buid new app

app/Models/Category.php

@@ -0,0 +1,25 @@
+<?php
+
+namespace App\Models;
+
+use Illuminate\Database\Eloquent\Model;
+
+class Category extends Model
+{
+    protected $fillable = ['user_id', 'parent_id', 'name', 'color', 'icon'];
+
+    public function parent()
+    {
+        return $this->belongsTo(Category::class, 'parent_id');
+    }
+
+    public function children()
+    {
+        return $this->hasMany(Category::class, 'parent_id');
+    }
+
+    public function expenses()
+    {
+        return $this->hasMany(Expense::class);
+    }
+}