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

package db

// =============================================================================
// VirtualAlias - Mail alias operations
// These functions interact with the ISPmail virtual_aliases table.
// =============================================================================

// GetAllAliases retrieves all email aliases with their domain names.
// Returns a slice of AliasWithDomain (includes domain name) or an error.
func (d *DB) GetAllAliases() ([]AliasWithDomain, error) {
	var aliases []VirtualAlias
	if err := d.Preload("Domain").Find(&aliases).Error; err != nil {
		return nil, err
	}

	result := make([]AliasWithDomain, len(aliases))
	for i, a := range aliases {
		result[i] = AliasWithDomain{
			VirtualAlias: a,
			DomainName:   "",
		}
		if a.Domain != nil {
			result[i].DomainName = a.Domain.Name
		}
	}

	if result == nil {
		result = []AliasWithDomain{}
	}
	return result, nil
}

// GetAliasesByDomain retrieves all aliases belonging to a specific domain.
// domainID: the ID of the domain.
// Returns a slice of VirtualAlias or an error.
func (d *DB) GetAliasesByDomain(domainID uint) ([]VirtualAlias, error) {
	var aliases []VirtualAlias
	if err := d.Where("domain_id = ?", domainID).Find(&aliases).Error; err != nil {
		return nil, err
	}
	if aliases == nil {
		aliases = []VirtualAlias{}
	}
	return aliases, nil
}

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

// GetAliasBySource looks up an alias by its source address.
// source: the source email address (the alias).
// Returns the VirtualAlias or an error (including "record not found").
func (d *DB) GetAliasBySource(source string) (*VirtualAlias, error) {
	var alias VirtualAlias
	if err := d.Where("source = ?", source).First(&alias).Error; err != nil {
		return nil, err
	}
	return &alias, nil
}

// CreateAlias creates a new email alias without a domain association.
// source: the source email address (the alias).
// destination: the destination email address (where mail is forwarded to).
// Returns the created VirtualAlias or an error.
func (d *DB) CreateAlias(source, destination string) (*VirtualAlias, error) {
	alias := VirtualAlias{
		Source:      source,
		Destination: destination,
	}
	if err := d.Create(&alias).Error; err != nil {
		return nil, err
	}
	return &alias, nil
}

// CreateAliasInDomain creates a new email alias in a specific domain.
// source: the source email address (the alias).
// destination: the destination email address (where mail is forwarded to).
// domainID: the ID of the domain this alias belongs to.
// Returns the created VirtualAlias or an error.
func (d *DB) CreateAliasInDomain(source, destination string, domainID uint) (*VirtualAlias, error) {
	alias := VirtualAlias{
		DomainID:    domainID,
		Source:      source,
		Destination: destination,
	}
	if err := d.Create(&alias).Error; err != nil {
		return nil, err
	}
	return &alias, nil
}

// DeleteAlias permanently removes an alias from the database.
// id: the alias's ID to delete.
// Returns an error if the deletion fails.
func (d *DB) DeleteAlias(id uint) error {
	return d.Delete(&VirtualAlias{}, id).Error
}