From 0a078adab3baa1d8f2512a9a286fc547489cb2b2 Mon Sep 17 00:00:00 2001
From: Peter Deltchev <peter@deltchev.com>
Date: Wed, 6 Jan 2016 05:33:23 -0800
Subject: [PATCH] #20: Genre tags in files are now updated when a genre is
 renamed.

---
 app/Commands/RenameGenreCommand.php    |  6 ++
 app/Jobs/UpdateTagsForRenamedGenre.php | 97 ++++++++++++++++++++++++++
 2 files changed, 103 insertions(+)
 create mode 100644 app/Jobs/UpdateTagsForRenamedGenre.php

diff --git a/app/Commands/RenameGenreCommand.php b/app/Commands/RenameGenreCommand.php
index 46d2f53a..bb71aa9b 100644
--- a/app/Commands/RenameGenreCommand.php
+++ b/app/Commands/RenameGenreCommand.php
@@ -21,12 +21,16 @@
 namespace Poniverse\Ponyfm\Commands;
 
 use Gate;
+use Illuminate\Foundation\Bus\DispatchesJobs;
 use Illuminate\Support\Str;
+use Poniverse\Ponyfm\Jobs\UpdateTagsForRenamedGenre;
 use Poniverse\Ponyfm\Models\Genre;
 use Validator;
 
 class RenameGenreCommand extends CommandBase
 {
+    use DispatchesJobs;
+
     /** @var Genre */
     private $_genre;
     private $_newName;
@@ -72,6 +76,8 @@ class RenameGenreCommand extends CommandBase
         $this->_genre->slug = $slug;
         $this->_genre->save();
 
+        $this->dispatch(new UpdateTagsForRenamedGenre($this->_genre));
+
         return CommandResponse::succeed(['message' => 'Genre renamed!']);
     }
 }
diff --git a/app/Jobs/UpdateTagsForRenamedGenre.php b/app/Jobs/UpdateTagsForRenamedGenre.php
new file mode 100644
index 00000000..27e5b934
--- /dev/null
+++ b/app/Jobs/UpdateTagsForRenamedGenre.php
@@ -0,0 +1,97 @@
+<?php
+
+/**
+ * Pony.fm - A community for pony fan music.
+ * Copyright (C) 2016 Peter Deltchev
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+namespace Poniverse\Ponyfm\Jobs;
+
+use Auth;
+use Cache;
+use Log;
+use Poniverse\Ponyfm\Models\Genre;
+use Illuminate\Queue\InteractsWithQueue;
+use Illuminate\Contracts\Bus\SelfHandling;
+use Illuminate\Contracts\Queue\ShouldQueue;
+use Poniverse\Ponyfm\Models\Track;
+use SerializesModels;
+
+/**
+ * Class RenameGenre
+ *
+ * NOTE: It is assumed that the genre passed into this job has already been renamed!
+ * All this job does is update the tags in that genre's tracks.
+ *
+ * @package Poniverse\Ponyfm\Jobs
+ */
+class UpdateTagsForRenamedGenre extends Job implements SelfHandling, ShouldQueue
+{
+    use InteractsWithQueue, SerializesModels;
+
+    protected $executingUser;
+    protected $genreThatWasRenamed;
+    protected $lockKey;
+
+    /**
+     * Create a new job instance.
+     *
+     * @param Genre $genreThatWasRenamed
+     */
+    public function __construct(Genre $genreThatWasRenamed)
+    {
+        $this->executingUser = Auth::user();
+        $this->genreThatWasRenamed = $genreThatWasRenamed;
+
+        $this->lockKey = "genre-{$this->genreThatWasRenamed->id}-tag-update-lock";
+    }
+
+    /**
+     * Execute the job.
+     *
+     * @return void
+     */
+    public function handle()
+    {
+        // The user who kicked off this job is used when generating revision log entries.
+        Auth::login($this->executingUser);
+
+        // "Lock" this genre to prevent race conditions
+        if (Cache::has($this->lockKey)) {
+            Log::info("Tag updates for the \"{$this->genreThatWasRenamed->name}\" genre are currently in progress! Will try again in 30 seconds.");
+            $this->release(30);
+            return;
+
+        } else {
+            Cache::forever($this->lockKey, true);
+        }
+
+
+        $this->genreThatWasRenamed->tracks()->chunk(200, function ($tracks) {
+            foreach ($tracks as $track) {
+                /** @var Track $track */
+                $track->updateTags();
+            }
+        });
+
+        Cache::forget($this->lockKey);
+    }
+
+    public function failed()
+    {
+        Cache::forget($this->lockKey);
+    }
+}