'boolean', ]; public function createdBy(): BelongsTo { return $this->belongsTo(User::class, 'created_by'); } public function items(): HasMany { return $this->hasMany(Item::class); } public function document_items(): HasMany { return $this->hasMany(DocumentItem::class); } public function bill_items(): HasMany { return $this->document_items()->where('type', 'bill'); } public function invoice_items(): HasMany { return $this->document_items()->where('type', 'invoice'); } protected static function newFactory(): Factory { return DiscountFactory::new(); } }