package author

import (
	"context"
	"errors"
	"tercul/internal/domain"
)

// AuthorQueries contains the query handlers for the author aggregate.
type AuthorQueries struct {
	repo domain.AuthorRepository
}

// NewAuthorQueries creates a new AuthorQueries handler.
func NewAuthorQueries(repo domain.AuthorRepository) *AuthorQueries {
	return &AuthorQueries{
		repo: repo,
	}
}

// GetAuthorByID retrieves an author by ID.
func (q *AuthorQueries) GetAuthorByID(ctx context.Context, id uint) (*domain.Author, error) {
	if id == 0 {
		return nil, errors.New("invalid author ID")
	}
	return q.repo.GetByID(ctx, id)
}

// ListAuthors returns a paginated list of authors.
func (q *AuthorQueries) ListAuthors(ctx context.Context, page, pageSize int) (*domain.PaginatedResult[domain.Author], error) {
	return q.repo.List(ctx, page, pageSize)
}

// ListAuthorsByCountryID returns a list of authors by country ID.
func (q *AuthorQueries) ListAuthorsByCountryID(ctx context.Context, countryID uint) ([]domain.Author, error) {
	if countryID == 0 {
		return nil, errors.New("invalid country ID")
	}
	return q.repo.ListByCountryID(ctx, countryID)
}

// GetAuthorsByIDs retrieves authors by a list of IDs.
func (q *AuthorQueries) GetAuthorsByIDs(ctx context.Context, ids []uint) ([]domain.Author, error) {
	return q.repo.GetByIDs(ctx, ids)
}