page
 *
 */

function related_links( $links, $file ) {
	if ( $file == plugin_basename( dirname(__FILE__).'/related.php' ) ) {
		$links[] = '<a href="' . admin_url( 'options-general.php?page=related.php' ) . '">'.__( 'Settings', 'related' ).'</a>';
	}
	return $links;
}
add_filter( 'plugin_action_links', 'related_links', 10, 2 );


/* Include Settings page */
include( 'page-related.php' );

/* Include widget */
include( 'related-widget.php' );


/*
 * related_init
 * Function called at initialisation.
 * - Loads language files
 * - Make an instance of Related()
 */

function related_init() {
	load_plugin_textdomain('related', false, dirname( plugin_basename( __FILE__ ) ) . '/lang/');

	// Start the plugin
	global $related;
	$related = new Related();
}
add_action('plugins_loaded', 'related_init');