using Microsoft.EntityFrameworkCore;

public class UserDirectoryService : IUserDirectoryService
{
    private readonly AppDbContext _db;

    public UserDirectoryService(AppDbContext db) => _db = db;

    public async Task<IReadOnlyList<UserSummaryResponse>> ListByRoleAsync(UserRole? role)
    {
        var query = _db.Users.AsNoTracking().Where(u => u.IsActive);

        if (role.HasValue)
            query = query.Where(u => u.Role == role.Value);

        return await query
            .OrderBy(u => u.FullName)
            .Select(u => new UserSummaryResponse(
                u.Id,
                u.Username,
                u.FullName,
                u.Role.ToDbString()))
            .ToListAsync();
    }
}