[Integration] WordPress Posts Re-posted to punBB Forum

/**
 * Name: WordPress Posts Re-posted to punBB Forum
 * Requirements: WordPress 3.9+, punBB 1.4.2+
 * Instructions: 1. Edit config to match your punBB install and preferred user. 2. Add this code to your WordPress theme's functions.php file. 3. Publish a post on WordPress and see it auto-publish to your punBB.
 * Version: 1.0
 * Author: FWD:labs, based on code by Jones at punbb.informer.com/forums/topic/23056/wordpress2punbb-posting/
 * Author URI: http://fwdlabs.com/resources/code/
 * License: GPL2
 */

function punbb_publish_post($post_ID) {
        
    global $wpdb;
    
    // Config
    $punbbPrefix = ""; // Example: punbb_
    $punbbUsername = ""; // Example: Forum Admin
    $punbbUserID = ""; // Example: 2
    $punbbUserIP = ""; // Example: 1.2.3.4
    $punbbForumID = ""; // Example: 8
    
    // Exit gracefully if config unchanged
    if ($punbbPrefix == "" || $punbbUsername == "" || $punbbUserID == "" || $punbbUserIP == "" || $punbbForumID == "") {
        return false;
    }
    
    // Select WordPress post based on the provided $post_ID
    $wppost = $wpdb->get_row("SELECT ID, post_date, post_title, post_content FROM ".$wpdb->posts." WHERE ID = ".mysql_real_escape_string(trim($post_ID))." LIMIT 1");
        
    $getArticle = $wppost->post_content;

    // Convert HTML to BBCode
    
        // Images need some extra help to get to BBCode
        
        // If WordPress formatted the image
        // $getArticle = preg_replace("/<img src=([^>]+) alt=([^>]+) width=([^>]+) height=([^>]+) class=([^>]+)\>/i", '[img]$1[/img]', $getArticle);

        // If a content editor formatted the image by hand
        // $getArticle = preg_replace("/<img src=([^>]+) \/\>/i", '[img]$1[/img]', $getArticle);

        $getArticle = preg_replace('#<img.+?src=[\'"]([^\'"]+)[\'"].*?>#i', '[img]$1[/img]', $getArticle);    
                
        // Remove <br style="clear:both;/">, which may break the input
        $getArticle = preg_replace("/<br style=([^>]+)\>/i", "\n", $getArticle);
        
        // Remove [caption] content
        // Source: stackoverflow.com/a/16988328/1527619
        $getArticle = preg_replace('#\s*\[caption[^]]*\].*?\[/caption\]\s*#is', '', $getArticle);
    
        // Convert HTML to punBB'd BBCODE
        // Improvements made for list items and double quotes
        // Based upon bb2html() by Louai Munajim
        $htmlcode = array("&lt;", "&gt;",
            "<ul>", "</ul>", 
            "<li>", "</li>", 
            "<strong>", "</strong>", 
            "<u>", "</u>", 
            "<i>", "</i>",
            "<em>", "</em>",
            '<a href="', "</a>",
            "<blockquote>", "</blockquote>",
            '">',
            '"');
        $bbcode = array("<", ">",
            "[list]", "[/list]", 
            "[*]", "[/*]",
            "[b]", "[/b]", 
            "[u]", "[/u]", 
            "[i]", "[/i]",
            "[i]", "[/i]",
            '[url="', "[/url]",
            "[quote]", "[/quote]",
            '"]',
            '');

    $getArticle = str_replace($htmlcode, $bbcode, $getArticle);
                
    // Check punBB if we're editing a topic or adding a new topic, simply based on the username and post date matching
    $wppost_check = $wpdb->get_row("SELECT id, topic_id FROM ".$punbbPrefix."posts WHERE poster = '".$punbbUsername."' AND posted = ".strtotime($wppost->post_date));
    
    // punBB found a match, so we're editing an existing topic
    if ($wppost_check) {

        // Update the title of the punBB topic with any changes made within WordPress
         $wpdb->query("UPDATE ".$punbbPrefix."topics SET subject = '".mysql_real_escape_string(trim($wppost->post_title))."' WHERE id = ".$wppost_check->topic_id);
        
        // Update the content of the punBB post with any changes made within WordPress
        $wpdb->query("UPDATE ".$punbbPrefix."posts SET message = '".mysql_real_escape_string(trim($getArticle))."' WHERE id = ".$wppost_check->id);

    // punBB did not find a match, so we're adding a new topic
    } else {
        
        // Add a permalink to the original post in WordPress to the punBB message board re-post
        $permalink = get_permalink($post_ID);
        $wp_add = "\n\nView the original post [url=$permalink]here[/url]";
        $displayArticle = $getArticle.$wp_add;
        
        // Modify the title of the punBB version, perhaps with a prefix like [NEWS]
        $displayTopicTitle = $wppost->post_title;
        $displayTopicTitle = "[NEWS] ".$displayTopicTitle;
        
        // Create the punBB topic
        $wpdb->query("INSERT INTO ".$punbbPrefix."topics (poster, subject, posted, last_post, last_poster, forum_id) VALUES(
            '".$punbbUsername."',
            '".$displayTopicTitle."',
            ".strtotime($wppost->post_date).",
            ".strtotime($wppost->post_date).",
            '".$punbbUsername."',
            '".$punbbForumID."'
            )");
        $topic_id = $wpdb->insert_id;

        // Create the punBB post in the new topic
        $wpdb->query("INSERT INTO ".$punbbPrefix."posts (poster, poster_id, message, posted, topic_id, poster_ip) VALUES(
            '".$punbbUsername."',
            ".$punbbUserID.",
            '".mysql_real_escape_string(trim($displayArticle))."',
            ".strtotime($wppost->post_date).",
            ".$topic_id.",
            '".$punbbUserIP."'
            )");
        $post_id = $wpdb->insert_id;

        // New topic in punBB needs first_post_id and last_post_id to successfully set
        $wpdb->query("UPDATE ".$punbbPrefix."topics SET last_post_id = ".$post_id.", first_post_id = ".$post_id." WHERE id = ".$topic_id);
        
        // Update the forums table with last post, last post ID, and last poster, which emulates how posts are done within punBB
        $wpdb->query("UPDATE ".$punbbPrefix."forums SET last_post = ".strtotime($wppost->post_date).", last_post_id = ".$post_id.", last_poster = '".$punbbUsername."' WHERE id = $punbbForumID");
        
        // Get the number of posts of the user
        $punbb_postnumber = $wpdb->get_row("SELECT num_posts FROM ".$punbbPrefix."users WHERE username = '".$punbbUsername."' LIMIT 1");
        
        // Add one to the number of their posts
        $wpdb->query("UPDATE ".$punbbPrefix."users SET num_posts = ".$punbb_postnumber->num_posts."+1 WHERE username = '".$punbbUsername."'");
        
    }

    return $post_ID;

}

add_action( 'publish_post', 'punbb_publish_post' );