From a803d2441bc61d9893c1803f4add34079cdb6d1b Mon Sep 17 00:00:00 2001
From: saint <saint@saint.li>
Date: Sat, 7 Sep 2024 00:51:22 +1000
Subject: [PATCH] v0.4 Huge re-write... hoping it may work... added debug
 output

---
 plugin.rb | 88 +++++++++++++++++++++++++++++++++++++++++++------------
 1 file changed, 69 insertions(+), 19 deletions(-)

diff --git a/plugin.rb b/plugin.rb
index 4aa7281..7fedf57 100644
--- a/plugin.rb
+++ b/plugin.rb
@@ -4,7 +4,7 @@
 
 # name: discourse-legacy_links
 # about: A plugin to handle legacy Gossamer Forums URLs
-# version: 0.2
+# version: 0.4
 # authors: saint@federated.computer
 # url: https://gitea.federated.computer/saint/discourse-legacy_links.git
 
@@ -14,62 +14,112 @@
 
 # after_initialize do
 after_initialize do
-  module ::DiscourseCustomRouting
+  module ::DiscourseLegacyLinks
     class Engine < ::Rails::Engine
-      engine_name "discourse_custom_routing"
-      isolate_namespace DiscourseCustomRouting
+      engine_name "discourse_legacy_links"
+      isolate_namespace DiscourseLegacyLinks
     end
 
     # Define the custom controller
     class CustomPostController < ::ApplicationController
       # Match URLs that include a post_id at the end or query parameter
+      # Main action triggered when the route is matched.
       def index
         post_id = extract_post_id_from_request
 
         if post_id
+          logger.info "[DEBUG] Processing request for post_id: #{post_id}"
           post = find_post_by_custom_field(post_id)
           
           if post
             # Redirect to the post URL if found
+            logger.info "[DEBUG] Redirecting to post with ID: #{post.id}"
             redirect_to post_url(post)
           else
             # Return 404 if the post is not found
+            logger.error "[ERROR] Post with original_gossamer_id #{post_id} not found"
             render plain: 'Post not found', status: 404
           end
         else
           # Handle cases where the post_id cannot be extracted
+          logger.error "[ERROR] Could not extract post_id from the request"
           render plain: 'Invalid URL', status: 400
         end
       end
 
       private
 
+      # Extracts the post ID from the request URL or query string.
+      # Supports various formats of legacy forum URLs.
+      # @return [Integer, nil] The extracted post ID or nil if not found
       def extract_post_id_from_request
-        # Extract post_id from various URL formats
+        # Check if post_id is passed as a query parameter (?post=post_id)
         if params[:post_id]
-          params[:post_id].to_i
-        elsif request.path.match(%r{/forum/[^/]+/P(\d+)/})
-          $1.to_i
-        elsif request.query_string.match(/post=(\d+)/)
-          $1.to_i
-        elsif request.query_string.match(/parent_post_id=(\d+)/)
-          $1.to_i
-        else
-          nil
+          post_id = params[:post_id].to_i
+          logger.info "[DEBUG] Extracted post_id from query param: #{post_id}"
+          return post_id
         end
+
+        # Check for post_id in the URL path (e.g., /forum/.../P12345/)
+        if match = request.path.match(%r{/forum/[^/]+/P(\d+)/?})
+          post_id = match[1].to_i
+          logger.info "[DEBUG] Extracted post_id from URL path: #{post_id}"
+          return post_id
+        end
+
+        # Check for post_id in the query string (e.g., ?post=12345)
+        if match = request.query_string.match(/post=(\d+)/)
+          post_id = match[1].to_i
+          logger.info "[DEBUG] Extracted post_id from query string (?post=): #{post_id}"
+          return post_id
+        end
+
+        # Check for parent_post_id in the query string (e.g., ?parent_post_id=12345)
+        if match = request.query_string.match(/parent_post_id=(\d+)/)
+          post_id = match[1].to_i
+          logger.info "[DEBUG] Extracted parent_post_id from query string: #{post_id}"
+          return post_id
+        end
+
+        # If no post_id was found in any format
+        logger.warn "[DEBUG] Could not extract post_id from request"
+        nil
       end
 
+      # Finds the Discourse post that has the specified custom field value.
+      # The custom field used is 'original_gossamer_id'.
+      # @param post_id [Integer] The extracted Gossamer forum post ID
+      # @return [Post, nil] The corresponding Discourse post or nil if not found
       def find_post_by_custom_field(post_id)
-        # Find the post with the specified custom field
-        Post.joins(:topic_custom_fields)
-            .where(topic_custom_fields: { name: 'original_gossamer_id', value: post_id.to_s })
-            .first
+        logger.info "[DEBUG] Searching for post with custom field 'original_gossamer_id' and value #{post_id}"
+
+        # Use ActiveRecord query to find the post by the custom field value
+        post = Post.joins(:topic_custom_fields)
+                   .where(topic_custom_fields: { name: 'original_gossamer_id', value: post_id.to_s })
+                   .first
+
+        if post
+          logger.info "[DEBUG] Found post with ID: #{post.id} for original_gossamer_id: #{post_id}"
+        else
+          logger.warn "[DEBUG] No post found for original_gossamer_id: #{post_id}"
+        end
+
+        post
+      end
+
+      # Redirects to the specified Discourse post.
+      # @param post [Post] The Discourse post to redirect to
+      def redirect_to_post(post)
+        topic_url = "#{Discourse.base_url}/t/#{post.topic_id}/#{post.post_number}"
+        logger.info "[DEBUG] Redirecting to topic URL: #{topic_url}"
+        redirect topic_url
       end
     end
 
-    # Register custom routes
+    # Register custom routes to handle legacy URLs
     Discourse::Application.routes.append do
       get '/forum/*path' => 'custom_post#index'
     end
   end
 end
+