// Package db provides database access for the IMC application.
// It uses GORM (Go ORM) for database operations.

package db

// =============================================================================
// VirtualDomain - Mail domain operations
// These functions interact with the ISPmail virtual_domains table.
// =============================================================================

// GetAllDomains retrieves all domains with user and alias counts.
// Returns a slice of DomainStats (includes counts) or an error.
func (d *DB) GetAllDomains() ([]DomainStats, error) {
	var domains []VirtualDomain
	if err := d.Order("name ASC").Find(&domains).Error; err != nil {
		return nil, err
	}

	stats := make([]DomainStats, len(domains))
	for i, dom := range domains {
		var userCount, aliasCount int64
		d.Model(&VirtualUser{}).Where("domain_id = ?", dom.ID).Count(&userCount)
		d.Model(&VirtualAlias{}).Where("domain_id = ?", dom.ID).Count(&aliasCount)

		stats[i] = DomainStats{
			ID:         dom.ID,
			Name:       dom.Name,
			UserCount:  userCount,
			AliasCount: aliasCount,
		}
	}

	if stats == nil {
		stats = []DomainStats{}
	}
	return stats, nil
}

// GetDomainByID retrieves a single domain by its ID.
// id: the domain's ID.
// Returns the VirtualDomain or an error (including "record not found").
func (d *DB) GetDomainByID(id uint) (*VirtualDomain, error) {
	var domain VirtualDomain
	if err := d.Where("id = ?", id).First(&domain).Error; err != nil {
		return nil, err
	}
	return &domain, nil
}

// GetDomainByName retrieves a single domain by its name.
// name: the domain name (e.g., "example.org").
// Returns the VirtualDomain or an error (including "record not found").
func (d *DB) GetDomainByName(name string) (*VirtualDomain, error) {
	var domain VirtualDomain
	if err := d.Where("name = ?", name).First(&domain).Error; err != nil {
		return nil, err
	}
	return &domain, nil
}

// CreateDomain creates a new mail domain.
// name: the domain name (e.g., "example.org").
// Returns the created VirtualDomain or an error.
func (d *DB) CreateDomain(name string) (*VirtualDomain, error) {
	domain := VirtualDomain{Name: name}
	if err := d.Create(&domain).Error; err != nil {
		return nil, err
	}
	return &domain, nil
}

// DeleteDomain permanently removes a domain and all associated users and aliases.
// id: the domain's ID to delete.
// This also deletes all virtual_users and virtual_aliases belonging to this domain.
// Returns an error if the deletion fails.
func (d *DB) DeleteDomain(id uint) error {
	tx := d.Begin()
	defer func() { tx.Rollback() }()

	if err := tx.Where("domain_id = ?", id).Delete(&VirtualUser{}).Error; err != nil {
		return err
	}
	if err := tx.Where("domain_id = ?", id).Delete(&VirtualAlias{}).Error; err != nil {
		return err
	}
	if err := tx.Delete(&VirtualDomain{}, id).Error; err != nil {
		return err
	}

	return tx.Commit().Error
}