public class EventPartnerStatueTokenExchangeArcContext : IEventPartnerTokenExchangeContext
{
    private EventPartnerStatueArc _arc;

    public string RedPointKey => _arc != null ? _arc.GetRedPointKey() : string.Empty;
    public int TicketCount => _arc?.Model != null ? _arc.Model.TicketCount : 0;
    public int TicketItemId => _arc?.TableContext != null ? _arc.TableContext.GetTicketId() : 0;
    public float LureInflationRate => _arc?.Model != null ? _arc.Model.LureInflationRate : 1f;
    public int TokenExchangeItemId => _arc?.TableContext != null ? _arc.TableContext.GetTokenExchangeItemId() : 0;
    public int TokenExchangeId => _arc?.TableContext != null ? _arc.TableContext.GetTokenExchangeId() : 0;

    public void BindArc(EventPartnerStatueArc arc)
    {
        _arc = arc;
    }

    public void AddTicket(int amount)
    {
        if (_arc?.Model == null)
            return;
        _arc.Model.AddTicket(amount);
    }
}

public interface IEventPartnerTokenExchangeContext
{
    int TokenExchangeId { get; }
    string RedPointKey { get; }
    int TicketCount { get; }
    float LureInflationRate { get; }
    void AddTicket(int amount);
    int TokenExchangeItemId { get; }
}