Get rid of Repository interfaces

src/Core/Discussions/DiscussionRepository.php

@@ -0,0 +1,62 @@
+<?php namespace Flarum\Core\Discussions;
+
+use Illuminate\Database\Eloquent\Builder;
+use Flarum\Core\Users\User;
+
+class DiscussionRepository
+{
+    /**
+     * Get a new query builder for the discussions table.
+     *
+     * @return Builder
+     */
+    public function query()
+    {
+        return Discussion::query();
+    }
+
+    /**
+     * Find a discussion by ID, optionally making sure it is visible to a
+     * certain user, or throw an exception.
+     *
+     * @param integer $id
+     * @param \Flarum\Core\Users\User $user
+     * @return \Flarum\Core\Discussions\Discussion
+     */
+    public function findOrFail($id, User $user = null)
+    {
+        $query = Discussion::where('id', $id);
+
+        return $this->scopeVisibleTo($query, $user)->firstOrFail();
+    }
+
+    /**
+     * Get the IDs of discussions which a user has read completely.
+     *
+     * @param \Flarum\Core\Users\User $user
+     * @return array
+     */
+    public function getReadIds(User $user)
+    {
+        return Discussion::leftJoin('users_discussions', 'users_discussions.discussion_id', '=', 'discussions.id')
+            ->where('user_id', $user->id)
+            ->where('read_number', '<', 'last_post_number')
+            ->lists('id');
+    }
+
+    /**
+     * Scope a query to only include records that are visible to a user.
+     *
+     * @param Builder $query
+     * @param \Flarum\Core\Users\User $user
+     * @return Builder
+     */
+    protected function scopeVisibleTo(Builder $query, User $user = null)
+    {
+        if ($user !== null) {
+            $query->whereVisibleTo($user);
+        }
+
+        return $query;
+    }
+}