subscriber-edit-comments.php

<?php
/**
 * Subscriber Edit Comments
 *
 * @package     SubscribersEditComments
 * @author      Bernhard Kau
 * @license     GPLv3
 *
 * @wordpress-plugin
 * Plugin Name: Subscriber Edit Comments
 * Description: This plugin allow users with the role "subscriber" to edit their own comments
 * Version: 1.0.0
 * Author: Bernhard Kau
 * Author URI: http://kau-boys.de
 * Plugin URI: https://gist.github.com/2ndkauboy/8d6eb6279e6ff395031c2ce77ded9f6f
 * License: GPLv3
 * License URI: http://www.gnu.org/licenses/gpl-3.0
 */

add_action( 'plugins_loaded', array( Subscriber_Edit_Comments::get_instance(), 'plugin_setup' ) );

/**
 * Class Subscriber_Edit_Comments
 */
class Subscriber_Edit_Comments {

	/**
	 * Plugin instance.
	 *
	 * @see   get_instance()
	 * @var  object
	 */
	protected static $instance = null;

	/**
	 * Access this plugin’s working instance
	 *
	 * @wp-hook plugins_loaded
	 * @return  object of this class
	 */
	public static function get_instance() {

		null === self::$instance and self::$instance = new self;

		return self::$instance;
	}

	/**
	 * Used for regular plugin work.
	 *
	 * @wp-hook  plugins_loaded
	 * @return   void
	 */
	public function plugin_setup() {
		add_action( 'admin_menu', array( $this, 'edit_comments_admin_menu' ) );
		add_filter( 'user_has_cap', array( $this, 'edit_comment_cap' ), 10, 4 );
		add_filter( 'map_meta_cap', array( $this, 'edit_comment_map_meta_cap' ), 10, 4 );
	}

	/**
	 * Constructor.
	 * Intentionally left empty and public.
	 *
	 * @see    plugin_setup()
	 */
	public function __construct() {
	}

	/**
	 * Overwriting the admin menu entry for the "edit_comments.php" page
	 *
	 * @todo: Remove this function when trac ticket #12104 is solved
	 * @see: https://core.trac.wordpress.org/ticket/12104
	 */
	public function edit_comments_admin_menu() {
		global $menu, $submenu;

		if ( current_user_can( 'moderate_comments' ) || current_user_can( 'edit_posts' ) ) {
			return;
		}

		$awaiting_mod = wp_count_comments();
		$awaiting_mod = $awaiting_mod->moderated;
		$menu[25] = array(
			sprintf( __( 'Comments %s' ), '<span class="awaiting-mod count-' . absint( $awaiting_mod ) . '"><span class="pending-count">' . number_format_i18n( $awaiting_mod ) . '</span></span>' ),
			'edit_comment',
			'edit-comments.php',
			'',
			'menu-top menu-icon-comments',
			'menu-comments',
			'dashicons-admin-comments',
		);
		$submenu['edit-comments.php'][0] = array( __( 'All Comments' ), 'edit_comment', 'edit-comments.php' );
	}

	/**
	 * Give users the "edit_posts" capability if they are on the "edit-comment.php" page
	 *
	 * @todo: Remove this function when trac ticket #12104 is solved
	 * @see: https://core.trac.wordpress.org/ticket/12104
	 *
	 * @param array   $allcaps An array of all the user's capabilities.
	 * @param array   $caps    Actual capabilities for meta capability.
	 * @param array   $args    Optional parameters passed to has_cap(), typically object ID.
	 * @param WP_User $user    The user object.
	 *
	 * @return mixed
	 */
	public function edit_comment_cap( $allcaps, $caps, $args, $user ) {
		if ( 'edit_posts' === $args[0] ) {
			global $pagenow;

			if ( 'edit-comments.php' === $pagenow ) {
				$allcaps['edit_posts'] = true;
			}
		}

		if ( 'edit_comment' === $args[0] ) {
			if ( $allcaps['moderate_comments'] ) {
				return $allcaps;
			}

			$comment = get_comment( $args[2] );
			$current_user = wp_get_current_user();

			if ( $current_user->user_login === $comment->comment_author ) {
				$allcaps['edit_comment'] = true;
			}
		}

		return $allcaps;
	}

	/**
	 * Map the meta caps for "edit_comments"
	 *
	 * @param array  $caps    Returns the user's actual capabilities.
	 * @param string $cap     Capability name.
	 * @param int    $user_id The user ID.
	 * @param array  $args    Adds the context to the cap. Typically the object ID.
	 *
	 * @return array
	 */
	public function edit_comment_map_meta_cap( $caps, $cap, $user_id, $args ) {
		if ( 'edit_comment' === $cap ) {
			$comment = get_comment( $args[2] );
			$current_user = wp_get_current_user();

			if ( $current_user->user_login === $comment->comment_author ) {
				$caps = array( 'edit_comment' );
			}
		}

		return $caps;
	}
}