package services

import (
	"git.mchus.pro/mchus/priceforge/internal/models"
	"gorm.io/gorm"
)

// purgeSeenLotNames removes polluted seen-registry rows where another system wrote a LOT name
// into qt_vendor_partnumber_seen.partnumber. Keep rows that already have an explicit PN mapping.
func purgeSeenLotNames(db *gorm.DB) error {
	if db == nil {
		return nil
	}
	return db.
		Where("EXISTS (SELECT 1 FROM lot l WHERE LOWER(TRIM(l.lot_name)) = LOWER(TRIM(qt_vendor_partnumber_seen.partnumber)))").
		Where("NOT EXISTS (SELECT 1 FROM qt_partnumber_book_items pb WHERE LOWER(TRIM(pb.partnumber)) = LOWER(TRIM(qt_vendor_partnumber_seen.partnumber)))").
		Delete(&models.VendorPartnumberSeen{}).
		Error
}