<?php

/*
Name:        Admin Notice Helper
URI:         https://github.com/iandunn/admin-notice-helper
Version:     0.2
Author:      Ian Dunn
Author URI:  http://iandunn.name
License:     GPLv2
*/

/*  
 * Copyright 2014 Ian Dunn (email : ian@iandunn.name)
 * 
 * Notices are saved in SESSION (in original it saves in database, but i this it not needed)
 */

if (!defined('ABSPATH')) {
    die('Access denied.');
}

if (!class_exists('FV_Admin_Notice_Helper')) {

    class FV_Admin_Notice_Helper
    {
        // Declare variables and constants
        protected static $instance;
        protected $notices, $notices_were_updated;

        /**
         * Constructor
         */
        protected function __construct()
        {
            //add_action( 'init',          array( $this, 'init' ), 9 );         // needs to run before other plugin's init callbacks so that they can enqueue messages in their init callbacks
            /*if (session_id() == '') {
                session_start();
            }*/
            if ( is_admin() )
            {
                add_action('admin_notices', array($this, 'print_notices'));
                add_action('fv_admin_notices', array($this, 'print_notices'));
            }
            add_action('shutdown', array($this, 'shutdown'));
        }

        /**
         * Provides access to a single instances of the class using the singleton pattern
         *
         * @mvc    Controller
         * @author Ian Dunn <ian@iandunn.name>
         * @return object
         */
        public static function get_singleton()
        {
            if (!isset(self::$instance)) {
                self::$instance = new FV_Admin_Notice_Helper();

                $notices = get_option( 'fv_notices', array() );

                if ( empty($notices) ) {
                    $notices = array();
                }

                self::$instance->notices = $notices;

                self::$instance->notices_were_updated = false;
            }

            return self::$instance;
        }

        /**
         * Initializes variables
         */
        public function init()
        {
            //$default_notices             = array( 'default' => array(), 'error' => array() );
        }

        /**
         * Queues up a message to be displayed to the user
         *
         * @param string $message The text to show the user
         * @param string $type 'update' for a success or notification message, or 'error' for an error message
         * 'default', 'info', 'danger', 'success', 'primary', 'warning'
         *
         */
        public function enqueue($message, $type = 'default')
        {
            /*
            if ( isset( $this->notices[ $type ] ) &&  in_array( $message, array_values( $this->notices[ $type ] ) ) ) {
                return;
            }
            */
            if ( !isset($this->notices[$type]) ) {
                $this->notices[$type] = array();
            }
            if (!empty($type) && !isset($this->notices[$type][crc32($message)])) {
                $this->notices[$type][crc32($message)] = (string)$message;
                $this->notices_were_updated = true;
            }
        }

        /**
         * Displays updates and errors
         */
        public function print_notices()
        {

            foreach (array('default', 'info', 'danger', 'success', 'primary', 'warning') as $type) {
                if (isset($this->notices[$type]) && count($this->notices[$type])) {

                    require('views/admin-notice.php');

                    $this->notices[$type] = array();
                    $this->notices_were_updated = true;
                }
            }
        }

        /**
         * Writes notices to the database
         */
        public function shutdown()
        {
            //var_dump( $this->notices_were_updated );
            if ($this->notices_were_updated) {
                //$_SESSION['user_notices'] = $this->notices;
                update_option( 'fv_notices', $this->notices );
            }
        }
    } // end Admin_Notice_Helper

    FV_Admin_Notice_Helper::get_singleton(); // Create the instance immediately to make sure hook callbacks are registered in time

    if (!function_exists('wp_add_notice')) {
        /**
         * Queues up a message to be displayed to the user
         *
         * @param string $message The text to show the user
         * @param string $type 'update' for a success or notification message, or 'error' for an error message
         * 'default', 'info', 'danger', 'success', 'primary', 'warning'
         *
         */
        function wp_add_notice($message, $type = 'default')
        {
            FV_Admin_Notice_Helper::get_singleton()->enqueue($message, $type);
        }
    }
}