package shared

import (
	"fmt"
	"time"

	"galaxy/user/internal/domain/account"
	"galaxy/user/internal/domain/common"
	"galaxy/user/internal/ports"
)

// BuildRaceNameReservation constructs one validated race-name reservation
// record for userID and raceName at reservedAt.
func BuildRaceNameReservation(
	policy ports.RaceNamePolicy,
	userID common.UserID,
	raceName common.RaceName,
	reservedAt time.Time,
) (account.RaceNameReservation, error) {
	if policy == nil {
		return account.RaceNameReservation{}, fmt.Errorf("build race-name reservation: race-name policy must not be nil")
	}
	if err := userID.Validate(); err != nil {
		return account.RaceNameReservation{}, fmt.Errorf("build race-name reservation: %w", err)
	}
	if err := raceName.Validate(); err != nil {
		return account.RaceNameReservation{}, fmt.Errorf("build race-name reservation: %w", err)
	}
	if err := common.ValidateTimestamp("build race-name reservation reserved at", reservedAt); err != nil {
		return account.RaceNameReservation{}, err
	}

	canonicalKey, err := policy.CanonicalKey(raceName)
	if err != nil {
		return account.RaceNameReservation{}, fmt.Errorf("build race-name reservation: %w", err)
	}

	record := account.RaceNameReservation{
		CanonicalKey: canonicalKey,
		UserID:       userID,
		RaceName:     raceName,
		ReservedAt:   reservedAt.UTC(),
	}
	if err := record.Validate(); err != nil {
		return account.RaceNameReservation{}, fmt.Errorf("build race-name reservation: %w", err)
	}

	return record, nil
}