add models and relations

app/Models/TableComment.php

@@ -0,0 +1,41 @@
+<?php
+
+namespace App\Models;
+
+use Illuminate\Database\Eloquent\Model;
+
+/**
+ * Comment on a data table
+ */
+class TableComment extends Model
+{
+    /** Context data table */
+    public function dataTable()
+    {
+        return $this->belongsTo(DataTable::class);
+    }
+
+    /** Parent comment (that we reply to; can be null) */
+    public function ancestor()
+    {
+        return $this->belongsTo(TableComment::class, 'ancestor_id');
+    }
+
+    /** Replies to this comment */
+    public function replies()
+    {
+        return $this->hasMany(TableComment::class, 'ancestor_id');
+    }
+
+    /** Authoring user */
+    public function author()
+    {
+        return $this->belongsTo(User::class, 'author_id');
+    }
+
+    /** Reports of this comment */
+    public function reportsOf()
+    {
+        return $this->morphMany(ContentReport::class, 'object');
+    }
+}