Implement notifications

src/Core/Commands/ReadNotificationCommand.php

@@ -0,0 +1,14 @@
+<?php namespace Flarum\Core\Commands;
+
+class ReadNotificationCommand
+{
+    public $notificationId;
+
+    public $user;
+
+    public function __construct($notificationId, $user)
+    {
+        $this->notificationId = $notificationId;
+        $this->user = $user;
+    }
+}

src/Core/CoreServiceProvider.php

@@ -10,6 +10,7 @@ use Flarum\Core\Models\Model;
 use Flarum\Core\Models\Forum;
 use Flarum\Core\Models\User;
 use Flarum\Core\Models\Discussion;
+use Flarum\Core\Models\Notification;
 use Flarum\Core\Search\GambitManager;
 
 class CoreServiceProvider extends ServiceProvider
@@ -25,6 +26,7 @@ class CoreServiceProvider extends ServiceProvider
 
         $this->registerEventHandlers($events);
         $this->registerPostTypes();
+        $this->registerNotificationTypes();
         $this->registerPermissions();
         $this->registerGambits();
         $this->setupModels();
@@ -112,11 +114,16 @@ class CoreServiceProvider extends ServiceProvider
         CommentPost::setFormatter($this->app['flarum.formatter']);
     }
 
+    public function registerNotificationTypes()
+    {
+        Notification::addType('renamed', 'Flarum\Core\Models\Discussion');
+    }
+
     public function registerEventHandlers($events)
     {
         $events->subscribe('Flarum\Core\Handlers\Events\DiscussionMetadataUpdater');
         $events->subscribe('Flarum\Core\Handlers\Events\UserMetadataUpdater');
-        $events->subscribe('Flarum\Core\Handlers\Events\RenamedPostCreator');
+        $events->subscribe('Flarum\Core\Handlers\Events\DiscussionRenamedNotifier');
         $events->subscribe('Flarum\Core\Handlers\Events\EmailConfirmationMailer');
     }
 

src/Core/Handlers/Commands/ReadNotificationCommandHandler.php

@@ -0,0 +1,28 @@
+<?php namespace Flarum\Core\Handlers\Commands;
+
+use Flarum\Core\Models\Notification;
+use Flarum\Core\Exceptions\PermissionDeniedException;
+use Flarum\Core\Support\DispatchesEvents;
+
+class ReadNotificationCommandHandler
+{
+    use DispatchesEvents;
+
+    public function handle($command)
+    {
+        $user = $command->user;
+
+        if (! $user->exists) {
+            throw new PermissionDeniedException;
+        }
+
+        $notification = Notification::where('user_id', $user->id)->findOrFail($command->notificationId);
+
+        $notification->read();
+
+        $notification->save();
+        $this->dispatchEventsFor($notification);
+
+        return $notification;
+    }
+}

src/Core/Handlers/Events/DiscussionRenamedNotifier.php

@@ -0,0 +1,61 @@
+<?php namespace Flarum\Core\Handlers\Events;
+
+use Flarum\Core\Events\DiscussionWasRenamed;
+use Flarum\Core\Models\RenamedPost;
+use Flarum\Core\Models\Notification;
+
+class DiscussionRenamedNotifier
+{
+    /**
+     * Register the listeners for the subscriber.
+     *
+     * @param  Illuminate\Events\Dispatcher  $events
+     * @return array
+     */
+    public function subscribe($events)
+    {
+        $events->listen('Flarum\Core\Events\DiscussionWasRenamed', __CLASS__.'@whenDiscussionWasRenamed');
+    }
+
+    public function whenDiscussionWasRenamed(DiscussionWasRenamed $event)
+    {
+        $post = $this->createRenamedPost($event);
+
+        $event->discussion->postWasAdded($post);
+
+        $this->createRenamedNotification($event, $post);
+    }
+
+    protected function createRenamedPost(DiscussionWasRenamed $event)
+    {
+        $post = RenamedPost::reply(
+            $event->discussion->id,
+            $event->user->id,
+            $event->oldTitle,
+            $event->discussion->title
+        );
+
+        $post->save();
+
+        return $post;
+    }
+
+    protected function createRenamedNotification(DiscussionWasRenamed $event, RenamedPost $post)
+    {
+        if ($event->discussion->start_user_id === $event->user->id) {
+            return false;
+        }
+
+        $notification = Notification::notify(
+            $event->discussion->start_user_id,
+            'renamed',
+            $event->user->id,
+            $event->discussion->id,
+            ['number' => $post->number, 'oldTitle' => $event->oldTitle]
+        );
+
+        $notification->save();
+
+        return $notification;
+    }
+}

src/Core/Handlers/Events/RenamedPostCreator.php

@@ -1,32 +0,0 @@
-<?php namespace Flarum\Core\Handlers\Events;
-
-use Flarum\Core\Events\DiscussionWasRenamed;
-use Flarum\Core\Models\RenamedPost;
-
-class RenamedPostCreator
-{
-    /**
-     * Register the listeners for the subscriber.
-     *
-     * @param  Illuminate\Events\Dispatcher  $events
-     * @return array
-     */
-    public function subscribe($events)
-    {
-        $events->listen('Flarum\Core\Events\DiscussionWasRenamed', __CLASS__.'@whenDiscussionWasRenamed');
-    }
-
-    public function whenDiscussionWasRenamed(DiscussionWasRenamed $event)
-    {
-        $post = RenamedPost::reply(
-            $event->discussion->id,
-            $event->user->id,
-            $event->oldTitle,
-            $event->discussion->title
-        );
-
-        $post->save();
-
-        $event->discussion->postWasAdded($post);
-    }
-}

src/Core/Models/Notification.php

@@ -0,0 +1,135 @@
+<?php namespace Flarum\Core\Models;
+
+use Flarum\Core\Support\MappedMorphTo;
+
+class Notification extends Model
+{
+    /**
+     * The table associated with the model.
+     *
+     * @var string
+     */
+    protected $table = 'notifications';
+
+    /**
+     * The attributes that should be mutated to dates.
+     *
+     * @var array
+     */
+    protected $dates = ['time'];
+
+    /**
+     * A map of notification types, as specified in the `type` column, to
+     * their subject classes.
+     *
+     * @var array
+     */
+    protected static $types = [];
+
+    public static function notify($userId, $type, $senderId, $subjectId, $data)
+    {
+        $notification = new static;
+
+        $notification->user_id    = $userId;
+        $notification->sender_id  = $senderId;
+        $notification->type       = $type;
+        $notification->subject_id = $subjectId;
+        $notification->data       = $data;
+        $notification->time       = time();
+
+        return $notification;
+    }
+
+    public function read()
+    {
+        $this->is_read = true;
+    }
+
+    /**
+     * Unserialize the data attribute.
+     *
+     * @param  string  $value
+     * @return string
+     */
+    public function getDataAttribute($value)
+    {
+        return json_decode($value);
+    }
+
+    /**
+     * Serialize the data attribute.
+     *
+     * @param  string  $value
+     */
+    public function setDataAttribute($value)
+    {
+        $this->attributes['data'] = json_encode($value);
+    }
+
+    /**
+     * Define the relationship with the notification's recipient.
+     *
+     * @return \Illuminate\Database\Eloquent\Relations\BelongsTo
+     */
+    public function user()
+    {
+        return $this->belongsTo('Flarum\Core\Models\User', 'user_id');
+    }
+
+    /**
+     * Define the relationship with the notification's sender.
+     *
+     * @return \Illuminate\Database\Eloquent\Relations\BelongsTo
+     */
+    public function sender()
+    {
+        return $this->belongsTo('Flarum\Core\Models\User', 'sender_id');
+    }
+
+    public function subject()
+    {
+        $name = 'subject';
+        $typeColumn = 'type';
+        $idColumn = 'subject_id';
+
+        // If the type value is null it is probably safe to assume we're eager loading
+        // the relationship. When that is the case we will pass in a dummy query as
+        // there are multiple types in the morph and we can't use single queries.
+        if (is_null($type = $this->$typeColumn))
+        {
+            return new MappedMorphTo(
+                $this->newQuery(), $this, $idColumn, null, $typeColumn, $name, static::$types
+            );
+        }
+
+        // If we are not eager loading the relationship we will essentially treat this
+        // as a belongs-to style relationship since morph-to extends that class and
+        // we will pass in the appropriate values so that it behaves as expected.
+        else
+        {
+            $class = static::$types[$type];
+            $instance = new $class;
+
+            return new MappedMorphTo(
+                $instance->newQuery(), $this, $idColumn, $instance->getKeyName(), $typeColumn, $name, static::$types
+            );
+        }
+    }
+
+    public static function getTypes()
+    {
+        return static::$types;
+    }
+
+    /**
+     * Register a notification type and its subject class.
+     *
+     * @param  string $type
+     * @param  string $class
+     * @return void
+     */
+    public static function addType($type, $class)
+    {
+        static::$types[$type] = $class;
+    }
+}

src/Core/Models/User.php

@@ -51,7 +51,7 @@ class User extends Model
      *
      * @var array
      */
-    protected $dates = ['join_time', 'last_seen_time', 'read_time'];
+    protected $dates = ['join_time', 'last_seen_time', 'read_time', 'notification_read_time'];
 
     /**
      * The hasher with which to hash passwords.
@@ -198,6 +198,18 @@ class User extends Model
         return $this;
     }
 
+    /**
+     * Mark all notifications as read by setting the user's notification_read_time.
+     *
+     * @return $this
+     */
+    public function markNotificationsAsRead()
+    {
+        $this->notification_read_time = time();
+
+        return $this;
+    }
+
     /**
      * Check if a given password matches the user's password.
      *
@@ -303,6 +315,11 @@ class User extends Model
         return (bool) $count;
     }
 
+    public function getUnreadNotificationsCount()
+    {
+        return $this->notifications()->where('time', '>', $this->notification_read_time ?: 0)->where('is_read', 0)->count(\DB::raw('DISTINCT type, subject_id'));
+    }
+
     /**
      * Check whether or not the user is an administrator.
      *
@@ -343,6 +360,16 @@ class User extends Model
         return $this->belongsToMany('Flarum\Core\Models\Group', 'users_groups');
     }
 
+    /**
+     * Define the relationship with the user's notifications.
+     *
+     * @return \Illuminate\Database\Eloquent\Relations\HasMany
+     */
+    public function notifications()
+    {
+        return $this->hasMany('Flarum\Core\Models\Notification');
+    }
+
     /**
      * Define the relationship with the user's permissions.
      *

src/Core/Repositories/EloquentNotificationRepository.php

@@ -0,0 +1,25 @@
+<?php namespace Flarum\Core\Repositories;
+
+use Flarum\Core\Models\Notification;
+use DB;
+
+class EloquentNotificationRepository implements NotificationRepositoryInterface
+{
+    public function findByUser($userId, $count = null, $start = 0)
+    {
+        $primaries = Notification::select(DB::raw('MAX(id) AS id'), DB::raw('SUM(is_read = 0) AS unread_count'))
+            ->where('user_id', $userId)
+            ->whereIn('type', array_keys(Notification::getTypes()))
+            ->groupBy('type', 'subject_id')
+            ->orderBy('time', 'desc')
+            ->skip($start)
+            ->take($count);
+
+        return Notification::with('subject')
+            ->select('notifications.*', 'p.unread_count')
+            ->mergeBindings($primaries->getQuery())
+            ->join(DB::raw('('.$primaries->toSql().') p'), 'notifications.id', '=', 'p.id')
+            ->orderBy('time', 'desc')
+            ->get();
+    }
+}

src/Core/Repositories/NotificationRepositoryInterface.php

@@ -0,0 +1,6 @@
+<?php namespace Flarum\Core\Repositories;
+
+interface NotificationRepositoryInterface
+{
+    public function findByUser($userId, $count = null, $start = 0);
+}

src/Core/Support/Actor.php

@@ -15,4 +15,9 @@ class Actor
     {
         $this->user = $user;
     }
+
+    public function isAuthenticated()
+    {
+        return (bool) $this->user;
+    }
 }

src/Core/Support/MappedMorphTo.php

@@ -0,0 +1,43 @@
+<?php namespace Flarum\Core\Support;
+
+use Illuminate\Database\Eloquent\Relations\MorphTo;
+use Illuminate\Database\Eloquent\Builder;
+use Illuminate\Database\Eloquent\Model;
+
+class MappedMorphTo extends MorphTo {
+
+	/**
+	 *
+	 * @var string
+	 */
+	protected $types;
+
+	/**
+	 * Create a new morph to relationship instance.
+	 *
+	 * @param  \Illuminate\Database\Eloquent\Builder  $query
+	 * @param  \Illuminate\Database\Eloquent\Model  $parent
+	 * @param  string  $foreignKey
+	 * @param  string  $otherKey
+	 * @param  string  $type
+	 * @param  string  $relation
+	 * @return void
+	 */
+	public function __construct(Builder $query, Model $parent, $foreignKey, $otherKey, $type, $relation, $types)
+	{
+		$this->types = $types;
+
+		parent::__construct($query, $parent, $foreignKey, $otherKey, $type, $relation);
+	}
+
+	/**
+	 * Create a new model instance by type.
+	 *
+	 * @param  string  $type
+	 * @return \Illuminate\Database\Eloquent\Model
+	 */
+	public function createModelByType($type)
+	{
+		return new $this->types[$type];
+	}
+}