Add support for fof/merge-discussions

All the views will be moved to the target discussion when merging.

composer.json

@@ -6,6 +6,9 @@
     "flarum/core": "^1.0",
     "jaybizzle/crawler-detect": "^1.2"
   },
+  "require-dev": {
+    "fof/merge-discussions": "^1.0"
+  },
   "license": "MIT",
   "authors": [
     {
@@ -30,7 +33,10 @@
         "name": "far fa-eye",
         "backgroundColor": "#88CC23",
         "color": "#fff"
-      }
+      },
+      "optional-dependencies": [
+        "fof/merge-discussions"
+      ]
     },
     "flagrow": {
       "discuss": "https://discuss.flarum.org/d/26269"

extend.php

@@ -8,9 +8,10 @@
 use Flarum\Discussion\Event\Saving;
 use Flarum\Extend\ApiController;
 use Flarum\Extend\ApiSerializer;
+use Flarum\Extend\Conditional;
 use Flarum\Extend\Event;
+use FoF\MergeDiscussions\Events\MergingDiscussions;
 use Michaelbelgium\Discussionviews\Listeners;
-use Illuminate\Contracts\Events\Dispatcher;
 use Flarum\Extend\Locales;
 use Flarum\Extend\Frontend;
 use Flarum\Extend\Model;
@@ -81,4 +82,12 @@
 
     (new Event())
         ->listen(Saving::class, Listeners\SaveDiscussionFromModal::class),
-]; 
+
+    (new Conditional())
+        ->whenExtensionEnabled('fof-merge-discussions', function() {
+            return [
+                (new Event())
+                    ->listen(MergingDiscussions::class, Listeners\MergeDiscussionHandler::class),
+            ];
+        })
+];

src/Listeners/MergeDiscussionHandler.php

@@ -0,0 +1,22 @@
+<?php
+
+namespace Michaelbelgium\Discussionviews\Listeners;
+
+
+use Flarum\Discussion\Discussion;
+use FoF\MergeDiscussions\Events\MergingDiscussions;
+
+class MergeDiscussionHandler
+{
+    public function handle(MergingDiscussions $event)
+    {
+        $targetDiscussion = $event->discussion;
+
+        $targetDiscussion->increment('view_count', $event->mergedDiscussions->sum('view_count'));
+        $targetDiscussion->save();
+
+        $event->mergedDiscussions->each(function(Discussion $discussion) use ($targetDiscussion) {
+            $discussion->views()->update(['discussion_id' => $targetDiscussion->id]);
+        });
+    }
+}